Groups > sci.physics.relativity > #615483

Re: Twin paradox article in Wikipedia

From	Meredith Adamou <utto@mddaeaem.tt>
Newsgroups	sci.physics.relativity, sci.physics, sci.math
Subject	Re: Twin paradox article in Wikipedia
Date	2023-07-16 18:55 +0000
Organization	To protect and to server
Message-ID	<u91ef5$2fblq$1@paganini.bofh.team> (permalink)
References	(9 earlier) <835d82bf-dffa-4c5a-baa8-241351ded214n@googlegroups.com> <1qdyli5.11csf2egkegvzN%nospam@de-ster.demon.nl> <5f21ab34-121e-423e-95dd-75d972e3ef8bn@googlegroups.com> <1qdypyu.doyqa11jd20pwN%nospam@de-ster.demon.nl> <7pidnYwpmeIxZS75nZ2dnZfqlJxh4p2d@giganews.com>

Cross-posted to 3 groups.

Show all headers | View raw

Tom Roberts wrote:

> On 7/16/23 6:36 AM, J. J. Lodder wrote:
>> Spectrographs using gratings cannot 'measure' wavelengths at all. They
>> can at best compare wavelengths. (if you really insist)
> 
> Nonsense!
> First, any measurement using a unit is actually a comparison (of the
> measurement to the unit).
> Second, every analysis I have ever seen of a diffraction grating is
> based on the wavelength of the light, not its frequency. In particular,
> using c/f instead of wavelength is valid only in vacuum.
> Third, if what you claim were true, then a given laser and grating would
> show the same deflection angle when the grating is immersed in water or
> in air (the frequency of the light is the same, its wavelength isn't.).
> The angle changes corresponding to the wavelength, not the frequency.

absolutely, but there are nu units in wavelengths. So I guess is a 
comparison to a predefined chroma/color. Actually is even more complicate, 
as for instance, depending on intensity a "red" may have tons of nuances. 
How are these thing calibrated?

Thread

Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-10 10:26 -0700
  Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-10 10:33 -0700
  Re: Twin paradox article in Wikipedia Richard Hachel <r.hachel@frite.fr> - 2023-07-10 17:56 +0000
    Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-10 11:26 -0700
      Re: Twin paradox article in Wikipedia "mitchr...@gmail.com" <mitchrae3323@gmail.com> - 2023-07-10 14:27 -0700
        Re: Twin paradox article in Wikipedia Richard Hachel <r.hachel@frite.fr> - 2023-07-10 21:42 +0000
          Re: Twin paradox article in Wikipedia Gernaro Close <lcgr@rrlgrane.ne> - 2023-07-10 21:58 +0000
            Re: Twin paradox article in Wikipedia Richard Hachel <r.hachel@frite.fr> - 2023-07-10 22:12 +0000
            Re: Twin paradox article in Wikipedia Emanuele Pezos <leop@mmpussos.zm> - 2023-07-12 08:34 +0000
          Re: Twin paradox article in Wikipedia Volney <volney@invalid.invalid> - 2023-07-11 11:03 -0400
            Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-11 08:11 -0700
            Re: Twin paradox article in Wikipedia Wade Spyridis <didi@drdsippw.ss> - 2023-07-11 20:01 +0000
  Re: Twin paradox article in Wikipedia patdolan <patdolan@comcast.net> - 2023-07-10 15:14 -0700
    Re: Twin paradox article in Wikipedia Richard Hachel <r.hachel@frite.fr> - 2023-07-10 22:28 +0000
      Re: Twin paradox article in Wikipedia Harry Angelopoulos <ouse@assapoyr.ug> - 2023-07-10 22:34 +0000
      Re: Twin paradox article in Wikipedia patdolan <patdolan@comcast.net> - 2023-07-10 15:50 -0700
      Re: Twin paradox article in Wikipedia Athel Cornish-Bowden <athel.cb@gmail.com> - 2023-07-11 11:37 +0200
    Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-10 19:46 -0700
      Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-10 20:47 -0700
  Re: Twin paradox article in Wikipedia The Starmaker <starmaker@ix.netcom.com> - 2023-07-10 21:50 -0700
    Re: Twin paradox article in Wikipedia The Starmaker <starmaker@ix.netcom.com> - 2023-07-11 11:07 -0700
      Re: Twin paradox article in Wikipedia The Starmaker <starmaker@ix.netcom.com> - 2023-07-11 21:19 -0700
  Re: Twin paradox article in Wikipedia "Dono." <eggy20011951@gmail.com> - 2023-07-11 08:00 -0700
    Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-11 08:29 -0700
      Re: Twin paradox article in Wikipedia Maïkel Jacques-Sonne <mjs@frite.fr> - 2023-07-11 16:03 +0000
      Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-11 10:03 -0700
  Re: Twin paradox article in Wikipedia wugi <wugi@brol.invalid> - 2023-07-11 18:53 +0200
    Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-11 10:18 -0700
      Re: Twin paradox article in Wikipedia Richard Hachel <r.hachel@frite.fr> - 2023-07-11 17:38 +0000
      Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-11 10:39 -0700
        Re: Twin paradox article in Wikipedia Volney <volney@invalid.invalid> - 2023-07-12 23:34 -0400
          Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-12 22:29 -0700
            Re: Twin paradox article in Wikipedia Volney <volney@invalid.invalid> - 2023-07-13 09:11 -0400
              Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-13 06:27 -0700
      Re: Twin paradox article in Wikipedia wugi <wugi@brol.invalid> - 2023-07-12 17:32 +0200
        Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-12 09:05 -0700
          Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-12 09:46 -0700
          Re: Twin paradox article in Wikipedia wugi <wugi@brol.invalid> - 2023-07-12 19:07 +0200
            Re: Twin paradox article in Wikipedia Richard Hachel <r.hachel@frite.fr> - 2023-07-12 17:36 +0000
              Re: Twin paradox article in Wikipedia wugi <wugi@brol.invalid> - 2023-07-12 21:16 +0200
                Re: Twin paradox article in Wikipedia wugi <wugi@brol.invalid> - 2023-07-12 21:19 +0200
                Re: Twin paradox article in Wikipedia Richard Hachel <r.hachel@frite.fr> - 2023-07-12 19:47 +0000
  Re: Twin paradox article in Wikipedia larry harson <larryharson66@gmail.com> - 2023-07-11 11:30 -0700
    Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-11 12:02 -0700
  Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-12 07:19 -0700
    Re: Twin paradox article in Wikipedia "Dono." <eggy20011951@gmail.com> - 2023-07-12 08:32 -0700
      Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-12 13:24 -0700
        Re: Twin paradox article in Wikipedia "Dono." <eggy20011951@gmail.com> - 2023-07-12 20:43 -0700
          Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-13 01:31 -0700
            Re: Twin paradox article in Wikipedia "Dono." <eggy20011951@gmail.com> - 2023-07-13 07:14 -0700
              Re: Twin paradox article in Wikipedia "Dono." <eggy20011951@gmail.com> - 2023-07-13 08:31 -0700
                Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-13 09:13 -0700
                Re: Twin paradox article in Wikipedia "Dono." <eggy20011951@gmail.com> - 2023-07-13 12:16 -0700
                Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-13 20:49 -0700
                Re: Twin paradox article in Wikipedia "Dono." <eggy20011951@gmail.com> - 2023-07-13 21:03 -0700
                Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-13 21:33 -0700
                Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-14 01:09 -0700
                Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-24 17:08 -0700
              Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-13 09:49 -0700
        Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-13 04:30 -0700
          Re: Twin paradox article in Wikipedia nospam@de-ster.demon.nl (J. J. Lodder) - 2023-07-13 18:21 +0200
            Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-13 09:46 -0700
              Re: Twin paradox article in Wikipedia nospam@de-ster.demon.nl (J. J. Lodder) - 2023-07-15 21:37 +0200
                Re: Twin paradox article in Wikipedia Paul Alsing <pnalsing@gmail.com> - 2023-07-15 13:37 -0700
                Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-15 13:52 -0700
                Re: Twin paradox article in Wikipedia nospam@de-ster.demon.nl (J. J. Lodder) - 2023-07-16 12:03 +0200
                Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-16 03:54 -0700
                Re: Twin paradox article in Wikipedia nospam@de-ster.demon.nl (J. J. Lodder) - 2023-07-16 13:36 +0200
                Re: Twin paradox article in Wikipedia Tom Roberts <tjoberts137@sbcglobal.net> - 2023-07-16 09:03 -0500
                Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-16 07:18 -0700
                Re: Twin paradox article in Wikipedia Elizardo Sklavenitis <otrv@vzoeaioo.tk> - 2023-07-16 19:08 +0000
                Re: Twin paradox article in Wikipedia Meredith Adamou <utto@mddaeaem.tt> - 2023-07-16 18:55 +0000
                Re: Twin paradox article in Wikipedia RichD <r_delaney2001@yahoo.com> - 2023-07-17 11:49 -0700
                Re: Twin paradox article in Wikipedia nospam@de-ster.demon.nl (J. J. Lodder) - 2023-07-17 22:07 +0200
                Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-18 00:41 -0700
                Re: Twin paradox article in Wikipedia Tom Roberts <tjoberts137@sbcglobal.net> - 2023-07-18 22:49 -0500
                Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-18 21:06 -0700
                Re: Twin paradox article in Wikipedia Honorio Christakos <iosi@asrsosch.rc> - 2023-07-19 08:46 +0000
                Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-19 10:58 -0700
                Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-16 06:09 -0700
                Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-16 04:35 -0700
                Re: Twin paradox article in Wikipedia nospam@de-ster.demon.nl (J. J. Lodder) - 2023-07-15 23:29 +0200
                Re: Twin paradox article in Wikipedia Tom Roberts <tjoberts137@sbcglobal.net> - 2023-07-15 18:37 -0500
                Re: Twin paradox article in Wikipedia nospam@de-ster.demon.nl (J. J. Lodder) - 2023-07-16 12:03 +0200
                Re: Twin paradox article in Wikipedia Tom Roberts <tjoberts137@sbcglobal.net> - 2023-07-18 23:28 -0500
                Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-18 22:06 -0700
                Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-18 00:31 -0700
          Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-13 10:21 -0700
            Re: Twin paradox article in Wikipedia Prokaryotic Capase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2023-07-13 11:01 -0700
              Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-13 13:49 -0700
              Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-13 14:06 -0700
            Re: Twin paradox article in Wikipedia "Dono." <eggy20011951@gmail.com> - 2023-07-13 12:18 -0700
              Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-13 13:51 -0700
                Re: Twin paradox article in Wikipedia "Dono." <eggy20011951@gmail.com> - 2023-07-13 14:52 -0700
                Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-14 00:49 -0700
                Re: Twin paradox article in Wikipedia "Dono." <eggy20011951@gmail.com> - 2023-07-14 08:24 -0700
          Re: Twin paradox article in Wikipedia Lou <noelturntive@live.co.uk> - 2023-07-17 10:59 -0700
  Re: Twin paradox article in Wikipedia Mike Fontenot <mlfasf@comcast.net> - 2023-07-14 10:32 -0600
    Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-14 09:45 -0700
    Re: Twin paradox article in Wikipedia The Starmaker <starmaker@ix.netcom.com> - 2023-07-14 09:48 -0700
      Re: Twin paradox article in Wikipedia The Starmaker <starmaker@ix.netcom.com> - 2023-07-14 22:19 -0700
    Re: Twin paradox article in Wikipedia Tom Roberts <tjoberts137@sbcglobal.net> - 2023-07-15 13:07 -0500
      Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-15 11:15 -0700
      Re: Twin paradox article in Wikipedia Mike Fontenot <mlfasf@comcast.net> - 2023-07-16 11:45 -0600
        Re: Twin paradox article in Wikipedia whodat <whodaat@void.nowgre.com> - 2023-07-16 13:36 -0500
        Re: Twin paradox article in Wikipedia Tom Roberts <tjoberts137@sbcglobal.net> - 2023-07-16 22:19 -0500
          Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-16 21:26 -0700
    Re: Twin paradox article in Wikipedia Richard Hachel <r.hachel@frite.fr> - 2023-07-15 19:09 +0000
      Re: Twin paradox article in Wikipedia "Paul B. Andersen" <paul.b.andersen@paulba.no> - 2023-07-16 13:23 +0200
        Re: Twin paradox article in Wikipedia Maciej Wozniak <maluwozniak@gmail.com> - 2023-07-16 04:36 -0700
        Re: Twin paradox article in Wikipedia Richard Hachel <r.hachel@frite.fr> - 2023-07-16 13:08 +0000
          Re: Twin paradox article in Wikipedia Dallas Anetakis <aske@aaeeatli.as> - 2023-07-16 13:41 +0000
          Re: Twin paradox article in Wikipedia Athel Cornish-Bowden <athel.cb@gmail.com> - 2023-07-16 15:45 +0200

csiph-web