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Feb2313 08:40 AM
ZapperZ

1 
42,414 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,061 
I'm not native English speaker so some words or phrases I say maysound strange and awkward but I hope you could get...

Dec1111 03:23 PM
Vanadium 50

5 
1,328 
Has anybody come up with a way to derive the LT not based on the constantcy of the speed of light in all inertial...

Dec1111 10:24 AM
harrylin

38 
6,052 
Hi,
I'm studying the general relativity with the book by Woodhouse, and I have a question about the past set in...

Dec1111 08:21 AM
rurouni_sohji

0 
868 
For instance at what speed would something have to be going relative to the Earth that only one day happens for this...

Dec1111 03:07 AM
ghwellsjr

6 
1,286 
I understand the equivalence of gravity and uniform linear acceleration. But I'm less clear on the example involving...

Dec1011 07:09 PM
A.T.

10 
3,065 
When I heard about the faster than light neutrinos, I began wondering about what changes that would make in physics. ...

Dec1011 06:53 PM
phinds

7 
1,729 
I was wondering if anyone could explain to me where the 2nd order terms in the gauge transformation
...

Dec1011 06:06 PM
torquil

1 
944 
I read this week in Schutz's description of PoundRebka experiment, which demonstrate that a photon also interacts...

Dec1011 01:56 PM
Passionflower

2 
1,422 
hi all
I was thinking abt the time dilation derivation thought experiment a flash of light shone on a mirror(imagine...

Dec1011 11:51 AM
Janus

6 
1,729 
Suppose you have the simplest type of black hole  time independent, no angular momentum or charge, Schwarzschild...

Dec911 06:53 PM
Elroch

17 
4,227 
Hello,
Surfing the web I came across a question posted by someone. Basically the question asked if I were to have a...

Dec911 05:23 PM
Passionflower

15 
1,782 
So the principle of equivalence states that any effects due to acceleration must also occur with gravity, as it's...

Dec911 07:39 AM
Fredrik

9 
2,175 
I have some questions about time dilation I not really understand to come further (and I find it all very...

Dec811 09:19 PM
digi99

8 
2,683 
The twin paradox seems not to be understand by everybody.
But if you see it like this (see below), everybody...

Dec811 07:52 PM
digi99

17 
2,191 
At an origin there is an observer (A) who fires a laser at a series of beacons in a straight line spaced 186,000 miles...

Dec811 05:45 PM
DaleSpam

12 
1,583 
I'm in an intro course and my shaky ability to solve differential equations is apparent.
How would you go about...

Dec811 05:34 PM
pervect

1 
1,917 
It says that x' = gamma (xvt)
Now what exactly does that formula mean?
I take it that x is a point in my...

Dec811 02:43 PM
ghwellsjr

8 
2,137 
Dear All,
My quest for an answer began a few days ago when I was at my mates house and we were watching a...

Dec811 12:49 PM
boogiewithstu

16 
2,024 
The stressenergy tensor is usually defined in standard GR treatments as
T_{\mu\nu} =...

Dec811 11:50 AM
ramparts

5 
2,200 
Hi all,
Let's say we can witness a star going inside a black hole. From our perspective the star will approach the...

Dec811 08:10 AM
Elroch

25 
3,867 
My professor asks, "Double check a formula that specifies how Riemann tensor is proportional to a curvature scalar."...

Dec811 04:38 AM
haushofer

2 
1,088 
Hi, I'm trying to reconcile some general relativity stuff and I'm getting confused on a few topics.
Would someone be...

Dec811 12:58 AM
PAllen

13 
2,623 
Please correct me where I'm wrong,
Our solar system is moving around our galaxy at 250km/s and CERN can accelerate a...

Dec711 09:07 PM
PAllen

6 
6,953 
I am having trouble understanding how special relativity reconciles the concept of causality. In one frame of...

Dec711 05:36 PM
Functor97

2 
1,208 
Hi I m new here. i hv been thinking,searching abt this but could get no where
If i m moving in a rocket away from...

Dec711 10:34 AM
ghwellsjr

1 
1,520 
I have been doing searches on the relativity of time and its relation to the "age of the universe," among other...

Dec711 08:03 AM
Elroch

5 
1,708 
From http://www.physicsforums.com/showthread.php?t=40391 in gravitational time dilation.
At the center of...

Dec711 04:30 AM
pervect

2 
1,251 
Leptons are supposed to be eternal because they do not decay. What about if you through a lepton (say electron in this...

Dec711 01:11 AM
tom.stoer

2 
1,186 
I have a few questions about time dilation due to gravity. It seems to me there are some strange/interesting...

Dec711 12:51 AM
PatrickPowers

30 
9,524 
Recently after taking differential equations, I started doing EM problems and have gained a "feel" for Maxwell's...

Dec611 02:25 PM
DuckAmuck

0 
880 
Obviously, infinite speeds would defeat time keeping.
Infinite speed would imply that a particle could be at the...

Dec611 11:32 AM
lalbatros

6 
1,288 
1 how to find that the universe is expanding from general theory of relativity
2 how to apply general theory of...

Dec611 10:13 AM
Naty1

7 
1,748 
Suppose, there are two inertial frame first is in motion with constant speed and second is motionless. We can say that...

Dec611 10:04 AM
Naty1

4 
1,380 
Is there any relationship between the Lie (\pounds) and covariant derivative (\nabla)?
Say I have 2 vector fields...

Dec611 09:01 AM
nickj1

9 
9,938 
So, I've never been able to understand where the extra mass comes from when an object is traveling near the speed of...

Dec511 08:48 PM
PAllen

19 
3,083 
Space time Geometry and GR, taken from lecture notes
http://www.mth.kcl.ac.uk/courses/cm334.html
...

Dec511 12:51 PM
atyy

1 
1,553 
I have read:
F=q(v*B)
where q=charge of the particle
v=velocity of the charge particle
...

Dec511 08:57 AM
jfy4

3 
1,337 
HI all
There is smth I dont understand in building initial data for BH
The equations everybody uses uses spacetime...

Dec511 08:53 AM
PeterDonis

11 
1,946 
In another thread here,
http://www.physicsforums.com/showthr...=548148&page=3,
post #36,
Peter Donis posted...

Dec511 07:45 AM
Naty1

5 
1,241 
Ok. I understand that the set of Lorentz boosts and space rotations is equivalent to the set of Lorentz...

Dec511 02:02 AM
Fredrik

4 
1,876 