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Feb2313 08:40 AM
ZapperZ

1 
37,382 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
37,141 
Do wormholes really exist in spacetime?
I mean, as a race we need to colonize the rest of the galaxy before too long...

Feb608 10:15 PM
Aftermarth

5 
1,893 
Hi again. I just reread the paper from 1920 where Einstein ponders "ether". Based on General Relativity he seemed to...

Feb608 08:22 PM
country boy

1 
1,379 
SR can be used to describe E&M in a local inertial frame, can anyone tell me a book or paper, that describes E&M in a...

Feb508 10:26 PM
Phymath

3 
1,199 
http://upload.wikimedia.org/wikipedia/commons/1/1d/Eventhorizonparticle.svg
Would there still be a t axis? ...

Feb508 02:37 PM
EnumaElish

6 
2,440 
First I'm not a native English speaker so sorry for grammar errors .
Ok lets start my hobby is to learn things and...

Feb508 09:36 AM
mrzero

2 
2,059 
Hello everyone,
Perhaps it has been asked many times in the past, so please forgive me, and I appreciate your...

Feb408 01:55 PM
pervect

4 
1,736 
When I was in my late teens I read a book called the "The Dancing Wu Li Masters" by Gary Zukav, (those prepared to...

Feb408 09:33 AM
Ich

4 
1,422 
I have a question,why is time and space inseperable,that is,why can't one exist without the other?
Oh and I have...

Feb308 05:57 PM
Shaun Culver

23 
2,467 
What is the accepted view of spacetime?
Do we think we really live in a fourdimensional spacetime, or is it...

Feb308 02:28 PM
marcus

2 
1,444 
Could it be that an observed object moving back in time is indistinguishable from an object moving forward in time? To...

Feb308 08:10 AM
DaleSpam

16 
3,403 
I've heard that if the speed of light were to change there would be no effect on the universe because changing it...

Feb208 06:41 PM
rbj

22 
3,106 
Hi everyone,
If anyone could point me in the right direction with this problem I'd really appreciate it.
"Show...

Feb108 11:10 PM
Dick

2 
2,111 
Just a thought...
Pick a spot/location on the surface of the Earth.
Now, the Earth is rotating on its axis and...

Feb108 06:30 PM
yuiop

6 
2,344 
Are there any differences between a Lorentz scalar quantity or a Lorentz invariant quantity?
That sound be stupid but...

Feb108 04:25 PM
Llewlyn

3 
2,197 
I read elsewhere that when one travels in a spaceship "very close to the speed of light" that objects behind the ship...

Feb108 03:12 PM
yuiop

12 
1,709 
Hi,
I'm looking for a mathematical formulation of galilean spacetime, i.e. the "essence" of galilean spacetime in...

Feb108 01:51 PM
dx

0 
1,044 
Why were there many good G.R. books published in such a short space of time around '72'73? Is there a reason?

Feb108 09:51 AM
Shaun Culver

0 
1,136 
Okay, I don't know really if this is the right forum to ask this in, so I apologize if it ain't. I will also add that...

Feb108 08:54 AM
yuiop

8 
1,531 
At what scale does time dilation manifest itself?
Is time dilation dictated only by the velocity of entire large...

Feb108 02:59 AM
pervect

2 
1,085 
Photon can be emitted by an electron's changing of its orbit. As we know. photon always travels at speed c, never...

Feb108 02:48 AM
pervect

16 
2,641 
What is the physics answer to the question of why light has an invariant speed
to anyone and everyone, other than...

Feb108 02:29 AM
pervect

117 
32,911 
A warning is often given that if one wants to have a spaceship travelling at relativistic speeds (usually to get to...

Feb108 02:25 AM
pervect

1 
1,542 
We all know magnetic fields can be blocked by metal, light can be blocked by
nontransparent materials, forces...

Jan3108 11:41 PM
mdeng

16 
3,746 
When tachyons became all the rage, why was the automatic assumption made that, because they seemed to travel faster...

Jan3108 11:06 PM
JesseM

21 
4,367 
You know the 'thoughtexperiment'....the spacehip travelling at a speed close to the speed of light....where a photon...

Jan3108 02:52 PM
JesseM

17 
2,485 
I understand that a photon has never been known to decay. Is this because, travelling at the speed they do, time has...

Jan3108 07:14 AM
lightarrow

32 
5,755 
I haven't seen the twin problem configured this way before. But it seems to me it should lay to rest the argument that...

Jan3108 03:06 AM
yogi

7 
1,398 
Hey folks,
I see a lot of papers where an action is conformally transformed into the Einstein frame.
Can...

Jan3008 10:00 PM
robousy

0 
1,565 
does anyone know where to freely download the essays, published in Annals of Physics, written by Einstein himself...

Jan3008 09:55 AM
1effect

1 
1,846 
I was wondering if anyone had an explicit form of the hamiltonjacobi equations for GR.
I had a little attempt myself...

Jan2908 11:16 PM
shoehorn

1 
1,641 
this isn't my explanation, but I was just wondering what others thought:
"Einstein's special theory of relativity...

Jan2908 10:01 PM
JesseM

2 
2,508 
Einstien gives the example of an observer riding on the rim of a spinning disc. Using his length contracted rulers he...

Jan2908 07:38 PM
pervect

7 
2,397 
A.A.Logunov, M.A.Mestvirishvili, Yu.V.Chugreev
THE EQUIVALENCE PRINCIPLE...

Jan2908 01:52 AM
J.F.

0 
1,590 
Can somebody please help me with this question?
Obviously when we observe an event it has not occured at the time...

Jan2808 11:53 PM
yogi

7 
4,614 
I have read many NASA history series books on early space missions and none of them mention time dilation. In fact...

Jan2808 05:51 PM
gonegahgah

33 
7,281 
hi
I read a few other post about this but i'm an engineer, not a physicist, not a genius and didn't get much wiser....

Jan2808 03:03 PM
Doc Al

80 
45,915 
What exactly are "preferred coordinates"? Or a "preferred coordinate system"?

Jan2808 01:48 PM
jcsd

9 
2,122 
obviously the equations of tidal forces and geodesic deviation are very similar to lead one to motivate yourself to...

Jan2708 08:17 PM
smallphi

3 
1,519 
Hi
I am just wondering if E = mc^2 then wouldn't it also be correct to say 1/2mv^2=mc^2 since E is kinetic energy....

Jan2708 07:06 AM
Seek45

5 
2,666 
Hi all,
I am very new to this forum so please let me know if I have posted this in the wrong place, and thanks in...

Jan2708 03:17 AM
JesseM

2 
1,379 