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Feb2313 08:40 AM
ZapperZ

1 
42,384 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,026 
In special relativity we have the invariant spacetime interval ds2 = dx2  c2dt2. If we think about classical...

Jan1214 12:50 AM
AcidRainLiTE

4 
609 
In the case of swarms of particles, the stress energy tensor can be derived by considering the flow of energy and...

Jan1014 08:38 PM
samalkhaiat

5 
532 
How does potential energy fit into massenergy equivalence in SR? As with all forms of energy, a potential energy of...

Jan1014 08:23 PM
Meir Achuz

4 
668 
Hi,
I've read that the speed of light is consistent for all observers, no matter where they are. So, for instance,...

Jan1014 06:20 PM
AlfieD

18 
1,039 
Hey, I'm trying to understand gravitational time dilation, but can not find a good explanation for what R equals in...

Jan814 10:45 PM
pervect

7 
641 
I've never fully understood how anything can actually fall into a black hole without the black hole evaporating first....

Jan814 01:46 PM
PeterDonis

86 
4,702 
Can anyone help me with Ex 4.1 in MTW?
What is a 'generic' field? My expectation is that it would comprise an...

Jan814 12:31 PM
TerryW

7 
1,185 
This is something I have pondered for some while... it is so obvious that there must be an answer and is probably a...

Jan814 02:37 AM
A.T.

17 
981 
Hi guys,
Can anyone please help me to grasp a minor detail in the derivation of the BelinfanteRosenfeld version of...

Jan714 08:25 PM
Michael_1812

5 
577 
If we use only rest mass as the source of gravity, but use the rest of general relativity. What are the differences...

Jan714 02:40 PM
DaleSpam

29 
1,447 
I just wondered how I transform electromagnetic dipole moments.
For example assuming I have magnetic dipole moment μ...

Jan714 10:08 AM
kuecken

4 
396 
Hi, I recently came across the idea that relativity can play a role in the repulsive force of a charge outside of a...

Jan614 05:21 PM
Jimmy87

7 
736 
New Pulsar Will Put General Relativity to the Test
by Dr. Ken Croswell
Astronomers have discovered the first...

Jan614 10:52 AM
CygnusX1

0 
505 
In another current thread on the possible invariance of pressure, I mentioned:
What is the current consensus on...

Jan614 08:20 AM
yuiop

12 
1,110 
If a space ship were going 99%c, and inside that spaceship was another spaceship going 99%c, and so on and so on. I...

Jan614 02:15 AM
ilikescience94

11 
815 
HI : Consider a cylinder of length L and volume V that contains one mole of an ideal gas. The familiar ideal gas law...

Jan514 01:17 PM
yuiop

27 
1,396 
I was thinking the other day:confused: The faster a person goes, the sooner he get to his destination. There has to...

Jan514 11:19 AM
mfb

21 
1,115 
hi, who can help me with this article because in my university its not avaliable thanks
...

Jan514 10:55 AM
Meir Achuz

2 
443 
When students are first introduced to special relativity, the first thing they are taught is the derivation of the...

Jan414 10:07 PM
jtbell

5 
669 
Hi Guys,
Your previous insights on the thread regarding gravitational rod shortening along the radial axis really...

Jan414 10:02 PM
Pierre007080

4 
566 
I'm about to ask derivation of dilation time in terms of Special Relativity.
I saw explanations in Introduction to...

Jan414 09:27 AM
Doc Al

1 
390 
Hi Guys,
Is there a simple formula (like lorentz equations for SR) for rod shortening ALONG THE RADIAL (geodesic)...

Jan414 08:49 AM
DaleSpam

41 
4,938 
Hi everyone,
I don't fully understand what is the regular method to state and solve problems in GR when no handy...

Jan414 08:08 AM
PAllen

1 
483 
Hey guys. I have a question regarding exercise 6.5 in MTW ("Radar Distance Indicator"). The exercise asks the...

Jan414 01:12 AM
PeterDonis

12 
1,037 
Hi,
Suppose O’ is moving forward with respect to O at speed v. A light behind him is switched on at t’ and x’...

Jan414 12:58 AM
ghwellsjr

28 
1,555 
If an "Object A" spins at nearly "c", and this object also is moving at any given posible speed. What happen with an...

Jan314 08:31 PM
WannabeNewton

8 
566 
Hi,
In modern physics aether theories are obsolete, all inertial systems are equivalent. For rotational motion, the...

Jan314 07:12 PM
ZapperZ

80 
3,993 
I couldn't quite figure out how to describe it shortly hence the weird title.
I was wondering what it would "look"...

Jan314 03:15 PM
ghwellsjr

5 
606 
Hi
I am reading Stephan Hawking's Universe in the Nutshell and there I didnt understand this sentence
"This...

Jan314 07:56 AM
DaleSpam

41 
1,760 
Surely I am missing something, can you explain what?
If we shoot a gun while travelling on a train, the speed of...

Jan214 03:53 PM
DaleSpam

36 
1,798 
Does a photon, or any particle that travels at c, believe the universe to be 2 dimensional?

Jan214 12:11 PM
ZapperZ

9 
504 
Hi guys. The following question is related to exercise 3.7 from Rindler's SR/GR text:...

Jan214 10:29 AM
WannabeNewton

22 
1,386 
As you guys probably know, as an objects speed increases, so does its mass. I was wondering if a black hole could be...

Jan214 09:19 AM
ilikescience94

17 
776 
Good morning. I have calculated the components of the Ricci tensor for the Schwarzschild metric and they are all 0,...

Jan114 11:10 AM
CarlosLara

1 
552 
Does inertial motion (understood in the SR sense) exist in a curved spacetime?

Jan114 10:21 AM
TrickyDicky

17 
744 
I recently came across this paper http://arxiv.org/abs/physics/0504110v2 by Oas that is a semirant about how...

Dec3113 05:48 PM
pervect

10 
748 
I have recently been involved in a rather animated discussion on another forum on the subject of "weight". To make a...

Dec3113 05:35 PM
pervect

25 
2,645 
Many basic texts on relativity refer to the mass variation equation:
m= gamma mo
It seems that...

Dec3113 04:05 PM
DaleSpam

22 
1,140 
Hello,
Recently I've been researching how to add velocities in a relativistic way, very interesting stuff. But...

Dec3113 01:42 PM
phyti

17 
900 
Here's the best of my understanding of the official explanation of what happens when O' fall in a black hole.
...

Dec3113 09:37 AM
PeterDonis

4 
555 