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Feb2313 08:40 AM
ZapperZ

1 
41,634 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
41,284 
I know that magnetism can be explained as the relativistic interaction between say a current, and a moving charge. My...

Dec2213 04:32 PM
Bill_K

9 
891 
What little I've read about Einstein, out of a textbook, regarded his theories on motion at the speed of light. I'm...

Dec2113 07:02 PM
Simon Bridge

69 
2,415 
Schwarzschild solution for Planetary Motion:
##g_{ij}= \left( \begin{array}{cccc}
\frac{1}{(1(\frac{2*m}{r}))}...

Dec2113 02:35 PM
DaleSpam

1 
420 
I would like some information concerning GR and the dimensional contraction of a standard rod due to gravity. As the...

Dec2013 06:18 PM
PeterDonis

6 
731 
So in special relativity we have ds'^{2}=ds^2, which is another way of saying \Lambda^{T}\eta\Lambda=\eta. Where...

Dec2013 08:11 AM
PeterDonis

22 
937 
Hey Guys!
I've got an exciting question! It's been burning on my mind for years, but I think I can formulate it...

Dec1913 06:46 PM
Simon Bridge

7 
900 
Hi guys. I have something stuck in my head since a few days and I'd like to have your opinion about that. I don't know...

Dec1913 03:50 PM
tartaneto

9 
910 
This is in response to the closed thread "perspective on Relativity and length contraction"
The Loedel drawing is a...

Dec1913 11:09 AM
phyti

0 
512 
Hello All,
I like to think that I have a decent background in physics and related material, but I confuse myself...

Dec1913 05:51 AM
DaleSpam

200 
8,473 
Hello everyone!
There is a postulate of special relativity that says that the speed of light in vacuum is the same...

Dec1913 12:58 AM
ViolentCorpse

15 
937 
Traveling on a spaceship to Alpha Centauri A, 4.37 light years away, at a velocity of 0.92 c,
if you just calculate...

Dec1713 04:30 PM
tinytim

6 
735 
Hi,
Does somebody know a link where the Einstein tensor is fully written out, i.e. only containing the metric and...

Dec1713 02:05 PM
bapowell

3 
521 
PLEASE NOTE: When replaying these animations, click on the circular arrow in the bottom left corner of the video...

Dec1713 01:14 PM
Histspec

5 
1,776 
Well, relativity says whatever moves, it's volume shrinks and mass increases (as observed).
So if i am traveling at...

Dec1713 09:20 AM
ZapperZ

4 
647 
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 
608 
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 
833 
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 
679 
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 
781 
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 
11,412 
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 
866 
Hi
I have buyed the book Spacetime physics  Introduction to Special Relativity; Second Edition.
It is a great...

Dec1513 01:45 PM
jtbell

1 
1,000 
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 
886 
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 
566 
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 
652 
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 
820 
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 
891 
Hi All,
I studied about Michelson Morley experiment in my graduation in the compulsory Physics paper. I had...

Dec1313 03:14 AM
TumblingDice

25 
1,582 
in relativity theory, in a certain "rapid space" the distance between two neighboring points is given by
ds=√...

Dec1213 11:49 PM
nafizamin

6 
727 
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 
1,590 
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 
545 
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 
1,046 
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 
3,861 
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 
568 
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 
529 
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 
669 
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 
1,563 
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 
625 
Gentlemen
What does the stressenergy tensor describe?
The tt term of the stressenergy tensor expresses energy...

Dec813 08:09 PM
Simon Bridge

13 
1,054 
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 
1,122 
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 
2,088 