Wang / Sagnac Devices
in [Relativity]
|
Prev: Relativity ring problem - what shape is this?
Next: BUY CHEAP TEXTBOOKS | College Textbooks | Used Textbooks |
From: doug on 23 Oct 2009 17:51 Jonah Thomas wrote: > doug <xx(a)xx.com> wrote: > >>Jonah Thomas wrote: >> >>>doug <xx(a)xx.com> wrote: >>> >>>>Jonah Thomas wrote: >>> >>>>>When I started to pay attention to problems in Einstein's original >>>>>paper various people pointed me to a later Einstein paper which >>> >>>they>>said was better written and which cleared things up. If we've >>>had a>>hundred years to learn better how to derive SR and how to >>>teach it,>>and we are no better than Einstein in 1920, then something >>>is very>>wrong. >>> >>>>>In the last hundred years explanations have been found for the >>>>>various self-contradictions and failures of SR, so the problems >>> >>>have>>either been fixed or covered over. >>> >>>>There are no contradictions or failures of SR in its domain of >>>>applicability. There was nothing to fix. >>>> >>>> There's no need to pretent there were never any >>>>problems if the problems have been resolved. >>>> >>>>Point out a problem is you think there was one? >>> >>>To you? Whatever for? You would deny it and argue that it never >>>existed, you would misunderstand and confuse the issue. I have >>>better things to do than argue with fanatics. >>> >> >>So you have no problems to point out. I just wanted you to be clear >>on that. > > > Believe whatever you want. You will anyway. You are a fanatic who has > chosen what to believe and is not open to new information. It would be > silly for me to argue with you. So you just made the statement about problems in physics and cannot back it up. Why are you hiding? >
From: Jonah Thomas on 23 Oct 2009 18:13 HW@..(Henry Wilson DSc). wrote: > Jonah Thomas <jethomas5(a)gmail.com> wrote: > >Tom Roberts <tjrob137(a)sbcglobal.net> wrote: > >> tominlaguna(a)yahoo.com wrote: > > > >> I repeat: to analyze how light reflects from a mirror, you really > >need> to use the inertial frame in which the mirror is at rest when > >the> light reflects from it -- you don't know what happens for any > >other> case (and it is theory dependent). This means that for a > >mirror on a> rotating platform one must analyze a short light pulse, > >not a> continuous beam. > > > >Interesting thought! > > > >Light travels through a fiber optic cable at about 200,000 km/sec. So > >if you could do the Sagnac or Wang experiment with 2000 km of cable, > >you could get a time delay of about 0.01 second. Spin your spool of > >cable fast enough and you could see whether a short laser pulse > >arrives at the same time. > > > >It's no problem to get a spool with 1 km of cable. That gives you > >5*10^-6 seconds. How fast can you spin it? How short a laser pulse > >can you put through it? > > This is just what a ring (fibre optic) gyro does...but it uses fringe > displacement rather than travel time. Sure, but it may be possible to measure travel time. When it's fringe displacment you get a useful result but people argue about what it means. If you can actually measure travel time with the light coming in both directions from a laser cavity, then you can directly test emission theory in the most definitive sense. If you can make the pulse short enough that a delayed path wouldn't interfere at all, then the presence of interference would indicate the light was not delayed as much as expected. The absence of interference would indicate the light did not arrive simultaneously from both paths. A direct measure of the time would be interesting too. Unfortunately, light that travels long distances in fiber optic cables suffers dispersion etc which must be handled, and that presents a complication which might change the results.
From: doug on 23 Oct 2009 19:43 Jonah Thomas wrote: > HW@..(Henry Wilson DSc). wrote: > >>Jonah Thomas <jethomas5(a)gmail.com> wrote: >> >>>Tom Roberts <tjrob137(a)sbcglobal.net> wrote: >>> >>>>tominlaguna(a)yahoo.com wrote: >>> >>>>I repeat: to analyze how light reflects from a mirror, you really >>> >>>need> to use the inertial frame in which the mirror is at rest when >>>the> light reflects from it -- you don't know what happens for any >>>other> case (and it is theory dependent). This means that for a >>>mirror on a> rotating platform one must analyze a short light pulse, >>>not a> continuous beam. >>> >>>Interesting thought! >>> >>>Light travels through a fiber optic cable at about 200,000 km/sec. So >>>if you could do the Sagnac or Wang experiment with 2000 km of cable, >>>you could get a time delay of about 0.01 second. Spin your spool of >>>cable fast enough and you could see whether a short laser pulse >>>arrives at the same time. >>> >>>It's no problem to get a spool with 1 km of cable. That gives you >>>5*10^-6 seconds. How fast can you spin it? How short a laser pulse >>>can you put through it? >> >>This is just what a ring (fibre optic) gyro does...but it uses fringe >>displacement rather than travel time. > > > Sure, but it may be possible to measure travel time. When it's fringe > displacment you get a useful result but people argue about what it > means. If you can actually measure travel time with the light coming in > both directions from a laser cavity, then you can directly test emission > theory in the most definitive sense. If you can make the pulse short > enough that a delayed path wouldn't interfere at all, then the presence > of interference would indicate the light was not delayed as much as > expected. The absence of interference would indicate the light did not > arrive simultaneously from both paths. A direct measure of the time > would be interesting too. > > Unfortunately, light that travels long distances in fiber optic cables > suffers dispersion etc which must be handled, and that presents a > complication which might change the results. When I was involved with fiber optic gyros years ago, we found out that this was not an issue. You can look at the changge in n with frequency and from the laser line width, you can calculate the effect to be small. A bigger effect is birefringence.
From: Androcles on 23 Oct 2009 19:38 "Jonah Thomas" <jethomas5(a)gmail.com> wrote in message news:20091023181332.419616f3.jethomas5(a)gmail.com... > HW@..(Henry Wilson DSc). wrote: >> Jonah Thomas <jethomas5(a)gmail.com> wrote: >> >Tom Roberts <tjrob137(a)sbcglobal.net> wrote: >> >> tominlaguna(a)yahoo.com wrote: >> > >> >> I repeat: to analyze how light reflects from a mirror, you really >> >need> to use the inertial frame in which the mirror is at rest when >> >the> light reflects from it -- you don't know what happens for any >> >other> case (and it is theory dependent). This means that for a >> >mirror on a> rotating platform one must analyze a short light pulse, >> >not a> continuous beam. >> > >> >Interesting thought! >> > >> >Light travels through a fiber optic cable at about 200,000 km/sec. So >> >if you could do the Sagnac or Wang experiment with 2000 km of cable, >> >you could get a time delay of about 0.01 second. Spin your spool of >> >cable fast enough and you could see whether a short laser pulse >> >arrives at the same time. >> > >> >It's no problem to get a spool with 1 km of cable. That gives you >> >5*10^-6 seconds. How fast can you spin it? How short a laser pulse >> >can you put through it? >> >> This is just what a ring (fibre optic) gyro does...but it uses fringe >> displacement rather than travel time. > > Sure, but it may be possible to measure travel time. When it's fringe > displacment you get a useful result but people argue about what it > means. If you can actually measure travel time with the light coming in > both directions from a laser cavity, then you can directly test emission > theory in the most definitive sense. If you can make the pulse short > enough that a delayed path wouldn't interfere at all, then the presence > of interference would indicate the light was not delayed as much as > expected. The absence of interference would indicate the light did not > arrive simultaneously from both paths. A direct measure of the time > would be interesting too. > > Unfortunately, light that travels long distances in fiber optic cables > suffers dispersion etc which must be handled, and that presents a > complication which might change the results. Ok, so you've qualified it. Now quantify it.
From: Tom Roberts on 23 Oct 2009 21:16
Jonah Thomas wrote: > Light travels through a fiber optic cable [...] This is done all the time. Look up fiber optic gyroscope. The results confirm the prediction of SR. The results refute any ballistic theory. The results limit the form of an aether theory; when combined with all the other experiments, no classical aether theory remains viable. Tom Roberts |