All Questions
Tagged with refraction special-relativity
16
questions
16
votes
2
answers
2k
views
What happens if light/particles exceeded the speed of light for a particular medium?
While the speed of light in vacuum is a universal constant ($c$), the speed at which light propagates in other materials/mediums may be less than $c$. This is obviously suggested by the fact that ...
- 1,187
12
votes
2
answers
5k
views
Deriving the law of reflection for a moving mirror in relativity
I am following a training course and came across this proof, from my colleague, that the ordinary law of reflection $\theta_i = \theta_r$ does not hold in relativity:
Let $S$ be a perfectly ...
- 2,547
2
votes
2
answers
2k
views
What do physicists mean when they say "speed of light"?
Does it make sense to say, "The speed of light varies?" Some may say right off the bat "Yes, it changes as a wave passes through a different medium." However, I'd like to say no, because when I hear ...
- 495
0
votes
1
answer
174
views
Do quasiphotons have mass?
If I understand correctly, per special relativity, anything that travels at a speed of $c$ must be massless and conversely, anything massless must travel at precisely $c$ in akl reference frame. We ...
- 2,327
41
votes
5
answers
13k
views
Is light actually faster than what our present measurements tell us?
It is well established that the light speed in a perfect vacuum is roughly $3\times 10^8 \:\rm m/s$. But it is also known that outer space is not a perfect vacuum, but a hard vacuum. So, is the speed ...
user182521
3
votes
3
answers
702
views
Does the speed of light in different mediums affect the Lorentz transformation?
We know that the Lorentz transformation is derived using the speed of light in a vacuum. But if we were to use it in water, would it change since the speed of light in water should also remain ...
- 2,479
-1
votes
2
answers
739
views
Does the speed of light have a range of speeds due to medium-dependency?
An EM particle-wave propagates in a vacuum at a constant speed $c$, independent of the source/receiver but dependent on most mediums it moves through. Since the vacuum is a medium, and if logically ...
- 31
6
votes
2
answers
3k
views
Refractive index of dielectric in different frames of reference
The setup
A transparent isotropic dielectric medium moving in the negative $x'$ direction at speed $v$ in frame $S'$ is stationary in frame $S$, where it has refractive index $n$. In other words, ...
- 6,425
5
votes
5
answers
2k
views
How is it possible for the wavelength of light to change in a medium?
So my physics class has just finished a long unit on optics while at the same time I've been trying to teach myself relativity. I admit my understanding is probably rudimentary, but I figured all the ...
- 51
4
votes
1
answer
594
views
Theoretically if you passed the speed of light in a medium, would there be a sonic boom equivalent?
I know that it is technically impossible to reach the speed of light in vacuum since the mass of the object travelling would reach infinity. However in a medium, would there be some sort of ...
- 151
4
votes
3
answers
5k
views
How can the speed of light change in the medium when we know that it is always equal to $c$? [duplicate]
How can the speed of light change in the medium when we know that it is always equal to $c$? If we say the speed of light is changing in the medium, it will contradict the Einstein's law of special ...
3
votes
5
answers
1k
views
Is there a medium less dense than vacuum, in which light can travel faster than $c$? [closed]
Is there a medium less dense than vacuum, in which light can travel faster than $c$? If not, can we make it?
- 659
2
votes
3
answers
669
views
Refraction and reflection in special relativity
I know that special relativity postulates that the speed of light is the same no matter the inertial reference system. Consider that we have a medium with absolute refractive index $n$ ( when the ...
1
vote
1
answer
149
views
How does a refractive index of less than one not violate relativity?
If I am not mistaken, this video says that X-rays travel faster in glass than in a vacuum. Special Relativity says that information can not travel faster than the speed of light in a vacuum, so what ...
0
votes
1
answer
89
views
Would forcing a photon to travel under $c$ even after it leaves a medium break Relativity? [duplicate]
So, I stumbled onto this article which really blew my mind (http://www.bbc.com/news/uk-scotland-glasgow-west-30944584). To sum it up, these researchers set up some kind of material that slowed a ...
- 1,666