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Groups > sci.physics.relativity > #478431
| From | Thomas Heger <ttt_heg@web.de> |
|---|---|
| Newsgroups | sci.physics.relativity |
| Subject | Re: One way speed of light |
| Date | 2018-11-29 20:43 +0100 |
| Message-ID | <g6atr4Fqqu8U1@mid.individual.net> (permalink) |
| References | (2 earlier) <pthokn$1v5o$2@gioia.aioe.org> <g652qdFi448U1@mid.individual.net> <ptjs95$1e1r$2@gioia.aioe.org> <g67qrbF68otU1@mid.individual.net> <ptmipq$4pd$1@gioia.aioe.org> |
Am 28.11.2018 um 18:20 schrieb Odd Bodkin: > Thomas Heger <ttt_heg@web.de> wrote: >> Am 27.11.2018 um 17:44 schrieb Odd Bodkin: >>> Thomas Heger <ttt_heg@web.de> wrote: >>>> Am 26.11.2018 um 22:29 schrieb Odd Bodkin: >>>> >>>>>>> This two way measurement could easily cancel out any effect (with or >>>>>>> without an ether) because acceleration of one trip would be balanced by >>>>>>> deceleration on the way back. >>>>>> >>>>>> No, actually. It's a high-school-level exercise to see that this is not so. >>>>>> >>>>>> -- >>>>>> Jan >>>>>> >>>>> >>>>> 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 >>> >>> And is his average speed 3 miles per hour? Yes or no? >> >> >> How could you STILL use miles? >> >> >> There average is not 3 miles per hour, since you make an average as >> distance traveled by time needed. > > Exactly. > > And for the same reason, if you have a 2-way light speed measurement such > as the MMX, then even if there were a luminiferous ether that the apparatus > was moving through, so that upstream speed is c-v and downstream speed is > c+v, the average speed for the round trip will not be c. > > Thus, though this was not technically available in 1887, it is now quite > easily attainable to simply do a 2-way light traverse over, say, a couple > hundred meters and TIME the flight of a light pulse and see if the time is > different than c. Because if there were an ether that the apparatus was > moving through with speed v, you’d expect to measure an average speed of c’ > = c(1-(v/c)^2). For v/c = 1/20, then c’ would differ from c by 1/4%, which > for a total distance of, say, 400 m, corresponds to a time resolution of > 3ns, which is VERY doable. No one does it today of course, because the > matter is already settled. But YOU could do it with a pulsed laser in a > long darkened pipe with a couple mirrors, a photodiode, and an > oscilloscope. Light moves round the Earth 7.5 times per second and Earth rotates once per day. The ratio is WAY smaller than 1/20. E.g: we have 86400 s per day to travel 40,000 km (for one rotation along the equator - for instance). That is 2,16 km/s. 2,16/300,000= 0,0000072 The error between a river at rest and a river flowing slowly (or in this case Earth rotating or not) is similar to a VERY narrow triangle, which is not exactly symmetric, but slightly lopsided. The difference is obviously dependent on the geometry of such a triangle or in this case on the ration between speed of light and rotational velocity of the Earth. I would say, the difference (in two way speed of light) is beyond what we could measure even today. 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. So there is a conceptual difficulty to define space and time without reference to our home planet. IOW: in respect to what do we want to measure the velocity of such an 'ether wind'? Earth rotation seems fine, but is not all that Earth moves relative to. So: if rotation is not good enough, then what is? TH
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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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