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

Dec3107 02:06 AM
jtbell

0 
37,214 
Before posting anything, please review the Physics Forums Global Guidelines.
If you are seeking help with a...

Feb2313 08:40 AM
ZapperZ

1 
37,478 
Hey I'm reading about relativity and I stumble across statements such as if a fourvector is timelike then it's always...

Jun112 12:59 PM
George Jones

8 
1,597 
Does anyone know where I can find a mathematical proof that the norm of any fourvector is Lorentz invaraint?

May904 04:50 PM
DW

1 
1,516 
Hi,
I recently completed a course on Electrodynamics, with a short introduction to special relativity (and E/B...

Apr1010 11:43 AM
utesfan100

4 
1,305 
In SR, Four velocity was the proper time derivative of a world line, do we have to take the covariant derivative...

Jul1512 09:37 PM
Chestermiller

16 
1,274 
if the magnitude of the four velocity vector is always c then it can be rewritten in polar form with 3 numbers giving...

Jul2911 10:01 PM
Chestermiller

2 
3,210 
Hello PF community!
I'm having trouble with what strikes me as an inconsistency within conservation of energy,...

Dec111 11:28 PM
n+1

4 
1,573 
I've searched all over the web to get an answer for this, to no avail. So I decided to ask this question here and I'm...

Apr2710 05:34 AM
nik21bigbang

10 
13,774 
If in some frame I define a geometrical object as having 3 space components, how do I then find the time component...

Nov509 07:02 PM
jason12345

3 
825 
I am trying to get a handle on fourvectors. I see that there is a thing called a fourpotential, a fourgradient, and...

Nov1706 10:36 AM
Daverz

4 
2,503 
The fourvelocity as defined for example here, is given by
U=\gamma(c,\bar{u})
but I get
...

Mar1312 08:08 AM
PAllen

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1,326 
In another thread Naty1 said:The Wikipedia pages on fourvectors and related concepts (fourvelocity, fourmomentum,...

Sep809 06:57 AM
Austin0

50 
5,704 
somebody know about this terms: "timelike, spacelike or lightlike"
they often are used in relativistic electrodynamic...

Sep505 06:55 AM
DrGreg

3 
1,291 
From Schutz's A First Course in General Relativity
"A particle of rest mass m moves with velocity v in the x...

Apr910 09:00 PM
schwarzschild

3 
946 
Hi,
In Fourier analysis, we can decompose a function into sine waves with different wavenumbers that travel at...

Oct2811 01:09 PM
Ben Niehoff

6 
1,940 
I'm a little confused by extra dimensions. People seem to say different things about the 'extra dimensions. Everyone...

Nov1913 11:40 AM
gabriel.dac

2 
489 
I have read speculations that
(1) the cosmic microwave background radiation has a fractal distribution (nonintegral...

Sep1209 09:55 AM
nomadreid

2 
1,090 
Suppose, a long object is at rest in S frame. There is A (On the long object) and B (Near the long object, on the...

Apr312 04:25 AM
harrylin

29 
2,580 
As far as I understand, a spaceship going around rotating black hole should gain additional acceleration due to frame...

Mar1213 06:27 PM
Bill_K

6 
727 
What is Frame Draggin, and Gravity Waves where did the idea of them come from in GR?

Oct2404 04:01 PM
Chronos

4 
1,290 
Hi,
I am interested in the issue of frame dragging used in a number of galactic rotation models. However, I wanted to...

Oct1712 05:42 AM
mysearch

8 
1,282 
Can frame dragging around a black hole induce closed timelike curves (CTC)?

Aug311 07:56 PM
Chalnoth

9 
1,739 
I'm trying to wrap my head around how rotational frame dragging affects the centrifugal force of a massive, rotating...

Jan2810 02:09 PM
PhilDSP

5 
2,143 
Is there a simple mathematical relation between the speed at which the Earth spins and the magnitude of the...

Aug2204 09:18 AM
pmb_phy

1 
1,444 
I just read in a popular magazine about the satellite to be launched in order to measure the frame dragging by a...

Dec1703 03:42 PM
selfAdjoint

5 
2,473 
News story this morning.
http://www.msnbc.msn.com/id/6290610/.
Effect detected by observing two satellites over a...

Oct2109 10:24 AM
peron

8 
2,241 
From MSNBC: GR confirmed again as gravity measurements reflect the predicted spacetime dragging effect caused by...

Oct2204 11:44 AM
Phobos

1 
1,036 
I had a question that I was hoping someone could answer for me.
If light passes next to a massive rotating object...

Oct2907 07:56 PM
cesiumfrog

3 
2,461 
Does light beam create linear frame fragging around it?
If answer is positive, can light become 'tired' going thru...

Feb2211 12:33 PM
Dmitry67

4 
967 
Objects smaller than black holes, by mass can still drag space along with their rotation. I picture this like a plate...

Nov2710 02:10 PM
Passionflower

3 
1,126 
What is the difference, if any, between frame fields and coordinate bases?

May307 12:17 PM
masudr

4 
3,211 
It seems clear that all inertial frames would agree that a frame was accelerating based on instantaneous (short...

Jul310 03:49 PM
djy

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1,484 
given a frame of reference s In General Relativity in wich you meassure an interval of space dx, could we have another...

Aug2504 06:36 PM
pervect

5 
1,786 
Let's consider flat 4D Minkowski spacetime. Is it possible to define (local) coordinate
system for any observer (its...

May1010 07:40 PM
starthaus

4 
747 
I've been giving some thought to the new scientist article about the equivalence principle.
What initially seems like...

Feb1413 07:18 AM
brenan

2 
467 
Let's suppose that I am the Captain at a space dock sitting in interstellar space. My crew decides to go on a trip in...

Dec3109 05:56 AM
HallsofIvy

1 
926 
I've been learning about 4velocity and all the "proper" 4vectors recently, and if I understand correctly, proper...

Mar611 12:35 PM
EricTheWizard

2 
1,937 
I heard that some kind of experiment on framedragging was in process (or is that finished?). What was the outcome?...

Aug106 02:31 PM
pervect

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1,500 
HI, I've been mulling over the derivation of the Lorentz factor gamma in my head for some time now & had worried about...

Jan1110 10:40 AM
yuiop

7 
1,496 
I've read about 'ergosphere' in wiki and surprised at the information presented that ergospheres around very fast...

Oct1510 12:39 AM
PAllen

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895 
Hello I am having problems in GR because I do not understand how observations frames work in this theory. I have a few...

Apr713 06:40 AM
Agerhell

8 
608 