Hubble's law is inconsistent with special relativity
I will use bold letters to denote vectors and ordinary font for scalars.
Hubble's law states that the velocity V of an astronomic object is a function of it's position relative to Earth:
V = HR ,
where R is the radius-vector (vector which points to the object).
If Earth is not the center of the universe, then the same relation should hold for every other possible refference point.
Let's say we have two stellar objects M1 and M2, whos radius-vectors are R1 and R2 and velocities are V1 and V2 respectfully.
Hubble's law states that V1=HR1 and V2 = HR2
For simplicity's sake, let's assume that M1 and M2 are moving in opposite directions away from Earth, and are the same distance away. So their velocities are directed along the same axis.
So, using projections on that axis, V1=HR1 and V2 = -HR1.
What is the velocity V of M2 in the refference frame of M1?
Relativistic formula for velocity transformation gives: V = (V1-V2)/(1+(V1V2/c^2))
Using values for V1 and V2 from Hubble's law, we get: V = 2HR/(1+R^2(H^2/c^2))
*If* Hubble's law was universal, then instead of that we should have V = 2HR
This means that Hubble's law is impossible in flat Minkovsky space-time.
Only general relativity models could have a chance to account for it, but so far no mathematically sound models have been presented. Friedmann - Lemaitre metric is only valid for empty or unifromly filled space, and we're dealing with a universe which has a lot of distinct objects.
True
Side Score: 3
|
 |
False: here's why
Side Score: 4
|
|
|
|
|
Well, you shouldn't be using a relativistic model formula in the first place. Using Hubble's law for superdistant objects could give you faster-than-light velocities. The speed-of-light barrier is respected only locally. Superluminal distant objects are fairly common with general relativity, but causality isn't violated because their light can never reach us. So wouldn't this disprove special relativity? Not really. Special Relativity doesn't necessarily discount Fast-than-light travel, it just states that superluminal bodies cannot interact with subluminal ones. If you have: M1----------Earth----------M2 If you want to switch the frame of reference you should be calculating from M1 to earth, and not M1 to M2. Because you've not only changed the frame of reference but also the distance. . . "But Geocentrists' professional references doing the 'Machian' calculation are simply generalizing the techniques I've outlined before - doing the computation in, say, a heliocentric frame, and then doing the conversion to the Earth frame - a trick that works identically for any other planet or any other location in the Universe! Therefore their claimed proof fails to demonstrate the Earth more preferred than any other frame! By relying on these references they are making MY point. They do not show that the location of Earth is in any way a preferred frame beyond Mr. Martin's own personal prejudice." ~W.T."Tom" Bridgman, Ph.D Physics Side: False: here's why
Well, you shouldn't be using a relativistic model formula in the first place. Really? The relativistic model is used to interpret astronomic data and it would be totally unscientific not to use it to investigate the resulting interpretation. You remind me of religious fanatics who only use certain psalms in certain situations. Using Hubble's law for superdistant objects could give you faster-than-light velocities. That is not such a big problem, because one could argue that there are no objects beyond a certain distance. At least that would not directly contradict special relativity. What you said is not totally irrelevant (for the first time in our discussions). Because, it means that if special relativity and Hubble's law are true, then Hubble's consant cannot be a constant in time, i.e. H = H(t). Which again discredits the "Big Bang" story, because if H changes in time, then it could be just fluctuating around 0, which means there is no reson to use the Big Bang hypothesis. Superluminal distant objects are fairly common with general relativity, but causality isn't violated because their light can never reach us. Wrong, the reason causation isn't violated is because they are superluminal only in our frame. At least according to general relativity. Special Relativity doesn't necessarily discount Fast-than-light travel, it just states that superluminal bodies cannot interact with subluminal ones. It states nothing of the sort. If you want to switch the frame of reference you should be calculating from M1 to earth, and not M1 to M2. Because you've not only changed the frame of reference but also the distance. I was swithcing frame of reference from Earth to M1, to check how an observer on M1 sees Hubble's law (for example, how he sees M2). And the result is very different from Hubble's law on Earth. The distance is irrelevant to relativistic velocity transform. Side: True
1
point
|
