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Re: One way speed of light

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Thomas Heger <ttt_heg@web.de> writes:

>Am 29.11.2018 um 22:21 schrieb Libor Striz:
>> Thomas Heger <ttt_heg@web.de> Wrote in message:
>> 
>>> I would say, the difference (in two way speed of light) is beyond what
>>> we could measure even today.
>> 
>> If what you say is true,
>> the classical  prediction for MMX
>> in 1881 and 1887
>> would be zero result
>> and Michelson would bother to test it.

>There was a much enhanced version of the MMX by Kennedy and Thorndike 
>(if I spell that correctly).

>They did a LOT of things to keep expected influences away from the 
>apparatus.

>E.g. they evacuated the interferometer and kept it a constant 
>temperature by a difference of less then 0.001 degree.

>They estimated an effect of about 1/1000 of a fringe due to an eventual 
>'ether wind'.

If they wanted to, the LIGO detectors, which are essentially giant super
accurate MMX experiments fixed to the earth, could be used to look for
this aether wind.  However, since it is essentially settled science that
the speed of light is fixed, nobody is going to waste the effort doing
this.

>The original experiment was not remotely as precise and they could not 
>possibly measure anything at all.

>The problem is:

>the difference between v=c-x on the way to the mirror and v=c-x on the 
>way back would cancel out, if the relation between speed of light and 
>speed of the 'ether' is very large.

Wrong. The whole basis behind the MMX experiment was that the harmonic
mean speed from c+v and c-v COULD be detected. It would produce a speed
difference from c for the two-way trip. The speed couldn't be measured
directly but indirectly by producing fringe shifts.

>That is like trying to measure the pace of a snail from the ISS.

Don't forget the LIGO apparatus, a giant MMX experiment, is measuring
changes a fraction of the diameter of a proton over a few km arms length.
Compared to that, tracking the snail's speed would be child's play.

>Or: in the example with swimming up and down a river, the measurable 
>effect stems from the difference in time in the way up to way down.

>But 2,2 km is extremely small in comparison to what light could pass in 
>one second. That is as if the river is flowing slower than hair grows.

>How could you decide, whether or not the hair grows independent of the 
>movement or not?

Scientists have to be (and frequently are) creative in doing things like
that. Michelson and Morley measuring such a tiny deviation from c in the
round trip speed of light by fringe shifts, rather than by direct
measurement, was brilliant. Especially with late 1800s technology.
Although they were famous for 'failure', they indirectly succeeded in 
showing that light does not move at c+v one way and c-v on return.

>> Have you asked yourself the question why it was expected to be
>> measurable ?

>Don't know..

Because they were very clever at finding a way.

>>> Another serious problem arises, if you try to define the second
>>> independent from the rotation of the Earth.
>>>
>>> We actually base our measurements and their units on our usual
>>> environment and that is obviously rotating with the Earth.
>> 
>> Where have you been in last 51 years ?
>> As since 1967, second is not defined by the Earth rotation
>> and the mean day length does not last  exactly 86400 s any more.
>> 
>> Read about the leap second.
>>>
>>> IOW: in respect to what do we want to measure the velocity of such an
>>> 'ether wind'?
>> 
>> The Earth is  moving through the supposed aether
>> there and back by cca 30 km/s.
>> That is some wind.

>Well, yes, but if you compare it with the speed  of light, 30 km/s is 
>not that fast.

0.0001c.  Certainly measurable with good science techniques.

>Yes. But my question was about the velocity of the 'ether' (not the 
>definition of the second).

>In respect to what should the velocity of such an ether be measured (and 
>why?) ?

In M-M, with respect to the earth.

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One way speed of light Thomas Heger <ttt_heg@web.de> - 2018-11-26 16:01 +0100
  Re: One way speed of light Lee Primer <itoo@wodinwnc.cg> - 2018-11-26 15:50 +0000
  Re: One way speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-26 21:48 +0100
    Re: One way speed of light "David (Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2018-11-27 07:07 -0800
      Re: One way speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-29 02:09 +0100
  Re: One way speed of light JanPB <filmart@gmail.com> - 2018-11-26 13:04 -0800
    Re: One way speed of light Odd Bodkin <bodkinodd@gmail.com> - 2018-11-26 21:29 +0000
      Re: One way speed of light Thomas Heger <ttt_heg@web.de> - 2018-11-27 15:31 +0100
        Re: One way speed of light Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com.INVALID> - 2018-11-27 15:59 +0100
          Re: One way speed of light Thomas Heger <ttt_heg@web.de> - 2018-11-27 16:26 +0100
            Re: One way speed of light moroney@world.std.spaamtrap.com (Michael Moroney) - 2018-11-27 16:47 +0000
            Re: One way speed of light Odd Bodkin <bodkinodd@gmail.com> - 2018-11-27 16:54 +0000
            Re: One way speed of light Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com.INVALID> - 2018-11-27 18:01 +0100
          Re: One way speed of light Lee Primer <itoo@wodinwnc.cg> - 2018-11-28 00:55 +0000
            Re: One way speed of light Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com.INVALID> - 2018-11-28 05:14 +0100
              Re: One way speed of light Lee Primer <itoo@wodinwnc.cg> - 2018-11-28 15:13 +0000
        Re: One way speed of light Odd Bodkin <bodkinodd@gmail.com> - 2018-11-27 16:44 +0000
          Re: One way speed of light Thomas Heger <ttt_heg@web.de> - 2018-11-28 16:34 +0100
            Re: One way speed of light Lee Primer <itoo@wodinwnc.cg> - 2018-11-28 15:40 +0000
            Re: One way speed of light Odd Bodkin <bodkinodd@gmail.com> - 2018-11-28 17:20 +0000
              Re: One way speed of light Thomas Heger <ttt_heg@web.de> - 2018-11-29 20:43 +0100
                Re: One way speed of light Odd Bodkin <bodkinodd@gmail.com> - 2018-11-29 20:53 +0000
                Re: One way speed of light Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com.INVALID> - 2018-11-29 22:21 +0100
                Re: One way speed of light Thomas Heger <ttt_heg@web.de> - 2018-11-30 21:15 +0100
                Re: One way speed of light moroney@world.std.spaamtrap.com (Michael Moroney) - 2018-11-30 22:46 +0000
                Re: One way speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2018-11-30 17:23 -0600
                Re: One way speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-12-01 00:34 +0100
                Re: One way speed of light Odd Bodkin <bodkinodd@gmail.com> - 2018-11-30 23:40 +0000
                Re: One way speed of light Thomas Heger <ttt_heg@web.de> - 2018-12-01 16:17 +0100
                Re: One way speed of light "Dono," <sa_ge@comcast.net> - 2018-12-01 07:32 -0800
                Re: One way speed of light Thomas Heger <ttt_heg@web.de> - 2018-12-02 13:50 +0100
                Re: One way speed of light Gary Harnagel <hitlong@yahoo.com> - 2018-12-02 05:11 -0800
                Re: One way speed of light Thomas Heger <ttt_heg@web.de> - 2018-12-03 12:23 +0100
                Re: One way speed of light Odd Bodkin <bodkinodd@gmail.com> - 2018-12-03 18:53 +0000
                Re: One way speed of light mitchrae3323@gmail.com - 2018-12-03 11:25 -0800
                Re: One way speed of light Thomas Heger <ttt_heg@web.de> - 2018-12-04 13:04 +0100
                Re: One way speed of light Gary Harnagel <hitlong@yahoo.com> - 2018-12-03 11:57 -0800
                Re: One way speed of light alsor@interia.pl - 2018-12-03 13:28 -0800
                Re: One way speed of light mitchrae3323@gmail.com - 2018-12-03 13:56 -0800
                Re: One way speed of light alsor@interia.pl - 2018-12-03 14:13 -0800
                Re: One way speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-12-02 14:44 +0100
                Re: One way speed of light "Dono," <sa_ge@comcast.net> - 2018-12-02 07:13 -0800
                Re: One way speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2018-12-02 10:28 -0600
                Re: One way speed of light Mole Santiago <msb@awwnuvs.an> - 2018-12-02 18:42 +0000
                Re: One way speed of light alsor@interia.pl - 2018-12-02 11:08 -0800
                Re: One way speed of light moroney@world.std.spaamtrap.com (Michael Moroney) - 2018-12-02 18:49 +0000
                Re: One way speed of light Mole Santiago <msb@awwnuvs.an> - 2018-12-02 18:57 +0000
                Re: One way speed of light Mole Santiago <msb@awwnuvs.an> - 2018-12-02 18:58 +0000
                Re: One way speed of light Odd Bodkin <bodkinodd@gmail.com> - 2018-12-02 21:23 +0000
                Re: One way speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-12-01 18:20 +0100
                Re: One way speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2018-11-29 16:03 -0600
                Re: One way speed of light mlwozniak@wp.pl - 2018-11-29 15:03 -0800
                Re: One way speed of light Thomas Heger <ttt_heg@web.de> - 2018-11-30 21:18 +0100
                Re: One way speed of light Odd Bodkin <bodkinodd@gmail.com> - 2018-12-01 15:43 +0000
                Re: One way speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-12-02 14:58 +0100
                Re: One way speed of light moroney@world.std.spaamtrap.com (Michael Moroney) - 2018-11-29 23:38 +0000
                Re: One way speed of light mlwozniak@wp.pl - 2018-11-29 16:40 -0800
                Re: One way speed of light Odd Bodkin <bodkinodd@gmail.com> - 2018-11-30 03:22 +0000
                Re: One way speed of light benj <benj.fake@gmail.com> - 2018-11-29 22:41 -0500
                Re: One way speed of light Odd Bodkin <bodkinodd@gmail.com> - 2018-11-30 12:13 +0000
                Re: One way speed of light Thomas Heger <ttt_heg@web.de> - 2018-11-30 21:21 +0100
                Re: One way speed of light Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com.INVALID> - 2018-11-30 22:10 +0100
                Re: One way speed of light Thomas Heger <ttt_heg@web.de> - 2018-12-01 16:26 +0100
                Re: One way speed of light moroney@world.std.spaamtrap.com (Michael Moroney) - 2018-11-30 23:01 +0000
                Re: One way speed of light Odd Bodkin <bodkinodd@gmail.com> - 2018-11-30 23:03 +0000
                Re: One way speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-12-01 00:43 +0100
            Re: One way speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-29 02:01 +0100
            Re: One way speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-11-29 02:04 +0100
  Re: One way speed of light alsor@interia.pl - 2018-11-26 15:51 -0800
    Re: One way speed of light Gary Harnagel <hitlong@yahoo.com> - 2018-11-26 18:53 -0800
      Re: One way speed of light alsor@interia.pl - 2018-11-27 09:49 -0800
  Re: One way speed of light numbernumber1964@gmail.com - 2018-11-28 15:11 -0800
  Re: One way speed of light mitchrae3323@gmail.com - 2018-11-29 14:19 -0800
  Re: One way speed of light carleto4157990662@gmail.com - 2018-11-29 14:36 -0800
    Re: One way speed of light benj <benj.fake@gmail.com> - 2018-11-29 22:28 -0500
    Re: One way speed of light mitchrae3323@gmail.com - 2018-11-29 20:08 -0800
  Re: One way speed of light carleto4157990662@gmail.com - 2018-11-29 15:10 -0800
  Re: One way speed of light alsor@interia.pl - 2018-11-30 12:48 -0800
    Alex Sorokin, persistent imbecile "Dono," <sa_ge@comcast.net> - 2018-12-01 07:34 -0800

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