Groups > sci.physics.relativity > #478262

Re: One way speed of light

From	moroney@world.std.spaamtrap.com (Michael Moroney)
Newsgroups	sci.physics.relativity
Subject	Re: One way speed of light
Date	2018-11-27 16:47 +0000
Organization	The World : www.TheWorld.com : Since 1989
Message-ID	<ptjsf6$5m3$2@pcls7.std.com> (permalink)
References	(1 earlier) <51d502aa-5dd2-4028-9712-80c759933c5c@googlegroups.com> <pthokn$1v5o$2@gioia.aioe.org> <g652qdFi448U1@mid.individual.net> <ptjm4c$cgb$1@dont-email.me> <g6560nFiqfdU1@mid.individual.net>

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Thomas Heger <ttt_heg@web.de> writes:

>>>> To wit:
>>>> Jimmy can swim at 3 miles per hour with respect to the water. Jimmy decides
>>>> to swim in a river that has a current of 1 mile per hour. He swims upstream
>>>> a quarter mile relative to the shore, and then he turns around and swims
>>>> downstream a quarter mile to his starting point at the shore, a total of a
>>>> half mile swum. What is his average speed relative to the shore for the
>>>> trip?
>>>>
>>>
>>>
>>> The swimmer swims faster downstream and slower upstream, because we had
>>> to add the velocity of the water in one case and subtract it in the other.
>>>
>>> The time is an eighth of an hour up and a sixteenth downstream and that
>>> is 675 seconds for a half mile. The result is roughly 1.19 m/s
>>>
>> The point is, the total time up and downstream,
>> and therefore the average speed  as well,
>> depends on the stream speed.

>Yes, but the  mean speed is not really interesting.

>Instead you could compare the 'momentary mean velocity'.

Odd's point is that the total speed or travel time depends on the speed
of the river.

>That is
>v_mean_ momentary= (speed upstream + speed downstream) /2

>and this is independent from the speed of the water.

And is _wrong_.

This is what trips up those who believe that light moves at c+v in one
direction and c-v on the return trip and therefore they say light moves at
c overall for the round trip because the v's cancel. If this (light moving
at c+v/c-v) were true, the overall time is always _less than_ c, as long
as v is nonzero.

Michelson/Morley knew this. They expected that for certain alignments of
their apparatus, light along one path would travel at c+v one way and c-v
on the return trip and they'd get a fringe shift from light on the right
angle path (c both ways). From the amount of shift they could determine
v (the aether wind speed).  Because light actually traveled at c all the
time, they always got a null result (v=0 no matter how their apparatus
happened to be aligned in space).

Thread

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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