The speed of light is fundamental universal constant that marks the maximum speed at which information can propagate. Its value is $299792458\frac{\mathrm{m}}{\mathrm{s}}$.
0
votes
2answers
61 views
Special Theory of relativity on electromagnetic waves
Since time slows down and length contracts, when we travel almost at speed of light, if the speed of light (or EM waves) remains same and the wavelength of light remains same, do we measure the ...
6
votes
1answer
188 views
drift velocity of electrons in a superconductor
is there a formula for the effective speed of electron currents inside superconductors?
The formula for normal conductors is:
$$ V = \frac{I}{nAq}$$
I wonder if there are any changes to this ...
0
votes
1answer
44 views
Wavefront emitted by bodies at traveling near the velocity of light
I studied that no body can travel with the velocity of light. But, assuming that when a body moves nearly velocity of light, will it obey length contraction law of Einstein or will it emit the same ...
-1
votes
1answer
72 views
Speed astronauts measure moving at the speed of light
Lets suppose a spaceship travels with v = 0.9c relative to the Earth. The time inside the spaceship would pass slower than on Earth. Would the astronauts measure a different speed (that means, a ...
-6
votes
1answer
195 views
Speed of light is not fixed?
In my research, I found that the speed of light is not fixed. IS it true?
Namely, We know that light refracts when the medium it travels through changes. Actually, light travels in the same medium ...
5
votes
0answers
151 views
How is it possible the speed of light is not constant?
I was reading this article recently, which summarizes a couple of new studies into the speed of light.
In one paper, Marcel Urban from the University of Paris-Sud, located in Orsay, France and his ...
2
votes
0answers
59 views
How does this paper relate to standard QED?
This paper proposes a microscopic mechanism for generating the values of $c, \epsilon_0, \mu_0$. They state that their vacuum is assumed to contain ephemeral (meaning existing within the limits of ...
2
votes
0answers
79 views
Question on “new CNGS/OPERA measurement of neutrino velocity” (hep-ex/1212.1276)
A "new measurement of the limit on muon neutrino velocity with respect to the speed of light " by the OPERA neutrino experiment in collaboration with CERN has become public recently, as preprint ...
1
vote
0answers
242 views
What happens with photon when it is slowed down substantially?
In a dispersive media light's velocity can change substantially. Imagine we can slow it down to near 0 what the wave would look like?
Frequency of light does not seem to change even at v=0 (at least ...
0
votes
0answers
103 views
About the theory of relativity
Why is speed of light constant in every non inertial frame of reference? Is there any theoretical explanation behind this postulate Since we cannot completely depend upon the experimental results?
0
votes
0answers
51 views
Determining Ether Drag - Aberration of Starlight
In order to determine the relative motion between the Earth and the ether (the medium through which light supposedly propagated. It has zero density and complete transparency), scientists used the ...
0
votes
0answers
35 views
Light Group Velocities
I was recently linked this page: Group Velocity
This was after enquiring about the delay of light propagation down a fibre. I come from a telecoms background so I wish to understand the delay for ...
