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Feb2313 08:40 AM
ZapperZ

1 
42,426 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,073 
How small a box can you confine a photon to before its mass is large enough to form a black hole?
I think you can...

May1208 11:17 PM
yuiop

2 
2,583 
Hi,
it's very interesting, that many parts of special relativity were developed before Einstein by Lorentz, Larmor...

May1208 01:01 PM
peter0302

10 
2,134 
Attached are some notes that I made regarding the relativistic Doppler effect. They are about 4 pages long, and gives...

May1208 11:47 AM
shalayka

0 
2,091 
Dear all,
Following is a problem, I suppose, is related to some controversy called "Dingle's Dilemma", as I read...

May1108 08:59 PM
DocZaius

57 
4,928 
Wiki
If speed susceptible to Doppler's effect. Why shouldn't field since we're so determine they have a speed?

May1108 10:12 AM
russ_watters

1 
808 
Hi I am interested in studying special and general relativity at a mathematically rigorous level, and I need to know...

May1008 04:11 PM
DavidWhitbeck

11 
3,289 
Hello !!!
i would like to know what i should know to move on to the general and special relativity regarding to...

May1008 11:21 AM
robphy

4 
954 
I am trying to clarify a number points regarding both redshift and blueshift in the context of relativity. Standard...

May1008 07:31 AM
mysearch

5 
1,921 
Ok guys,
Explain me this.
In twin paradox, one of two twins, paul and peter, when paul goes for a space ride at...

May1008 06:29 AM
MeJennifer

7 
1,552 
You hold in the palm of your hand a classical particle with momentum
P = (E,cp_{x},cp_{y}, cp_{up}) where cp_{up}=0...

May908 12:52 PM
DaleSpam

12 
1,390 
Does a photon curve spacetime, i.e., produce a gravitational field? Is the degree of curvature a function of its...

May908 08:41 AM
exponent137

38 
12,349 
When we derive equation of motion by variation of the action, we use rules of ordinary differentiation and...

May908 02:36 AM
arroy_0205

8 
2,530 
I just have a question relating to Mass Dilation;
Mass is defined (by the dictionary) as
Now, mass is a...

May808 06:58 PM
DaleSpam

3 
1,356 
Am I right in assuming that Gravity Probe B has proved that the rotation of the earth (@~465metres /sec.) 'swirls'...

May808 02:15 PM
Nickelodeon

2 
1,195 
I just posted about what is termed "apparent superluminal velocity of galaxies" and gave a website of an article...

May808 02:06 PM
RandallB

11 
3,515 
Well, let's say we put energy to spin every particle in an atom. Do spinning them faster have relativistic effects as...

May808 12:20 PM
pam

1 
1,312 
Place equal amounts of matter and anitmatter in a box on a scale. It's a very good box; it's very reflective, and...

May808 09:43 AM
pmb_phy

13 
2,195 
I know that the speed of light cannot be attained in vaccum as by the time of reaching there, mass increases...

May808 05:35 AM
Hootenanny

1 
1,255 
I am looking for an expression for the total energy of a particle of rest mass m_0 that includes kinetic and...

May708 07:54 PM
snoopies622

10 
1,506 
I took a course in special relativity as an undergrad, but am now almost 6 years removed from it and have not retained...

May708 03:56 PM
jtbell

6 
1,580 
Hi all,
I've been dusting off the grey matter a bit, and have a question regarding an example I found used in both...

May708 02:49 PM
sumofprimes

17 
6,045 
Hi!
I am studying special relativity and I still don't understand completely the relativity of time dilation:
each...

May708 02:22 PM
dude222

7 
1,910 
Is it plausable to take into account the speed of the earths spin when calculating tmie dilation for satellites and...

May708 01:31 PM
mogsy182

1 
1,177 
So is it the closer you are to the centre of a body the slower time will go? or is it the other way round. also why is...

May708 12:53 PM
shalayka

2 
1,006 
I got a master degree in physics and I still found that this is difficult to expalin Faraday's law of induction within...

May708 12:36 AM
dude222

3 
4,231 
I posted a simple thread regarding Lorentz transforms, but it has been locked for "staff review". May be because I...

May608 04:41 PM
mitesh9

20 
3,102 
My question is simple. I made a bet with my physic teacher. :cool:
I believe time can contract. When two bodies are...

May608 11:46 AM
DrGreg

29 
3,579 
Can anyone explain me what is physical significance of "Lorentz Transforms"?
That means, apart from the math, how...

May608 03:57 AM
Integral

18 
2,847 
Ok, I'm uneducated in physics and all I know is what I've learned from the internet and a single book "universe in a...

May508 10:49 PM
Chrisc

24 
3,357 
What is Aether supposed to be now days (and in Einstein's day)? Isn't Aether just space and time (and maybe their...

May508 10:06 PM
Ken G

37 
3,081 
Hi all
I wasnt sure where to place this thread. Im currently doing a project on GPS and have deceided to take the...

May508 11:37 AM
mogsy182

2 
924 
I was thinking about gravity when I thought that gravity only attracts.Why doesn't gravity repel?Do you think there is...

May408 04:47 PM
cristo

23 
4,981 
Foster and Nightingale give an equation for the proper time of a radially falling clock between any two distances....

May408 11:08 AM
Stoonroon

2 
2,050 
my question is if we define the quaternion
U= dtidxjdykdz
where i,j,k are the complex part of the...

May408 09:21 AM
mhill

0 
1,193 
I've read that the GPS system has to take into account the Sagnac effect when sending signals from the satellites to...

May308 07:53 PM
Stoonroon

15 
7,264 
hello people of physics,
i am a 14 year old boy from Greece and i am generaly attracted to...

May308 07:07 PM
jtbell

3 
1,102 
Measuring the relativistic mass and energy
When we speak about a physical quantity we should define it and it...

May308 07:03 PM
jtbell

7 
2,146 
In the view of PF posters, what is the "current" theory explaining the Sagnac effect? I have heard of something...

May308 06:51 PM
Stoonroon

2 
3,995 
Does gravity function as a lens, a prism or both?

May308 02:23 PM
jtbell

1 
1,420 
I understand photons have no rest mass, but I also learned in my physics class p=h/(lambda), and that mass depends on...

May208 08:20 PM
fireball3004

7 
1,542 