Is the Sagnac effect a valid argument against Relativity?

[wisp]

You are an observer fixed in absolute space watching clocks pass between two points, A and B, separated by 1km. The moving clocks are identical in every way, and have observers aboard.

The Sagnac clock observer is traveling at a speed of 1km/s in a circular orbit (radius 1 billion light years), so its path between A and B appears as a straight line. And the Sagnac effect requires that the speed of light must be c+v and c-v respectively (if the Sagnac observer recorded the speed of light as c, then he would not be moving in a circle).

According to Relativity the Inertial clock observer - who is traveling in a straight line at 1km/s - records the speed of light as being c.

You are not told which clock will pass by, but when they pass you cannot distinguish the two apart. And both clocks follow the same straight line, as your measuring device cannot detect any error in their paths.

The case against Relativity is this:
It is an experimentally proven fact that the Sagnac observer measures the speed of light as c+v and c-v. Otherwise the Sagnac effect would not be observed. But according to Relativity, what appears to be an identically moving observer measures the speed of light a c.

Since we cannot distinguish between the moving clock observers in this case, they must both measure the speed of light as being the same. And it is clear that Relativity is at fault and the one-way speed of light is not c, but either c+v or c-v.

 

[AlphaNumeric]

http://en.wikipedia.org/wiki/Sagnac_effect

It mentions relativity too, and a quick search on these forums will bring up plenty of discussion about this effect and relativity. Suffice to say, it doesn't seem you bothered researching it much because you'd have found an explanation to your conundrum within a few minutes.

 

[ZapperZ]

I could cite tons of papers that make use of the Sagnac effect without having to attribute it to ANY of what you mentioned - there IS a significant leap in attributing the phase shift to a change in velocity - but I'll just cite a few and ask you directly why you ignore such sources:

1. G B Malykin, "The Sagnac effect: correct and incorrect explanations", PHYS-USP, 43, 1229-1252 (2000).

2. E.J. Post Rev. Mod. Phys. 39, 475–493 (1967).

3. R. Anderson et al. Am. J. Phys 62, 975-985 (1994).

4. W.A. Rodriguez and M. Sharif., Found. Phys. 31, 1767 (2001).

Zz.

 

[pervect]

You are an observer fixed in absolute space

There's no operational way to tell if you're "fixed" or "moving" with respect to absoute space. The words here are empty of meaning except to someone who has already decided to believe in some sort of ether theory.

watching clocks pass between two points, A and B, separated by 1km. The moving clocks are identical in every way, and have observers aboard.

The Sagnac clock observer is traveling at a speed of 1km/s in a circular orbit (radius 1 billion light years), so its path between A and B appears as a straight line.

But it's not really straight, is it?

And the Sagnac effect requires that the speed of light must be c+v and c-v respectively (if the Sagnac observer recorded the speed of light as c, then he would not be moving in a circle).

You are a bit confused here.

The moving observer has a choice - he can use standard Einsteinian clock synchronization, in which case the speed of light will be equal to c in all directions.

Or, he can abandon Einsteinian clock synchorinzation to use a different coordiante system. If he does this:

1) the "speed" of light will not be c (in these coordinates, defining speed as the rate of change of the distance coordinate with respect to the time coordinate).

2) SR won't work anymore.

3) Newton's laws won't work anymore either (Newton's laws also require Einsteinian clock synchronization!)

4) GR still works fine (GR is capable of dealing with arbitrary coordinate systems )

There is nothing about moving in a gentle arc that "forces" a person moving in a gentle arc to use non-Einsteinian clock synchronization however. It's a choice they have to make for themselves.

The case against Relativity is this:
It is an experimentally proven fact that the Sagnac observer measures the speed of light as c+v and c-v.

This is incorrect, though it is unfortunately possible to find such incorrect statements in the literature by a few authors.

To add another paper to the list already cited as to why this is incorrect (this paper is online, but may not be the easiest read on the topic)

http://arxiv.org/abs/gr-qc/9805089

It is often taken for granted that on board a rotating disk it is possible to operate a \QTR{it}{global}3+1 splitting of space-time, such that both lengths and time intervals are \QTR{it}{uniquely} defined in terms of measurements performed by real rods and real clocks at rest on the platform. This paper shows that this assumption, although widespread and apparently trivial, leads to an anisotropy of the velocity of two light beams traveling in opposite directions along the rim of the disk; which in turn implies some recently pointed out paradoxical consequences undermining the self-consistency of the Special Theory of Relativity (SRT). A correct application of the SRT solves the problem and recovers complete internal consistency for the theory. As an immediate consequence, it is shown that the Sagnac effect only depends on the non homogeneity of time on the platform and has nothing to do with any anisotropy of the speed of light along the rim of the disk, contrary to an incorrect but widely supported idea.

(Emphasis added by me)

 

[clj4]

And it is clear that Relativity is at fault and the one-way speed of light is not c, but either c+v or c-v.

Still trying , aren't you.
After it has been explained to you ad nauseam here:

http://www.bautforum.com/showthread.php?t=36020

and here:

http://www.bautforum.com/showthread.php?t=38545

 

[AlphaNumeric]

After it has been explained to you ad nauseam here:

http://www.bautforum.com/showthread.php?t=36020

Considering wisp in that thread quotes someone's Wiki contribution he's obviously used Wiki a fair bit, yet clearly ignored the actual Sagnac article which talks about how the effect meshes with relativity.

When in doubt, put your fingers in your ears, close your eyes and hum real loud ;)

I've got to admit though, Wisp has gone a lot further into attempting to do the maths of relativity than other 'Relativity is wrong, I'm right' cranks I've come across. Still, definitely ignoring things infront of his face.

 

[leandros_p]

...(if the Sagnac observer recorded the speed of light as c, then he would not be moving in a circle).

...It is an experimentally proven fact that the Sagnac observer measures the speed of light as c+v and c-v.
...Since we cannot distinguish between the moving clock observers in this case, they must both measure the speed of light as being the same. And it is clear that Relativity is at fault and the one-way speed of light is not c, but either c+v or c-v.

You must try to understand the difference bettween "apparent speed" and "actual speed".

Leandros

 

[yogi]

Hi Wisp

The Sagnac effect is based upon a different kind of experiment than MMx - in actuality, you can get the same difference c+v and c-v w/o considering rotation or curvature - its simply a consequence of the fact that the source/receiver has moved during the transit time - for example consider two mirrors A and B spaced apart a constant distance L with a source/receiver midway inbetween - then if the source/receiver is in motion toward mirror A and away from mirror B, the time required for a signal sent by the source to be returned from A will be less than the time required for the signal to be returned from the receding mirror B. In other words, you are really measuring your velocity wrt the two mirrors, not wrt the ether. In contrast, in MMx, the entire apparatus moves so the distance between the source and the reflecting mirror remains constant.

 

[clj4]

Hi Wisp

The Sagnac effect is based upon a different kind of experiment than MMx - in actuality, you can get the same difference c+v and c-v w/o considering rotation or curvature - its simply a consequence of the fact that the source/receiver has moved during the transit time - for example consider two mirrors A and B spaced apart a constant distance L with a source/receiver midway inbetween - then if the source/receiver is in motion toward mirror A and away from mirror B, the time required for a signal sent by the source to be returned from A will be less than the time required for the signal to be returned from the receding mirror B. In other words, you are really measuring your velocity wrt the two mirrors, not wrt the ether. In contrast, in MMx, the entire apparatus moves so the distance between the source and the reflecting mirror remains constant.

"Wisp" knows all this, he's been told this numerous times, by numerous people on different forums. It will lead nowhere since he's one of those people obsessed with
"proving relativity wrong". We are all wasting our time trying to explain to him the scientific truth, he'll never accept it.

Relativity has to be "wrong" in order for his personal theory,also called "wisp" (see his website) to be right.