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Feb2313 08:40 AM
ZapperZ

1 
42,286 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
41,917 
Does this actually happen in outer space? Do things actually move in uniform motion relative to each other?
How...

Dec1811 03:07 AM
PeterDonis

7 
2,734 
When accelerating an electron through a PD of 10^3, that will give a momentum of 1 MeV/c right? Or is there something...

Dec1711 07:32 PM
Stickybees

4 
1,125 
Imagine a perfectly reflecting box with a homogenous distribution of photons within it with total energy E (not...

Dec1711 05:31 PM
pervect

1 
1,115 
After doing some playing around with area lights in raytracing, I realized that the shape of the emitter has a lot to...

Dec1711 05:22 PM
Elroch

3 
2,587 
I wanted to double check my calculations an interpretation of relativity. Thanks in advance.
Two identical ships...

Dec1711 03:39 PM
Fredrik

3 
1,295 
Good morning.
I would like to prove that the integral
h^{\mu \nu} (\vec{r},t) = \int d \zeta \int d^3 \vec{y}...

Dec1711 02:03 PM
lalbatros

1 
1,204 
I wonder what the minimum safe distance would be for a black hole with mass of a couple of billion solar masses. With...

Dec1711 10:44 AM
Tracer

39 
6,412 
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 
1,381 
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 
7,907 
Post any thoughts or ideas here.

Dec1611 11:32 PM
yoron

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1,796 
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 
1,494 
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 
1,314 
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 
2,838 
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 
1,202 
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 
2,178 
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 
2,041 
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 
1,727 
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 
1,029 
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 
1,788 
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

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4,679 
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 
1,555 
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 
2,894 
I read in the book the elegant universe,that Einstein first saw riemannian geometry in accelerated motion and...

Dec1511 09:56 AM
MikeLizzi

4 
1,267 
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 
1,413 
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 
1,554 
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 
1,784 
Can you use any of these theories in daily life? Or how can you?

Dec1511 03:27 AM
michelcolman

25 
4,095 
*** 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 
948 
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 
1,802 
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

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2,911 
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

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10,517 
okay, i am totally confused (again). i ihave a general understanding that the higgs mechanism is the effect which...

Dec1411 06:00 PM
Drakkith

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4,332 
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 
1,125 
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 
1,483 
Can anyone please explain the difference between Newtonian and GR when used to describe gravity especially with...

Dec1411 07:23 AM
LaurieAG

7 
1,513 
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

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2,685 
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

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5,336 
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

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3,008 
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 
12,608 
If we assume:
E = mc^{2}
and for photons:
E = hv
Then we can derive an effective mass:

Dec1311 11:26 PM
Passionflower

2 
1,105 