All Questions
Tagged with speed-of-light special-relativity
1,419
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Is a photon truly massless? [duplicate]
First of all, I am not a physicist or mathematician, not even a hobbyist but the following statements have always puzzled me:
$E=mc^2$
A photon is a desecrated particle of energy.
A photon is ...
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1
answer
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Physical meaning of $vx/c^2$ in Lorentz transformation
In Lorentz transformation, this is the formula of time dilation
$$ t' = \gamma \left( t - \frac{vx}{c^2} \right) $$
It can be derivated from the formula of length contraction and be proved ...
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Black hole production via light speed [duplicate]
As a test particle with rest mass approaches $c$ relativistic mass increases to infinity, does this mean that the energy required to continue the acceleration will create a black hole (as time also ...
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Second postulate of Special Relativity - Finite Invariante Speed?
@JohnRennie, the most decorated physics stack exchange user of all time, answered the question whether the first postulate of special relativity implies the second (Einstein's first postulate ...
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4
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The speed of light in vacuum (but which speed?)
Since there are several different definitions of speed describing light propagation like Group velocity, Front velocity and Phase velocity.
Which speed is meant when the phrase "The speed of ...
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Understanding the math of the Michelson-Morley experiment
I'm having some conceptual misunderstandings of the Michelson-Morley experiment. The time for the beam going perpendicular ($t_{across}$) of the aether wind I am getting:
$$(ct)^{2}=d^{2}+(vt)^{2}\\
(...
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3
answers
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Why is the speed limit of special relativity $C$ equal to the speed of light $c$ and why must there be only one?
DISCLAIMER: this question is different from other questions posted here previously despite accidentally similar titles. This question is not a duplicate of the one linked bc the linked question is ...
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3
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Is a Lorentz transformation allowing an infinite value $c$ still a proper Lorentz transformation?
Is it correct to say that inertial systems are related by Lorentz transformations even if we do not know if the "invariant speed" is finite or infinite? To me, this is incorrect because $c$ ...
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3
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What are relativistic particles? [duplicate]
What are relativistic particles? I got it in a question of mechanics.
So, what is it about a particle that makes it "relativistic"?
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Proof of the invariance of $c$ using the Lorentz group
Apologies if this question was already asked a few times but i could only find proofs of the invariance of $ ds^2 $.
Is there any way of proving the 2nd postulate (that $c$ is invariant in all ...
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Speed of light along $y$ and $z$ axes when there is relative motion
There are two coordinate systems. One is stationary and the other moves in the positive $x$-direction with a speed of $v$. I don't know how to interpret the $\sqrt{V^2 - v^2}$ term since light always ...
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Rindler coordinates and objects possibly exceeding the speed of light
Assume $c=1$
So I've been on a bit of a journey trying to derive special relativity by myself and in doing so was analyzing the viewpoint of a uniformly accelerating observer.
I was particularly ...
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3
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How Taylor series is compatible with special relativity?
In mathematics, an analytic function is defined by its possession of a Taylor series with a positive radius of convergence ($R_c>0$). Notably, certain analytic functions—such as holomorphic ...
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Does light accelerate? [duplicate]
If considering the general formula for acceleration, ie.
Δ V/ΔT, we would get zero as the velocity of light is constant and does not change.
However, what about when photons travel through different ...
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Could relativity be consistent if there are multiple light-like fields with different invariant speeds?
My understanding of real physical theory of electromagnetism goes like this:
The Maxwell equations can be used to derive the speed of light;
$$\nabla\cdot\textbf{E}=0$$
$$\nabla\cdot\textbf{B}=0$$
$$\...
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