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Feb2313 08:40 AM
ZapperZ

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42,480 
The section of the Usenet Physics FAQ titled "Experimental Basis of Special Relativity" has been cited here many...

Dec3107 02:06 AM
jtbell

0 
42,138 
Are these really just two ways of explaining the same thing?

Dec2711 02:25 PM
nitsuj

7 
1,608 
I thought it would be interesting to show how light moves in a Coke bottle:
fSqFWcb4rE&hd
Is the speed of light...

Dec2711 01:20 PM
Doc Al

2 
1,026 
Consider a rod of length 1 m and I are in frame S. Now i move at a velocity considerable to velocity of light wrt S. I...

Dec2711 10:21 AM
Naty1

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1,624 
Why does the stationary observer see the spaceship light clock traverse a longer distance?
How can you prove this?...

Dec2611 07:38 PM
Snip3r

4 
1,065 
If FTL was true, shouldn't SETI start searching patterns also in neutrino bursts, and not scan as they do now, only...

Dec2611 12:22 PM
DaleSpam

2 
1,163 
i need someone to explain me the aberration of light , i tried to read i from my book its a bit more complicated than...

Dec2611 08:09 AM
Bill_K

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1,700 
Hello there!
Sorry for the dumb question, but for years I have been very curious and confused about this: I just...

Dec2611 07:34 AM
Dmytry

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2,650 
This is a thought experiment but not very academic.
Assume a satellite solar panel was critically designed in such...

Dec2511 10:53 PM
DaleSpam

4 
1,164 
Hello, has anyone attempted to write a program to generate an embedding diagram from a given metric or know how to do...

Dec2511 03:53 PM
theobserver

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822 
Inside a blackhole singularily, the center is pulling spacetime to it, but because the spacetime fabric inside and...

Dec2411 10:39 PM
Drakkith

15 
2,271 
This is a question about something in Sean Carrol's Spacetime and Geometry text. I'll quote here:
" ... current...

Dec2411 08:17 PM
bcrowell

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986 
I read in a book that since the area of a black hole increases, the entropy increases, so black holes are consistent...

Dec2411 06:47 PM
AuraCrystal

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1,218 
Maybe an old topic.
But if you reflect a light wave, and if the light wave is not coming back in exact the same...

Dec2411 12:53 PM
PAllen

15 
2,130 
My friend tried to tell me that the effects of gravity are instantaneous and I assured him that he was wrong because...

Dec2411 11:37 AM
TrickyDicky

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3,362 
What does mean KaluzaKlein particle? How can I imagine this? Can KaluzaKlein particle create KlauzaKlein Field?

Dec2411 06:20 AM
Thaakisfox

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1,430 
Awhile back A.T. & PeterDonis helped me through several basic confusions on my way to an intuitive understanding of...

Dec2311 12:35 PM
PeterDonis

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1,538 
My physics background is sparseI only know classical mechanics and E&M, and I have a selftaught (and therefore...

Dec2311 11:54 AM
bcrowell

2 
1,621 
Hi, I am currently struggling with an exercise in Sean Caroll's Spacetime and geometry. The question is "Can we make...

Dec2311 09:54 AM
IRobot

0 
982 
Does a photon "know" how fast to leave its emitter, which is moving relative to the photon's receiver, so as to be...

Dec2211 08:24 PM
Qzit

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4,266 
In SR. Anything FTL or superluminal can affect causality because there would be some frame where things move backward...

Dec2211 04:30 PM
PeterDonis

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28,277 
What exactly comprises a relative velocity in special relativity? I find it confusing when distant galaxies can be...

Dec2211 04:28 PM
DaleSpam

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1,896 
Consider i m moving at a velocity considerable to the speed of light. Above me there is a mirror stretching to...

Dec2211 04:04 PM
DaleSpam

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1,470 
Isham wrote:
http://arxiv.org/PS_cache/grqc/pdf/9310/9310031v1.pdf
When we come to a Diff(M)invariant theory...

Dec2211 10:51 AM
exponent137

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2,087 
Let's say there are two synchronized clocks on Earth.
One leaves the Earth going at .8c and travels in uniform...

Dec2211 05:38 AM
harrylin

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3,183 
The Schwarzschild solution to the EFE has the (possibly not physical) 'two sided' view (aka wormhole). Anyone know...

Dec2111 09:13 PM
knobsturner

6 
2,427 
I'm trying to understand the Schwarzschild solution concept of proper distance. Given the proper distance equation
...

Dec2111 05:33 PM
Passionflower

4 
1,676 
Can anyone explain in words (or equations if you can't use words, or in words to describe the equations) how...

Dec2111 12:24 PM
pervect

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4,148 
If mass really increases with speed then if 2 rockets leave earth, travelling parallel and close together, at close to...

Dec2111 11:48 AM
PeterDonis

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12,028 
It is proved in this topic (last answer):
http://www.physicsforums.com/showthread.php?t=536987

Dec2111 11:47 AM
digi99

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6,328 
Okay...
SO... According to the implications of Alcubierre's peerreviewed, published theory... According to his...

Dec2111 07:06 AM
ZapperZ

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1,108 
Are there any experimantal evidences which imply that antimatter interacts gravitationally
in exactly the same way as...

Dec2111 04:21 AM
StephenC

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4,582 
Assuming it were possible, how would you go about it? Lightspeed spaceship? Wormhole? Superman gravitational reversal?

Dec2011 05:38 PM
bm0p700f

3 
1,494 
What I mean is are there things traveling so fast in outer space that we don't exist in their FoR?
Or we haven't...

Dec2011 05:19 AM
Elroch

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1,902 
Theres something I don't understand.
Assume we have two light particles that approach each other. (obviously with...

Dec2011 03:25 AM
harrylin

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1,420 
Okay, here's a different idea for "propellantless" propulsion:
http://adsabs.harvard.edu/abs/2004AIPC..699.1138M
...

Dec1911 10:49 AM
AcesHigh

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9,306 
in many research of kaluza klein theory to unified electromagnetic & gravity fields these research begin with 5D...

Dec1911 10:08 AM
Mentz114

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925 
I have been doing some research on gravity, and I am having a very hard time with the following example I found in a...

Dec1911 09:14 AM
Messenger

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1,564 
I'm still having trouble with the basic foundations of relativity so I am taking a look here at the Galilean...

Dec1911 02:02 AM
elfmotat

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4,370 
Consider an absolute point somewhere in one of the universes and consider our light signal with constant speed C which...

Dec1811 10:13 PM
my_wan

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2,440 
It is wellknown that associated with the Kerr solution which represents a rotating black hole, there can be a region...

Dec1811 07:27 AM
Elroch

6 
1,596 