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Feb2313 08:40 AM
ZapperZ

1 
42,485 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,141 
Hi people,
I have the following question:
First, here is a concise statement of the major neutrino speed...

Dec913 05:51 AM
Vanadium 50

6 
649 
Gentlemen
What does the stressenergy tensor describe?
The tt term of the stressenergy tensor expresses energy...

Dec813 08:09 PM
Simon Bridge

13 
1,068 
How do we know a "photon" is massless?
Do we have any experimental proof?
Photon has momentum, it even bends in...

Dec813 01:04 PM
PeterDonis

10 
1,190 
I suspect this is somewhat off the beaten track here, but there may be some few that could give it a go.
Einstein...

Dec813 05:24 AM
K^2

18 
2,149 
Hi guys,
I am reading griffiths electrodynamics. I have a question. How does Maxwell equation suggest that the...

Dec813 02:22 AM
Rena Cray

9 
1,245 
In various other threads we have been kicking around various equations for a spherical shell and discussing the...

Dec713 10:39 PM
PeterDonis

7 
991 
Hello Everyone,
I came here with a question and hope you can shed some light.
We know that Ricci tensor which...

Dec713 10:15 PM
vaibhavtewari

4 
464 
Hi,
In classical and quantum physics and even in special relativity, shifting the energy of a system by a constant...

Dec713 10:44 AM
George Jones

28 
1,494 
I know about the MichaelsonMorley expt. trying to measure the speed of light, once in the direction of motion of the...

Dec713 01:25 AM
ghwellsjr

2 
651 
hi people!
please can any one explain me the conclusions of a thought experiment given below ?
consider yourself...

Dec613 09:18 PM
PeterDonis

8 
1,117 
Question in the subject.
I have no idea what the DoD's interest is in this. Sorry is this is the wrong forum.

Dec613 10:30 AM
TomServo

7 
713 
Would there be a direct proof of the energystress tensor of general relativity? My lecturer only provides me with a...

Dec513 10:23 PM
WannabeNewton

8 
794 
Consider two iron rods of about 10 metres separated by 10 metre. They are in series position and not connected in...

Dec513 07:40 AM
DaleSpam

39 
2,017 
Please view the following...
http://www.wimp.com/visualizegravity/
This is the way scientists try to explain the...

Dec413 09:48 PM
dauto

2 
787 
The Lorentz group generators, in any representation, satisfy the commutation relation
= i \left( g^{\nu...

Dec413 05:16 PM
spookyfish

7 
1,020 
Hello there! I have a more or less silly and possibly obvious question that's been bugging me a lot. Here's the...

Dec413 02:54 PM
George Jones

8 
1,087 
Hi,
Is it pure coincidence that if you put ##c=v_e=\sqrt{2GM/R}## in the escape velocity, you end up with the...

Dec413 02:11 AM
dvf

2 
681 
Hi all, think this might be a silly or trivial question but I've got myself in a bother so thought I'd get some help....

Dec313 02:59 PM
WannabeNewton

16 
1,052 
For example let's say i have two rods of same length ie. 4metres placed in a series position. They are separated by a...

Dec313 09:11 AM
PeterDonis

11 
886 
There is any field in General Relativity(I know gravitational field but it is not that which I mean)
Thanks

Dec313 09:09 AM
WannabeNewton

2 
538 
Hello all,
I have a geodesic equation from extremizing the action which is second order. I am curious as to what...

Dec213 02:29 PM
Bill_K

7 
578 
First of all, Happy Thanksgiving to you all! Now, my question:
I'm on earth viewing through a telescope. I...

Dec213 10:09 AM
ghwellsjr

44 
1,608 
Most of the paradoxes are solved by either "Relativity of simultaneity" or "Born rigidity"
And there is a 3rd tool...

Dec213 06:07 AM
AndrzejK

60 
3,471 
Hi, I'm new posting to these forums, so I'm not sure if this is in the right place. Anyway, here it goes:
I've...

Dec113 11:57 PM
yogi

40 
2,693 
Hi, GR permits wormholes hypothetically right? But surely they should violate conservation of energy
because if one...

Dec113 08:03 PM
WannabeNewton

1 
576 
I'm very noob at this and am a bit confused:
Formula 1: E_T = \gamma \cdot m c^2
Formula 2: p = \gamma m v...

Dec113 05:41 PM
PAllen

9 
993 
We have three observers. The A is in earth,B is into a car that runs with big speed,C is out of galaxy.
All...

Dec113 03:18 PM
Nugatory

7 
490 
I had always thought that length contraction meant that the object itself shrunk but I stumbled across an article...

Dec113 01:47 PM
Superposed_Cat

8 
647 
hi there,
In this Ex ( see attached snapshot ), point b), the poisson bracket equation is not so straightforward to...

Nov3013 12:25 PM
WannabeNewton

9 
544 
I mean the application,such as because of the time dilation, humans can observe some particles which don't have long...

Nov3013 10:47 AM
phinds

2 
437 
My understanding is that an outside observer sees objects undergo time dilation as they approach sources of gravity,...

Nov3013 10:25 AM
WannabeNewton

10 
781 
Hello,
Can someone please help me to understand equation (10) from this article http://arxiv.org/abs/grqc/0607020....

Nov3013 08:02 AM
Bill_K

1 
612 
The invariant mass of special relativity:
m_0{^2} = E^2 – p^2
There doesn't seem to be any quantity with units...

Nov2813 09:45 PM
Rena Cray

18 
1,657 
Well, I'm totally in a mess now

Nov2813 02:01 PM
dauto

4 
422 
The problem has been shown in the picture. Because of relativity, both the guys on the ground and on the vehicle would...

Nov2813 09:25 AM
Mentz114

9 
890 
Hi all. Hoping someone can give me a brief explanation re: a problem I'm having in trying to understand SR. Not...

Nov2813 06:31 AM
DaleSpam

55 
4,418 
Does the curvature of spacetime have a unit?

Nov2813 01:46 AM
Rena Cray

10 
679 
Consider a perfectly spherical dust shell with a large internal cavity. Imagine there is a moment when the dust is...

Nov2713 10:44 PM
PeterDonis

14 
756 
We know that the mass of any body turns to zero as it gains the velocity of light.
From Einstein's MassEnergy...

Nov2713 04:35 PM
PAllen

5 
647 
I've managed to confuse myself and don't understand the difference between the formula for Lorentz time transformation...

Nov2713 11:48 AM
yuiop

3 
562 