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Feb2313 08:40 AM
ZapperZ

1 
37,474 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
37,211 
The notion of parallelism between a vector and a covector comes up naturally in the following context. Say you have a...

Dec1713 09:14 AM
stevendaryl

9 
502 
Hi all,
I'm sure that things similar to this have been covered before. Also, I'm sure that a Minkowski diagram...

Dec1713 08:45 AM
ScottTracy

11 
707 
I recently posted another thread on the General Physics sub forum, but didn't get as much feedback as I was hoping...

Dec1713 03:39 AM
Bill_K

4 
528 
Is there a single equation that can model both spacial and temporal metric contraction simultaneously? And also what's...

Dec1613 04:31 PM
berkeman

30 
585 
Our current version of the Schwarzschild metric is
d\tau^2=(1r_s/r)dt^2(1r_s/r)^{1}dr^2r^2d\Omega^2
where c...

Dec1613 09:54 AM
stevendaryl

99 
5,848 
Hello,
I have the Perimeter Institute Activity Package on Special Relativity and I am working through the problems...

Dec1513 07:53 PM
Simon Bridge

9 
783 
Hi
I have buyed the book Spacetime physics  Introduction to Special Relativity; Second Edition.
It is a great...

Dec1513 01:45 PM
jtbell

1 
832 
If you could create a small space on earth in which a person could fit that was totally unaffected by gravity, or that...

Dec1513 12:35 PM
Vanadium 50

14 
729 
In linearized gravity we can one sets
$$(1) \ \ g_{\mu \nu} = \eta_{\mu \nu} + h_{\mu \nu}$$
where h is taken...

Dec1413 10:35 AM
Bill_K

2 
515 
Am I correct in my understanding that two objects moving away from each other movee away from each other at the speed...

Dec1413 10:13 AM
Naty1

3 
578 
As I understand it, the value of a 4vector x in another reference frame (x') with the same orientation can be derived...

Dec1313 07:06 AM
Bill_K

6 
700 
I am studying relativity by myself. There is one problem in the book which says that the 4dot product of the...

Dec1313 04:31 AM
vanhees71

3 
781 
Hi All,
I studied about Michelson Morley experiment in my graduation in the compulsory Physics paper. I had...

Dec1313 03:14 AM
TumblingDice

25 
1,374 
in relativity theory, in a certain "rapid space" the distance between two neighboring points is given by
ds=√...

Dec1213 11:49 PM
nafizamin

6 
606 
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 
1,284 
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 
455 
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 
938 
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 
3,208 
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 
524 
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 
463 
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 
566 
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 
1,226 
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 
586 
Gentlemen
What does the stressenergy tensor describe?
The tt term of the stressenergy tensor expresses energy...

Dec813 08:09 PM
Simon Bridge

13 
974 
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 
914 
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 
1,513 
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 
986 
In various other threads we have been kicking around various equations for a spherical shell and discussing the...

Dec713 10:39 PM
PeterDonis

7 
820 
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 
397 
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 
1,247 
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 
588 
hi people!
please can any one explain me the conclusions of a thought experiment given below ?
consider yourself...

Dec613 09:18 PM
PeterDonis

8 
950 
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 
625 
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 
640 
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 
1,738 
Please view the following...
http://www.wimp.com/visualizegravity/
This is the way scientists try to explain the...

Dec413 09:48 PM
dauto

2 
684 
The Lorentz group generators, in any representation, satisfy the commutation relation
= i \left( g^{\nu...

Dec413 05:16 PM
spookyfish

7 
852 
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 
920 
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 
460 
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 
932 