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Feb2313 08:40 AM
ZapperZ

1 
37,356 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
37,122 
in relativity theory, in a certain "rapid space" the distance between two neighboring points is given by
ds=√...

Dec1213 11:49 PM
nafizamin

6 
595 
I'm debating whether this should go in the GR & SR section, but anyways, I heard both claims and both of them are...

Dec1213 04:46 PM
Bill_K

18 
1,277 
This question has been asked two years ago, but it wasn't resolved (I think). Here goes
This problem is Problem 5...

Dec1213 03:09 PM
Bill_K

1 
449 
Hi, I've taken a course in SR and studied GR on my own, but I do not know how to solve problems of this type. This is...

Dec1113 05:46 PM
tom.stoer

10 
932 
Hi,
As is well known, Relativity claims that a rod of a given proper length will appear length contracted when...

Dec1013 07:34 PM
pervect

67 
3,177 
What is the defining moment when you use relativistic equations instead of classical ones? I have heard something as...

Dec1013 01:41 AM
Blackthorn

3 
520 
The approach taken in linearized gravity seems to be to 'perturb' the 'Minkowski metric' such that
$$g_{\mu \nu} =...

Dec913 07:00 PM
WannabeNewton

1 
456 
Hi,
I know these questions must sound ridiculous and I apologize, I'm a newbie. My textbook says that the inner...

Dec913 01:27 PM
sciencegem

3 
560 
Huffingtonpost ran a story heaping praise on a guy for demonstrating GR with the old "rubber sheet" analogy. This demo...

Dec913 12:15 PM
WannabeNewton

18 
1,206 
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 
582 
Gentlemen
What does the stressenergy tensor describe?
The tt term of the stressenergy tensor expresses energy...

Dec813 08:09 PM
Simon Bridge

13 
968 
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 
902 
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 
1,497 
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 
970 
In various other threads we have been kicking around various equations for a spherical shell and discussing the...

Dec713 10:39 PM
PeterDonis

7 
810 
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 
391 
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 
1,240 
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 
582 
hi people!
please can any one explain me the conclusions of a thought experiment given below ?
consider yourself...

Dec613 09:18 PM
PeterDonis

8 
946 
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 
617 
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 
637 
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 
1,710 
Please view the following...
http://www.wimp.com/visualizegravity/
This is the way scientists try to explain the...

Dec413 09:48 PM
dauto

2 
680 
The Lorentz group generators, in any representation, satisfy the commutation relation
= i \left( g^{\nu...

Dec413 05:16 PM
spookyfish

7 
844 
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 
916 
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 
451 
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 
925 
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 
672 
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 
476 
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 
474 
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 
1,450 
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 
3,022 
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 
2,436 
Hi, GR permits wormholes hypothetically right? But surely they should violate conservation of energy
because if one...

Dec113 08:03 PM
WannabeNewton

1 
498 
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 
850 
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 
441 
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 
556 
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 
496 
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 
396 
My understanding is that an outside observer sees objects undergo time dilation as they approach sources of gravity,...

Nov3013 10:25 AM
WannabeNewton

10 
710 