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Re: Very basic question about velocities, speed of light, and reference frames

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On 8/26/2015 4:15 PM, Y wrote:
> "How fast is the light beam approaching object OB as observed from Reference frame A?"
>
> An observer cannot observe a light beam approaching them. That would be like saying that
> something FTL is projecting from the light as it moves towards you.
>
> -y

I think you are stuck in this rather silly notion that an observer is 
one pair of eyes sitting in one place watching things happen around him.

In science, an observer means a laboratory, or if you like, an 
experimental setup.

So imagine a set-up where you have two scintillator paddles and 
associated PMTs and electronics, separated by 1500 meters. They are at 
rest relative to each other, tied down to some common structure 
connecting the two. This in science is ONE observer. And so with this, 
this observer can very well measure the approach speed of the speed of 
light. This observer takes the digitized and time-stamped signals from 
both scintillators and uses that to measure the time of flight of the 
pulse of light. This same observer knows the distance between them, and 
so can simply calculate distance/time to get the speed.

Once again, you have been stymied by having a completely different 
understanding of words as they are used by physicists. Your 
understanding of "observer" says such a thing is impossible, where for a 
physicist's understanding of that word, it is not only completely 
possible but routinely done.


-- 
Odd Bodkin --- maker of fine toys, tools, tables

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Very basic question about velocities, speed of light, and reference frames Jon Price <jonelwoodprice@gmail.com> - 2015-08-13 08:47 -0700
  Re: Very basic question about velocities, speed of light, and reference frames Odd Bodkin <bodkinodd@gmail.com> - 2015-08-13 10:51 -0500
    Re: Very basic question about velocities, speed of light, and reference frames kenseto <setoken@att.net> - 2015-08-17 19:00 -0700
      Re: Very basic question about velocities, speed of light, and reference frames Odd Bodkin <bodkinodd@gmail.com> - 2015-08-24 09:35 -0500
        Re: Very basic question about velocities, speed of light, and reference frames Poutnik <Poutnik4NNTP@gmail.com> - 2015-08-24 16:39 +0200
      Re: Very basic question about velocities, speed of light, and reference frames pcardinale@volcanomail.com - 2015-08-26 13:10 -0700
  Re: Very basic question about velocities, speed of light, and reference frames Maciej Woźniak <mlwozniak@wp.pl> - 2015-08-13 17:52 +0200
    Re: Very basic question about velocities, speed of light, and reference frames Jon Price <jonelwoodprice@gmail.com> - 2015-08-13 09:23 -0700
  Re: Very basic question about velocities, speed of light, and reference frames John Heath <heathjohn2@gmail.com> - 2015-08-14 06:08 -0700
    Re: Very basic question about velocities, speed of light, and reference frames Jon Price <jonelwoodprice@gmail.com> - 2015-08-14 08:15 -0700
      Re: Very basic question about velocities, speed of light, and reference frames Maciej Woźniak <mlwozniak@wp.pl> - 2015-08-14 17:33 +0200
        Re: Very basic question about velocities, speed of light, and reference frames Jon Price <jonelwoodprice@gmail.com> - 2015-08-14 08:35 -0700
          Re: Very basic question about velocities, speed of light, and reference frames Maciej Woźniak <mlwozniak@wp.pl> - 2015-08-14 18:24 +0200
            Re: Very basic question about velocities, speed of light, and reference frames Tom Roberts <tjroberts137@sbcglobal.net> - 2015-08-14 12:48 -0500
              Re: Very basic question about velocities, speed of light, and reference frames Maciej Woźniak <mlwozniak@wp.pl> - 2015-08-14 20:28 +0200
                Re: Very basic question about velocities, speed of light, and reference frames JanPB <filmart@gmail.com> - 2015-08-14 11:54 -0700
                Re: Very basic question about velocities, speed of light, and reference frames Maciej Woźniak <mlwozniak@wp.pl> - 2015-08-14 21:22 +0200
                Re: Very basic question about velocities, speed of light, and reference frames alsor@interia.pl - 2015-08-14 12:26 -0700
                Re: Very basic question about velocities, speed of light, and reference frames JanPB <filmart@gmail.com> - 2015-08-14 13:10 -0700
                Re: Very basic question about velocities, speed of light, and reference frames Maciej Woźniak <mlwozniak@wp.pl> - 2015-08-14 22:22 +0200
                Re: Very basic question about velocities, speed of light, and reference frames JanPB <filmart@gmail.com> - 2015-08-14 14:17 -0700
                Re: Very basic question about velocities, speed of light, and reference frames Maciej Woźniak <mlwozniak@wp.pl> - 2015-08-15 07:46 +0200
                Re: Very basic question about velocities, speed of light, and reference frames JanPB <filmart@gmail.com> - 2015-08-15 01:23 -0700
                Re: Very basic question about velocities, speed of light, and reference frames Maciej Woźniak <mlwozniak@wp.pl> - 2015-08-15 11:37 +0200
                Re: Very basic question about velocities, speed of light, and reference frames alsor@interia.pl - 2015-08-15 14:46 -0700
                Re: Very basic question about velocities, speed of light, and reference frames JanPB <filmart@gmail.com> - 2015-08-16 18:58 -0700
                Re: Very basic question about velocities, speed of light, and reference frames alsor@interia.pl - 2015-08-17 10:52 -0700
                Re: Very basic question about velocities, speed of light, and reference frames JanPB <filmart@gmail.com> - 2015-08-26 14:28 -0700
      Re: Very basic question about velocities, speed of light, and reference frames Odd Bodkin <bodkinodd@gmail.com> - 2015-08-14 10:44 -0500
      Re: Very basic question about velocities, speed of light, and reference frames Tom Roberts <tjroberts137@sbcglobal.net> - 2015-08-14 12:44 -0500
        Re: Very basic question about velocities, speed of light, and reference frames alsor@interia.pl - 2015-08-14 12:14 -0700
        Re: Very basic question about velocities, speed of light, and reference frames John Gogo <jfgogo22@yahoo.com> - 2015-08-14 19:44 -0700
          Re: Very basic question about velocities, speed of light, and reference frames John Gogo <jfgogo22@yahoo.com> - 2015-08-14 19:46 -0700
      Re: Very basic question about velocities, speed of light, and reference frames Mikko <mikko.levanto@outlook.com> - 2015-08-16 14:59 +0300
        Re: Very basic question about velocities, speed of light, and reference frames Maciej Woźniak <mlwozniak@wp.pl> - 2015-08-16 14:02 +0200
        Re: Very basic question about velocities, speed of light, and reference frames Eteocles Panagakos <eteoclespd@prospernetwork.org> - 2015-08-16 12:37 +0000
          Re: Very basic question about velocities, speed of light, and reference frames Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 15:44 +0200
            Re: Very basic question about velocities, speed of light, and reference frames Eteocles Panagakos <eteoclespd@prospernetwork.org> - 2015-08-16 13:53 +0000
              Re: Very basic question about velocities, speed of light, and reference frames Poutnik <poutnik4nntp@gmail.com> - 2015-08-16 16:16 +0200
      Re: Very basic question about velocities, speed of light, and reference frames John Heath <heathjohn2@gmail.com> - 2015-08-16 19:43 -0700
        Re: Very basic question about velocities, speed of light, and reference frames fuller.david@hotmail.com - 2015-08-26 12:08 -0700
          Re: Very basic question about velocities, speed of light, and reference frames fuller.david@hotmail.com - 2015-08-26 13:32 -0700
            Re: Very basic question about velocities, speed of light, and reference frames fuller.david@hotmail.com - 2015-08-26 13:39 -0700
    Re: Very basic question about velocities, speed of light, and reference frames Y <yanarchi@hotmail.com> - 2015-08-26 14:22 -0700
      Re: Very basic question about velocities, speed of light, and reference frames Odd Bodkin <bodkinodd@gmail.com> - 2015-08-26 16:29 -0500
  Re: Very basic question about velocities, speed of light, and reference frames Y <yanarchi@hotmail.com> - 2015-08-26 14:15 -0700
    Re: Very basic question about velocities, speed of light, and reference frames Odd Bodkin <bodkinodd@gmail.com> - 2015-08-26 16:27 -0500
      Re: Very basic question about velocities, speed of light, and reference frames Y <yanarchi@hotmail.com> - 2015-08-27 19:31 -0700
        Re: Very basic question about velocities, speed of light, and reference frames Odd Bodkin <bodkinodd@gmail.com> - 2015-08-28 07:55 -0500

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