relative rotation

[nm-8]

Hi!

I'm studying physics for quite some time, and some time ago a thought popped up in my head....:

 

In classical distance measurement (Einstein, 1905) a lightsignal is emitted, and the time delay "T" is measured, it takes to reflect at a distance "X".

 

Einstein said the observer has orientation with the starfield surrounding him. I'd like to ignore this assumption. So let's say it's dark and cloudy within a cosmic nebular. And an observer flying there wants to measure the distance to the (dark) spaceship next to him.

 

He send a lightsignal, and gets it back, after T. All fine.

But what if he recieves it from a different angle, than he emitted the lightsignal?

 

Is a rotation of the observer the only cause that leads to an open angle between emission and absorption? Remember, that in a moving frame, a double mirror reflecting light between the mirrors, also an angle (>0) appears... So can the observer be certain, that a simple Rotation of the observer took place?

(I'm talking about pointlike (quantum acting) lightsignals. nothing continouus... so the observer can't just differnetiate the signals...)

 

any suggestions? I know that's actually not a yes/no question, but did you ever hear of such thoughts? Are there papers on that subject ("relativity without starfield"), to learn more in that subject?

[swansont]

A rotation means an accelerating frame, so you could (in principle) tell if you had undergone a rotation.

[nm-8]

An accellerating frame means an "already made" measurement, to submit a frame (coordinate system). But I'm talking about the local process of building a frame.

where local means at the place of the observer

 

For example, you wont find a difference if the observer makes (or doesn't make) a whole revolution, while the signal (h) emitts, reflects at the starship, and get absorbed by the observer again.

or two revolutions, or three... he will always get the photon from the same angle, at the same time, hence can't differ...and will build the same coordinatespace, to react on.

so the rotation of the observer has different phenomena as they rotation of a frame...

isn't it?

[swansont]

I guess I'm not understanding the situation. You can tell if you are rotating by doing a measurement. But if you don't do that measurement, you can't tell.

 

It's like if you had a Foucalt pendulum but only checked it every 24/sin(lat) hours. It wouldn't show the rotation of the earth.

[nm-8]

exactly, same result on measurement with or without revolution. thats the point.

 

if pointlike quantized photons are used for the signal, you are somehow restricted to just use one photon at a time (cycle). an uncertainty would appear, if a second photon is used, before the first one is absorbed, the observer couldn't destinct the correlation of emitted and absorbed signals definitely.

case1=(e1-a1)+(e2-a2) or case2(e1-a2)+(e2-a1)

are two different equally possible/probable cases leading to four different "distance-measurement"-results...

[nm-8]

if pointlike quantized photons are used for the signal, you are somehow restricted to just use one photon at a time (cycle). an uncertainty would appear, if a second photon is used, before the first one is absorbed, the observer couldn't destinct the correlation of emitted and absorbed signals definitely.

case1=(e1-a1)+(e2-a2) or case2(e1-a2)+(e2-a1)

are two different equally possible/probable cases leading to four different "distance-measurement"-results...

 

So this is just in case, you send a second photon while the first still is on it's way... so trying to measure a rotation with more photons just leads from "rotation uncertainty" to "photon uncertainty" as shown above... still the uncertainty on rotation builds a whole set of energystates all leading to the same measurement. anybody heard about this before?