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Feb2313 08:40 AM
ZapperZ

1 
37,501 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
37,235 
I've just read the FAQ about this and IMO it is "not even wrong" to say that energy conservation doesn't apply to...

Aug811 05:40 AM
TrickyDicky

59 
5,132 
Knowing that a photon can not be at rest, I was wondering what would happen supposing if we travel at the same...

Aug711 09:30 AM
ghwellsjr

6 
1,504 
hello,
lets say the there are two bodies that are moving at the same speed of 50% of the light speed and they both...

Aug711 08:17 AM
HallsofIvy

5 
1,387 
SR leans more toward direct observation rather than explanation, which is fine, mostly resulting from experiments with...

Aug611 10:43 PM
GrayGhost

12 
1,409 
In Schutz book, A First course in GR page.11 eq. 1.2
...

Aug611 03:43 PM
TrifidBlue

6 
1,086 
I remember reading an article that said essentially that the point of reference and the number of "space structures"...

Aug611 10:57 AM
NBagley119

9 
1,334 
what would Rabcd;e look like in terms of it's christoffels?
or Rab;c

Aug611 06:26 AM
dextercioby

11 
2,668 
When the an object is accelerated and when the velocity approaches the speed of light, its mass increases...

Aug511 03:37 PM
DrGreg

5 
974 
In a previous thread someone pointed me to DH's FAQ article on the Rest Frame of a Photon. In the article DH states,...

Aug511 11:40 AM
rede96

60 
4,346 
This is something that has always bugged me about relativity... I must be missing something....
Lets say you have a...

Aug511 08:05 AM
Doc Al

4 
1,120 
General relativity states that our universe is four dimensional curved space so time dimension is not separated from...

Aug511 05:12 AM
harrylin

45 
6,801 
I’ve been looking at the Wikipedia article on affine connections with a view to better
understanding the choice of...

Aug511 02:06 AM
Goldbeetle

8 
1,477 
Pairproduction is the event when a particle and antiparticle is created from a single photon. We don't see 2 or more...

Aug511 12:20 AM
kannank

17 
1,979 
Hi,
I just started reading "The Elegant Universe" as an introduction to physics. Up to this point I thought I...

Aug411 10:10 PM
DaveC426913

5 
934 
If photons emit gravitons, then where does this energy come from? It cant pull it from its kinetic energy or maybe it...

Aug411 09:14 PM
cragar

16 
3,438 
Most of what I've learned about Special Relativity is self taught using Google and Wikipedia because I'm still in high...

Aug411 11:41 AM
Fredrik

4 
1,633 
We all realize time dilates in a gravitational potential. Is there any evidence to suggest there is time dilation in...

Aug411 11:19 AM
H_A_Landman

23 
4,950 
I'm a relative newbie to relativity (no pun intended  I know you've heard that one too many times), as well as to...

Aug411 10:18 AM
PAllen

58 
3,736 
I'm trying to use the equations on this page and I have solved the following. Is it correct?
...

Aug411 03:54 AM
randombill

1 
1,594 
In order to explain the relativistic nature of magnetism, a book shows an example of linear procession of charges:...

Aug411 01:38 AM
cragar

1 
1,225 
On my blog, I am having a continuing discussion on special relativity with another person (we are both amatuers). We...

Aug311 09:38 PM
DaleSpam

83 
6,636 
Can frame dragging around a black hole induce closed timelike curves (CTC)?

Aug311 07:56 PM
Chalnoth

9 
1,740 
can twin paradox be solved,if no, what r the difficulties scientist face to solve it?? or is there a solution on it.

Aug311 01:17 PM
pervect

2 
939 
Who’s “spin” is in the EinsteinCartan theory? Source’s spin or the test particle’s spin?
I quantum mechanics, when...

Aug311 12:21 PM
tom.stoer

3 
1,228 
I have been trying to figure this one out for some time now. I have read much on the subject, but it seems to be dealt...

Aug211 10:20 PM
ccm.student

163 
34,808 
can you construct (or if yes, is it regularly done) a Hamiltonian in curved spacetime? If you took a system and moved...

Aug211 06:06 PM
dextercioby

2 
786 
when we move with light our time is slower and when we move against it then it's slower but what if we move at 99%C in...

Aug211 04:11 PM
harrylin

94 
9,059 
If maths tells us 1 * 1 = 1
and it takes a positive cell to repel a positive cell .....
could in theory a...

Aug211 11:36 AM
Vanadium 50

11 
1,356 
I do not understand if you accelerate a hydrogen atom to 90% the speed of light its mass is greatly increased. Are...

Aug211 11:03 AM
DaveC426913

8 
1,870 
I understand that matter and energy bend space time, yet i am curious as to the level at which it requires to bend it....

Aug211 10:57 AM
rationalist76

3 
1,694 
1) Is it always a given that the spacetime curvature will be flat in a region in which there is no mass?
2)...

Aug211 10:25 AM
Bill_K

4 
1,201 
a situation of twin paradox
one twin alice is moving with 99%C another john is at rest on earth
this means 1...

Aug211 09:18 AM
ghwellsjr

6 
1,038 
I was reading something about the Cartan (vierbein) formalism in GR, in wich the connection is allowed to have...

Aug211 09:03 AM
dextercioby

3 
975 
If a bacteria was travelling through space at the speed of light would the cells
divide at a constant or relative...

Aug111 11:20 PM
rationalist76

3 
1,011 
how is twin paradox resolved in case of no/zero acceleration/deceleration?
two twins one on earth and other on a...

Aug111 01:20 PM
D H

131 
10,118 
There is no clock that will measure time independently of movement. And conversely, nothing ever happens that does not...

Aug111 10:52 AM
time_nerd

104 
8,132 
I didn't know where to post this, but I figured since it has the word "relativity" in my question I would stick it...

Aug111 01:49 AM
ghwellsjr

16 
1,797 
Let us consider the cosmological metric:
{ds}^{2}{=}{dt}^{2}{}{}^{2}{}  (1)
For closed models k is...

Aug111 01:20 AM
Anamitra

1 
518 
In Newtonian physics, the centerofmass of a group of particles depends on the instantaneous positions of the...

Jul3111 02:47 PM
DrGreg

4 
1,132 
Relativistic momentum is a vector, just as nonrelativistic momentum is a vector, right? Part of the relativistic...

Jul3111 02:47 PM
jaketodd

7 
3,912 