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Feb2313 08:40 AM
ZapperZ

1 
40,472 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
40,129 
Hello everyone! My question is this: Do we believe time is a constant and forces such as gravity affect our perception...

T 01:27 PM
ghwellsjr

28 
1,123 
If velocity is relative and if we cannot say which is moving away from what *objectivley, how do we say that time...

T 12:20 PM
ghwellsjr

46 
969 
According to Einstein (e.g. in his book The Meaning of Relativity), a clock rotating about a central clock will be...

T 10:44 AM
Nugatory

18 
752 
As you may already know, given a timelike congruence describing some extended body with worldtube ##\mu## embedded...

T 09:30 AM
WannabeNewton

15 
1,488 
I was wondering why can't I use formulas from the "Special Relativity" in cases like:
F=mv^2/r Or F=qv•B...

T 12:56 AM
ghost313

2 
122 
Are there any EXACT solutions similar to Schwarzschild or Kerr in a spacetime which is not asymptotically flat; e.g....

Y 01:36 PM
George Jones

3 
298 
Hello everyone. I am attempting to teach myself about special relativity, and have learned a derivation for the...

Y 01:31 PM
toothpaste666

8 
338 
I got stuck in deriving the velocity of the particle from the acceleration equation. Here are the details of the...

Jul2014 10:07 PM
ecastro

6 
445 
Hello. I'm a layperson curious about physics.
I've read that Quantum Gravity could eliminate the predicted...

Jul2014 06:22 PM
sshai45

11 
655 
I have recently gone over the derivation of the stress energy momentum tensor elements for the special case of dust....

Jul2014 04:42 PM
spacetime

4 
338 
*Edit: I noticed I may have posted this question on the wrong forum... if this is the case, could you please move it...

Jul1914 10:23 AM
coleman123

8 
1,049 
its been years since I took a physics course so I might have what amounts to a really dumb question. However, I got...

Jul1914 10:21 AM
objecta99

19 
633 
Hi
I am a new(ish) student of general relativity. I am currently reading 'Relativitiy DeMystified'
However...

Jul1914 03:58 AM
Nugatory

1 
265 
Hi, I'm trying to derive the displacement of an object with proper acceleration (constant) α.
t is our laboratory...

Jul1814 06:45 PM
pervect

2 
341 
Hi
I am teaching myself GTR from Dirac's book...

Jul1814 04:00 PM
WannabeNewton

3 
326 
Starting at the beginning and have been having some difficulty explaining the implications of the constancy of the...

Jul1814 03:30 PM
etcota

3 
343 
So as the title says, what are the physical reasons behind requiring the connection between tangent vector spaces to...

Jul1814 10:53 AM
stevendaryl

27 
1,493 
Hello Everyone, I am new to this forum.
I understood from sources that spacetime is like a fabric. The massive...

Jul1814 07:48 AM
A.T.

16 
1,295 
What does spacetime curvature means?

Jul1814 05:03 AM
ChrisVer

13 
409 
Hi everyone, I just wanted to share this really cool game MIT Game Lab made, it's called A Slower Speed of Light:...

Jul1814 03:15 AM
A.T.

3 
682 
Assume observer is located on the surface of the earth with a small amount of time dialation due to gravity. There are...

Jul1714 11:21 PM
rcgldr

2 
354 
In "The Hidden Reality", Brian Greene mentions almost offhand that inside the event horizon of a black hole, space...

Jul1714 08:22 PM
PeterDonis

9 
1,040 
Is it possible to assume relativity is still basically correct and reject the btheory of time? Or does a coherent...

Jul1714 05:13 PM
Vanadium 50

2 
352 
Hello Forum,
An event is a point in spacetime with spatial coordinates and a time coordinate: (x,y,z,t). An event...

Jul1714 11:33 AM
fog37

7 
634 
Please excuse me for being a complete and utter pleb, my meager knowledge of Leonard Susskind's holographic principle...

Jul1614 04:59 PM
pervect

8 
870 
Suppose you have a differentiable manifold where at each point you have attached a set of basis vectors...

Jul1614 10:50 AM
George Jones

8 
747 
Hello everybody. I would like to kindly ask your help with a hypothetical hairy question about which I think a lot...

Jul1614 03:08 AM
Irigi

5 
605 
From what I understand the Piezoelectric effect occurs when there is a change in dipole moment. If a crystal was to be...

Jul1614 12:46 AM
KingBigness

0 
528 
I have pretty much learned how to derive the left side of Einstein's field equations now (the Einstein tensor that...

Jul1514 06:21 PM
pervect

7 
869 
Dear All,
I am trying to calculate the Riemann tensor for a 4D sphere. In D'inverno's book, I have this equation...

Jul1514 03:50 PM
MrR

25 
1,237 
Suppose we have a test mass located at some point above the earth. It is allowed to free fall down toward the earth. ...

Jul1514 02:12 PM
e2m2a

6 
602 
The variation of the Einstein Hilbert action is usually done in coordinate basis where there is a crucial divergence...

Jul1514 06:30 AM
center o bass

4 
979 
I am slowly learning more and more about physics, but one issue I've come across is understanding how gravity can have...

Jul1514 04:47 AM
Chronos

10 
1,139 
The example given is as follows : we have 3 space ships(numbered from left to right) placed in space moving at...

Jul1514 01:37 AM
ghwellsjr

7 
832 
Hi, I am new here, I am no physicist and I'll admit have not read much on physics, but I do have a keen interest and a...

Jul1414 05:15 PM
pervect

26 
2,006 
hy,
there is nothing in Maxwells equations that would limit the speed of light.
the only way one can get light...

Jul1414 07:20 AM
PhilDSP

46 
5,902 
I've gone though a lot of google searches and couldn't find the reason why one way speed of light is undefined.
All i...

Jul1314 01:09 PM
TumblingDice

8 
1,014 
Hi all. It is well known that in Schwarzschild spacetime, a torquefree gyroscope in circular orbit at any...

Jul1314 12:54 PM
PeterDonis

5 
1,144 
Dear all,
As I was reading my book. It said that the line element of a particular coordinate system (spherical) in...

Jul1214 06:12 PM
MrR

9 
866 
Greetings,
I have been reading William Baylis  "Electrodynamics  A Modern Geometric approach". For anyone who has...

Jul1214 02:56 PM
HJ Farnsworth

0 
697 