
Before posting anything, please review the Physics Forums Global Guidelines.
If you are seeking help with a...

Feb2313 08:40 AM
ZapperZ

1 
41,403 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
41,037 
Does the temperature a body depend on its frame of reference?
Does the internal kinetic energy depend on frame of...

Dec1711 03:41 AM
pervect

2 
1,365 
In general relativity, gravity is modeled as a curvature in spacetime. So the earth moves in a 'straight' path in a...

Dec1711 12:49 AM
andrebourbaki

29 
7,814 
Post any thoughts or ideas here.

Dec1611 11:32 PM
yoron

17 
1,757 
I've been interested for a while in the nature of spacetime. It's been a long time since any body talked seriously...

Dec1611 11:26 PM
berkeman

2 
1,469 
In another thread I asked the question if my mass is comprised of "Higgs Mass" and "Kinetic mass".
Drakkith was...

Dec1611 02:02 PM
nitsuj

7 
1,290 
Something has been bothering me for quite some time and when you cannot figure it out yourself ask a higher power,...

Dec1611 10:25 AM
PAllen

8 
2,770 
sorry if this has been discussed before but I've not had much luck finding anything on the forum search. Basically I...

Dec1611 09:00 AM
Ryan_m_b

2 
1,187 
What are the equations from which all of GR can be derived? Obviously one of the equations is Einstein's Field...

Dec1611 08:18 AM
dcpo

4 
2,138 
I was listening to Feynman on spacetime and he challenged the audience to find a paradox in simultaneity over large...

Dec1611 04:41 AM
Vanadium 50

11 
1,984 
Last thread that I initiated was titled `Simultaneity is directional while Time Dilation is not', which presented a...

Dec1611 01:39 AM
universal_101

7 
1,617 
I like to try and derive little things by myself if I think it is manageable. One such thing is the addition of...

Dec1511 11:58 PM
nhmllr

4 
1,014 
Edit. I think the topic is misinformative and I dont know how to change it.
Hey
I have to translate this into...

Dec1511 09:50 PM
ghwellsjr

3 
1,737 
Please note that I do NOT want to discuss whether gravity is a force or the effect of spacetime curvature here. If...

Dec1511 09:00 PM
andrebourbaki

10 
4,631 
Just wondering if the two are fundamentally linked ?
If the universe is in the shape of a 3 sphere and if it's...

Dec1511 05:15 PM
AugustusM

2 
1,528 
Do you want to interpret this as a fallacy in relativity? I posted part of this example before. Which is: what if you...

Dec1511 10:37 AM
discountbrain

32 
2,843 
I read in the book the elegant universe,that Einstein first saw riemannian geometry in accelerated motion and...

Dec1511 09:56 AM
MikeLizzi

4 
1,235 
So what will it see it self as?? At rest or moving a velocity c? Either way it seems to be a contradiction, so does...

Dec1511 07:56 AM
sri sharan

4 
1,393 
One can use the Principle of Extremal Aging to calculate the path of a freely moving body (in an inertial frame not...

Dec1511 07:55 AM
pervect

7 
1,533 
Hawking and others suggest that it is a very special deal that macroscopic black holes lose quantum information, but I...

Dec1511 04:10 AM
Elroch

6 
1,753 
Can you use any of these theories in daily life? Or how can you?

Dec1511 03:27 AM
michelcolman

25 
4,005 
*** Please ignore. Just noticed my error !!! ***
Ok. Having been beaten senseless untill I can see how the maths...

Dec1511 02:50 AM
Mike Hobbs

0 
933 
I have seen PeterDonis state that predictions of GR are expressed as contracted tensors i.e. scalars. And they are...

Dec1511 01:28 AM
PeterDonis

1 
1,771 
with the newest discovery of biggest black holes in the universe, i suddenly had this weird thought: what if they're a...

Dec1411 09:06 PM
nitsuj

3 
2,760 
Or is this only true when I am viewing someone else's clock?
Why does time slow down the faster something travels?...

Dec1411 06:51 PM
PeterDonis

98 
10,289 
okay, i am totally confused (again). i ihave a general understanding that the higgs mechanism is the effect which...

Dec1411 06:00 PM
Drakkith

10 
4,257 
I have been studying up on special and general relativity lately :)
But still a few things aren't clear to me...

Dec1411 03:24 PM
pervect

1 
1,109 
I know that GR deals exclusively with tensors (at least, in every book I have), but how does the same concepts of...

Dec1411 09:16 AM
haushofer

2 
1,392 
Can anyone please explain the difference between Newtonian and GR when used to describe gravity especially with...

Dec1411 07:23 AM
LaurieAG

7 
1,495 
I try to get the gist of the Special and General theories of relativity for more than two years now. And I still don't...

Dec1411 07:12 AM
ZapperZ

28 
2,646 
OK, if anyone is so inclined, let's continue the discussion here, since I think we are distracting from the main...

Dec1411 06:43 AM
juanrga

62 
5,237 
I tried to find an answer to this here, but may have missed it.
There must be a flaw in my understanding here,...

Dec1411 06:31 AM
harrylin

6 
2,955 
Howdy,
Does light exert gravity? last i heard, eletromagnetic radiation doesn't have mass, and thus no gravity, yet...

Dec1411 02:50 AM
jtbell

49 
12,485 
If we assume:
E = mc^{2}
and for photons:
E = hv
Then we can derive an effective mass:

Dec1311 11:26 PM
Passionflower

2 
1,085 
This question about the twin paradox(twins A,B). I hope everyone knows the statement. I have read explanations for...

Dec1311 03:13 PM
mathman

2 
1,020 
According to some physicist and cosmologist observation the speed of light is not a constant depending on region of...

Dec1311 08:10 AM
Naty1

5 
1,494 
If you have a particle, and you know its rest mass is about 100 Mev/c^2 and in the lab frame you measure it to travel...

Dec1211 10:36 PM
kmarinas86

2 
1,162 
Suppose, A is moving with constant speed c/2 and B is stationary. A fires a beam in direction of his travel. A...

Dec1211 09:00 AM
ghwellsjr

9 
1,410 
Hello guys, so I have a problem. I am familiar with a fair bit of physics but I cannot seem to cross the gap between...

Dec1211 01:03 AM
lalbatros

6 
1,526 
Does anyone have any references in the literature that talk about interpreting forces as Christoffel symbols?
...

Dec1111 10:54 PM
atyy

10 
1,783 
I'm interested in wormholes but my knowledge of advanced physics and general relativity is lacking. I was wondering,...

Dec1111 10:11 PM
DaveC426913

3 
2,340 