All Questions
Tagged with refraction speed-of-light
23
questions with no upvoted or accepted answers
5
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1
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How is light trajectory affected by the trajectory of environment it passes through?
There's a sci-fi concept of slow light that I find very amazing:
Imagine a glass material that has index of refraction $n$ say, $3,000,000,000$ which means:
$$v_{glass} = \frac{c_{vacuum}}{n} = 0....
- 3,107
4
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0
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Does the intensity of blackbody radiation depend on the speed of light in the medium?
In 1863, in “ON THE CONCENTRATION OF RAYS OF HEAT AND LIGHT, AND ON THE LIMITS OF ITS ACTION”, Clausius wrote in the conclusion:
To harmonize the effects of ordinary radiation, without concentration, ...
- 1,225
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What is the upper bound for the index of refraction of space?
It seems that gravitational waves and gamma waves travail at about the same speed, arriving within seconds of each other over distances in the ranges of $10^6$LY. Naively, I would assume this caps the ...
- 1,269
3
votes
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Photons when passing through matter
I am wondering whether there is a simple—or complicated—way to explain from a purely quantum mechanics (or QFT) viewpoint what happens to the photons when they go through some material whose index of ...
3
votes
1
answer
206
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Why is refractive index equals to speed of light upon phase velocity and not group velocity?
We have been using group velocity for most purposes as its the velocity with which the wave packet travels, they why do we use phase velocity for calculating refractive index.
2
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0
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Why does refractive index increase with concentration of the medium?
I learnt that lights decrease velocity in a medium during absorbance and emission of its energy in the charged particles in the medium. From the Beer's law, I read that absorbance is directly ...
- 21
2
votes
2
answers
101
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How do we know that light cannot travel faster than it does?
We assume the speed of light in vacuum is its maximum speed but can we not assume that it could be faster, or slower?
- 21
2
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0
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774
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What happens when light is reflected from a surface moving in a medium with a huge refractive index?
Imagine a mirror is moving away from a light source in a substance through which the speed of light is very slow -- so slow that the speed of the mirror is close to being the same as the speed of the ...
- 163
1
vote
1
answer
94
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When light passes from one medium to another. Depending on the density, it would experience a change in velocity. Why would its vector change as well?
For example, when light passes through water its velocity decreases and refraction occurs. Why? Why is there a change in direction. If I slow down a car I don’t suddenly turn left.
1
vote
0
answers
24
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Is it possible to calculate speed of light in a mixture of A and B, by knowing the speed of light in both medium A and B seperately?
So we all know speed of light varies in different medium, which then makes me thinking is it possible for us to calculate the speed of light in a thoroughly mixed medium consists of X% of medium A and ...
- 639
1
vote
1
answer
64
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Frequency of EM waves
When light travels in air, all the component frequencies of light travels with the same velocity $v_{air} = 1/\sqrt {\epsilon_0\mu_0}$ (where $\epsilon_0$ is independent of frequency. Then we say that ...
- 453
1
vote
0
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Modeling curved light in media with "complex" indices of refraction
I've written an algorithm to solve the Time Difference of Arrival (TDoA) localization problem, using Bancroft's method (see). Given the coordinates of $n$ nodes in ...
- 799
1
vote
0
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54
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In anisotropic media, is there a speed of light tensor like there is a refractive index tensor?
Lets say we have an homogeneous anisotropic medium where $\tilde\mu_r=\tilde\epsilon_r$ so we don't have to worry about polarization effecting anything. As such, the refractive index can be simply ...
- 780
1
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0
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23
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Is it possible to simulate a high index of refraction
I am trying to demonstrate the effect of index of refraction on light speed to a high school class. As with all adolescents, if a story does not have extreme impact, it does not register (hence the ...
- 1,721
1
vote
1
answer
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Can the Dirac Hamiltonian accommodate a variable speed of light?
The Dirac Hamiltonian has the form1
$$\left[\beta m c^2+c\sum_{n=1}^3\alpha_np_n\right]$$
where $\alpha_n$ and $\beta$ are Hermitian matrices, and $c$ is the speed of light.
My question: Is there a ...
- 411