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Groups > sci.physics.relativity > #591990 > unrolled thread
| Started by | Richard Hachel <r.hachel@tiscali.fr> |
|---|---|
| First post | 2022-09-18 22:39 +0000 |
| Last post | 2022-12-07 23:06 +0000 |
| Articles | 20 on this page of 290 — 33 participants |
Back to article view | Back to sci.physics.relativity
The error of relativistic physicists explained Richard Hachel <r.hachel@tiscali.fr> - 2022-09-18 22:39 +0000
Re: The error of relativistic physicists explained "Dono." <eggy20011951@gmail.com> - 2022-09-18 17:14 -0700
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-09-18 17:37 -0700
Re: The error of relativistic physicists explained "Dono." <eggy20011951@gmail.com> - 2022-09-18 17:55 -0700
Re: The error of relativistic physicists explained Maciej Wozniak <maluwozniak@gmail.com> - 2022-09-18 23:17 -0700
Re: The error of relativistic physicists explained Stan Fultoni <fultonistan@gmail.com> - 2022-09-18 19:32 -0700
Re: The error of relativistic physicists explained Stan Fultoni <fultonistan@gmail.com> - 2022-09-18 20:12 -0700
Re: The error of relativistic physicists explained Richard Hachel <r.hachel@tiscali.fr> - 2022-09-19 09:35 +0000
Re: The error of relativistic physicists explained Richard Hachel <r.hachel@tiscali.fr> - 2022-09-19 09:44 +0000
Re: The error of relativistic physicists explained Richard Hachel <r.hachel@tiscali.fr> - 2022-09-19 09:53 +0000
Re: The error of relativistic physicists explained Richard Hachel <r.hachel@tiscali.fr> - 2022-09-20 13:59 +0000
Re: The error of relativistic physicists explained Stan Fultoni <fultonistan@gmail.com> - 2022-09-20 08:23 -0700
Re: The error of relativistic physicists explained Mikko <mikko.levanto@iki.fi> - 2022-09-19 12:10 +0300
Re: The error of relativistic physicists explained Richard Hachel <r.hachel@tiscali.fr> - 2022-09-19 11:29 +0000
Re: The error of relativistic physicists explained Stan Fultoni <fultonistan@gmail.com> - 2022-09-19 19:42 -0700
Re: The error of relativistic physicists explained Mikko <mikko.levanto@iki.fi> - 2022-09-20 13:18 +0300
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-09-20 15:15 -0400
Re: The error of relativistic physicists explained Justus Basurto <trso@subsrbob.au> - 2022-09-20 19:34 +0000
Re: The error of relativistic physicists explained Justus Basurto <trso@subsrbob.au> - 2022-09-20 19:47 +0000
Re: The error of relativistic physicists explained Justus Basurto <trso@subsrbob.au> - 2022-09-20 19:54 +0000
Re: The error of relativistic physicists explained Richard Hachel <r.hachel@tiscali.fr> - 2022-09-20 21:45 +0000
Re: The error of relativistic physicists explained Justus Basurto <trso@subsrbob.au> - 2022-09-20 21:56 +0000
Re: The error of relativistic physicists explained Stan Fultoni <fultonistan@gmail.com> - 2022-09-20 15:47 -0700
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-09-20 19:51 -0400
Re: The error of relativistic physicists explained Richard Hachel <r.hachel@tiscali.fr> - 2022-09-21 10:59 +0000
Re: The error of relativistic physicists explained Stan Fultoni <fultonistan@gmail.com> - 2022-09-21 06:32 -0700
Re: The error of relativistic physicists explained Richard Hachel <r.hachel@tiscali.fr> - 2022-09-21 23:20 +0000
Re: The error of relativistic physicists explained Stan Fultoni <fultonistan@gmail.com> - 2022-09-21 16:53 -0700
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-09-21 19:29 -0400
Re: The error of relativistic physicists explained Maciej Wozniak <maluwozniak@gmail.com> - 2022-09-21 23:14 -0700
Re: The error of relativistic physicists explained Jeiker Carboni <iree@eoaijoje.br> - 2022-09-22 14:26 +0000
Re: The error of relativistic physicists explained Jeiker Carboni <iree@eoaijoje.br> - 2022-09-22 15:27 +0000
Re: The error of relativistic physicists explained Stan Fultoni <fultonistan@gmail.com> - 2022-09-20 22:42 -0700
Re: The error of relativistic physicists explained Maciej Wozniak <maluwozniak@gmail.com> - 2022-09-20 22:51 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-09-23 07:03 +0200
Re: The error of relativistic physicists explained Richard Hachel <r.hachel@tiscali.fr> - 2022-09-23 11:50 +0000
Re: The error of relativistic physicists explained "Dono." <eggy20011951@gmail.com> - 2022-09-23 07:22 -0700
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-09-23 12:55 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-09-24 08:21 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-09-23 23:59 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-09-24 09:24 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-09-24 11:24 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-09-25 08:44 +0200
Re: The error of relativistic physicists explained "Paul B. Andersen" <pba@paulba.no> - 2022-09-25 14:56 +0200
Re: The error of relativistic physicists explained Richard Hachel <r.hachel@tiscali.fr> - 2022-09-26 20:32 +0000
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-01 07:40 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-11-01 00:23 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-05 08:22 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-11-05 11:08 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-06 08:41 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-11-06 10:35 -0800
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-07 14:06 -0500
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-08 07:19 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-11-08 00:09 -0800
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-08 10:27 -0500
Re: The error of relativistic physicists explained Maciej Wozniak <maluwozniak@gmail.com> - 2022-11-08 08:54 -0800
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-09 09:10 -0500
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-16 08:15 +0100
Re: The error of relativistic physicists explained Athel Cornish-Bowden <acornish@imm.cnrs.fr> - 2022-11-16 09:14 +0100
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-16 12:59 -0500
Re: The error of relativistic physicists explained Maciej Wozniak <maluwozniak@gmail.com> - 2022-11-16 10:37 -0800
Re: The error of relativistic physicists explained Jules Scotti <ujsl@ocjssuis.os> - 2022-11-16 18:40 +0000
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-18 08:33 +0100
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-20 20:56 -0500
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-23 08:55 +0100
Re: The error of relativistic physicists explained Everly Segreti <ille@leysgsei.re> - 2022-11-08 18:52 +0000
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-09 09:24 -0500
Re: The error of relativistic physicists explained Everly Segreti <ille@leysgsei.re> - 2022-11-09 16:17 +0000
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-09 12:34 -0500
Re: The error of relativistic physicists explained Everly Segreti <ille@leysgsei.re> - 2022-11-09 19:30 +0000
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-11-09 12:37 -0800
Re: The error of relativistic physicists explained Everly Segreti <ille@leysgsei.re> - 2022-11-10 06:21 +0000
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-11-09 23:19 -0800
Re: The error of relativistic physicists explained Everly Segreti <ille@leysgsei.re> - 2022-11-10 07:59 +0000
Re: The error of relativistic physicists explained Urbano Napoleoni <uiiu@ilaonpno.ai> - 2022-12-07 23:10 +0000
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-12-07 15:28 -0800
Re: The error of relativistic physicists explained Everly Segreti <ille@leysgsei.re> - 2022-11-10 06:47 +0000
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-10 08:34 +0100
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-12 01:32 -0500
Re: The error of relativistic physicists explained Stefano Martelli <ftor@asanlnit.ir> - 2022-11-12 09:06 +0000
Re: The error of relativistic physicists explained Athel Cornish-Bowden <acornish@imm.cnrs.fr> - 2022-11-12 11:27 +0100
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-13 09:58 +0100
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-13 11:17 -0500
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-14 08:11 +0100
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-14 11:31 -0500
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-15 09:20 +0100
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-16 08:06 +0100
Re: The error of relativistic physicists explained Athel Cornish-Bowden <acornish@imm.cnrs.fr> - 2022-11-16 09:12 +0100
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-16 12:56 -0500
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-17 09:03 +0100
Re: The error of relativistic physicists explained Athel Cornish-Bowden <acornish@imm.cnrs.fr> - 2022-11-17 10:22 +0100
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-18 08:03 +0100
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-20 21:01 -0500
Re: The error of relativistic physicists explained Blake Armanni <blea@arrkare.in> - 2022-11-21 10:41 +0000
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-21 13:37 -0500
Re: The error of relativistic physicists explained Blake Armanni <blea@arrkare.in> - 2022-11-21 20:33 +0000
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-23 13:21 -0500
Re: The error of relativistic physicists explained Forest Vaccaro <asoa@ctrsreca.vr> - 2022-11-23 19:10 +0000
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-23 09:14 +0100
Re: The error of relativistic physicists explained nospam@de-ster.demon.nl (J. J. Lodder) - 2022-11-17 13:10 +0100
Re: The error of relativistic physicists explained Athel Cornish-Bowden <acornish@imm.cnrs.fr> - 2022-11-17 15:07 +0100
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-18 08:10 +0100
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-09 07:57 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-11-08 23:15 -0800
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-09 12:03 -0500
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-10 08:21 +0100
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-12 01:55 -0500
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-20 09:19 +0100
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-20 21:18 -0500
Re: The error of relativistic physicists explained Maciej Wozniak <maluwozniak@gmail.com> - 2022-11-20 22:12 -0800
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-21 08:52 +0100
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-22 08:37 +0100
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-11-23 18:31 -0500
Re: The error of relativistic physicists explained Maciej Wozniak <maluwozniak@gmail.com> - 2022-11-23 22:32 -0800
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-24 08:49 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-09-25 13:08 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-09-26 08:46 +0200
Re: The error of relativistic physicists explained "Dono." <eggy20011951@gmail.com> - 2022-09-26 09:25 -0700
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-09-26 15:42 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-09-27 08:33 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-09-27 13:01 -0700
Re: The error of relativistic physicists explained Nikki Baldini <inai@dilainii.ib> - 2022-09-27 23:17 +0000
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-09-28 08:15 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-09-28 00:04 -0700
Re: The error of relativistic physicists explained Nikki Baldini <inai@dilainii.ib> - 2022-09-28 16:10 +0000
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-09-28 11:55 -0700
Re: The error of relativistic physicists explained Nikki Baldini <inai@dilainii.ib> - 2022-09-28 19:23 +0000
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-09-28 12:46 -0700
Re: The error of relativistic physicists explained Nikki Baldini <inai@dilainii.ib> - 2022-09-28 21:28 +0000
Re: The error of relativistic physicists explained Nikki Baldini <inai@dilainii.ib> - 2022-09-28 21:34 +0000
Re: The error of relativistic physicists explained whodat <whodaat@void.nowgre.com> - 2022-09-28 16:17 -0500
Re: The error of relativistic physicists explained Urbano Napoleoni <uiiu@ilaonpno.ai> - 2022-12-07 23:25 +0000
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-12-07 15:29 -0800
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-09-28 11:53 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-09-29 08:48 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-09-29 10:54 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-09-30 09:12 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-01 16:05 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-02 09:58 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-02 03:34 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-03 08:55 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-03 01:02 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-06 08:21 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-06 00:57 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-06 20:04 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-06 12:00 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-07 07:21 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-07 14:14 -0700
Re: The error of relativistic physicists explained Urbano Stilo <nuor@riotlaur.iu> - 2022-10-08 03:37 +0000
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-08 08:19 +0200
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-10-08 03:37 -0400
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-08 14:29 -0700
Re: The error of relativistic physicists explained Michel Marconi <iinc@lcrallem.or> - 2022-10-08 22:21 +0000
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-10 08:37 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-10 01:56 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-11 08:03 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-11 01:06 -0700
Re: The error of relativistic physicists explained Maciej Wozniak <maluwozniak@gmail.com> - 2022-10-11 01:25 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-12 08:17 +0200
Re: The error of relativistic physicists explained Maciej Wozniak <maluwozniak@gmail.com> - 2022-10-11 23:32 -0700
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-12 11:27 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-13 09:33 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-13 13:58 -0700
Re: The error of relativistic physicists explained Woodrow Adessi <reds@odirsodo.er> - 2022-10-13 21:03 +0000
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-14 08:49 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-14 01:11 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-15 09:24 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-15 03:05 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-16 09:30 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-16 13:02 -0700
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-16 13:19 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-17 08:18 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-17 02:48 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-18 08:56 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-19 14:51 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-20 21:14 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-20 13:27 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-21 09:03 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-21 02:05 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-22 10:36 +0200
Re: The error of relativistic physicists explained Oscar Alcheri <ohci@iessicsr.rn> - 2022-10-22 08:42 +0000
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-22 12:04 -0700
Re: The error of relativistic physicists explained Oscar Alcheri <ohci@iessicsr.rn> - 2022-10-22 19:47 +0000
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-22 19:54 -0700
Re: The error of relativistic physicists explained Maciej Wozniak <maluwozniak@gmail.com> - 2022-10-22 23:00 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-23 09:13 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-23 02:45 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-25 07:49 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-24 23:53 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-25 09:26 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-25 12:32 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-28 09:16 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-28 20:51 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-30 08:25 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-30 13:51 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-31 09:40 +0100
Re: The error of relativistic physicists explained Mikko <mikko.levanto@iki.fi> - 2022-10-31 11:26 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-31 17:42 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-01 07:59 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-11-01 00:35 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-02 09:04 +0100
Re: The error of relativistic physicists explained Mikko <mikko.levanto@iki.fi> - 2022-11-02 11:39 +0200
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-04 08:18 +0100
Re: The error of relativistic physicists explained Mikko <mikko.levanto@iki.fi> - 2022-11-04 12:12 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-11-04 10:49 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-05 08:35 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-11-05 11:10 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-06 08:51 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-11-06 10:47 -0800
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-08 07:35 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-11-08 00:07 -0800
Re: The error of relativistic physicists explained Everly Segreti <ille@leysgsei.re> - 2022-11-08 19:28 +0000
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-26 08:48 +0200
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-10-22 22:31 -0400
Re: The error of relativistic physicists explained Maciej Wozniak <maluwozniak@gmail.com> - 2022-10-22 22:57 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-23 09:24 +0200
Re: The error of relativistic physicists explained Oscar Alcheri <ohci@iessicsr.rn> - 2022-10-23 07:46 +0000
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-23 02:48 -0700
Re: The error of relativistic physicists explained Maciej Wozniak <maluwozniak@gmail.com> - 2022-10-23 02:51 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-25 08:05 +0200
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-10-25 19:48 -0400
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-27 08:51 +0200
Re: The error of relativistic physicists explained Chase Rossini <asoi@riisscss.ho> - 2022-10-28 10:49 +0000
Re: The error of relativistic physicists explained Urbano Stilo <nuor@riotlaur.iu> - 2022-10-08 04:01 +0000
Re: The error of relativistic physicists explained nospam@de-ster.demon.nl (J. J. Lodder) - 2022-10-08 14:02 +0200
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-09 08:30 +0200
Re: The error of relativistic physicists explained Michel Marconi <iinc@lcrallem.or> - 2022-10-09 12:02 +0000
Re: The error of relativistic physicists explained nospam@de-ster.demon.nl (J. J. Lodder) - 2022-10-09 22:29 +0200
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-10-07 02:05 -0400
Re: The error of relativistic physicists explained Urbano Stilo <nuor@riotlaur.iu> - 2022-10-08 03:57 +0000
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-08 08:47 +0200
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-10-08 03:43 -0400
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-09 08:36 +0200
Re: The error of relativistic physicists explained Michel Marconi <iinc@lcrallem.or> - 2022-10-09 12:14 +0000
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-10 08:23 +0200
Re: The error of relativistic physicists explained Mandy Stabile <alts@ilnnnbsl.ed> - 2022-10-10 15:40 +0000
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-11 08:08 +0200
Re: The error of relativistic physicists explained "Paul B. Andersen" <pba@paulba.no> - 2022-10-02 14:37 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-02 14:27 -0700
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-02 14:38 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-03 09:21 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-03 01:08 -0700
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-10-03 11:59 -0400
Re: The error of relativistic physicists explained Douglass Nervetti <dlul@esivlen.an> - 2022-10-03 18:31 +0000
Re: The error of relativistic physicists explained Urbano Napoleoni <uiiu@ilaonpno.ai> - 2022-12-07 23:03 +0000
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-12-07 15:24 -0800
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-06 08:29 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-06 00:58 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-10-06 20:11 +0200
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-06 11:31 -0700
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-10-06 11:33 -0700
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-11-30 09:19 +0100
Re: The error of relativistic physicists explained Lee Barsetti <erre@battaete.tr> - 2022-11-30 16:12 +0000
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-11-30 20:15 -0800
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-12-01 10:46 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-12-01 12:40 -0800
Re: The error of relativistic physicists explained Maciej Wozniak <maluwozniak@gmail.com> - 2022-12-01 13:15 -0800
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-12-02 08:22 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-12-02 03:17 -0800
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-12-05 08:51 +0100
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-12-05 03:03 -0800
Re: The error of relativistic physicists explained Dallas Basurto <aarr@maramr.sa> - 2022-12-05 18:34 +0000
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-12-06 09:08 +0100
Re: The error of relativistic physicists explained whodat <whodaat@void.nowgre.com> - 2022-12-06 13:01 -0600
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-12-07 09:12 +0100
Re: The error of relativistic physicists explained whodat <whodaat@void.nowgre.com> - 2022-12-07 12:31 -0600
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-12-08 08:06 +0100
Re: The error of relativistic physicists explained whodat <whodaat@void.nowgre.com> - 2022-12-08 10:17 -0600
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-12-09 07:54 +0100
Re: The error of relativistic physicists explained whodat <whodaat@void.nowgre.com> - 2022-12-09 10:56 -0600
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-12-10 07:53 +0100
Re: The error of relativistic physicists explained Jim Pennino <jimp@gonzo.specsol.net> - 2022-12-10 06:53 -0800
Re: The error of relativistic physicists explained whodat <whodaat@void.nowgre.com> - 2022-12-10 10:06 -0600
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-12-11 07:48 +0100
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-12-14 08:29 +0100
Re: The error of relativistic physicists explained whodat <whodaat@void.nowgre.com> - 2022-12-14 06:06 -0600
Re: The error of relativistic physicists explained Fabio Brambilla <oaab@llbaboaa.am> - 2022-12-14 17:36 +0000
Re: The error of relativistic physicists explained whodat <whodaat@void.nowgre.com> - 2022-12-14 13:48 -0600
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-12-15 10:15 +0100
Re: The error of relativistic physicists explained "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-12-15 01:17 -0800
Re: The error of relativistic physicists explained whodat <whodaat@void.nowgre.com> - 2022-12-15 05:57 -0600
Re: The error of relativistic physicists explained "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2022-12-16 12:45 -0800
Re: The error of relativistic physicists explained whodat <whodaat@void.nowgre.com> - 2022-12-15 05:52 -0600
Re: The error of relativistic physicists explained Thomas Heger <ttt_heg@web.de> - 2022-12-16 08:43 +0100
Re: The error of relativistic physicists explained Jim Pennino <jimp@gonzo.specsol.net> - 2022-12-07 11:23 -0800
Re: The error of relativistic physicists explained Volney <volney@invalid.invalid> - 2022-12-02 01:25 -0500
Re: The error of relativistic physicists explained Nikki Baldini <inai@dilainii.ib> - 2022-09-28 21:46 +0000
Re: The error of relativistic physicists explained Nikki Baldini <inai@dilainii.ib> - 2022-09-27 16:39 +0000
Re: The error of relativistic physicists explained JanPB <filmart@gmail.com> - 2022-09-27 12:34 -0700
Re: The error of relativistic physicists explained Urbano Napoleoni <uiiu@ilaonpno.ai> - 2022-12-07 23:06 +0000
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| From | Thomas Heger <ttt_heg@web.de> |
|---|---|
| Date | 2022-10-03 08:55 +0200 |
| Message-ID | <jpvfagFeb9eU1@mid.individual.net> |
| In reply to | #592732 |
Am 02.10.2022 um 12:34 schrieb JanPB: >>>> The reason is, that the wave is coming from some remote location, which >>>> does not move, once you do. >>> >>> Again, you are introducing irrelevancies here (like the observer actually >>> sitting at the origin, etc.). The only thing that's relevant here is the wave >>> direction (l, m, n) and its other properties: speed (c), frequency (w), >>> vector value components (X0, Y0, Z0) and (L0, M0, N0). >> The coordinates can move in relativity with the observer. >> >> For reasons of simplicity I always use coordinates, where the observer >> rests at the ceter of his own coordinate system. >> >> This is a possible setting, but others are also possible. But I prefer >> this one usually, because it makes things simpler. >> >> In case of the relevant coordinates of the point, we could also move the >> coordinate system to that point, what would make x=y=z=0. >> >> This is also a possible setting. >> >> As we can also rotate coordinate system, we could rotate that system in >> the direction, where the z-axis points to the origin of the waves. >> >> This would make l=m=0 and n=1 (what make things even easier). >> >> It would also show, that Einstein's equation is totally absurd. > > No, you don't understand what's happening here. The idea is to find > the frequency of the plane wave measured by the moving observer, > given that frequency measured by the stationary one is known and > the direction of the wave is known. That's why the axes are not > aligned with that direction: we want to find how the frequency as > measured by the moving observer varies according to that direction. Of course I understand, what Einstein WANTED! But his wishes are not under considertation, but what he had actually written. Quote (§ 7, page 15) "In the system K, very far from the origin of co-ordinates, let there be a source of electrodynamic waves, which in a part of space containing the origin of co-ordinates may be represented to a sufficient degree of approximation by the equations X = X_0 sinΦ, L = L_0 sinΦ, ... " X is the x-component of the electric field strength vector and X_0 the maximum of this vector (the amplitude) in the x-direction. The point , to which this vector belongs is the point (x,y,z) (measured in K-coordinates). Now these coordinates are entirely irrelevant for the field strength at that point, because the coordinate system K is only used as reference to define the point, but has no physical impact on its state. If he had the intentions you mentioned, then he should have derived equations, which served his purpose. But instead he wrote equations, that contain the irrelavant quantities x,y and z, which are the coordinates of the point in respect to coordinate system K. But K can be placed aribitrary to the liking of the experimenter, because it is only the reference to measure the location, but not the location itself. And there is absolutely no reason to assume, that the placement of the coordinates have an influence on the state of a point, which gets hit by a wave from some remote location. ... TH >
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| From | JanPB <filmart@gmail.com> |
|---|---|
| Date | 2022-10-03 01:02 -0700 |
| Message-ID | <396e0f3f-ee15-49fe-843d-bc3cb98f8b0an@googlegroups.com> |
| In reply to | #592784 |
On Sunday, October 2, 2022 at 11:55:17 PM UTC-7, Thomas Heger wrote: > Am 02.10.2022 um 12:34 schrieb JanPB: > > >>>> The reason is, that the wave is coming from some remote location, which > >>>> does not move, once you do. > >>> > >>> Again, you are introducing irrelevancies here (like the observer actually > >>> sitting at the origin, etc.). The only thing that's relevant here is the wave > >>> direction (l, m, n) and its other properties: speed (c), frequency (w), > >>> vector value components (X0, Y0, Z0) and (L0, M0, N0). > >> The coordinates can move in relativity with the observer. > >> > >> For reasons of simplicity I always use coordinates, where the observer > >> rests at the ceter of his own coordinate system. > >> > >> This is a possible setting, but others are also possible. But I prefer > >> this one usually, because it makes things simpler. > >> > >> In case of the relevant coordinates of the point, we could also move the > >> coordinate system to that point, what would make x=y=z=0. > >> > >> This is also a possible setting. > >> > >> As we can also rotate coordinate system, we could rotate that system in > >> the direction, where the z-axis points to the origin of the waves. > >> > >> This would make l=m=0 and n=1 (what make things even easier). > >> > >> It would also show, that Einstein's equation is totally absurd. > > > > No, you don't understand what's happening here. The idea is to find > > the frequency of the plane wave measured by the moving observer, > > given that frequency measured by the stationary one is known and > > the direction of the wave is known. That's why the axes are not > > aligned with that direction: we want to find how the frequency as > > measured by the moving observer varies according to that direction. > Of course I understand, what Einstein WANTED! It's not Einstein. It's high school physics, like Halliday-Resnick, etc. > But his wishes are not under considertation, but what he had actually > written. > > > Quote (§ 7, page 15) > > "In the system K, very far from the origin of co-ordinates, let there be > a source of electrodynamic waves, This is just a fancy way of saying "let there be a plane wave in space given". > which in a part of space containing > the origin of co-ordinates may be represented to a sufficient degree of > approximation by the equations > X = X_0 sinΦ, L = L_0 sinΦ, > ... > " Yes, thats' the plane wave. > X is the x-component of the electric field strength vector and X_0 the > maximum of this vector (the amplitude) in the x-direction. > > The point , to which this vector belongs is the point (x,y,z) (measured > in K-coordinates). It's not "the" point, it's the formula describing this wave in all space (for all values of (x, y, z) ). > Now these coordinates are entirely irrelevant for the field strength at > that point, because the coordinate system K is only used as reference to > define the point, but has no physical impact on its state. You are completely mixed up in the basics. It is assumed that a plane wave is travelling through (all) space. At each point (x, y, z) (as labelled by K) the value of the electric field is (X, Y, Z), where X, Y, Z are defined by the formulas you quoted above. > If he had the intentions you mentioned, then he should have derived > equations, which served his purpose. Those equations are basic and predate Maxwell, their derivation does not belong in a 1905 physics paper, it's appropriate in textbooks. Likewise, mathematical papers do not define real numbers, sets, and the like, even if they use them. In other words: get real. > But instead he wrote equations, > that contain the irrelavant quantities x,y and z, They are very relevant, the values X, Y, Z depend on x, y, z (the wave changes its value from point to point, it's not a constant function). > which are the > coordinates of the point in respect to coordinate system K. Yes. They are necessary there. Just like when you describe a sine wave in one dimension: value = sin(x). The x is necessary and affects the values from point to point. This is just a certain 3D version of it. > But K can be placed aribitrary to the liking of the experimenter, > because it is only the reference to measure the location, but not the > location itself. K is fixed. Reread the beginning of the paper. And obviously for the Doppler calculation it must be fixed since Einstein wants to see how the result depends on the angle phi of the wave direction. > And there is absolutely no reason to assume, that the placement of the > coordinates have an influence on the state of a point, which gets hit by > a wave from some remote location. Irrelevant. I mean simply not even wrong. -- Jan
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| From | Thomas Heger <ttt_heg@web.de> |
|---|---|
| Date | 2022-10-06 08:21 +0200 |
| Message-ID | <jq7aerFkujtU1@mid.individual.net> |
| In reply to | #592787 |
Am 03.10.2022 um 10:02 schrieb JanPB: ... >> Quote (§ 7, page 15) >> >> "In the system K, very far from the origin of co-ordinates, let there be >> a source of electrodynamic waves, > > This is just a fancy way of saying "let there be a plane wave in space given". > >> which in a part of space containing >> the origin of co-ordinates may be represented to a sufficient degree of >> approximation by the equations >> X = X_0 sinΦ, L = L_0 sinΦ, >> ... >> " > > Yes, thats' the plane wave. > >> X is the x-component of the electric field strength vector and X_0 the >> maximum of this vector (the amplitude) in the x-direction. >> >> The point , to which this vector belongs is the point (x,y,z) (measured >> in K-coordinates). > > It's not "the" point, it's the formula describing this wave in all space (for > all values of (x, y, z) ). If you want to adress all points, you need to say so. If you write just (x,y,z) without any comment, this would mean: take an arbitrary but fixed point with the coordinates x, y and z. This point (x, y, z) is therefor one single point, which can be arbitrarily chosen, but only once. If you like to adress all points, which have coodinates like (x, y, z) in K, you could do that just by saying so. But without such a statement, (x,y,z) is just one single point. >> Now these coordinates are entirely irrelevant for the field strength at >> that point, because the coordinate system K is only used as reference to >> define the point, but has no physical impact on its state. > > You are completely mixed up in the basics. It is assumed that a plane > wave is travelling through (all) space. At each point (x, y, z) (as labelled > by K) the value of the electric field is (X, Y, Z), where X, Y, Z are > defined by the formulas you quoted above. The formulas are wrong, because they contain the coordinates in repspect to coordinate system K instead of coordinates in respect to the emitter. The cordinates in respect to K are entirely irrelevant, because K can be arbitrarily chosen. And any such decision would have an effect on the coordinates, but not on the state of these points. Also irrelevant are the angles of the wave in respect to the coordinate system K, because coordinate systems can also be rotated. This would influence the direction cosines, but not the state of these points. Therefore the equations of Einstein are nonsense, not because they are mathematically wrong, but because the wrong quantities went into them. >> If he had the intentions you mentioned, then he should have derived >> equations, which served his purpose. > > Those equations are basic and predate Maxwell, their derivation does > not belong in a 1905 physics paper, it's appropriate in textbooks. Likewise, > mathematical papers do not define real numbers, sets, and the like, even > if they use them. In other words: get real. Just try to explain, how the numbers x,y,z, l, m and n are used in these equations, even if they havn't any influence on the situation, the equations are supposed to describe. >> But instead he wrote equations, >> that contain the irrelavant quantities x,y and z, > > They are very relevant, the values X, Y, Z depend on x, y, z (the wave > changes its value from point to point, it's not a constant function). NO!!!!! The value X, Y an Z are components of the electric field strength vector at point (x, y, z). You could leave the coordinates away entirely or move or rotate system K, but still you would have an electric field strength vector at that point. This field would also not be effected by any change of the coordinate system. Coordinates are actually human artifacts and the points they describe are not supposed to know anything about them. >> which are the >> coordinates of the point in respect to coordinate system K. > > Yes. They are necessary there. Just like when you describe a > sine wave in one dimension: value = sin(x). The x is necessary and > affects the values from point to point. This is just a certain 3D version of it. If you like to describe the wave and its effect on the space it passes through, you certainly will concentrate on the wave. Waves usually start from a certain emitter and pass through space. The points the wave hits on its way are influenced and set into a certain state. Let the wave move with c, then we have a function of the wave like psi= A * sin (t*c). (something like that) BUT: the coordinates of the wave start at the emitter, not at an arbitrary observer. But the values l, m, n, x, y, and z are measures, which relate to the observer, instead of to the emitter. >> But K can be placed aribitrary to the liking of the experimenter, >> because it is only the reference to measure the location, but not the >> location itself. > > K is fixed. Reread the beginning of the paper. And obviously for the > Doppler calculation it must be fixed since Einstein wants to see how > the result depends on the angle phi of the wave direction. What do you mean with 'fixed'??? In the context of SRT K is called 'stationary'. As inertial motion cannot be distinguished from being stationary in SRT, any coordinate system in inertial motion can also be called 'stationary'. I usually use a setting, where the observer calls his own system stationary and rests in the center. This setting is very intuitive, because it reflects our usual subjectivistic view on the world. But 'fixed' is not defined, because only relative velocities are defined and absolute space was rejected. ... TH
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| From | JanPB <filmart@gmail.com> |
|---|---|
| Date | 2022-10-06 00:57 -0700 |
| Message-ID | <8e83282e-5f44-4f91-90d9-abada6ddff12n@googlegroups.com> |
| In reply to | #592963 |
On Wednesday, October 5, 2022 at 11:21:21 PM UTC-7, Thomas Heger wrote: > Am 03.10.2022 um 10:02 schrieb JanPB: > > ... > >> Quote (§ 7, page 15) > >> > >> "In the system K, very far from the origin of co-ordinates, let there be > >> a source of electrodynamic waves, > > > > This is just a fancy way of saying "let there be a plane wave in space given". > > > >> which in a part of space containing > >> the origin of co-ordinates may be represented to a sufficient degree of > >> approximation by the equations > >> X = X_0 sinΦ, L = L_0 sinΦ, > >> ... > >> " > > > > Yes, thats' the plane wave. > > > >> X is the x-component of the electric field strength vector and X_0 the > >> maximum of this vector (the amplitude) in the x-direction. > >> > >> The point , to which this vector belongs is the point (x,y,z) (measured > >> in K-coordinates). > > > > It's not "the" point, it's the formula describing this wave in all space (for > > all values of (x, y, z) ). > If you want to adress all points, you need to say so. > If you write just (x,y,z) without any comment, this would mean: > take an arbitrary but fixed point with the coordinates x, y and z. No, standard usage is to state any constraints explicitly, not to state the lack of them explicitly (unless it's significant fort some reason). However, in this case even this is unimportant because here Einstein simply quotes a well-known textbook formula for a plane wave. It requires no further comment since science papers are not meant to be read by beginners. > This point (x, y, z) is therefor one single point, which can be > arbitrarily chosen, but only once. No, the formula describes the wave at every point at every time. This is FAPP high school physics. There is really nothing to discuss here. > If you like to adress all points, which have coodinates like (x, y, z) > in K, you could do that just by saying so. You could but it's simply tedious, pedantic, and redundant in a science paper. Just like in a math paper people just use certain concepts without defining them. If an author of such paper suddenly started defining what derivative was, the peer reviewer would most likely ask the author to cross it out, it would simply look borderline idiotic. > But without such a statement, (x,y,z) is just one single point. It isn't in the paper. Einstein here quotes a formula that had been well-known for I don't know exactly how long (decades). > >> Now these coordinates are entirely irrelevant for the field strength at > >> that point, because the coordinate system K is only used as reference to > >> define the point, but has no physical impact on its state. > > > > You are completely mixed up in the basics. It is assumed that a plane > > wave is travelling through (all) space. At each point (x, y, z) (as labelled > > by K) the value of the electric field is (X, Y, Z), where X, Y, Z are > > defined by the formulas you quoted above. > The formulas are wrong, because they contain the coordinates in repspect > to coordinate system K instead of coordinates in respect to the emitter. > > The cordinates in respect to K are entirely irrelevant, because K can be > arbitrarily chosen. It was chosen in Section 3 arbitrarily and then fixed. The wave is propagating through space and is described by that formula. > Also irrelevant are the angles of the wave in respect to the coordinate > system K, because coordinate systems can also be rotated. For the duration of the argument (the entire paper, actually), the system K is fixed. > Therefore the equations of Einstein are nonsense, not because they are > mathematically wrong, but because the wrong quantities went into them. No, they are 100% correct. Also, completely standard. > >> If he had the intentions you mentioned, then he should have derived > >> equations, which served his purpose. > > > > Those equations are basic and predate Maxwell, their derivation does > > not belong in a 1905 physics paper, it's appropriate in textbooks. Likewise, > > mathematical papers do not define real numbers, sets, and the like, even > > if they use them. In other words: get real. > Just try to explain, how the numbers x,y,z, l, m and n are used in these > equations, even if they havn't any influence on the situation, the > equations are supposed to describe. Given any spatial point and an instant of time, this defines four numbers (t, x, y, z), the K-coordinates of that point and that instant. You plug in those four numbers and get the components of the E and B fields (X, Y, Z) and (L, M, N) at that point and at that instant of time. > >> But instead he wrote equations, > >> that contain the irrelavant quantities x,y and z, > > > > They are very relevant, the values X, Y, Z depend on x, y, z (the wave > > changes its value from point to point, it's not a constant function). > NO!!!!! > > The value X, Y an Z are components of the electric field strength vector > at point (x, y, z). Yes. So why did you say "NO"? The components of E depend on the location and the time. You seem to have a problem with the Bleeding Obvious Department. > You could leave the coordinates away entirely or move or rotate system > K, K is fixed for the duration of Section 7 (the entire paper, actually). After the entire paper is done, you can change K to another system and then redo the paper in it (it'll be fixed, again). > but still you would have an electric field strength vector at that > point. This field would also not be effected by any change of the > coordinate system. The system K is fixed. > Coordinates are actually human artifacts and the points they describe > are not supposed to know anything about them. Sure, but once a coordinate system is specified, its labels can be used since they then will refer to the actual positions and time instants. > >> which are the > >> coordinates of the point in respect to coordinate system K. > > > > Yes. They are necessary there. Just like when you describe a > > sine wave in one dimension: value = sin(x). The x is necessary and > > affects the values from point to point. This is just a certain 3D version of it. > If you like to describe the wave and its effect on the space it passes > through, you certainly will concentrate on the wave. > > Waves usually start from a certain emitter and pass through space. The > points the wave hits on its way are influenced and set into a certain state. > > Let the wave move with c, then we have a function of the wave like > psi= A * sin (t*c). > > (something like that) > > BUT: the coordinates of the wave start at the emitter, not at an > arbitrary observer. Yes. And the emitter is at infinity. In fact the emitter is unimportant, we only are interested in the wave it generates here. It's presumed plane which is a limiting case putting the emitter at infinity. > But the values l, m, n, x, y, and z are measures, which relate to the > observer, instead of to the emitter. The emitter is irrelevant here. > >> But K can be placed aribitrary to the liking of the experimenter, > >> because it is only the reference to measure the location, but not the > >> location itself. > > > > K is fixed. Reread the beginning of the paper. And obviously for the > > Doppler calculation it must be fixed since Einstein wants to see how > > the result depends on the angle phi of the wave direction. > What do you mean with 'fixed'??? Just fixed. Not changing once it was selected in Section 3. > In the context of SRT K is called 'stationary'. Yes. > As inertial motion cannot be distinguished from being stationary in SRT, > any coordinate system in inertial motion can also be called 'stationary'. Fixed means it's not changing. The assignment method for labels (quadruples of numbers) does not change. BTW, I don't know if you realise this, but this conversation is getting positively surreal. -- Jan
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| From | Thomas Heger <ttt_heg@web.de> |
|---|---|
| Date | 2022-10-06 20:04 +0200 |
| Message-ID | <jq8jkvFr486U1@mid.individual.net> |
| In reply to | #592965 |
Am 06.10.2022 um 09:57 schrieb JanPB: > If he had the intentions you mentioned, then he should have derived >>>> equations, which served his purpose. >>> >>> Those equations are basic and predate Maxwell, their derivation does >>> not belong in a 1905 physics paper, it's appropriate in textbooks. Likewise, >>> mathematical papers do not define real numbers, sets, and the like, even >>> if they use them. In other words: get real. >> Just try to explain, how the numbers x,y,z, l, m and n are used in these >> equations, even if they havn't any influence on the situation, the >> equations are supposed to describe. > > Given any spatial point and an instant of time, this defines four numbers > (t, x, y, z), the K-coordinates of that point and that instant. You plug in those > four numbers and get the components of the E and B fields (X, Y, Z) and > (L, M, N) at that point and at that instant of time. The coordinates are entirely irrelavant for the points, because coordinate systems are human artifact, while points in space are not. >>>> But instead he wrote equations, >>>> that contain the irrelavant quantities x,y and z, >>> >>> They are very relevant, the values X, Y, Z depend on x, y, z (the wave >>> changes its value from point to point, it's not a constant function). >> NO!!!!! >> >> The value X, Y an Z are components of the electric field strength vector >> at point (x, y, z). > > Yes. So why did you say "NO"? The components of E depend on > the location and the time. You seem to have a problem with > the Bleeding Obvious Department. But the coordinates are NOT the location, but a measure of the locations distances to certain axes of a coordinate system. Example: my location is now 'Berlin'. (btw: this is a town in Germany.) This town has also coordinates, thou not Chartesian ones, but coordinates which are measured as latitude and longitude relative to our home planet 'Earth'. Therefore, locations and coordinates are not the same thing. The wave from some distance source is now influencing the location, but not the coordinates. Also the coordinates do not influence the location, because coordinate systems can be chosen. And the outcome of such a decision cannot have a physical effect. >> You could leave the coordinates away entirely or move or rotate system >> K, > > K is fixed for the duration of Section 7 (the entire paper, actually). > After the entire paper is done, you can change K to another system > and then redo the paper in it (it'll be fixed, again). ??? I do not understand, what you want to say. You can actually regard any coordinates system in inertial motion as stationary. I prefer a setting, where the observer rests in the center of the stationary system. But other settings are also possible, while usually a littel more difficult to handle. >> but still you would have an electric field strength vector at that >> point. This field would also not be effected by any change of the >> coordinate system. > > The system K is fixed. > >> Coordinates are actually human artifacts and the points they describe >> are not supposed to know anything about them. > > Sure, but once a coordinate system is specified, its labels can > be used since they then will refer to the actual positions and > time instants. Yes. But what actually do you express with these coordinates? If I place the coordinate system in the lower left corner of my room and measure the position of the Moon with it, then how could the Moon possibly know, that I have relocated my coordinates to the upper right corner (or the wave at point (x,y,z)? >>>> which are the >>>> coordinates of the point in respect to coordinate system K. >>> >>> Yes. They are necessary there. Just like when you describe a >>> sine wave in one dimension: value = sin(x). The x is necessary and >>> affects the values from point to point. This is just a certain 3D version of it. >> If you like to describe the wave and its effect on the space it passes >> through, you certainly will concentrate on the wave. >> >> Waves usually start from a certain emitter and pass through space. The >> points the wave hits on its way are influenced and set into a certain state. >> >> Let the wave move with c, then we have a function of the wave like >> psi= A * sin (t*c). Sorry: here I made an error, because the equation meant was psi = A * sin(t*omega) >> (something like that) >> >> BUT: the coordinates of the wave start at the emitter, not at an >> arbitrary observer. > > Yes. And the emitter is at infinity. In fact the emitter is unimportant, > we only are interested in the wave it generates here. It's presumed > plane which is a limiting case putting the emitter at infinity. No, the emitter should NOT be at infinity! (To use infinities here would be a very bad idea.) For instance: an emitter at infinity cannot send a signal here, because that would take infinite time to travel. As infitely far distance of the emitter would reduce the signal strength to zero, we could measure no signals from there, neither. For infinite plane waves we would actually need infinitely large antennas. So, in total, plane waves are only usable as local approximation to real world waves, which are more or less spherical. But this restriction would hinder movements further away from the zone, to which the approximation is valid enough. >> But the values l, m, n, x, y, and z are measures, which relate to the >> observer, instead of to the emitter. > > The emitter is irrelevant here. The observer is irrelevant, while the emitter is not (because the emitter is actually sending out the wave). >>>> But K can be placed aribitrary to the liking of the experimenter, >>>> because it is only the reference to measure the location, but not the >>>> location itself. >>> >>> K is fixed. Reread the beginning of the paper. And obviously for the >>> Doppler calculation it must be fixed since Einstein wants to see how >>> the result depends on the angle phi of the wave direction. >> What do you mean with 'fixed'??? > > Just fixed. Not changing once it was selected in Section 3. Well, ok. But what difference does it make, if I chose the coordinate system prior to the experiment or afterwards? >> In the context of SRT K is called 'stationary'. > > Yes. > >> As inertial motion cannot be distinguished from being stationary in SRT, >> any coordinate system in inertial motion can also be called 'stationary'. > > Fixed means it's not changing. The assignment method for labels (quadruples > of numbers) does not change. > > BTW, I don't know if you realise this, but this conversation is getting > positively surreal. Not more surreal than most other discussions here. TH
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| From | JanPB <filmart@gmail.com> |
|---|---|
| Date | 2022-10-06 12:00 -0700 |
| Message-ID | <7a81e0cc-6154-4b10-b34e-6547c3f4bb3bn@googlegroups.com> |
| In reply to | #592981 |
On Thursday, October 6, 2022 at 11:04:20 AM UTC-7, Thomas Heger wrote: > Am 06.10.2022 um 09:57 schrieb JanPB: > > If he had the intentions you mentioned, then he should have derived > >>>> equations, which served his purpose. > >>> > >>> Those equations are basic and predate Maxwell, their derivation does > >>> not belong in a 1905 physics paper, it's appropriate in textbooks. Likewise, > >>> mathematical papers do not define real numbers, sets, and the like, even > >>> if they use them. In other words: get real. > >> Just try to explain, how the numbers x,y,z, l, m and n are used in these > >> equations, even if they havn't any influence on the situation, the > >> equations are supposed to describe. > > > > Given any spatial point and an instant of time, this defines four numbers > > (t, x, y, z), the K-coordinates of that point and that instant. You plug in those > > four numbers and get the components of the E and B fields (X, Y, Z) and > > (L, M, N) at that point and at that instant of time. > The coordinates are entirely irrelavant for the points, because > coordinate systems are human artifact, while points in space are not. > >>>> But instead he wrote equations, > >>>> that contain the irrelavant quantities x,y and z, > >>> > >>> They are very relevant, the values X, Y, Z depend on x, y, z (the wave > >>> changes its value from point to point, it's not a constant function). > >> NO!!!!! > >> > >> The value X, Y an Z are components of the electric field strength vector > >> at point (x, y, z). > > > > Yes. So why did you say "NO"? The components of E depend on > > the location and the time. You seem to have a problem with > > the Bleeding Obvious Department. > But the coordinates are NOT the location, but a measure of the locations > distances to certain axes of a coordinate system. Coordinates denote locations. They are literally 1-1 functions between locations (manifold points in the model) and the relevant Cartesian space (R^3 in this case: (x, y, z)). > Example: > > my location is now 'Berlin'. > > (btw: this is a town in Germany.) Been there many many times, nice place. A couple of months ago last time, I usually stay around Charlottenburg :-) > The wave from some distance source is now influencing the location, but > not the coordinates. The source is irrelevant. Only the wave is. > Also the coordinates do not influence the location, because coordinate > systems can be chosen. And the outcome of such a decision cannot have a > physical effect. This is a non-sequitur. Again, you seem to have COMPLETELY fantastical, utterly surreal, concepts regarding physics and mathematics. A classic case of "fractally wrong" arises as a consequence. > >> You could leave the coordinates away entirely or move or rotate system > >> K, > > > > K is fixed for the duration of Section 7 (the entire paper, actually). > > After the entire paper is done, you can change K to another system > > and then redo the paper in it (it'll be fixed, again). > ??? > > I do not understand, what you want to say. > > You can actually regard any coordinates system in inertial motion as > stationary. > > I prefer a setting, where the observer rests in the center of the > stationary system. > > But other settings are also possible, while usually a littel more > difficult to handle. It doesn't matter. Again, the system K is fixed. It can be chosen arbitrarily at first but then it remains fixed for the duration of the argument. > >> but still you would have an electric field strength vector at that > >> point. This field would also not be effected by any change of the > >> coordinate system. > > > > The system K is fixed. > > > >> Coordinates are actually human artifacts and the points they describe > >> are not supposed to know anything about them. > > > > Sure, but once a coordinate system is specified, its labels can > > be used since they then will refer to the actual positions and > > time instants. > Yes. But what actually do you express with these coordinates? Locations in space and instants of time. > If I place the coordinate system in the lower left corner of my room and > measure the position of the Moon with it, then how could the Moon > possibly know, that I have relocated my coordinates to the upper right > corner (or the wave at point (x,y,z)? The system is fixed, you don't "relocate" anything while you're performing the analysis. > >>>> which are the > >>>> coordinates of the point in respect to coordinate system K. > >>> > >>> Yes. They are necessary there. Just like when you describe a > >>> sine wave in one dimension: value = sin(x). The x is necessary and > >>> affects the values from point to point. This is just a certain 3D version of it. > >> If you like to describe the wave and its effect on the space it passes > >> through, you certainly will concentrate on the wave. > >> > >> Waves usually start from a certain emitter and pass through space. The > >> points the wave hits on its way are influenced and set into a certain state. > >> > >> Let the wave move with c, then we have a function of the wave like > >> psi= A * sin (t*c). > Sorry: here I made an error, because the equation meant was > psi = A * sin(t*omega) > >> (something like that) > >> > >> BUT: the coordinates of the wave start at the emitter, not at an > >> arbitrary observer. > > > > Yes. And the emitter is at infinity. In fact the emitter is unimportant, > > we only are interested in the wave it generates here. It's presumed > > plane which is a limiting case putting the emitter at infinity. > No, the emitter should NOT be at infinity! It must be because the waves are planar. But it makes no differnece where it is anyway. Only the waves are important to express the Doppler question fully. > (To use infinities here would be a very bad idea.) The location of the source is not used. Besides, it's merely a limiting case of a faraway source. Again, none of this is relevant. > For instance: an emitter at infinity cannot send a signal here, because > that would take infinite time to travel. Again, it's a limit and it's also irrelevant. Point masses don't exist either yet nobody is negating Newtonian mechanics because of that. Those are simple, well-understood limits. They are in this case irrelevant anyway. > As infitely far distance of the emitter would reduce the signal strength > to zero, we could measure no signals from there, neither. Irrelevant. We assume the wave is as described by the formula. Have you ever derived Snell's law of refraction from Maxwell's equations? It's exactly the same approach: start with a plane wave approaching the medium boundary. It's in any decent undergrad E&M textbook. > For infinite plane waves we would actually need infinitely large antennas. Irrelevant. The wave is given by the formula and is idealised to fill the entire space. Just like point masses are idealised to "anti-fill" only a single point. > So, in total, plane waves are only usable as local approximation to > real world waves, which are more or less spherical. Yes. Plane waves are idealisations of spherical waves with a source as far as we please to satisfy any assumed marginof error. > >>> K is fixed. Reread the beginning of the paper. And obviously for the > >>> Doppler calculation it must be fixed since Einstein wants to see how > >>> the result depends on the angle phi of the wave direction. > >> What do you mean with 'fixed'??? > > > > Just fixed. Not changing once it was selected in Section 3. > Well, ok. > > But what difference does it make, if I chose the coordinate system prior > to the experiment or afterwards? It was you who made a big deal out of changing the system (rotating it, etc.) and it would supposedly render useless labelling space points using it. So Ipointed out that throughout Section 7 the syetm K is presumed unchanging, so that spatial points and time instants possess unambiguous coordinate labels. > > BTW, I don't know if you realise this, but this conversation is getting > > positively surreal. > Not more surreal than most other discussions here. No, I'd say a bit more. Here you are approaching Archimedes Plutonium levels of what (in his case) is basically the entire structure of thought process falling apart. You are not quite there yet :-) -- Jan
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| From | Thomas Heger <ttt_heg@web.de> |
|---|---|
| Date | 2022-10-07 07:21 +0200 |
| Message-ID | <jq9rapF2c5iU1@mid.individual.net> |
| In reply to | #592985 |
Am 06.10.2022 um 21:00 schrieb JanPB: >>>> Waves usually start from a certain emitter and pass through space. The >>>> points the wave hits on its way are influenced and set into a certain state. >>>> >>>> Let the wave move with c, then we have a function of the wave like >>>> psi= A * sin (t*c). >> Sorry: here I made an error, because the equation meant was >> psi = A * sin(t*omega) >>>> (something like that) >>>> >>>> BUT: the coordinates of the wave start at the emitter, not at an >>>> arbitrary observer. >>> >>> Yes. And the emitter is at infinity. In fact the emitter is unimportant, >>> we only are interested in the wave it generates here. It's presumed >>> plane which is a limiting case putting the emitter at infinity. >> No, the emitter should NOT be at infinity! > > It must be because the waves are planar. But it makes no differnece where > it is anyway. Only the waves are important to express the Doppler > question fully. You think as a physicist and I as an engineer. Engineers say: "Sorry, but we cannot place antennas at infinity" Physicsts say: "Inifinity is required, because we want plane waves" >> (To use infinities here would be a very bad idea.) > > The location of the source is not used. Besides, it's merely a limiting > case of a faraway source. Again, none of this is relevant. How can you say 'The location of the source is not used. ' ??? 'The location of the source' is actually used, while the location of the observer or the center of the coordinate system K is not. >> For instance: an emitter at infinity cannot send a signal here, because >> that would take infinite time to travel. > > Again, it's a limit and it's also irrelevant. Point masses don't > exist either yet nobody is negating Newtonian mechanics because > of that. Those are simple, well-understood limits. They are in > this case irrelevant anyway. I have actually criticised the use of the term 'point mass' in Einstein's text, too. Mass is an attribute of 3-dimensional objects, while points have zero. >> As infitely far distance of the emitter would reduce the signal strength >> to zero, we could measure no signals from there, neither. > > Irrelevant. We assume the wave is as described by the formula. To use infinity is a really bad idea. Einstein used this idea, too. And I had mentioned, that velocity in respect to infinity is always zero. We could, however, design some kind of 'infinity algebra'. Goes like this: infinity is abriviated to 'inf' r denotes a rational number greater than zero so: r/0=inf inf + (-inf)=0 sin(0)= 1 sin(inf)=0 r/inf =0 inf²=inf sqrt(inf) = inf inf has a 3d direction hence can have an angle to other infinities a vector containing inf has the 'length' inf ... > Have you ever derived Snell's law of refraction from > Maxwell's equations? It's exactly the same approach: start with > a plane wave approaching the medium boundary. It's in any decent > undergrad E&M textbook. We have a different 'environment' in SRT, which relates more to cosmology than to optics >> For infinite plane waves we would actually need infinitely large antennas. > > Irrelevant. The wave is given by the formula and is idealised to > fill the entire space. Just like point masses are idealised to "anti-fill" > only a single point. How far do you want to stretch that 'idealisation'? Actually plane waves are only valid as local approximation. > >> So, in total, plane waves are only usable as local approximation to >> real world waves, which are more or less spherical. > > Yes. Plane waves are idealisations of spherical waves with a source > as far as we please to satisfy any assumed marginof error. But still plane waves are not real. The real waves stem from a certain source and distribute spherically from there. >>>>> K is fixed. Reread the beginning of the paper. And obviously for the >>>>> Doppler calculation it must be fixed since Einstein wants to see how >>>>> the result depends on the angle phi of the wave direction. >>>> What do you mean with 'fixed'??? >>> >>> Just fixed. Not changing once it was selected in Section 3. >> Well, ok. >> >> But what difference does it make, if I chose the coordinate system prior >> to the experiment or afterwards? > > It was you who made a big deal out of changing the system (rotating it, etc.) > and it would supposedly render useless labelling space points using it. > So Ipointed out that throughout Section 7 the syetm K is presumed unchanging, > so that spatial points and time instants possess unambiguous coordinate labels. I wanted to express, that I think, the coordinates in respect to the observer are irrelevant. As proof I have 'relocated' the system (as 'thought experiment'). Since the change of the coordinates would not change the field at that point, the coordinates are irrelevant for the point and the wave. >>> BTW, I don't know if you realise this, but this conversation is getting >>> positively surreal. >> Not more surreal than most other discussions here. > > No, I'd say a bit more. Here you are approaching Archimedes Plutonium > levels of what (in his case) is basically the entire structure of thought > process falling apart. You are not quite there yet :-) You mean 'Androcles' ??? TH
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| From | JanPB <filmart@gmail.com> |
|---|---|
| Date | 2022-10-07 14:14 -0700 |
| Message-ID | <f0882d80-7163-4445-9edd-0879d193ee6dn@googlegroups.com> |
| In reply to | #593001 |
On Thursday, October 6, 2022 at 10:21:33 PM UTC-7, Thomas Heger wrote: > Am 06.10.2022 um 21:00 schrieb JanPB: > > >>>> Waves usually start from a certain emitter and pass through space. The > >>>> points the wave hits on its way are influenced and set into a certain state. > >>>> > >>>> Let the wave move with c, then we have a function of the wave like > >>>> psi= A * sin (t*c). > >> Sorry: here I made an error, because the equation meant was > >> psi = A * sin(t*omega) > >>>> (something like that) > >>>> > >>>> BUT: the coordinates of the wave start at the emitter, not at an > >>>> arbitrary observer. > >>> > >>> Yes. And the emitter is at infinity. In fact the emitter is unimportant, > >>> we only are interested in the wave it generates here. It's presumed > >>> plane which is a limiting case putting the emitter at infinity. > >> No, the emitter should NOT be at infinity! > > > > It must be because the waves are planar. But it makes no differnece where > > it is anyway. Only the waves are important to express the Doppler > > question fully. > You think as a physicist and I as an engineer. > > Engineers say: "Sorry, but we cannot place antennas at infinity" But this is simply irrelevant, no matter who you are. The problem is to find a formula for the Doppler shift. The simplifying assumption is that the wave is a plane one. The reason is that the error due to making this assumption can be made arbitrarily small by moving the source as far as needed to cover the error. So regardless of who you are, you simply make things obvious and simple by assuming an ideal plane wave, secure in the knowledge that the actual shift will differ by a vanishingly small number. And e.g. distant stars are... well, DISTANT already anyway :-) > Physicsts say: "Inifinity is required, because we want plane waves" But this is just an idealisation, engineers do it all the time. > > The location of the source is not used. Besides, it's merely a limiting > > case of a faraway source. Again, none of this is relevant. > How can you say 'The location of the source is not used. ' ??? It just isn't. What's needed to calculate the Doppler effect is the wave's frequency and direction. > 'The location of the source' is actually used, while the location of the > observer or the center of the coordinate system K is not. The location of the source is not used besides the obvious assumption that in real life it would have to be far away enough to make the resulting wave a plane one over the region being experimented with. Thus for calculation one can simply assume the limiting ideal case with the waves perfectly planar. This is done all the time. Have you ever done any physics? Like deriving Fresnel laws or Snell's law? As for the location of the K-observer, it's not assumed he is at the origin. All the formulas in Section 7 are valid at any location, it does not have to be the origin. > >> For instance: an emitter at infinity cannot send a signal here, because > >> that would take infinite time to travel. > > > > Again, it's a limit and it's also irrelevant. Point masses don't > > exist either yet nobody is negating Newtonian mechanics because > > of that. Those are simple, well-understood limits. They are in > > this case irrelevant anyway. > I have actually criticised the use of the term 'point mass' in > Einstein's text, too. > > Mass is an attribute of 3-dimensional objects, while points have zero. Yes, but Newton and Maxwell and everyone else uses them for obvious reasons. Of course it is not _a priori_ clear that point masses or point charges are not contradictory within the actual theories they are a part of but the fact is they are not. As everyting else in science AND engineering, they are a very good idealisations which yield results for real (extended) masses and charges. > >> As infitely far distance of the emitter would reduce the signal strength > >> to zero, we could measure no signals from there, neither. > > > > Irrelevant. We assume the wave is as described by the formula. > To use infinity is a really bad idea. Why? It's like point masses and charges. It's simply an approximation of a faraway source, with the added capability of making the approximation error arbitrarily small. This is a HUGE practical and theoretical advantage. We are talking 18th century stuff here. > Einstein used this idea, too. And I had mentioned, that velocity in > respect to infinity is always zero. Irrelevant. > We could, however, design some kind of 'infinity algebra'. Goes like this: That's completely outside the scope. > > Have you ever derived Snell's law of refraction from > > Maxwell's equations? It's exactly the same approach: start with > > a plane wave approaching the medium boundary. It's in any decent > > undergrad E&M textbook. > We have a different 'environment' in SRT, which relates more to > cosmology than to optics That's not my point. You deny the plane wave approach its validity for derivationof certain results. Be it Doppler or Snell or Fresnel - they all use plane waves. > >> For infinite plane waves we would actually need infinitely large antennas. > > > > Irrelevant. The wave is given by the formula and is idealised to > > fill the entire space. Just like point masses are idealised to "anti-fill" > > only a single point. > How far do you want to stretch that 'idealisation'? > > Actually plane waves are only valid as local approximation. Yes, and it's a local result we're after (Doppler, Snell, etc.) > >> So, in total, plane waves are only usable as local approximation to > >> real world waves, which are more or less spherical. > > > > Yes. Plane waves are idealisations of spherical waves with a source > > as far as we please to satisfy any assumed marginof error. > But still plane waves are not real. The real waves stem from a certain > source and distribute spherically from there. Neitherare point masses and charges. Even the concept of derivative (like velocity and acceleration) uses an idealisation (a vanishingly small intervalof the independent variable). Are you going to deny calculus too? If yes, just say so, so we can finish this thread quickly. > >>>>> K is fixed. Reread the beginning of the paper. And obviously for the > >>>>> Doppler calculation it must be fixed since Einstein wants to see how > >>>>> the result depends on the angle phi of the wave direction. > >>>> What do you mean with 'fixed'??? > >>> > >>> Just fixed. Not changing once it was selected in Section 3. > >> Well, ok. > >> > >> But what difference does it make, if I chose the coordinate system prior > >> to the experiment or afterwards? > > > > It was you who made a big deal out of changing the system (rotating it, etc.) > > and it would supposedly render useless labelling space points using it. > > So Ipointed out that throughout Section 7 the syetm K is presumed unchanging, > > so that spatial points and time instants possess unambiguous coordinate labels. > I wanted to express, that I think, the coordinates in respect to the > observer are irrelevant. > > As proof I have 'relocated' the system (as 'thought experiment'). Since > the change of the coordinates would not change the field at that point, > the coordinates are irrelevant for the point and the wave. > >>> BTW, I don't know if you realise this, but this conversation is getting > >>> positively surreal. > >> Not more surreal than most other discussions here. > > > > No, I'd say a bit more. Here you are approaching Archimedes Plutonium > > levels of what (in his case) is basically the entire structure of thought > > process falling apart. You are not quite there yet :-) > You mean 'Androcles' ??? No, it's a guy at sci.math, he's been there for decades, he pretty much ruined that forum. He is an interesting case, probably a mild schizophrenic, he is originally, I think, a German speaker, born Ludwig Pohlmann but he changed his name several times, finally arriving at "Archimedes Plutonium". AFAIK it's his real, legal, name today. He is probably around 70 now and his math and logic is complete fantasyland. For example, he claims ellipse is not a conic section and the sine wave is a sequence of circles (or parabolas or something other, I forget). He is an interesting full-blown psychiatric case. In the 1990s he used to send e-mails to my employer to shut me up. Fun days :-) -- Jan
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| From | Urbano Stilo <nuor@riotlaur.iu> |
|---|---|
| Date | 2022-10-08 03:37 +0000 |
| Message-ID | <thqr9j$41ku$3@dont-email.me> |
| In reply to | #593035 |
JanPB wrote: > On Thursday, October 6, 2022 at 10:21:33 PM UTC-7, Thomas Heger wrote: >> Engineers say: "Sorry, but we cannot place antennas at infinity" > > But this is simply irrelevant, no matter who you are. The problem is to > find a formula for the Doppler shift. The simplifying assumption is > that the wave is a plane one. The reason is that the error due to > making this nonsense, your apparently are bombing natural gas pipelines under the sea, and germans are freezing and starving because of you.
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| From | Thomas Heger <ttt_heg@web.de> |
|---|---|
| Date | 2022-10-08 08:19 +0200 |
| Message-ID | <jqcj3aFfa54U1@mid.individual.net> |
| In reply to | #593035 |
Am 07.10.2022 um 23:14 schrieb JanPB: >>>>> Yes. And the emitter is at infinity. In fact the emitter is unimportant, >>>>> we only are interested in the wave it generates here. It's presumed >>>>> plane which is a limiting case putting the emitter at infinity. >>>> No, the emitter should NOT be at infinity! >>> >>> It must be because the waves are planar. But it makes no differnece where >>> it is anyway. Only the waves are important to express the Doppler >>> question fully. >> You think as a physicist and I as an engineer. >> >> Engineers say: "Sorry, but we cannot place antennas at infinity" > > But this is simply irrelevant, no matter who you are. The problem is > to find a formula for the Doppler shift. The simplifying assumption > is that the wave is a plane one. The reason is that the error due > to making this assumption can be made arbitrarily small by moving > the source as far as needed to cover the error. So regardless of > who you are, you simply make things obvious and simple by > assuming an ideal plane wave, secure in the knowledge that > the actual shift will differ by a vanishingly small number. > And e.g. distant stars are... well, DISTANT already anyway :-) > >> Physicsts say: "Inifinity is required, because we want plane waves" > > But this is just an idealisation, engineers do it all the time. No!! Engineers don't use idealisations all the time! Engineers build things, that really work (at least they try). An enigineer would never use infinity in an equation (if possible). But at least an engineer would not try to go there or place an antenna there. >>> The location of the source is not used. Besides, it's merely a limiting >>> case of a faraway source. Again, none of this is relevant. >> How can you say 'The location of the source is not used. ' ??? > > It just isn't. What's needed to calculate the Doppler effect is the > wave's frequency and direction. Usually we use wavelength in connection to the Doppler effect of light. So approaching sources get blue-shiften and receeding ones redshifted. This is a change of the wavelength. Wavelength is much more often used in connection to light, because the frequency of light in the THz range is very difficult to measure. >> 'The location of the source' is actually used, while the location of the >> observer or the center of the coordinate system K is not. > > The location of the source is not used besides the obvious > assumption that in real life it would have to be far away > enough to make the resulting wave a plane one over the > region being experimented with. This line of arguments 'flattens' me! Plane waves are a local approximation to begin with and do not really occur in natur. To get rid of this restriction, you want to allow to place the emitter at infinity??? > Thus for calculation one can simply assume the limiting > ideal case with the waves perfectly planar. This is done all > the time. Have you ever done any physics? Like deriving > Fresnel laws or Snell's law? You confuse math and physics. Mathematically you are right and can assume, what is known to be non-existent. But physics is a natural science and you cannot use infinity as you cannot use faries. > As for the location of the K-observer, it's not assumed he is > at the origin. All the formulas in Section 7 are valid at any > location, it does not have to be the origin. Not quite. If you want to have an observer away from the center of the coordinate system, you could leave the observer away entirely, if his position is undefined. And you leave coordinate system K away, too, as that serves no obvious purpose anymore. >>>> For instance: an emitter at infinity cannot send a signal here, because >>>> that would take infinite time to travel. >>> >>> Again, it's a limit and it's also irrelevant. Point masses don't >>> exist either yet nobody is negating Newtonian mechanics because >>> of that. Those are simple, well-understood limits. They are in >>> this case irrelevant anyway. >> I have actually criticised the use of the term 'point mass' in >> Einstein's text, too. >> >> Mass is an attribute of 3-dimensional objects, while points have zero. > > Yes, but Newton and Maxwell and everyone else uses them for obvious > reasons. Of course it is not _a priori_ clear that point masses or point > charges are not contradictory within the actual theories they are a part > of but the fact is they are not. As everyting else in science AND > engineering, they are a very good idealisations which yield results > for real (extended) masses and charges. > >>>> As infitely far distance of the emitter would reduce the signal strength >>>> to zero, we could measure no signals from there, neither. >>> >>> Irrelevant. We assume the wave is as described by the formula. >> To use infinity is a really bad idea. > > Why? It's like point masses and charges. It's simply an approximation > of a faraway source, with the added capability of making the approximation > error arbitrarily small. This is a HUGE practical and theoretical advantage. > We are talking 18th century stuff here. Why you cannot use 'inf' as a reference point??? The answer is simply this equation from my 'inf algebra': inf - r = inf (for all r of R) This would make it practically impossible to move in respect to infinity. >> Einstein used this idea, too. And I had mentioned, that velocity in >> respect to infinity is always zero. > > Irrelevant. No. It is actually relevant, if a statement is about a possible situation or about an impossible one. If you allow pigs with wings, then everything is possible. ... TH
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| From | Volney <volney@invalid.invalid> |
|---|---|
| Date | 2022-10-08 03:37 -0400 |
| Message-ID | <thr9ar$55fc$1@dont-email.me> |
| In reply to | #593072 |
On 10/8/2022 2:19 AM, Thomas Heger wrote: > Am 07.10.2022 um 23:14 schrieb JanPB: > >>>>>> Yes. And the emitter is at infinity. In fact the emitter is >>>>>> unimportant, >>>>>> we only are interested in the wave it generates here. It's presumed >>>>>> plane which is a limiting case putting the emitter at infinity. >>>>> No, the emitter should NOT be at infinity! >>>> >>>> It must be because the waves are planar. But it makes no differnece >>>> where >>>> it is anyway. Only the waves are important to express the Doppler >>>> question fully. >>> You think as a physicist and I as an engineer. >>> >>> Engineers say: "Sorry, but we cannot place antennas at infinity" >> >> But this is simply irrelevant, no matter who you are. The problem is >> to find a formula for the Doppler shift. The simplifying assumption >> is that the wave is a plane one. The reason is that the error due >> to making this assumption can be made arbitrarily small by moving >> the source as far as needed to cover the error. So regardless of >> who you are, you simply make things obvious and simple by >> assuming an ideal plane wave, secure in the knowledge that >> the actual shift will differ by a vanishingly small number. >> And e.g. distant stars are... well, DISTANT already anyway :-) >> >>> Physicsts say: "Inifinity is required, because we want plane waves" >> >> But this is just an idealisation, engineers do it all the time. > > No!! > > Engineers don't use idealisations all the time! They certainly do! In this case they'd say: "Let there be a plane wave..." > > Engineers build things, that really work (at least they try). > > An enigineer would never use infinity in an equation (if possible). And nobody needs to use infinity anywhere. An engineer would simply say: "Let there be a plane wave." No need to mention how a plane wave could have gotten there, how to create one, infinite this or that, there simply is a plane wave. Deal with it. > > But at least an engineer would not try to go there or place an antenna > there. > Nope. "Let there be a plane wave." End of discussion about where it came from. Because it's simply not important. There is simply a plane wave. >>>> The location of the source is not used. Besides, it's merely a limiting >>>> case of a faraway source. Again, none of this is relevant. >>> How can you say 'The location of the source is not used. ' ??? >> >> It just isn't. What's needed to calculate the Doppler effect is the >> wave's frequency and direction. > > > Usually we use wavelength in connection to the Doppler effect of light. And if it's a radio wave? (and why would it matter? Frequency is c/wavelength) > > So approaching sources get blue-shiften and receeding ones redshifted. > > This is a change of the wavelength. > > Wavelength is much more often used in connection to light, because the > frequency of light in the THz range is very difficult to measure. Who cares? F=c/lambda. > >>> 'The location of the source' is actually used, while the location of the >>> observer or the center of the coordinate system K is not. >> >> The location of the source is not used besides the obvious >> assumption that in real life it would have to be far away >> enough to make the resulting wave a plane one over the >> region being experimented with. > > > This line of arguments 'flattens' me! > > Plane waves are a local approximation to begin with and do not really > occur in natur. Neither do point charges, frictionless pulleys, massless ropes and other approximations often use to make a problem easier in physics. These are used because it makes the problem much easier. > > To get rid of this restriction, you want to allow to place the emitter > at infinity??? Nobody cares about any infinity. "Let there be a plane wave..." > > >> Thus for calculation one can simply assume the limiting >> ideal case with the waves perfectly planar. This is done all >> the time. Have you ever done any physics? Like deriving >> Fresnel laws or Snell's law? > > > You confuse math and physics. > > Mathematically you are right and can assume, what is known to be > non-existent. > > But physics is a natural science and you cannot use infinity as you > cannot use faries. Nobody is using any infinities. A simplification is used to make the problem easier to solve. As in: "Let there be a plane wave." >>>>> As infitely far distance of the emitter would reduce the signal >>>>> strength >>>>> to zero, we could measure no signals from there, neither. >>>> >>>> Irrelevant. We assume the wave is as described by the formula. >>> To use infinity is a really bad idea. >> >> Why? It's like point masses and charges. It's simply an approximation >> of a faraway source, with the added capability of making the >> approximation >> error arbitrarily small. This is a HUGE practical and theoretical >> advantage. >> We are talking 18th century stuff here. > > > Why you cannot use 'inf' as a reference point??? No reason to. That makes the problem complex. > > The answer is simply this equation from my 'inf algebra': > > inf - r = inf (for all r of R) > > This would make it practically impossible to move in respect to infinity. So it would be insane to use that. > >>> Einstein used this idea, too. And I had mentioned, that velocity in >>> respect to infinity is always zero. >> >> Irrelevant. > > No. > > It is actually relevant, if a statement is about a possible situation or > about an impossible one. Nobody is going to make a velocity with respect to infinity. Insane. > > If you allow pigs with wings, then everything is possible. Irrelevant.
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| From | JanPB <filmart@gmail.com> |
|---|---|
| Date | 2022-10-08 14:29 -0700 |
| Message-ID | <864b6d71-f733-4ea8-be81-8507c486f70cn@googlegroups.com> |
| In reply to | #593075 |
On Saturday, October 8, 2022 at 12:37:02 AM UTC-7, Volney wrote: > On 10/8/2022 2:19 AM, Thomas Heger wrote: > > Am 07.10.2022 um 23:14 schrieb JanPB: > > > >> But this is just an idealisation, engineers do it all the time. > > > > No!! > > > > Engineers don't use idealisations all the time! > > They certainly do! In this case they'd say: "Let there be a plane wave..." That's an even better way of putting it! -- Jan
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| From | Michel Marconi <iinc@lcrallem.or> |
|---|---|
| Date | 2022-10-08 22:21 +0000 |
| Message-ID | <thst63$9ges$1@dont-email.me> |
| In reply to | #593130 |
JanPB wrote: > On Saturday, October 8, 2022 at 12:37:02 AM UTC-7, Volney wrote: >> On 10/8/2022 2:19 AM, Thomas Heger wrote: >> > Am 07.10.2022 um 23:14 schrieb JanPB: >> >> But this is just an idealisation, engineers do it all the time. >> > >> > No!! Engineers don't use idealisations all the time! >> >> They certainly do! In this case they'd say: "Let there be a plane >> wave..." > > That's an even better way of putting it! idiots. Engineers are not saying anything. They build things. With models, but not necessary based on theories. Theories always comes later on.
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| From | Thomas Heger <ttt_heg@web.de> |
|---|---|
| Date | 2022-10-10 08:37 +0200 |
| Message-ID | <jqhssiF9u3hU1@mid.individual.net> |
| In reply to | #593130 |
Am 08.10.2022 um 23:29 schrieb JanPB: > On Saturday, October 8, 2022 at 12:37:02 AM UTC-7, Volney wrote: >> On 10/8/2022 2:19 AM, Thomas Heger wrote: >>> Am 07.10.2022 um 23:14 schrieb JanPB: >>> >>>> But this is just an idealisation, engineers do it all the time. >>> >>> No!! >>> >>> Engineers don't use idealisations all the time! >> >> They certainly do! In this case they'd say: "Let there be a plane wave..." > > That's an even better way of putting it! Einstein wanted to derive from a certain assumption an equation for the behavior of waves, seen by a moving observer. I have criticised Einstein's assumption, because his equations did not fit to his setting. Let me illustrate this setting a in a 'linguistic picture': we assume a box, which is filled with a plane wave. This wave is plane, sinosoidal with constant frequency, coming parallel from some unmentioned source with constant intensity and hits our box at a certin angle, which we can adjust. The intensity is constant from source to the other end of infinity and the wave is not spreading out forever. These assumption were quite unrealistic, but somehow possible. What was not possible, however, that was the use of positions in the equations. The reason: in this setting the box could be moved around and nothing would change, because the wave is infinitely homogenous, non degrading and parallel. If real spherical waves and a finite distance to the emitter were used, the equations could not be used anymore. For instance the angle of the incoming wave would change, if you move in respect to the source. Also the distance to the emitter would make a difference, because of some inverse square law. TH
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| From | JanPB <filmart@gmail.com> |
|---|---|
| Date | 2022-10-10 01:56 -0700 |
| Message-ID | <3f29d6a8-278d-4922-9245-dabb3ee556f6n@googlegroups.com> |
| In reply to | #593210 |
On Sunday, October 9, 2022 at 11:37:11 PM UTC-7, Thomas Heger wrote: > Am 08.10.2022 um 23:29 schrieb JanPB: > > On Saturday, October 8, 2022 at 12:37:02 AM UTC-7, Volney wrote: > >> On 10/8/2022 2:19 AM, Thomas Heger wrote: > >>> Am 07.10.2022 um 23:14 schrieb JanPB: > >>> > >>>> But this is just an idealisation, engineers do it all the time. > >>> > >>> No!! > >>> > >>> Engineers don't use idealisations all the time! > >> > >> They certainly do! In this case they'd say: "Let there be a plane wave..." > > > > That's an even better way of putting it! > Einstein wanted to derive from a certain assumption an equation for the > behavior of waves, seen by a moving observer. > > I have criticised Einstein's assumption, because his equations did not > fit to his setting. > > Let me illustrate this setting a in a 'linguistic picture': > > we assume a box, which is filled with a plane wave. This wave is plane, > sinosoidal with constant frequency, coming parallel from some > unmentioned source with constant intensity and hits our box at a certin > angle, which we can adjust. > > The intensity is constant from source to the other end of infinity and > the wave is not spreading out forever. > > These assumption were quite unrealistic, but somehow possible. It's a very realistic approximation, with an error that can be reduced arbitrarily. Plane waves are used all the time, it's a standard tool. > What was not possible, however, that was the use of positions in the > equations. > > The reason: in this setting the box could be moved around and nothing > would change, because the wave is infinitely homogenous, non degrading > and parallel. > > If real spherical waves and a finite distance to the emitter were used, > the equations could not be used anymore. True but the error can be made as small as we please by positioning the source far enough. Moreover, the idea here is to calculate the "pure" Doppler effect in which the distance to the source and the details of the shape of the wavefront do not contaminate the formula. So for sources like stars the formula would work FAPP perfectly. -- Jan
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| From | Thomas Heger <ttt_heg@web.de> |
|---|---|
| Date | 2022-10-11 08:03 +0200 |
| Message-ID | <jqkfa8Fm5e1U1@mid.individual.net> |
| In reply to | #593217 |
Am 10.10.2022 um 10:56 schrieb JanPB: >> Let me illustrate this setting a in a 'linguistic picture': >> >> we assume a box, which is filled with a plane wave. This wave is plane, >> sinosoidal with constant frequency, coming parallel from some >> unmentioned source with constant intensity and hits our box at a certin >> angle, which we can adjust. >> >> The intensity is constant from source to the other end of infinity and >> the wave is not spreading out forever. >> >> These assumption were quite unrealistic, but somehow possible. > > It's a very realistic approximation, with an error that can be reduced > arbitrarily. Plane waves are used all the time, it's a standard tool. Sure, but waves are usually not plane. This is Huygens principle, and plane waves require (almost) infinite antennas. https://en.wikipedia.org/wiki/Huygens%E2%80%93Fresnel_principle >> What was not possible, however, that was the use of positions in the >> equations. >> >> The reason: in this setting the box could be moved around and nothing >> would change, because the wave is infinitely homogenous, non degrading >> and parallel. >> >> If real spherical waves and a finite distance to the emitter were used, >> the equations could not be used anymore. > > True but the error can be made as small as we please by positioning the > source far enough. Moreover, the idea here is to calculate the "pure" Doppler > effect in which the distance to the source and the details of the shape of > the wavefront do not contaminate the formula. So for sources like stars > the formula would work FAPP perfectly. I do agree, of course. But my point was, that the term 1/c (l*x + m*y + n*z) in Einstein's equation was wrong. The reason is, that the introduction of these coordinates and direction cosines cannot possibly have an effect upon the wave and the effect of this wave on the fields at a point. So, I stumpled upon this term and found no use for it, because I was unable to identify a related process. Einstein made the additional error to give no hints about his intentions. So the text had a narrative structure similar to painting with dots and requesting the reader to fill in the gaps. In my view, this is wrong, because an author should tell his story and make statements explicit. TH >
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| From | JanPB <filmart@gmail.com> |
|---|---|
| Date | 2022-10-11 01:06 -0700 |
| Message-ID | <69e50897-91a0-4ef5-813b-9bbd640c8e38n@googlegroups.com> |
| In reply to | #593268 |
On Monday, October 10, 2022 at 11:03:57 PM UTC-7, Thomas Heger wrote: > Am 10.10.2022 um 10:56 schrieb JanPB: > > >> Let me illustrate this setting a in a 'linguistic picture': > >> > >> we assume a box, which is filled with a plane wave. This wave is plane, > >> sinosoidal with constant frequency, coming parallel from some > >> unmentioned source with constant intensity and hits our box at a certin > >> angle, which we can adjust. > >> > >> The intensity is constant from source to the other end of infinity and > >> the wave is not spreading out forever. > >> > >> These assumption were quite unrealistic, but somehow possible. > > > > It's a very realistic approximation, with an error that can be reduced > > arbitrarily. Plane waves are used all the time, it's a standard tool. > Sure, but waves are usually not plane. > > This is Huygens principle, and plane waves require (almost) infinite > antennas. Yes but this is irrelevant. Here we want to calculate the Doppler effect at a specified frequency and direction. The directions is idealised to be fixed, i.e. the source is presumed as distant as we please. > >> What was not possible, however, that was the use of positions in the > >> equations. > >> > >> The reason: in this setting the box could be moved around and nothing > >> would change, because the wave is infinitely homogenous, non degrading > >> and parallel. > >> > >> If real spherical waves and a finite distance to the emitter were used, > >> the equations could not be used anymore. > > > > True but the error can be made as small as we please by positioning the > > source far enough. Moreover, the idea here is to calculate the "pure" Doppler > > effect in which the distance to the source and the details of the shape of > > the wavefront do not contaminate the formula. So for sources like stars > > the formula would work FAPP perfectly. > I do agree, of course. > > But my point was, that the term 1/c (l*x + m*y + n*z) in Einstein's > equation was wrong. This is not any "Einstein equation", is a standard plane wave formula. I'm not a historian but I'm reasonably certain it's at least as old as, say, Fresnel or Laplace. > The reason is, that the introduction of these coordinates and direction > cosines cannot possibly have an effect upon the wave and the effect of > this wave on the fields at a point. This formula defines a plane wave in all space with a specified direction, speed, frequency, and (obviously) values (vector values in this case). > So, I stumpled upon this term and found no use for it, because I was > unable to identify a related process. Pick a physics textbook. > Einstein made the additional error to give no hints about his intentions. Again: the intent is obvious. In a science paper one simply never defines elementary concepts taught in high school. > So the text had a narrative structure similar to painting with dots and > requesting the reader to fill in the gaps. No, false. > In my view, this is wrong, because an author should tell his story and > make statements explicit. This is just silly. -- Jan
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| From | Maciej Wozniak <maluwozniak@gmail.com> |
|---|---|
| Date | 2022-10-11 01:25 -0700 |
| Message-ID | <43b747e0-436d-42aa-bb7f-44694a694d03n@googlegroups.com> |
| In reply to | #593275 |
On Tuesday, 11 October 2022 at 10:06:24 UTC+2, JanPB wrote: > Again: the intent is obvious. In a science paper one simply never defines > elementary concepts taught in high school. And - up to the time of your idiot guru - one never was stupid enough to ignore or reject them.
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| From | Thomas Heger <ttt_heg@web.de> |
|---|---|
| Date | 2022-10-12 08:17 +0200 |
| Message-ID | <jqn4foF497vU1@mid.individual.net> |
| In reply to | #593275 |
Am 11.10.2022 um 10:06 schrieb JanPB: > On Monday, October 10, 2022 at 11:03:57 PM UTC-7, Thomas Heger wrote: >> Am 10.10.2022 um 10:56 schrieb JanPB: >> >>>> Let me illustrate this setting a in a 'linguistic picture': >>>> >>>> we assume a box, which is filled with a plane wave. This wave is plane, >>>> sinosoidal with constant frequency, coming parallel from some >>>> unmentioned source with constant intensity and hits our box at a certin >>>> angle, which we can adjust. >>>> >>>> The intensity is constant from source to the other end of infinity and >>>> the wave is not spreading out forever. >>>> >>>> These assumption were quite unrealistic, but somehow possible. >>> >>> It's a very realistic approximation, with an error that can be reduced >>> arbitrarily. Plane waves are used all the time, it's a standard tool. >> Sure, but waves are usually not plane. >> >> This is Huygens principle, and plane waves require (almost) infinite >> antennas. > > Yes but this is irrelevant. Here we want to calculate the Doppler effect > at a specified frequency and direction. The directions is idealised to > be fixed, i.e. the source is presumed as distant as we please. > >>>> What was not possible, however, that was the use of positions in the >>>> equations. >>>> >>>> The reason: in this setting the box could be moved around and nothing >>>> would change, because the wave is infinitely homogenous, non degrading >>>> and parallel. >>>> >>>> If real spherical waves and a finite distance to the emitter were used, >>>> the equations could not be used anymore. >>> >>> True but the error can be made as small as we please by positioning the >>> source far enough. Moreover, the idea here is to calculate the "pure" Doppler >>> effect in which the distance to the source and the details of the shape of >>> the wavefront do not contaminate the formula. So for sources like stars >>> the formula would work FAPP perfectly. >> I do agree, of course. >> >> But my point was, that the term 1/c (l*x + m*y + n*z) in Einstein's >> equation was wrong. > > This is not any "Einstein equation", is a standard plane wave formula. https://atmos.washington.edu/~hakim/542/wave_properties.pdf Notice, please, that Einstein's setting was different. Einstein considered incoming waves at a certain point (coming from a distant source), while the equations in the link above mean the relation in respect to the source. In the standard setting, the wave moves away from the center of the coordinate system, while in Einstein's setting a certain point is observed from there. The difference is, that the observer does not create the waves, hence has only a passive role. Therefore his position is irrelevant for the wave and the points it hits, because observation is not supposed to alter the fields at remote points. ... TH
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| From | Maciej Wozniak <maluwozniak@gmail.com> |
|---|---|
| Date | 2022-10-11 23:32 -0700 |
| Message-ID | <97828f3e-85bf-4db7-a60a-1e5b5d948194n@googlegroups.com> |
| In reply to | #593328 |
On Wednesday, 12 October 2022 at 08:17:33 UTC+2, Thomas Heger wrote: > Am 11.10.2022 um 10:06 schrieb JanPB: > > On Monday, October 10, 2022 at 11:03:57 PM UTC-7, Thomas Heger wrote: > >> Am 10.10.2022 um 10:56 schrieb JanPB: > >> > >>>> Let me illustrate this setting a in a 'linguistic picture': > >>>> > >>>> we assume a box, which is filled with a plane wave. This wave is plane, > >>>> sinosoidal with constant frequency, coming parallel from some > >>>> unmentioned source with constant intensity and hits our box at a certin > >>>> angle, which we can adjust. > >>>> > >>>> The intensity is constant from source to the other end of infinity and > >>>> the wave is not spreading out forever. > >>>> > >>>> These assumption were quite unrealistic, but somehow possible. > >>> > >>> It's a very realistic approximation, with an error that can be reduced > >>> arbitrarily. Plane waves are used all the time, it's a standard tool. > >> Sure, but waves are usually not plane. > >> > >> This is Huygens principle, and plane waves require (almost) infinite > >> antennas. > > > > Yes but this is irrelevant. Here we want to calculate the Doppler effect > > at a specified frequency and direction. The directions is idealised to > > be fixed, i.e. the source is presumed as distant as we please. > > > >>>> What was not possible, however, that was the use of positions in the > >>>> equations. > >>>> > >>>> The reason: in this setting the box could be moved around and nothing > >>>> would change, because the wave is infinitely homogenous, non degrading > >>>> and parallel. > >>>> > >>>> If real spherical waves and a finite distance to the emitter were used, > >>>> the equations could not be used anymore. > >>> > >>> True but the error can be made as small as we please by positioning the > >>> source far enough. Moreover, the idea here is to calculate the "pure" Doppler > >>> effect in which the distance to the source and the details of the shape of > >>> the wavefront do not contaminate the formula. So for sources like stars > >>> the formula would work FAPP perfectly. > >> I do agree, of course. > >> > >> But my point was, that the term 1/c (l*x + m*y + n*z) in Einstein's > >> equation was wrong. > > > > This is not any "Einstein equation", is a standard plane wave formula. > https://atmos.washington.edu/~hakim/542/wave_properties.pdf > > Notice, please, that Einstein's setting was different. > > Einstein considered incoming waves at a certain point (coming from a > distant source), while the equations in the link above mean the relation > in respect to the source. > In the standard setting, the wave moves away from the center of the > coordinate system, while in Einstein's setting a certain point is > observed from there. > > The difference is, that the observer does not create the waves, hence > has only a passive role. Sorry, apart of waves there are some more subjects involved in experiments. No, the observer has a very active role - it's just that your beloved physics is far, far too primitive to get it.
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