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Groups > sci.physics.relativity > #411547 > unrolled thread
| Started by | someone <glenn.spigel@googlemail.com> |
|---|---|
| First post | 2017-03-03 07:04 -0800 |
| Last post | 2017-04-08 12:28 -0700 |
| Articles | 20 on this page of 253 — 35 participants |
Back to article view | Back to sci.physics.relativity
Twin paradox someone <glenn.spigel@googlemail.com> - 2017-03-03 07:04 -0800
Re: Twin paradox Odd Bodkin <bodkinodd@gmail.com> - 2017-03-03 09:09 -0600
Re: Twin paradox someone <glenn.spigel@googlemail.com> - 2017-03-03 08:12 -0800
Re: Twin paradox Odd Bodkin <bodkinodd@gmail.com> - 2017-03-03 10:32 -0600
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-04 07:08 -0800
Re: Twin paradox rotchm <rotchm@gmail.com> - 2017-03-04 07:47 -0800
Re: Twin paradox "David (Lord Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2017-03-04 09:15 -0800
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-04 10:23 -0800
Re: Twin paradox Sylvia Else <sylvia@not.at.this.address> - 2017-03-05 11:42 +1100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-05 08:55 -0800
Re: Twin paradox wugi <brol@brol.be> - 2017-03-14 22:31 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-15 03:22 -0700
Re: Twin paradox wugi <brol@brol.be> - 2017-03-17 18:39 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-17 13:56 -0700
Re: Twin paradox wugi <brol@brol.be> - 2017-03-17 22:54 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-17 17:32 -0700
Re: Twin paradox wugi <brol@brol.be> - 2017-03-18 18:16 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-19 08:28 -0700
Re: Twin paradox wugi <brol@brol.be> - 2017-03-19 23:09 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-20 08:14 -0700
Re: Twin paradox Sylvia Else <sylvia@not.at.this.address> - 2017-03-19 13:05 +1100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-19 09:44 -0700
Re: Twin paradox wugi <brol@brol.be> - 2017-03-19 22:38 +0100
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-19 19:30 -0500
Re: Twin paradox Koobee Wublee <koobee.wublee@gmail.com> - 2017-03-19 22:41 -0700
Re: Twin paradox mlwozniak@wp.pl - 2017-03-20 00:29 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-20 08:59 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-21 10:53 -0500
Re: Twin paradox wugi <brol@brol.be> - 2017-03-21 18:59 +0100
Re: Twin paradox Sylvia Else <sylvia@not.at.this.address> - 2017-03-22 17:45 +1100
Re: Twin paradox wugi <brol@brol.be> - 2017-03-22 11:25 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-22 06:42 -0700
Re: Twin paradox Koobee Wublee <koobee.wublee@gmail.com> - 2017-03-22 00:26 -0700
Re: Twin paradox Sylvia Else <sylvia@not.at.this.address> - 2017-03-22 19:30 +1100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-22 07:56 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-22 05:49 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-22 06:17 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-22 08:20 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-22 11:08 -0800
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-22 11:41 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-22 11:51 -0800
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-22 12:02 -0800
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-23 07:06 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-29 11:24 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-27 13:50 -0500
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-28 06:18 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-28 12:13 -0500
Re: Twin paradox dickorrich@gmail.com - 2017-03-29 10:45 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-29 11:22 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-30 00:17 -0500
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-30 06:02 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-04-03 12:31 -0500
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-04 02:14 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-03 17:21 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-04-04 10:37 -0500
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-04 08:52 -0700
Re: Twin paradox Poutnik <poutnik4nntp@gmail.com> - 2017-04-04 18:51 +0200
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-05 02:39 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-20 08:36 -0700
Re: Twin paradox wugi <brol@brol.be> - 2017-03-20 17:27 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-20 10:49 -0700
Re: Twin paradox wugi <brol@brol.be> - 2017-03-20 21:10 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-20 16:59 -0700
Re: Twin paradox wugi <brol@brol.be> - 2017-03-21 12:37 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-21 06:13 -0700
Re: Twin paradox Gary Harnagel <hitlong@yahoo.com> - 2017-03-21 08:03 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-21 11:03 -0700
Re: Twin paradox "Dono," <sa_ge@comcast.net> - 2017-03-04 06:20 -0800
Re: Twin paradox Ed Lake <detect@newsguy.com> - 2017-03-04 09:41 -0800
Re: Twin paradox Odd Bodkin <bodkinodd@gmail.com> - 2017-03-05 14:59 -0600
Re: Twin paradox alsor@interia.pl - 2017-03-05 13:23 -0800
Re: Twin paradox Mike Fontenot <mlfasf@comcast.net> - 2017-03-07 09:46 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-07 10:10 -0800
Re: Twin paradox Mike Fontenot <mlfasf@comcast.net> - 2017-03-07 12:13 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-07 13:32 -0800
Re: Twin paradox Poutnik <poutnik4nntp@gmail.com> - 2017-03-08 07:58 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-08 09:09 -0800
Re: Twin paradox Poutnik <poutnik4nntp@gmail.com> - 2017-03-08 23:04 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-08 16:19 -0800
Re: Twin paradox John Heath <heathjohn2@gmail.com> - 2017-03-04 11:23 -0800
Re: Twin paradox "David (Lord Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2017-03-04 14:02 -0800
Re: Twin paradox someone <glenn.spigel@googlemail.com> - 2017-03-06 12:05 -0800
Re: Twin paradox John Heath <heathjohn2@gmail.com> - 2017-03-06 16:34 -0800
Re: Twin paradox "Paul B. Andersen" <relativity@paulba.no> - 2017-03-07 12:57 +0100
Re: Twin paradox John Heath <heathjohn2@gmail.com> - 2017-03-07 20:29 -0800
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-04 22:13 -0600
Re: Twin paradox Koobee Wublee <koobee.wublee@gmail.com> - 2017-03-09 12:58 -0800
Re: Twin paradox Odd Bodkin <bodkinodd@gmail.com> - 2017-03-10 07:25 -0600
Re: Twin paradox "David (Lord Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2017-03-10 13:21 -0800
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-05 08:44 -0800
Re: Twin paradox someone <glenn.spigel@googlemail.com> - 2017-03-06 12:03 -0800
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-06 18:02 -0800
Re: Twin paradox someone <glenn.spigel@googlemail.com> - 2017-03-07 14:15 -0800
Re: Twin paradox "Paul B. Andersen" <relativity@paulba.no> - 2017-03-05 21:31 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-05 15:09 -0800
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-05 15:18 -0800
Re: Twin paradox "Paul B. Andersen" <relativity@paulba.no> - 2017-03-06 23:10 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-10 11:39 -0800
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-13 09:53 -0500
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-13 08:33 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-14 10:50 -0500
Re: Twin paradox mlwozniak@wp.pl - 2017-03-15 00:43 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-15 04:08 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-16 16:48 -0500
Re: Twin paradox mlwozniak@wp.pl - 2017-03-17 01:01 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-17 07:40 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-18 14:16 -0500
Re: Twin paradox Idimi Higame <iumia@igmwwad.hh> - 2017-03-18 20:05 +0000
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-19 09:28 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-20 13:55 -0500
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-20 16:34 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-21 10:56 -0500
Re: Twin paradox Julio Di Egidio <julio@diegidio.name> - 2017-03-19 21:38 -0700
Re: Twin paradox Koobee Wublee <koobee.wublee@gmail.com> - 2017-03-19 22:52 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-21 00:14 -0800
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-21 13:43 -0800
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-22 01:39 -0800
Re: Twin paradox mlwozniak@wp.pl - 2017-03-22 01:52 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-22 11:12 -0800
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-22 11:56 -0800
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-22 12:06 -0800
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-15 04:16 -0700
Re: Twin paradox someone <glenn.spigel@googlemail.com> - 2017-03-06 09:34 -0800
Re: Twin paradox "Paul B. Andersen" <relativity@paulba.no> - 2017-03-06 23:01 +0100
Re: Twin paradox alsor@interia.pl - 2017-03-06 15:09 -0800
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-07 09:49 -0800
Re: Twin paradox someone <glenn.spigel@googlemail.com> - 2017-03-07 14:04 -0800
Re: Twin paradox "Paul B. Andersen" <relativity@paulba.no> - 2017-03-08 10:40 +0100
Re: Twin paradox someone <glenn.spigel@googlemail.com> - 2017-03-08 07:11 -0800
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-08 15:04 -0600
Re: Twin paradox someone <glenn.spigel@googlemail.com> - 2017-03-08 14:30 -0800
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-09 10:39 -0600
Re: Twin paradox someone <glenn.spigel@googlemail.com> - 2017-03-09 13:20 -0800
Re: Twin paradox Odd Bodkin <bodkinodd@gmail.com> - 2017-03-10 07:27 -0600
Re: Twin paradox someone <glenn.spigel@googlemail.com> - 2017-03-10 06:05 -0800
Re: Twin paradox Odd Bodkin <bodkinodd@gmail.com> - 2017-03-10 08:45 -0600
Re: Twin paradox alsor@interia.pl - 2017-03-14 13:19 -0700
Re: Twin paradox "Paul B. Andersen" <relativity@paulba.no> - 2017-03-10 11:49 +0100
Re: Twin paradox wugi <brol@brol.be> - 2017-03-17 17:37 +0100
Re: Twin paradox Julio Di Egidio <julio@diegidio.name> - 2017-03-19 21:33 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-03-20 09:05 -0700
Re: Twin paradox Koobee Wublee <koobee.wublee@gmail.com> - 2017-03-09 13:12 -0800
Re: Twin paradox Otplate Yuugaku <yu@yotwaglwt.pa> - 2017-03-09 22:50 +0000
Re: Twin paradox Dirk Van de moortel <dirkvandemoortel@hotspam.not> - 2017-03-10 11:01 +0100
Re: Twin paradox Koobee Wublee <koobee.wublee@gmail.com> - 2017-03-10 11:14 -0800
Re: Twin paradox Priscilla Groll <lloi@wgnprlw.sl> - 2017-03-11 17:27 +0000
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-04 06:13 -0700
Re: Twin paradox Hermelinda Riess <hsr@ermeemw.ei> - 2017-04-04 15:10 +0000
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-04 08:36 -0700
Re: Twin paradox Hermelinda Riess <hsr@ermeemw.ei> - 2017-04-04 17:51 +0000
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-05 02:52 -0700
Re: Twin paradox Hermelinda Riess <hsr@ermeemw.ei> - 2017-04-05 17:17 +0000
Re: Twin paradox numbernumber1964@gmail.com - 2017-03-05 13:31 -0800
Re: Twin paradox Julio Di Egidio <julio@diegidio.name> - 2017-03-08 14:17 -0800
Re: Twin paradox someone <glenn.spigel@googlemail.com> - 2017-03-08 14:34 -0800
Re: Twin paradox Julio Di Egidio <julio@diegidio.name> - 2017-03-08 15:32 -0800
Re: Twin paradox someone <glenn.spigel@googlemail.com> - 2017-03-09 13:20 -0800
Re: Twin paradox numbernumber1964@gmail.com - 2017-03-09 13:35 -0800
Re: Twin paradox Koobee Wublee <koobee.wublee@gmail.com> - 2017-03-12 00:07 -0800
Re: Twin paradox ronjresnick@gmail.com - 2017-03-13 13:58 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-14 10:28 -0500
Re: Twin paradox Koobee Wublee <koobee.wublee@gmail.com> - 2017-03-14 12:31 -0700
Re: Twin paradox "Kevin Aylward" <kevinRemovAT@kevinaylward.co.uk> - 2017-03-14 22:11 +0000
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-14 22:34 -0500
Re: Twin paradox Koobee Wublee <koobee.wublee@gmail.com> - 2017-03-15 00:46 -0700
Re: Twin paradox Koobee Wublee <koobee.wublee@gmail.com> - 2017-03-15 00:53 -0700
Re: Twin paradox Odd Bodkin <bodkinodd@gmail.com> - 2017-03-15 09:19 -0500
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-16 23:50 -0800
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-16 23:54 -0800
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-17 08:15 -0800
Re: Twin paradox "David (Lord Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2017-03-17 09:03 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-18 18:37 -0800
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-03-19 00:20 -0800
Re: Twin paradox Odd Bodkin <bodkinodd@gmail.com> - 2017-03-15 09:15 -0500
Re: Twin paradox rotchm <rotchm@gmail.com> - 2017-03-15 07:54 -0700
Re: Twin paradox Julio Di Egidio <julio@diegidio.name> - 2017-03-15 02:53 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-15 15:18 -0500
Re: Twin paradox Koobee Wublee <koobee.wublee@gmail.com> - 2017-03-19 22:43 -0700
Re: Twin paradox mlwozniak@wp.pl - 2017-03-15 03:22 -0700
Re: Twin paradox "Kevin Aylward" <kevinRemovAT@kevinaylward.co.uk> - 2017-03-15 21:31 +0000
Re: Twin paradox alsor@interia.pl - 2017-03-16 16:56 -0700
Re: Twin paradox mlwozniak@wp.pl - 2017-03-15 00:41 -0700
Re: Twin paradox Ron Resnick <ronjresnick@gmail.com> - 2017-03-15 03:09 -0700
Re: Twin paradox rotchm <rotchm@gmail.com> - 2017-03-15 08:02 -0700
Re: Twin paradox "Kevin Aylward" <kevinRemovAT@kevinaylward.co.uk> - 2017-03-14 22:10 +0000
Re: Twin paradox rotchm <rotchm@gmail.com> - 2017-03-15 07:41 -0700
Re: Twin paradox Odd Bodkin <bodkinodd@gmail.com> - 2017-03-15 10:02 -0500
Re: Twin paradox numbernumber1964@gmail.com - 2017-03-14 11:19 -0700
Re: Twin paradox numbernumber1964@gmail.com - 2017-03-18 11:51 -0700
Re: Twin paradox numbernumber1964@gmail.com - 2017-03-18 14:13 -0700
Twin paradox "David (Lord Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2017-03-19 09:26 -0700
Twin paradox "David (Lord Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2017-03-19 09:53 -0700
Re: Twin paradox numbernumber1964@gmail.com - 2017-03-19 12:59 -0700
Re: Twin paradox numbernumber1964@gmail.com - 2017-03-20 10:29 -0700
Re: Twin paradox numbernumber1964@gmail.com - 2017-03-22 09:40 -0700
Re: Twin paradox numbernumber1964@gmail.com - 2017-03-22 09:44 -0700
Re: Twin paradox numbernumber1964@gmail.com - 2017-03-22 14:32 -0700
Re: Twin paradox Deon Joubert <dhjoubert@gmail.com> - 2017-03-30 09:27 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-30 23:34 -0500
Re: Twin paradox Deon Joubert <dhjoubert@gmail.com> - 2017-03-31 00:33 -0700
Re: Twin paradox Deon Joubert <dhjoubert@gmail.com> - 2017-03-31 02:43 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-03-31 21:43 -0500
Re: Twin paradox mlwozniak@wp.pl - 2017-04-01 00:52 -0700
Re: Twin paradox Deon Joubert <dhjoubert@gmail.com> - 2017-04-01 01:41 -0700
Re: Twin paradox Domonique Corle <oreuni@wwerwo.co> - 2017-04-01 13:01 +0000
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-04-01 10:27 -0500
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-01 20:44 -0800
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-03 00:05 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-03 00:28 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-03 04:14 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-03 17:15 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-04 11:47 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-04 05:57 -0700
Re: Twin paradox Paparios <mrios@ing.puc.cl> - 2017-04-04 07:05 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-04 07:43 -0700
Re: Twin paradox Paparios <mrios@ing.puc.cl> - 2017-04-04 09:20 -0700
Re: Twin paradox "David (Lord Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2017-04-04 09:58 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-05 02:25 -0700
Re: Twin paradox Paparios <mrios@ing.puc.cl> - 2017-04-05 04:22 -0700
Re: Twin paradox mlwozniak@wp.pl - 2017-04-05 06:23 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-05 09:58 -0700
Re: Twin paradox Paparios <mrios@ing.puc.cl> - 2017-04-05 10:21 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-05 11:36 -0700
Re: Twin paradox Hermelinda Riess <hsr@ermeemw.ei> - 2017-04-04 15:01 +0000
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-05 00:32 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-05 02:55 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-07 21:32 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-08 07:38 -0700
Re: Twin paradox Tom Roberts <tjroberts137@sbcglobal.net> - 2017-04-08 10:31 -0500
Re: Twin paradox mlwozniak@wp.pl - 2017-04-08 08:42 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-09 14:29 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-10 22:18 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-11 06:11 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-12 00:13 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-12 07:00 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-12 14:49 -0700
Re: Twin paradox Ned Latham <nedlatham@woden.valhalla.oz> - 2017-04-13 09:44 +0000
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-13 06:03 -0700
Re: Twin paradox Ned Latham <nedlatham@woden.valhalla.oz> - 2017-04-13 20:40 +0000
Re: Twin paradox "Kevin Aylward" <kevinRemovAT@kevinaylward.co.uk> - 2017-04-14 10:42 +0100
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-14 08:27 -0700
Re: Twin paradox Gary Harnagel <hitlong@yahoo.com> - 2017-04-16 05:49 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-17 08:05 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-17 08:22 -0700
Re: Twin paradox Nocasto Aboyar <oocaao@syeoby.ao> - 2017-04-17 15:36 +0000
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-17 09:08 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-17 10:45 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-17 10:56 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-19 10:14 -0700
Re: Twin paradox Jonathan Doolin <good4usoul@gmail.com> - 2017-04-20 08:48 -0700
Re: Twin paradox mlwozniak@wp.pl - 2017-04-17 08:52 -0700
Re: Twin paradox The Starmaker <starmaker@ix.netcom.com> - 2017-04-08 09:51 -0700
Re: Twin paradox "David (Lord Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2017-04-08 12:28 -0700
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| From | someone <glenn.spigel@googlemail.com> |
|---|---|
| Date | 2017-03-03 07:04 -0800 |
| Subject | Twin paradox |
| Message-ID | <84b17e46-6e16-425b-a222-a8afdd5d2e58@googlegroups.com> |
The twin paradox is as I understand it that there are twins, and one goes off in a spaceship, and as it does from its perspective the other twins clock is going slower, but from the twin on Earths perspective the twin going off in a spaceships clock is going slower. But when they come back to meet it cannot be that both clocks were going slower. It is then claimed that the one that was on the spaceship will be the one that aged for some reason. https://en.wikipedia.org/wiki/Twin_paradox states: --- Max von Laue argued in 1913 that since the traveling twin must be in two separate inertial frames, one on the way out and another on the way back, this frame switch is the reason for the aging difference, not the acceleration per se.[7] Explanations put forth by Albert Einstein and Max Born invoked gravitational time dilation to explain the aging as a direct effect of acceleration.[8] --- But wouldn't the amount of ageing be dependent on how far the spaceship was travelling at constant velocity once it had reached it, and wouldn't there be hardly any gravitational time dilation at that point (assuming it is at a suitable distance away from any objects of significant mass and undergoing no proper acceleration)? Also what difference is it supposed to make to the relevant ageing whether the ship turns back or not? Lastly supposing the twin in the spaceship had taken off from some giant Death Star type structure, and had been in some unconscious in some sleep inducing machine at takeoff until a day before the spaceship was to turn around. And that an hour after the twin awakes it passes another spaceship with a person on board which had also just awaken. Their ships would pass, and if neither knew what their ship's program was, neither would be able to tell who was moving. But imagine that the second ship was at rest with the Death Star structure. So both could be thinking that the other's clock was running slower than its own, if they thought it was all relative, but wouldn't the one in the ship at rest with the Death Star be wrong (the clock on the ship that had left earth was going slower relative to any clock in the Death Star's restframe)?
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| From | Odd Bodkin <bodkinodd@gmail.com> |
|---|---|
| Date | 2017-03-03 09:09 -0600 |
| Message-ID | <o9c0v2$1aur$1@gioia.aioe.org> |
| In reply to | #411547 |
On 3/3/2017 9:04 AM, someone wrote: > The twin paradox is as I understand it that there are twins, and one goes off in a spaceship, and as > it does from its perspective the other twins clock is going slower, but from the twin on Earths > perspective the twin going off in a spaceships clock is going slower. But when they come back to > meet it cannot be that both clocks were going slower. It is then claimed that the one that was on > the spaceship will be the one that aged for some reason. https://en.wikipedia.org/wiki/Twin_paradox states: In the description above you have laid bare a lot of the misconceptions about relativity that this puzzle was explicitly designed to illuminate. Among these misconceptions are: - That the experiences of the two twins are symmetric - That both twins will see the other's clock as being behind throughout the whole trip - That this puzzle is an example of inertial motion throughout - That time dilation is all about clocks running slower and nothing else (missing completely the point about synchronization being frame-dependent) -- Odd Bodkin -- maker of fine toys, tools, tables
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| From | someone <glenn.spigel@googlemail.com> |
|---|---|
| Date | 2017-03-03 08:12 -0800 |
| Message-ID | <3e17e0da-f87a-4c37-b128-7b4f27842a1a@googlegroups.com> |
| In reply to | #411549 |
On Friday, March 3, 2017 at 3:09:25 PM UTC, Odd Bodkin wrote: > On 3/3/2017 9:04 AM, someone wrote: > > The twin paradox is as I understand it that there are twins, and one goes off in a spaceship, and as > > it does from its perspective the other twins clock is going slower, but from the twin on Earths > > perspective the twin going off in a spaceships clock is going slower. But when they come back to > > meet it cannot be that both clocks were going slower. It is then claimed that the one that was on > > the spaceship will be the one that aged for some reason. https://en.wikipedia.org/wiki/Twin_paradox states: > > In the description above you have laid bare a lot of the misconceptions > about relativity that this puzzle was explicitly designed to illuminate. > > Among these misconceptions are: > - That the experiences of the two twins are symmetric > - That both twins will see the other's clock as being behind throughout > the whole trip > - That this puzzle is an example of inertial motion throughout > - That time dilation is all about clocks running slower and nothing else > (missing completely the point about synchronization being frame-dependent) > > Do you think those misconceptions are also in https://en.wikipedia.org/wiki/Twin_paradox If not, what did I write that made you think I was describing the situation any differently than the wiki write up? In the part you snipped I referenced the acceleration for example, so how could you think I was suggesting it was an example of inertial motion throughout, or symmetric (given the acceleration)? I didn't mention seeing each others clocks on the return journey either. I notice you didn't address any of the questions either. > -- > Odd Bodkin -- maker of fine toys, tools, tables
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| From | Odd Bodkin <bodkinodd@gmail.com> |
|---|---|
| Date | 2017-03-03 10:32 -0600 |
| Message-ID | <o9c5qc$1leu$1@gioia.aioe.org> |
| In reply to | #411559 |
On 3/3/2017 10:12 AM, someone wrote: > On Friday, March 3, 2017 at 3:09:25 PM UTC, Odd Bodkin wrote: >> On 3/3/2017 9:04 AM, someone wrote: >>> The twin paradox is as I understand it that there are twins, and one goes off in a spaceship, and as >>> it does from its perspective the other twins clock is going slower, but from the twin on Earths >>> perspective the twin going off in a spaceships clock is going slower. But when they come back to >>> meet it cannot be that both clocks were going slower. It is then claimed that the one that was on >>> the spaceship will be the one that aged for some reason. https://en.wikipedia.org/wiki/Twin_paradox states: >> >> In the description above you have laid bare a lot of the misconceptions >> about relativity that this puzzle was explicitly designed to illuminate. >> >> Among these misconceptions are: >> - That the experiences of the two twins are symmetric >> - That both twins will see the other's clock as being behind throughout >> the whole trip >> - That this puzzle is an example of inertial motion throughout >> - That time dilation is all about clocks running slower and nothing else >> (missing completely the point about synchronization being frame-dependent) >> >> > > Do you think those misconceptions are also in https://en.wikipedia.org/wiki/Twin_paradox > > If not, what did I write that made you think I was describing the situation any differently > than the wiki write up? In the part you snipped I referenced the acceleration for example, > so how could you think I was suggesting it was an example of inertial motion throughout, or > symmetric (given the acceleration)? > > I didn't mention seeing each others clocks on the return journey either. > > I notice you didn't address any of the questions either. The intent of my post was not to explain the twin paradox to you. There are plenty of really good expositions, especially in books, that do a fantastic job of doing that. The wiki article is not that great by the way, for exactly the same reason that learning zoology is not best done by looking up encyclopedia articles about different animals. It's better understood in the context of an explanation of special relativity as a whole. I recommend Taylor and Wheeler's book called Spacetime Physics. The purpose of my post was to simply say that the list of questions that you raise are exactly the questions that beginners to the subject ask, because they have certain misconceptions about what special relativity has to say about this situation. And so the twin puzzle is a useful teaching tool to correct those misconceptions. > > >> -- >> Odd Bodkin -- maker of fine toys, tools, tables > -- Odd Bodkin -- maker of fine toys, tools, tables
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| From | Jonathan Doolin <good4usoul@gmail.com> |
|---|---|
| Date | 2017-03-04 07:08 -0800 |
| Message-ID | <d336f957-572b-420d-9557-064dc80c806c@googlegroups.com> |
| In reply to | #411561 |
On Friday, March 3, 2017 at 10:32:15 AM UTC-6, Odd Bodkin wrote: > On 3/3/2017 10:12 AM, someone wrote: > > On Friday, March 3, 2017 at 3:09:25 PM UTC, Odd Bodkin wrote: > >> On 3/3/2017 9:04 AM, someone wrote: > >>> The twin paradox is as I understand it that there are twins, and one goes off in a spaceship, and as > >>> it does from its perspective the other twins clock is going slower, but from the twin on Earths > >>> perspective the twin going off in a spaceships clock is going slower. But when they come back to > >>> meet it cannot be that both clocks were going slower. It is then claimed that the one that was on > >>> the spaceship will be the one that aged for some reason. https://en.wikipedia.org/wiki/Twin_paradox states: > >> > >> In the description above you have laid bare a lot of the misconceptions > >> about relativity that this puzzle was explicitly designed to illuminate. > >> > >> Among these misconceptions are: > >> - That the experiences of the two twins are symmetric > >> - That both twins will see the other's clock as being behind throughout > >> the whole trip > >> - That this puzzle is an example of inertial motion throughout > >> - That time dilation is all about clocks running slower and nothing else > >> (missing completely the point about synchronization being frame-dependent) > >> > >> > > > > Do you think those misconceptions are also in https://en.wikipedia.org/wiki/Twin_paradox > > > > If not, what did I write that made you think I was describing the situation any differently > > than the wiki write up? In the part you snipped I referenced the acceleration for example, > > so how could you think I was suggesting it was an example of inertial motion throughout, or > > symmetric (given the acceleration)? > > > > I didn't mention seeing each others clocks on the return journey either. > > > > I notice you didn't address any of the questions either. > > The intent of my post was not to explain the twin paradox to you. There > are plenty of really good expositions, especially in books, that do a > fantastic job of doing that. The wiki article is not that great by the > way, for exactly the same reason that learning zoology is not best done > by looking up encyclopedia articles about different animals. It's better > understood in the context of an explanation of special relativity as a > whole. I recommend Taylor and Wheeler's book called Spacetime Physics. > > The purpose of my post was to simply say that the list of questions that > you raise are exactly the questions that beginners to the subject ask, > because they have certain misconceptions about what special relativity > has to say about this situation. And so the twin puzzle is a useful > teaching tool to correct those misconceptions. > > > > > > >> -- > >> Odd Bodkin -- maker of fine toys, tools, tables > > > > > -- > Odd Bodkin -- maker of fine toys, tools, tables If you go back to the talk pages in archive 14 you'll see some animations I made around that time. There is apparently, according to Dirk Van de Moortel, NO LITERATURE in peer-reviewed journals that actually shows the Lorentz Transformations actually done so that the spacetime diagram is shown in the three frames. Therefore any animation or discussion of what the two-dimensional spacetime diagram would look like from the perspective of the traveling twin during any moment of their travels is forbidden to be discussed in the article. Without that option to actually show the spacetime diagram in the rest frame of the outbound twin, the inbound twin, and the stay-at-home twin, the explanations tend to really give the impression that the traveling twin has no other data about what happened except, that their clock reads a smaller change than the stay-at-home twin. But this would of course not be the most notable thing that occurred during the twin's journey. For the twin, surely, the thing that would blow his mind during the journey would be the fact that during his turnaround, the image of the earth (indeed, for all intents and purposes, the earth itself) jumps back an enormous distance.
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| From | rotchm <rotchm@gmail.com> |
|---|---|
| Date | 2017-03-04 07:47 -0800 |
| Message-ID | <f4bce279-312f-403e-9d81-cf94aac4a0c5@googlegroups.com> |
| In reply to | #411676 |
On Saturday, March 4, 2017 at 10:08:41 AM UTC-5, Jonathan Doolin wrote: > For the twin, surely, the thing that would blow his mind during the > journey would be the fact that during his turnaround, Yes, for an instantaneous turnaround, that would blow his mind; it would tear him apart. Such instantaneous turnarounds are forbidden in SR & physics. To impose it is imposing a contradictory axiom into the model. But, if you propose a smoother turnaround, then all works out & computable. Or, use the three twin scenario; there, all works out and the analysis can be found in zillions of texts.
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| From | "David (Lord Kronos Prime) Fuller" <fuller.david@hotmail.com> |
|---|---|
| Date | 2017-03-04 09:15 -0800 |
| Message-ID | <e62ff00a-d404-43fe-8fec-c1e2e5ed84ce@googlegroups.com> |
| In reply to | #411680 |
Twin paradox solution Take the exact temperature of both twins at the initiation Kx & Ky After the accelerated journeys, the twin with the most Relativistic Mass will have a Higher temperature relative to its twin The clocks will be the same
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| From | Jonathan Doolin <good4usoul@gmail.com> |
|---|---|
| Date | 2017-03-04 10:23 -0800 |
| Message-ID | <024d1bbf-2e15-4dff-8c37-05653b68ef83@googlegroups.com> |
| In reply to | #411680 |
On Saturday, March 4, 2017 at 9:47:45 AM UTC-6, rotchm wrote: > On Saturday, March 4, 2017 at 10:08:41 AM UTC-5, Jonathan Doolin wrote: > > > For the twin, surely, the thing that would blow his mind during the > > journey would be the fact that during his turnaround, > > Yes, for an instantaneous turnaround, that would blow his mind; it would tear him apart. Such instantaneous turnarounds are forbidden in SR & physics. To impose it is imposing a contradictory axiom into the model. > But, if you propose a smoother turnaround, then all works out & computable. It's just a matter of scale. If you draw a space-time diagram which is 100s of light years across and hundreds of light years in time, then an impulse of 1 g acceleration for the period of a year would appear essentially instantaneous. > Or, use the three twin scenario; there, all works out and the analysis can be found in zillions of texts. Here's the diagram that WWoods made: https://upload.wikimedia.org/wikipedia/en/archive/d/dd/20100816203320%21Twin_5.png To my knowledge, that diagram doesn't appear in any of the zillions of texts. Otherwise it would be permissible to include it in the text of the wikipedia article on the twin paradox.
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| From | Sylvia Else <sylvia@not.at.this.address> |
|---|---|
| Date | 2017-03-05 11:42 +1100 |
| Message-ID | <ei1574Fdhs0U1@mid.individual.net> |
| In reply to | #411676 |
On 5/03/2017 2:08 AM, Jonathan Doolin wrote: > On Friday, March 3, 2017 at 10:32:15 AM UTC-6, Odd Bodkin wrote: >> On 3/3/2017 10:12 AM, someone wrote: >>> On Friday, March 3, 2017 at 3:09:25 PM UTC, Odd Bodkin wrote: >>>> On 3/3/2017 9:04 AM, someone wrote: >>>>> The twin paradox is as I understand it that there are twins, >>>>> and one goes off in a spaceship, and as it does from its >>>>> perspective the other twins clock is going slower, but from >>>>> the twin on Earths perspective the twin going off in a >>>>> spaceships clock is going slower. But when they come back to >>>>> meet it cannot be that both clocks were going slower. It is >>>>> then claimed that the one that was on the spaceship will be >>>>> the one that aged for some reason. >>>>> https://en.wikipedia.org/wiki/Twin_paradox states: >>>> >>>> In the description above you have laid bare a lot of the >>>> misconceptions about relativity that this puzzle was explicitly >>>> designed to illuminate. >>>> >>>> Among these misconceptions are: - That the experiences of the >>>> two twins are symmetric - That both twins will see the other's >>>> clock as being behind throughout the whole trip - That this >>>> puzzle is an example of inertial motion throughout - That time >>>> dilation is all about clocks running slower and nothing else >>>> (missing completely the point about synchronization being >>>> frame-dependent) >>>> >>>> >>> >>> Do you think those misconceptions are also in >>> https://en.wikipedia.org/wiki/Twin_paradox >>> >>> If not, what did I write that made you think I was describing the >>> situation any differently than the wiki write up? In the part you >>> snipped I referenced the acceleration for example, so how could >>> you think I was suggesting it was an example of inertial motion >>> throughout, or symmetric (given the acceleration)? >>> >>> I didn't mention seeing each others clocks on the return journey >>> either. >>> >>> I notice you didn't address any of the questions either. >> >> The intent of my post was not to explain the twin paradox to you. >> There are plenty of really good expositions, especially in books, >> that do a fantastic job of doing that. The wiki article is not that >> great by the way, for exactly the same reason that learning zoology >> is not best done by looking up encyclopedia articles about >> different animals. It's better understood in the context of an >> explanation of special relativity as a whole. I recommend Taylor >> and Wheeler's book called Spacetime Physics. >> >> The purpose of my post was to simply say that the list of questions >> that you raise are exactly the questions that beginners to the >> subject ask, because they have certain misconceptions about what >> special relativity has to say about this situation. And so the twin >> puzzle is a useful teaching tool to correct those misconceptions. >> >>> >>> >>>> -- Odd Bodkin -- maker of fine toys, tools, tables >>> >> >> >> -- Odd Bodkin -- maker of fine toys, tools, tables > > If you go back to the talk pages in archive 14 you'll see some > animations I made around that time. > > There is apparently, according to Dirk Van de Moortel, NO LITERATURE > in peer-reviewed journals that actually shows the Lorentz > Transformations actually done so that the spacetime diagram is shown > in the three frames. > > Therefore any animation or discussion of what the two-dimensional > spacetime diagram would look like from the perspective of the > traveling twin during any moment of their travels is forbidden to be > discussed in the article. > > > Without that option to actually show the spacetime diagram in the > rest frame of the outbound twin, the inbound twin, and the > stay-at-home twin, the explanations tend to really give the > impression that the traveling twin has no other data about what > happened except, that their clock reads a smaller change than the > stay-at-home twin. > > But this would of course not be the most notable thing that occurred > during the twin's journey. For the twin, surely, the thing that > would blow his mind during the journey would be the fact that during > his turnaround, the image of the earth (indeed, for all intents and > purposes, the earth itself) jumps back an enormous distance. > The image of the Earth would do nothing unusual other than changing from being somewhat red to somewhat blue. In particular, it would not jump. However, the observer's changed velocity relative to the Earth would mean that the *calculated* position of the Earth in the observer's frame would abruptly change, as would the calculated time on Earth. Sylvia.
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| From | Jonathan Doolin <good4usoul@gmail.com> |
|---|---|
| Date | 2017-03-05 08:55 -0800 |
| Message-ID | <f77d47bf-34b4-40d9-be1b-e2cd2f8a483b@googlegroups.com> |
| In reply to | #411734 |
On Saturday, March 4, 2017 at 6:42:15 PM UTC-6, Sylvia Else wrote: > On 5/03/2017 2:08 AM, Jonathan Doolin wrote: > > On Friday, March 3, 2017 at 10:32:15 AM UTC-6, Odd Bodkin wrote: > >> On 3/3/2017 10:12 AM, someone wrote: > >>> On Friday, March 3, 2017 at 3:09:25 PM UTC, Odd Bodkin wrote: > >>>> On 3/3/2017 9:04 AM, someone wrote: > >>>>> The twin paradox is as I understand it that there are twins, > >>>>> and one goes off in a spaceship, and as it does from its > >>>>> perspective the other twins clock is going slower, but from > >>>>> the twin on Earths perspective the twin going off in a > >>>>> spaceships clock is going slower. But when they come back to > >>>>> meet it cannot be that both clocks were going slower. It is > >>>>> then claimed that the one that was on the spaceship will be > >>>>> the one that aged for some reason. > >>>>> https://en.wikipedia.org/wiki/Twin_paradox states: > >>>> > >>>> In the description above you have laid bare a lot of the > >>>> misconceptions about relativity that this puzzle was explicitly > >>>> designed to illuminate. > >>>> > >>>> Among these misconceptions are: - That the experiences of the > >>>> two twins are symmetric - That both twins will see the other's > >>>> clock as being behind throughout the whole trip - That this > >>>> puzzle is an example of inertial motion throughout - That time > >>>> dilation is all about clocks running slower and nothing else > >>>> (missing completely the point about synchronization being > >>>> frame-dependent) > >>>> > >>>> > >>> > >>> Do you think those misconceptions are also in > >>> https://en.wikipedia.org/wiki/Twin_paradox > >>> > >>> If not, what did I write that made you think I was describing the > >>> situation any differently than the wiki write up? In the part you > >>> snipped I referenced the acceleration for example, so how could > >>> you think I was suggesting it was an example of inertial motion > >>> throughout, or symmetric (given the acceleration)? > >>> > >>> I didn't mention seeing each others clocks on the return journey > >>> either. > >>> > >>> I notice you didn't address any of the questions either. > >> > >> The intent of my post was not to explain the twin paradox to you. > >> There are plenty of really good expositions, especially in books, > >> that do a fantastic job of doing that. The wiki article is not that > >> great by the way, for exactly the same reason that learning zoology > >> is not best done by looking up encyclopedia articles about > >> different animals. It's better understood in the context of an > >> explanation of special relativity as a whole. I recommend Taylor > >> and Wheeler's book called Spacetime Physics. > >> > >> The purpose of my post was to simply say that the list of questions > >> that you raise are exactly the questions that beginners to the > >> subject ask, because they have certain misconceptions about what > >> special relativity has to say about this situation. And so the twin > >> puzzle is a useful teaching tool to correct those misconceptions. > >> > >>> > >>> > >>>> -- Odd Bodkin -- maker of fine toys, tools, tables > >>> > >> > >> > >> -- Odd Bodkin -- maker of fine toys, tools, tables > > > > If you go back to the talk pages in archive 14 you'll see some > > animations I made around that time. > > > > There is apparently, according to Dirk Van de Moortel, NO LITERATURE > > in peer-reviewed journals that actually shows the Lorentz > > Transformations actually done so that the spacetime diagram is shown > > in the three frames. > > > > Therefore any animation or discussion of what the two-dimensional > > spacetime diagram would look like from the perspective of the > > traveling twin during any moment of their travels is forbidden to be > > discussed in the article. > > > > > > Without that option to actually show the spacetime diagram in the > > rest frame of the outbound twin, the inbound twin, and the > > stay-at-home twin, the explanations tend to really give the > > impression that the traveling twin has no other data about what > > happened except, that their clock reads a smaller change than the > > stay-at-home twin. > > > > But this would of course not be the most notable thing that occurred > > during the twin's journey. For the twin, surely, the thing that > > would blow his mind during the journey would be the fact that during > > his turnaround, the image of the earth (indeed, for all intents and > > purposes, the earth itself) jumps back an enormous distance. > > > > The image of the Earth would do nothing unusual other than changing from > being somewhat red to somewhat blue. In particular, it would not jump. > > However, the observer's changed velocity relative to the Earth would > mean that the *calculated* position of the Earth in the observer's frame > would abruptly change, as would the calculated time on Earth. > > Sylvia. The image of an object in the view of the traveling twin has coordinates wherever its path intersects the past-light-cone of the observer. Watch the motion of events X, Y, F, and G in this animation https://en.wikipedia.org/wiki/Talk:Twin_paradox/Archive_14#/media/File:Lorentz_Transformations_of_Twin_Paradox_Minkowski_Diagram.gif You will see that event X recedes from the traveling twin when he accelerates to the right, and event F recedes from the origin when he accelerates to the left. So, the image does indeed essentially jump away from the observer when the observer accelerates toward it. You can actually see that phenomenon in this video, https://www.youtube.com/watch?v=TCz7oIzcpBE&feature=youtu.be&t=22m When he backs up, the distance to objects in front of him contracts. When he accelerates forwards, the distance to objects in front of him expands.
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| From | wugi <brol@brol.be> |
|---|---|
| Date | 2017-03-14 22:31 +0100 |
| Message-ID | <oa9nk1$d8j$1@gioia.aioe.org> |
| In reply to | #411734 |
Op 5/03/2017 om 1:42 schreef Sylvia Else:
> On 5/03/2017 2:08 AM, Jonathan Doolin wrote:
>> If you go back to the talk pages in archive 14 you'll see some
>> animations I made around that time.
>>
>> There is apparently, according to Dirk Van de Moortel, NO LITERATURE
>> in peer-reviewed journals that actually shows the Lorentz
>> Transformations actually done so that the spacetime diagram is shown
>> in the three frames.
I've always found it surprising anyway, what little graphical effort is
put in "officialish" publications ...
>> Therefore any animation or discussion of what the two-dimensional
>> spacetime diagram would look like from the perspective of the
>> traveling twin during any moment of their travels is forbidden to be
>> discussed in the article.
... that's why I've tried to do so in mine*, with the little basic tools
I had.
The different standpoints of home and travelling twins are one important
aspect; the difference between calculation results ("pure" Lorentz) and
actually seeing things (as light reaches the observer from different
events) another. And the graphical possibilities to visualize all this,
of course.
* http://home.scarlet.be/~pin12499/paratwin.htm
>> Without that option to actually show the spacetime diagram in the
>> rest frame of the outbound twin, the inbound twin, and the
>> stay-at-home twin, the explanations tend to really give the
>> impression that the traveling twin has no other data about what
>> happened except, that their clock reads a smaller change than the
>> stay-at-home twin.
And a mistaken impression it is ;-)
>> But this would of course not be the most notable thing that occurred
>> during the twin's journey. For the twin, surely, the thing that
>> would blow his mind during the journey would be the fact that during
>> his turnaround, the image of the earth (indeed, for all intents and
>> purposes, the earth itself) jumps back an enormous distance.
That's precisely a result that struck me as odd and has left me half
perplex ever since. So I mention it specially, look for
<<
after his instant maneuver, the hometwin appears to have got at a
different, greater distance (now in the homebound system, and
corresponding there to an "earlier" event) (*)
[...]
(*) This came as a surprise even to me. Imagine [...]
>>
under heading "Relasee, TP-wise".
> The image of the Earth would do nothing unusual other than changing from
> being somewhat red to somewhat blue. In particular, it would not jump.
>
> However, the observer's changed velocity relative to the Earth would
> mean that the *calculated* position of the Earth in the observer's frame
> would abruptly change, as would the calculated time on Earth.
>
> Sylvia.
Though the calculational observation would result in some change in
distance during the turnaround:
http://home.scarlet.be/~pin12499/MySRT/RelatyTravtwin2.PNG
(distance changes from DB to EB, even passing through a "rest distance"
value, but EB returning to same value as DB in the symmetrical case)
it is nothing like the big jump occurring during the actual "image" or
"seeing" observation:
http://home.scarlet.be/~pin12499/MySRT/TravtwinSee%20pt-of-vw.PNG
(Seeing observation of home-twin according to travelling twin, ie, with
his reference axes, outbound and inbound axes collapsed in a single system.
Left: as spacetime events.
Right: as instant perception at every moment of traveller's time).
Rv- : home twin, or Earth, "image" just before return event;
Rv+ : home twin, or Earth, "image" just after return event:
see the jump!
--
guido wugi
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| From | Jonathan Doolin <good4usoul@gmail.com> |
|---|---|
| Date | 2017-03-15 03:22 -0700 |
| Message-ID | <1af8b7c7-fe71-4bcd-810d-2967eb34cf05@googlegroups.com> |
| In reply to | #412846 |
On Tuesday, March 14, 2017 at 4:33:57 PM UTC-5, wugi wrote:
> Op 5/03/2017 om 1:42 schreef Sylvia Else:
> > On 5/03/2017 2:08 AM, Jonathan Doolin wrote:
>
> >> If you go back to the talk pages in archive 14 you'll see some
> >> animations I made around that time.
> >>
> >> There is apparently, according to Dirk Van de Moortel, NO LITERATURE
> >> in peer-reviewed journals that actually shows the Lorentz
> >> Transformations actually done so that the spacetime diagram is shown
> >> in the three frames.
>
> I've always found it surprising anyway, what little graphical effort is
> put in "officialish" publications ...
>
> >> Therefore any animation or discussion of what the two-dimensional
> >> spacetime diagram would look like from the perspective of the
> >> traveling twin during any moment of their travels is forbidden to be
> >> discussed in the article.
>
> ... that's why I've tried to do so in mine*, with the little basic tools
> I had.
> The different standpoints of home and travelling twins are one important
> aspect; the difference between calculation results ("pure" Lorentz) and
> actually seeing things (as light reaches the observer from different
> events) another. And the graphical possibilities to visualize all this,
> of course.
>
> * http://home.scarlet.be/~pin12499/paratwin.htm
>
> >> Without that option to actually show the spacetime diagram in the
> >> rest frame of the outbound twin, the inbound twin, and the
> >> stay-at-home twin, the explanations tend to really give the
> >> impression that the traveling twin has no other data about what
> >> happened except, that their clock reads a smaller change than the
> >> stay-at-home twin.
>
> And a mistaken impression it is ;-)
>
> >> But this would of course not be the most notable thing that occurred
> >> during the twin's journey. For the twin, surely, the thing that
> >> would blow his mind during the journey would be the fact that during
> >> his turnaround, the image of the earth (indeed, for all intents and
> >> purposes, the earth itself) jumps back an enormous distance.
>
> That's precisely a result that struck me as odd and has left me half
> perplex ever since. So I mention it specially, look for
> <<
> after his instant maneuver, the hometwin appears to have got at a
> different, greater distance (now in the homebound system, and
> corresponding there to an "earlier" event) (*)
> [...]
> (*) This came as a surprise even to me. Imagine [...]
> >>
> under heading "Relasee, TP-wise".
>
Well, it is no wonder a surprise, though, don't you think? Consideration of the distance to events and images in the frame of reference of the outbound twin, and the inbound twin, largely seems to be ignored by the mainstream. While there is a bit of interest in where events are "now" by Paul Anderson and Mike Fontenot, they get somewhat into the mainstream, because 'where things are now' demonstrates Lorentz Contraction.
But asking "where was it when it produced the image" doesn't get published. So even when MIT created their very nice demonstration "A Slower Speed of Light" though it shows very clearly, when you're running around the environment at 99% of the speed of light, that the images of objects definitely do appear to recede when you accelerate toward them, they do not offer any sort of explanation or mention of this phenomenon in their information about the program.
I gather, that's because there's simply no papers on the topic.
> > The image of the Earth would do nothing unusual other than changing from
> > being somewhat red to somewhat blue. In particular, it would not jump.
> >
> > However, the observer's changed velocity relative to the Earth would
> > mean that the *calculated* position of the Earth in the observer's frame
> > would abruptly change, as would the calculated time on Earth.
> >
> > Sylvia.
>
> Though the calculational observation would result in some change in
> distance during the turnaround:
> http://home.scarlet.be/~pin12499/MySRT/RelatyTravtwin2.PNG
> (distance changes from DB to EB, even passing through a "rest distance"
> value, but EB returning to same value as DB in the symmetrical case)
>
> it is nothing like the big jump occurring during the actual "image" or
> "seeing" observation:
> http://home.scarlet.be/~pin12499/MySRT/TravtwinSee%20pt-of-vw.PNG
> (Seeing observation of home-twin according to travelling twin, ie, with
> his reference axes, outbound and inbound axes collapsed in a single system.
I have independent confirmation of the left-hand half of this diagram.
Please watch this:
https://www.youtube.com/watch?v=j_csFp-QZGg&lc=z13ffv3xnmjxifj5304cjprgur3wwzez42c
At about 8:30 in the video I construct a "Noninertial Rest Frame" But instead of constructing it by erasing events above and below the line of simultaneity, it is constructed by erasing events above and below the past light cone of the traveling observer.
This preserves all of the events in the space, so that each event is represented only once.
> Left: as spacetime events.
> Right: as instant perception at every moment of traveller's time).
> Rv- : home twin, or Earth, "image" just before return event;
> Rv+ : home twin, or Earth, "image" just after return event:
> see the jump!
>
> --
> guido wugi
Yes. Your Rv- and Rv+ is represented in this animation as event F.
https://en.wikipedia.org/wiki/Talk:Twin_paradox/Archive_14#/media/File:Lorentz_Transformations_of_Twin_Paradox_Minkowski_Diagram.gif
Thank you for responding.
It is really nice to have a response from someone who has has done some of the same modeling.
Jonathan Doolin
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| From | wugi <brol@brol.be> |
|---|---|
| Date | 2017-03-17 18:39 +0100 |
| Message-ID | <oah6tb$12pa$1@gioia.aioe.org> |
| In reply to | #412905 |
Op 15/03/2017 om 11:22 schreef Jonathan Doolin: > On Tuesday, March 14, 2017 at 4:33:57 PM UTC-5, wugi wrote: >> Op 5/03/2017 om 1:42 schreef Sylvia Else: >>> On 5/03/2017 2:08 AM, Jonathan Doolin wrote: >> ... >>>> But this would of course not be the most notable thing that occurred >>>> during the twin's journey. For the twin, surely, the thing that >>>> would blow his mind during the journey would be the fact that during >>>> his turnaround, the image of the earth (indeed, for all intents and >>>> purposes, the earth itself) jumps back an enormous distance. >> >> That's precisely a result that struck me as odd and has left me half >> perplex ever since. So I mention it specially, look for >> << >> after his instant maneuver, the hometwin appears to have got at a >> different, greater distance (now in the homebound system, and >> corresponding there to an "earlier" event) (*) >> [...] >> (*) This came as a surprise even to me. Imagine [...] >> >> >> under heading "Relasee, TP-wise". >> > > Well, it is no wonder a surprise, though, don't you think? Consideration Most other aspects of TP I could grasp "intuitively", but this one had me wince a bit ;-) > of the distance to events and images in the frame of reference of the > outbound twin, and the inbound twin, largely seems to be ignored by the > mainstream. While there is a bit of interest in where events are "now" > by Paul Anderson and Mike Fontenot, they get somewhat into the > mainstream, because 'where things are now' demonstrates Lorentz Contraction. I see now that the wiki article has at least got some paragraphs on the "seeing" aspect: "What it looks like", "The distinction between what they see and what they calculate", ... But the graphics appears wanting more and better, doesn't it? (My own aspirations would be: distinguish clearly the Lorentz/measuring and the -what I call- Einstein/seeing processes, developping both twins' standpoints. And graphics, graphics...) Unfortunately the mainstream, as you said, is very opaque for outside ideas. I see a big defensive wall there :-( /// (-; Admittedly it's a hazardous job to seperate creative input from jokers and trolls, witness usenet groups... > But asking "where was it when it produced the image" doesn't get > published. So even when MIT created their very nice demonstration "A > Slower Speed of Light" though it shows very clearly, when you're running > around the environment at 99% of the speed of light, that the images of > objects definitely do appear to recede when you accelerate toward them, > they do not offer any sort of explanation or mention of this phenomenon > in their information about the program. I'm not sure what you meant here. I could only explain a case of "seeing an object recede" "when you accelerate toward them" as an event where 1. you have started approaching the object, but 2. you still are seeing (retarded light signals from) a previous recession phase. > I gather, that's because there's simply no papers on the topic. >>> The image of the Earth would do nothing unusual other than changing from >>> being somewhat red to somewhat blue. In particular, it would not jump. >>> >>> However, the observer's changed velocity relative to the Earth would >>> mean that the *calculated* position of the Earth in the observer's frame >>> would abruptly change, as would the calculated time on Earth. >>> >>> Sylvia. >> >> Though the calculational observation would result in some change in >> distance during the turnaround: >> http://home.scarlet.be/~pin12499/MySRT/RelatyTravtwin2.PNG >> (distance changes from DB to EB, even passing through a "rest distance" >> value, but EB returning to same value as DB in the symmetrical case) >> >> it is nothing like the big jump occurring during the actual "image" or >> "seeing" observation: >> http://home.scarlet.be/~pin12499/MySRT/TravtwinSee%20pt-of-vw.PNG >> (Seeing observation of home-twin according to travelling twin, ie, with >> his reference axes, outbound and inbound axes collapsed in a single system. > > > I have independent confirmation of the left-hand half of this diagram. > > Please watch this: > https://www.youtube.com/watch?v=j_csFp-QZGg&lc=z13ffv3xnmjxifj5304cjprgur3wwzez42c > > At about 8:30 in the video I construct a "Noninertial Rest Frame" > But > instead of constructing it by erasing events above and below the line of > simultaneity, it is constructed by erasing events above and below the > past light cone of the traveling observer. > > This preserves all of the events in the space, so that each event is > represented only once. Yes, the right figure at around 10: corresponds to my "TravTwinSee" diagram above. The left figure would correspond to a "TravTwinLorentz" diagram that I haven't done yet myself (showing the "simultaneity lengths" during turnaround sweeping from contracted through rest back to contracted values). >> Left: as spacetime events. >> Right: as instant perception at every moment of traveller's time). >> Rv- : home twin, or Earth, "image" just before return event; >> Rv+ : home twin, or Earth, "image" just after return event: >> see the jump! >> >> -- guido wugi > > Yes. Your Rv- and Rv+ is represented in this animation as event F. > > https://en.wikipedia.org/wiki/Talk:Twin_paradox/Archive_14#/media/File:Lorentz_Transformations_of_Twin_Paradox_Minkowski_Diagram.gif > Thank you for responding. > It is really nice to have a response from someone who has has done some of the same modeling. Same here. -- guido wugi
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| From | Jonathan Doolin <good4usoul@gmail.com> |
|---|---|
| Date | 2017-03-17 13:56 -0700 |
| Message-ID | <b6bf47ab-0d8c-4c51-9241-4362dedc805e@googlegroups.com> |
| In reply to | #413135 |
On Friday, March 17, 2017 at 12:37:52 PM UTC-5, wugi wrote: > Op 15/03/2017 om 11:22 schreef Jonathan Doolin: > > On Tuesday, March 14, 2017 at 4:33:57 PM UTC-5, wugi wrote: > >> Op 5/03/2017 om 1:42 schreef Sylvia Else: > >>> On 5/03/2017 2:08 AM, Jonathan Doolin wrote: > >> > > ... > > >>>> But this would of course not be the most notable thing that occurred > >>>> during the twin's journey. For the twin, surely, the thing that > >>>> would blow his mind during the journey would be the fact that during > >>>> his turnaround, the image of the earth (indeed, for all intents and > >>>> purposes, the earth itself) jumps back an enormous distance. > >> > >> That's precisely a result that struck me as odd and has left me half > >> perplex ever since. So I mention it specially, look for > >> << > >> after his instant maneuver, the hometwin appears to have got at a > >> different, greater distance (now in the homebound system, and > >> corresponding there to an "earlier" event) (*) > >> [...] > >> (*) This came as a surprise even to me. Imagine [...] > >> >> > >> under heading "Relasee, TP-wise". > >> > > > > Well, it is no wonder a surprise, though, don't you think? Consideration > > Most other aspects of TP I could grasp "intuitively", but this one had > me wince a bit ;-) > > > of the distance to events and images in the frame of reference of the > > outbound twin, and the inbound twin, largely seems to be ignored by the > > mainstream. While there is a bit of interest in where events are "now" > > by Paul Anderson and Mike Fontenot, they get somewhat into the > > mainstream, because 'where things are now' demonstrates Lorentz Contraction. > > I see now that the wiki article has at least got some paragraphs on the > "seeing" aspect: "What it looks like", "The distinction between what > they see and what they calculate", ... But the graphics appears wanting > more and better, doesn't it? > (My own aspirations would be: distinguish clearly the Lorentz/measuring > and the -what I call- Einstein/seeing processes, developping both twins' > standpoints. And graphics, graphics...) > Unfortunately the mainstream, as you said, is very opaque for outside > ideas. I see a big defensive wall there :-( /// (-; > Admittedly it's a hazardous job to seperate creative input from jokers > and trolls, witness usenet groups... > > > But asking "where was it when it produced the image" doesn't get > > published. So even when MIT created their very nice demonstration "A > > Slower Speed of Light" though it shows very clearly, when you're running > > around the environment at 99% of the speed of light, that the images of > > objects definitely do appear to recede when you accelerate toward them, > > they do not offer any sort of explanation or mention of this phenomenon > > in their information about the program. > > I'm not sure what you meant here. I could only explain a case of "seeing > an object recede" "when you accelerate toward them" as an event where > 1. you have started approaching the object, but > 2. you still are seeing (retarded light signals from) a previous > recession phase. > If you have a reasonably good graphics card on your computer, you should download http://gamelab.mit.edu/games/a-slower-speed-of-light/ and see the phenomena that I am talking about once you eat 90 to 99 watermelons... okay, they don't call them watermelons, but they look like watermelons. > > I gather, that's because there's simply no papers on the topic. > > >>> The image of the Earth would do nothing unusual other than changing from > >>> being somewhat red to somewhat blue. In particular, it would not jump. > >>> > >>> However, the observer's changed velocity relative to the Earth would > >>> mean that the *calculated* position of the Earth in the observer's frame > >>> would abruptly change, as would the calculated time on Earth. > >>> > >>> Sylvia. > >> > >> Though the calculational observation would result in some change in > >> distance during the turnaround: > >> http://home.scarlet.be/~pin12499/MySRT/RelatyTravtwin2.PNG > >> (distance changes from DB to EB, even passing through a "rest distance" > >> value, but EB returning to same value as DB in the symmetrical case) > >> > >> it is nothing like the big jump occurring during the actual "image" or > >> "seeing" observation: > >> http://home.scarlet.be/~pin12499/MySRT/TravtwinSee%20pt-of-vw.PNG > >> (Seeing observation of home-twin according to travelling twin, ie, with > >> his reference axes, outbound and inbound axes collapsed in a single system. > > > > > > I have independent confirmation of the left-hand half of this diagram. > > > > Please watch this: > > > https://www.youtube.com/watch?v=j_csFp-QZGg&lc=z13ffv3xnmjxifj5304cjprgur3wwzez42c > > > > At about 8:30 in the video I construct a "Noninertial Rest Frame" > > But > > instead of constructing it by erasing events above and below the line of > > simultaneity, it is constructed by erasing events above and below the > > past light cone of the traveling observer. > > > > This preserves all of the events in the space, so that each event is > > represented only once. > > Yes, the right figure at around 10: corresponds to my "TravTwinSee" > diagram above. > The left figure would correspond to a "TravTwinLorentz" diagram that I > haven't done yet myself (showing the "simultaneity lengths" during > turnaround sweeping from contracted through rest back to contracted values). > Right. The little A-to-C path is a little pulse out to uncontracted length, and then back again. That path is modeled pretty nicely in Paul Anderson's demonstration, a few pages back. > >> Left: as spacetime events. > >> Right: as instant perception at every moment of traveller's time). > >> Rv- : home twin, or Earth, "image" just before return event; > >> Rv+ : home twin, or Earth, "image" just after return event: > >> see the jump! > >> > >> -- guido wugi > > > > Yes. Your Rv- and Rv+ is represented in this animation as event F. > > > > > https://en.wikipedia.org/wiki/Talk:Twin_paradox/Archive_14#/media/File:Lorentz_Transformations_of_Twin_Paradox_Minkowski_Diagram.gif > > > Thank you for responding. > > It is really nice to have a response from someone who has has done > some of the same modeling. > > Same here. > > -- > guido wugi I saw on your page, http://home.scarlet.be/~pin12499/paratwin.htm some discussion of the Penrose Terrell Rotation. It got me to update my website on that topic here: http://www.spoonfedrelativity.com/pages/PenroseTerrellRotation.php
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| From | wugi <brol@brol.be> |
|---|---|
| Date | 2017-03-17 22:54 +0100 |
| Message-ID | <oahlsf$1tpq$1@gioia.aioe.org> |
| In reply to | #413157 |
Op 17/03/2017 om 21:56 schreef Jonathan Doolin: > I saw on your page, http://home.scarlet.be/~pin12499/paratwin.htm some > discussion of the Penrose Terrell Rotation. It got me to update my Yes, the 'explanation' as I read and understood it is IMHO besides the issue as it would represent neither the Lorentz [parameters of a relativistic] object nor its "visual" materialisation. The former would be simply contracted squares (given initial "rest" squares); the latter would indeed be "bent squares", but not parallellograms, rather trapezia, and not upon the *contracted* length but upon the *SEEN* lengths, that is, dilated at approach, extra contracted at regression, and a mix during passing by. See my "squad" example: http://home.scarlet.be/~pin12499/MySRT/Squad.gif Only at a far distance perpendicular to the movement (the farthest part of the 'vertical' through observer's position "o" in the picture) can a seemingly rotated "Penrose Terrell" parallellogram be seen, because there the seen length becomes (almost) the Lorentz contracted length. > website on that topic here: > http://www.spoonfedrelativity.com/pages/PenroseTerrellRotation.php May I ask what the update is? -- guido wugi
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| From | Jonathan Doolin <good4usoul@gmail.com> |
|---|---|
| Date | 2017-03-17 17:32 -0700 |
| Message-ID | <5cbf564a-4931-45c8-b3f6-47f3d347510e@googlegroups.com> |
| In reply to | #413167 |
On Friday, March 17, 2017 at 4:53:23 PM UTC-5, wugi wrote: > Op 17/03/2017 om 21:56 schreef Jonathan Doolin: > > > > I saw on your page, http://home.scarlet.be/~pin12499/paratwin.htm some > > discussion of the Penrose Terrell Rotation. It got me to update my > > Yes, the 'explanation' as I read and understood it is IMHO besides the > issue as it would represent neither the Lorentz [parameters of a > relativistic] object nor its "visual" materialisation. The former would > be simply contracted squares (given initial "rest" squares); the latter > would indeed be "bent squares", but not parallellograms, rather > trapezia, and not upon the *contracted* length but upon the *SEEN* > lengths, that is, dilated at approach, extra contracted at regression, > and a mix during passing by. > > See my "squad" example: > http://home.scarlet.be/~pin12499/MySRT/Squad.gif > > Only at a far distance perpendicular to the movement (the farthest part > of the 'vertical' through observer's position "o" in the picture) can a > seemingly rotated "Penrose Terrell" parallellogram be seen, because > there the seen length becomes (almost) the Lorentz contracted length. > > > website on that topic here: > > http://www.spoonfedrelativity.com/pages/PenroseTerrellRotation.php > > May I ask what the update is? > > -- > guido wugi If you followed the original conversation in May, 2015, then it wasn't really updated from that. The update was that I put the animations on my website, so you could see them all together. Our general consensus from that conversation was that in fact you CAN see Lorentz contraction in the plane of your eye as the path of the object is perpendicular to your point-of-view. Three-dimensional spherical objects do retain their spherical appearance. But we all found Terrell's claim that "Lorentz Contraction is Invisible" to be a more than a little misleading.
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| From | wugi <brol@brol.be> |
|---|---|
| Date | 2017-03-18 18:16 +0100 |
| Message-ID | <oajpvc$1ddg$1@gioia.aioe.org> |
| In reply to | #413193 |
Op 18/03/2017 om 1:32 schreef Jonathan Doolin: > On Friday, March 17, 2017 at 4:53:23 PM UTC-5, wugi wrote: >> Op 17/03/2017 om 21:56 schreef Jonathan Doolin: >> >> >>> I saw on your page, http://home.scarlet.be/~pin12499/paratwin.htm some >>> discussion of the Penrose Terrell Rotation. It got me to update my >> >> Yes, the 'explanation' as I read and understood it is IMHO besides the >> issue as it would represent neither the Lorentz [parameters of a >> relativistic] object nor its "visual" materialisation. The former would >> be simply contracted squares (given initial "rest" squares); the latter >> would indeed be "bent squares", but not parallellograms, rather >> trapezia, and not upon the *contracted* length but upon the *SEEN* >> lengths, that is, dilated at approach, extra contracted at regression, >> and a mix during passing by. >> >> See my "squad" example: >> http://home.scarlet.be/~pin12499/MySRT/Squad.gif >> >> Only at a far distance perpendicular to the movement (the farthest part >> of the 'vertical' through observer's position "o" in the picture) can a >> seemingly rotated "Penrose Terrell" parallellogram be seen, because >> there the seen length becomes (almost) the Lorentz contracted length. >> >>> website on that topic here: >>> http://www.spoonfedrelativity.com/pages/PenroseTerrellRotation.php >> >> May I ask what the update is? >> >> -- >> guido wugi > > If you followed the original conversation in May, 2015, then it wasn't > really updated from that. The update was that I put the animations on my > website, so you could see them all together. You seemed to be confused about the dice positions. I don't see the problem of this rendering in a linear perspective (perhaps with minor 3D corrections) not unlike my "squad" picture up here: there too it can be verified that the observer can see the back sides of some not yet passing squares... And the passing edges/faces don't leave the straight lines or planes of the grid or, if they do, it's a matter of having the perspective straight or bent, not of their movement. As for how the dice would appear when just passing by perpendicularly (not treated indeed in the video): see below. > Our general consensus from that conversation was that in fact you > CAN > see Lorentz contraction in the plane of your eye as the path of the > object is perpendicular to your point-of-view. That's part of what I said above too (looking in a direction "*perpendicular* to the movement"...) but not complete: it has to be also "at a *far* distance"! At shorter distances you may see the object passing by (a back part approaching yet and a front part already receding) more or less Lorentz contracted (in one position even exactly so), but it WON'T be in correct proportions, as the approaching part has still the approach length dilation, and the receding part already the extra length contraction. See my picture 25 of the TAK chapter, showing a train coach passing by: http://home.scarlet.be/~pin12499/giffls/tak25.htm Description: The downmost image is the * Lorentz contracted coach. Then, going up: * coach seen at approach (length dilation) * coach seen passing by, with its centre at observer's position (composition symmetric but lengths not); * coach seen passing by, when total length equals Lorentz length (lengths symmetric but composition not) * coach seen receding (extra length contraction) Repeat: a 'good' Lorentz contracted coach is to be seen farther away along that direction, where the approach and recession length tend to the Lorentz value... > Three-dimensional spherical objects do retain their spherical > appearance. > > But we all found Terrell's claim that "Lorentz Contraction is > Invisible" to be a more than a little misleading. Yes, but only not right (ie, "Visible") in a particular direction and at sufficient distance... -- guido wugi
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| From | Jonathan Doolin <good4usoul@gmail.com> |
|---|---|
| Date | 2017-03-19 08:28 -0700 |
| Message-ID | <b7cca51c-3bde-435d-93c3-6f310ec532ac@googlegroups.com> |
| In reply to | #413256 |
On Saturday, March 18, 2017 at 12:15:29 PM UTC-5, wugi wrote: > Op 18/03/2017 om 1:32 schreef Jonathan Doolin: > > On Friday, March 17, 2017 at 4:53:23 PM UTC-5, wugi wrote: > >> Op 17/03/2017 om 21:56 schreef Jonathan Doolin: > >> > >> > >>> I saw on your page, http://home.scarlet.be/~pin12499/paratwin.htm some > >>> discussion of the Penrose Terrell Rotation. It got me to update my > >> > >> Yes, the 'explanation' as I read and understood it is IMHO besides the > >> issue as it would represent neither the Lorentz [parameters of a > >> relativistic] object nor its "visual" materialisation. The former would > >> be simply contracted squares (given initial "rest" squares); the latter > >> would indeed be "bent squares", but not parallellograms, rather > >> trapezia, and not upon the *contracted* length but upon the *SEEN* > >> lengths, that is, dilated at approach, extra contracted at regression, > >> and a mix during passing by. > >> > >> See my "squad" example: > >> http://home.scarlet.be/~pin12499/MySRT/Squad.gif > >> > >> Only at a far distance perpendicular to the movement (the farthest part > >> of the 'vertical' through observer's position "o" in the picture) can a > >> seemingly rotated "Penrose Terrell" parallellogram be seen, because > >> there the seen length becomes (almost) the Lorentz contracted length. > >> > >>> website on that topic here: > >>> http://www.spoonfedrelativity.com/pages/PenroseTerrellRotation.php > >> > >> May I ask what the update is? > >> > >> -- > >> guido wugi > > > > If you followed the original conversation in May, 2015, then it wasn't > > really updated from that. The update was that I put the animations on my > > website, so you could see them all together. > > You seemed to be confused about the dice positions. I don't see the Yes, I was confused about the dice positions at first. I cleared it up, somewhat here. https://www.physicsforums.com/threads/terrell-revisited-the-invisibility-of-the-lorentz-contraction.520875/page-6#post-5101005 > problem of this rendering in a linear perspective (perhaps with minor 3D > corrections) not unlike my "squad" picture up here: there too it can be > verified that the observer can see the back sides of some not yet > passing squares... And the passing edges/faces don't leave the straight > lines or planes of the grid or, if they do, it's a matter of having the > perspective straight or bent, not of their movement. > As for how the dice would appear when just passing by perpendicularly > (not treated indeed in the video): see below. > I should probably make another video, that clears that up... I guess I stopped making videos and started making animated gifs, then the gifs seemed so cool, I never got back to the videos. And yes... you do end up seeing the back face of the cube as it approaches. Because the light moving perpendicular to the back face of the cube is actually coming toward you, and going into your eyes. > > Our general consensus from that conversation was that in fact you > > CAN > > see Lorentz contraction in the plane of your eye as the path of the > > object is perpendicular to your point-of-view. > > That's part of what I said above too (looking in a direction > "*perpendicular* to the movement"...) but not complete: it has to be > also "at a *far* distance"! > And it has to be a far enough distance that the object occupies a small angle. And I think the small angle involved here is considerably smaller than the small-angle-approximation... See https://en.wikipedia.org/wiki/Small-angle_approximation it says: tan θ ≈ θ at about 0.176 radians (10°). sin θ ≈ θ at about 0.244 radians (14°). I think I once worked out what angle was necessary for Lorentz Contraction to be correct within 1% of observed size, but it was less than .176 radians. > At shorter distances you may see the object passing by (a back part > approaching yet and a front part already receding) more or less Lorentz > contracted (in one position even exactly so), but it WON'T be in correct > proportions, as the approaching part has still the approach length > dilation, and the receding part already the extra length contraction. > See my picture 25 of the TAK chapter, showing a train coach passing by: > http://home.scarlet.be/~pin12499/giffls/tak25.htm > > Description: > The downmost image is the > * Lorentz contracted coach. > Then, going up: > * coach seen at approach (length dilation) > * coach seen passing by, with its centre at observer's position > (composition symmetric but lengths not); Yes. I sent some emails to the MIT team that created "A Slower Speed of Light" and that is an issue that needs to be repaired in their demo. Their skinning algorithm should include effects such as are present in your image there in the third image, where the front of the train is a bit contracted, and the rear of the train is still extended. Of course, that would be a lot of work to fix. > * coach seen passing by, when total length equals Lorentz length > (lengths symmetric but composition not) > * coach seen receding (extra length contraction) > > Repeat: a 'good' Lorentz contracted coach is to be seen farther away > along that direction, where the approach and recession length tend to > the Lorentz value... > > > Three-dimensional spherical objects do retain their spherical > > appearance. > > > > But we all found Terrell's claim that "Lorentz Contraction is > > Invisible" to be a more than a little misleading. > > Yes, but only not right (ie, "Visible") in a particular direction and at > sufficient distance... > > -- > guido wugi I think, as Douglas Adams would have put it, Lorentz Contraction is "something almost, but not entirely unlike" invisible.
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| From | wugi <brol@brol.be> |
|---|---|
| Date | 2017-03-19 23:09 +0100 |
| Message-ID | <oamvfa$vob$1@gioia.aioe.org> |
| In reply to | #413353 |
Op 19/03/2017 om 16:28 schreef Jonathan Doolin: > On Saturday, March 18, 2017 at 12:15:29 PM UTC-5, wugi wrote: >> You seemed to be confused about the dice positions. I don't see the > > Yes, I was confused about the dice positions at first. > > I cleared it up, somewhat here. > > https://www.physicsforums.com/threads/terrell-revisited-the-invisibility-of-the-lorentz-contraction.520875/page-6#post-5101005 You could also play a bit with colors to suggest Doppler effects at approach and recession ;-) > I should probably make another video, that clears that up... I guess I > stopped making videos and started making animated gifs, then the gifs > seemed so cool, I never got back to the videos. I prefer the gifs too ;) May I know which software you're using for them? Cool graphics. Provided it's not more complicated than Basic :-o > And yes... you do end up seeing the back face of the cube as it > approaches. Because the light moving perpendicular to the back face of > the cube is actually coming toward you, and going into your eyes. >> Description: >> The downmost image is the >> * Lorentz contracted coach. >> Then, going up: >> * coach seen at approach (length dilation) >> * coach seen passing by, with its centre at observer's position >> (composition symmetric but lengths not); > > Yes. I sent some emails to the MIT team that created "A Slower Speed of > Light" and that is an issue that needs to be repaired in their demo. > Their skinning algorithm should include effects such as are present in > your image there in the third image, where the front of the train is a > bit contracted, and the rear of the train is still extended. Nowadays things have to be fun, also in science and education. In my days you could have left me breathless when watching a program like Horizon (but our national versions admittedly) or listening to an inspired teacher. Now it has to be Games and Fun apps. I'd have preferred to see MIT come up with breathtaking interactive explanatory demos of what's going on with relativistic phenomena, with good graphics but also with precise information, and without the "ludic" obsession. > Of course, that would be a lot of work to fix. > >> * coach seen passing by, when total length equals Lorentz length >> (lengths symmetric but composition not) That too is interesting meseems, in contrast with the former... >> * coach seen receding (extra length contraction) >> > I think, as Douglas Adams would have put it, Lorentz Contraction is > "something almost, but not entirely unlike" invisible. I think it is interesting and important to distinguish, evaluate and name the "apparent" (seen) lengths and velocities, and compare them with rest and Lorentz values, as I do in my pages. I haven't seen much of that elsewhere yet... -- guido wugi
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| From | Jonathan Doolin <good4usoul@gmail.com> |
|---|---|
| Date | 2017-03-20 08:14 -0700 |
| Message-ID | <318c9eb2-38f0-4733-8ce5-7d739fc214fc@googlegroups.com> |
| In reply to | #413382 |
On Sunday, March 19, 2017 at 5:07:42 PM UTC-5, wugi wrote: > Op 19/03/2017 om 16:28 schreef Jonathan Doolin: > > On Saturday, March 18, 2017 at 12:15:29 PM UTC-5, wugi wrote: > > >> You seemed to be confused about the dice positions. I don't see the > > > > Yes, I was confused about the dice positions at first. > > > > I cleared it up, somewhat here. > > > > https://www.physicsforums.com/threads/terrell-revisited-the-invisibility-of-the-lorentz-contraction.520875/page-6#post-5101005 > > You could also play a bit with colors to suggest Doppler effects at > approach and recession ;-) > > > I should probably make another video, that clears that up... I guess I > > stopped making videos and started making animated gifs, then the gifs > > seemed so cool, I never got back to the videos. > > I prefer the gifs too ;) > May I know which software you're using for them? Cool graphics. Provided > it's not more complicated than Basic :-o > Yes, this is Mathematica. The worst thing about it is that it is only offered on a subscription basis. The most vital thing that Mathematica did for me was solve an equation relating the world-line of a passing object and the past-light-cone of an observer. So I could focus on just figuring out equations for each worldline, and it would calculate the position where the event was observed in each frame of the animation. In most any other programming language, you would have to work through the algebra to solve for the intersection of the world-line and past-light-cone. > > And yes... you do end up seeing the back face of the cube as it > > approaches. Because the light moving perpendicular to the back face of > > the cube is actually coming toward you, and going into your eyes. > > > >> Description: > >> The downmost image is the > >> * Lorentz contracted coach. > >> Then, going up: > >> * coach seen at approach (length dilation) > >> * coach seen passing by, with its centre at observer's position > >> (composition symmetric but lengths not); > > > > Yes. I sent some emails to the MIT team that created "A Slower Speed of > > Light" and that is an issue that needs to be repaired in their demo. > > Their skinning algorithm should include effects such as are present in > > your image there in the third image, where the front of the train is a > > bit contracted, and the rear of the train is still extended. > > Nowadays things have to be fun, also in science and education. In my > days you could have left me breathless when watching a program like > Horizon (but our national versions admittedly) or listening to an > inspired teacher. Now it has to be Games and Fun apps. > I'd have preferred to see MIT come up with breathtaking interactive > explanatory demos of what's going on with relativistic phenomena, with > good graphics but also with precise information, and without the "ludic" > obsession. > If I'm not mistaken, the MIT team was using an open-source set of graphics objects that was put out by someone else. I've been thinking to have a look for it, someday, and find out whether I could use it. > > Of course, that would be a lot of work to fix. > > > >> * coach seen passing by, when total length equals Lorentz length > >> (lengths symmetric but composition not) > > That too is interesting meseems, in contrast with the former... > > >> * coach seen receding (extra length contraction) > >> > > > I think, as Douglas Adams would have put it, Lorentz Contraction is > > "something almost, but not entirely unlike" invisible. > > I think it is interesting and important to distinguish, evaluate and > name the "apparent" (seen) lengths and velocities, and compare them with > rest and Lorentz values, as I do in my pages. I haven't seen much of > that elsewhere yet... > > -- > guido wugi It's extremely rare indeed. The peer reviewed journals are all too intent on publishing papers that reject simple application of Lorentz Transformations. Examples: Penrose's paper to show that Lorentz Contraction was invisible for spheres Terrell's paper to show that Lorentz Contraction was invisible at a certain angle. Dolby and Gull's paper to show that one could develop a set of time isoclines that don't cross, while failing to acknowledge that the reference frame of an accelerating observer actually changes. ... and a vast array of articles that implicitly or explicitly claim that Special Relativity does not apply over cosmological distances.
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