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Feb2313 08:40 AM
ZapperZ

1 
41,327 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
40,956 
Does putting the concept of acceleration in SR make it equivalent to GR?
I see a lot of sources (including many...

Dec2012 11:53 AM
PeterDonis

49 
3,553 
hi!
thank you for all answers in this topic in previous threatin same topic. i open this new
thread in same topic...

Dec2012 06:25 AM
DaleSpam

6 
784 
While explaining how science works in my biology class my biology teacher said that relativity had been proved wrong,...

Dec1912 03:19 PM
PeterDonis

9 
1,009 
Is it enough to see the covariance of the wave equation the fourthvector potential (\phi, \bar{A}) satisfy? I mean,...

Dec1912 02:38 PM
PeterDonis

3 
541 
Dear Friends
Is there any coordinate tetrad in spacetime except Cartesian basis ?
since tetrad basis should be...

Dec1912 02:26 PM
Worldline

2 
763 
hi
can inertial reference frame be in different sizes at least in theory? i mean that can there be two different...

Dec1912 02:03 PM
George Jones

29 
1,636 
Hi All,
I think that I understand (as far as you can!) the ideas behind explaining why two twins have different...

Dec1912 09:55 AM
ghwellsjr

7 
1,159 
EDIT: Problem solved, the object would approach escape velocity (11km/s).
I'm sorry this was a bad question.

Dec1812 04:45 PM
pervect

3 
615 
Trying to put aside, somehow, questions of body elasticity,
How long does it take on average for a body, in outer...

Dec1812 08:59 AM
PeterDonis

21 
1,947 
Hi guys! I have a small doubt in the concept of age of our universe.Everyone say that our universe is 14.4 billion...

Dec1812 08:14 AM
Lino

11 
1,024 
I just want to make sure that the following assumption is equivaent to the first postulate.
Consider two inertial...

Dec1812 05:21 AM
metalrose

29 
2,678 
I have often thought about how the oneway speed of light can be measured without having to use synchronized clocks,...

Dec1812 04:02 AM
Jorrie

49 
4,178 
If I travel toward a star 100 ly distance (measured when at "rest") at a low % of c, the star will continue to appear...

Dec1812 03:35 AM
jartsa

24 
3,075 
I am trying to understand what exactly general covariance states. As I understand general covariance appeared as...

Dec1812 01:52 AM
haushofer

98 
8,604 
I would like to get a mathematically precise formulation of the EhlersGerenSachs theorem. I have heard that this...

Dec1712 06:00 PM
bcrowell

1 
523 
Would light at 10nm be traveling at a slower speed due to having to go a shorter distance than light at 1mm? The IR...

Dec1712 02:24 PM
nitsuj

2 
591 
According to the Schwarzchild metric an interval of proper time d\tau at a fixed distance r from an object of mass M...

Dec1712 01:58 AM
pervect

3 
708 
Say we were given an expression for the energymomentum tensor (also assuming a perfect fluid), without getting into...

Dec1712 01:20 AM
PAllen

24 
1,850 
I thought the speed of light was constant independent of the motions of the observer and light source. So I don't...

Dec1612 08:35 PM
k!rl

4 
743 
Can someone help me with understanding and explaining the Special theory of relativity.
I know the basics (time...

Dec1612 07:29 PM
DaleSpam

135 
9,915 
Hello! I was wondering if anyone knew of any good references (texts or whatever) to learn about the Thomas Precession....

Dec1612 04:13 PM
pervect

3 
796 
How is the speed of light, and path of travel, effected in timespace distorted (by say, gravity)?
We know that the...

Dec1612 11:41 AM
San K

2 
762 
Suppose there is a nuclear bomb orbiting around the earth at speed close to c. Some Bad Guy tries to set off the bomb...

Dec1612 08:00 AM
DaleSpam

12 
922 
Why is it that when describing time dilation, we say that the object (the thing observed) slows down relative to the...

Dec1612 06:04 AM
ghwellsjr

20 
1,582 
I wonder if there's a connection and it's a requirement or it's a completely different matter and space(time) warps...

Dec1512 09:16 PM
bcrowell

9 
1,083 
I'm not sure if this post belongs with general physics or relativity, so feel free to move it. I am trying to get a...

Dec1512 07:27 PM
K^2

12 
1,383 
This may be a stupid question, but why can't the expansion/contraction of spacetime from a gravitational wave be used...

Dec1512 01:52 PM
dllahr

2 
690 
I enjoyed this video about tensors very much. I would recommend it to anyone seeking to understand the concept in...

Dec1512 11:19 AM
jmatt

1 
597 
Do photons obey the 1/r^2 gravity law?
This was a question that came up in our recent PhySoc meeting and noone...

Dec1512 07:01 AM
andrien

97 
6,595 
While simultaneity conventions for inertial frames in flat spacetime (SR) are noncontroversial, numerous questions,...

Dec1412 10:12 PM
PeterDonis

190 
17,115 
if you have 2 spaceships and they depart in exactly the opposite direction from a starting point, say a space station,...

Dec1412 07:57 PM
ZapperZ

56 
5,366 
The probelm is the following:
There is a uniform I current measure in a rectangular loop while this is moving in a...

Dec1412 02:51 PM
Ramapaa

0 
566 
Discussions involving Hawking radiation in the study of black holes usually require their preexistence; however, if we...

Dec1412 01:33 AM
atyy

36 
2,721 
Consider observer A at rest, seeing observer B traveling in a rocket at high speed towards a star C. Star C is at rest...

Dec1412 01:21 AM
Mike Holland

14 
1,455 
When we look at stars that are far away from earth, they appear to be still in the sky. However, these stars are...

Dec1412 12:36 AM
PAllen

2 
636 
Hi,
I was wondering if anyone could clarify something for me. I have been reading about the curvature of...

Dec1312 09:38 PM
darkthoughts

22 
3,313 
In a paper about field theory in curved spacetime, an author says that the Lagrangian density for a free scalar...

Dec1312 03:34 PM
elfmotat

3 
640 
In Einstein field equations,the term that is responsible for curving SpaceTime is the StressEnergy tensor.But we...

Dec1212 03:01 PM
pervect

8 
1,024 
I am just beginning graduate selfstudy of Special and General Relativity, so forgive me if my question seems niave. ...

Dec1212 01:20 PM
Meir Achuz

6 
1,136 
Our professor derived a Minkowski force like this:
F^\mu = \left
Does this mean that i can write 4force...

Dec1212 01:04 PM
Meir Achuz

4 
1,212 