The speed of light is fundamental universal constant that marks the maximum speed at which information can propagate. Its value is $299792458\frac{\mathrm{m}}{\mathrm{s}}$.

learn more… | top users | synonyms

1
vote
3answers
123 views

Detecting absolute motion inside a box

This is not a contradiction and I know it is impossible but still consider a thought experiment by me and point out if something is wrong. See the following picture and then the explanation follows. ...
2
votes
2answers
106 views

What will be the relative speed of a photon in a light ray to another photon of opposite direction light ray?

If two light rays start simultaneously in the space from exactly opposite ends in opposite direction that is separated by a distance of 600000 km in a way they meet at the mid point (300000 km from ...
0
votes
2answers
109 views

Speed of light that is traveling away from the observer

The second postulate of Special Relativity states: The speed of light in a vacuum is the same for all observers, regardless of their motion relative to the source. Now imagine the observer ...
-2
votes
2answers
121 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
180 views

Disk spinning at the speed of light

Of course, I mean that the edge of the disk is traveling at the speed of light. This is a question that popped into my head a few years ago when I was learning about some basic relativity in high ...
1
vote
1answer
31 views

About accelerating particles

Can a particle moving below the speed of light be accelerated more and more until it is travelling at c? IF so does it behave like electro-magnetic radiation?
1
vote
1answer
86 views

Is there a connection between exclusion principle and the speed of light?

As far as I know exotic stars are composed of degenerate matter created by the balance between gravity and pressure of exclusion principle and as the mass of the star grows it goes into more ...
1
vote
1answer
35 views

Resultant wave in the Michelson-Morley experiment

I was wondering when the two waves in the experiment, don't they lead to constructive interference? Consider the first case in the image. The two combining waves should lead to constructive ...
1
vote
1answer
122 views

Speed of approach between image and object

A plane mirror image approaches the object at the same rate the object approaches the mirror. So the speed of approach is twice the speed at which the object approaches the mirror. If the object ...
0
votes
1answer
101 views

A vertical variation of modern versions of Michelson-Morley

For almost a year now, I have been in the uncomfortable position of having an idea. However, there is one nice thing about this idea. It makes a concrete, exact and relatively easy to test physical ...
-2
votes
1answer
162 views

Resolution of the EPR paradox using relativity of simultaneity

A simple explanation for photon entanglement experiments Example: Quantum teleportation La Palma-Teneriffa in 2012 (distance 143 km) - Photons were entangled in such a way that when measuring ...
2
votes
0answers
57 views

About the speed of light

If Mr. E is aboard a spaceship traveling near the speed of light the usual reason for the spaceship not going faster than $c$ is the (relativistic) mass of the ship increases without bound, I think. ...
2
votes
0answers
83 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
85 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 ...
2
votes
0answers
478 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 ...
1
vote
0answers
38 views

twin paradox inferring cosmic speed limit

As I understand it, the twin paradox was integral to Einstein's conclusion that nothing can travel faster than the speed of light. Why wasn't there a similar conclusion for a hypothetical scenario ...
1
vote
0answers
117 views

Is false vacuum bubble nucleation possible in our universe?

Is it possible that a false vacuum bubble to nucleate into our universe rather than a true vacuum one ? If yes,it will expand at speed of light within our spacetime or what ?
0
votes
0answers
37 views

Why plane em waves are basic?

Why are plane EM waves required in the derivation for the speed of EM waves in term of absolute permeability and permittivity? I can't understand how to calculate flux for electric field passing ...
0
votes
0answers
92 views

Theoretically if you passed the speed of light, would there be a sonic boom equivalent?

I know that it is technically impossible to reach the speed of light since the mass of the object traveling would reach infinity. Despite this if it were possible, would there be some sort of ...
0
votes
0answers
38 views

How to apply equations to figure out how Hubble's constant affects the speed of light?

For my thought experiment, I will create my very own infinite expanding universe similar to our own assuming current cosmological theories are correct, except for a couple things: $$\text{(Hubble's ...
0
votes
0answers
117 views

Do photons feel gravity of approaching objects only?

I have read that photons while travelling near massive objects such as the sun experience gravitational pull which is why we see some stars at different positions than they are when seen towards the ...
0
votes
0answers
69 views

does light beam bend when moving with a constant velocity?

I'm studding special relativity and there is a famous example where there is a moving train witch has a light source on its floor and a mirror attached to its roof. an observer in the train sees a ...
0
votes
0answers
115 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
95 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 ...