All Questions
Tagged with speed-of-light physical-constants
97
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What would happen if $c$ wasn't constant, but the quotient of $c$ with the scale factor $a(t)$ was? [closed]
I'm supposing there are strong reasons to disregard this scenario but I can't understand exactly what would it imply, and why it is not at all considered in cosmology. What I'm talking about is: we ...
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On the (variable?) nature of $\epsilon_0$ and $\mu_0$
In electromagnetism, the electric displacement field D represents the distribution of electric charges in a given medium resulting from the presence of an electric field E. Its relation to ...
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Why didn't Michelson and Morley assume or conclude that aether is homogenous and permeate all of space?
In the Michelson-Morley experiment, why didn't they assume or conclude that ether is homogeneous and permeate all of space instead of coming from an unspecified source or direction dubbed the ether ...
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Is it possible to distinguish the type of space according to the speed of light in vacuum? [duplicate]
Why is the speed of light 300 000 km/s? The speed of light is slower in glass, water and diamond. Is the speed of light in water, glass and diamond also absolute? Can we calculate the material such as ...
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Why does the assumption that speed of light $c$ is constant exist? [closed]
This is I'm sure a very basic and juvenile question. Why do we take the assumption that $c$ is constant in all situations to be a law? It does work out that it fits the standard model well but it has ...
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How do we know that the speed of light is constant everywhere, not just here? [duplicate]
It might well be that universal constants, say the speed of light, are only constant as far as we can tell in our chunk of the universe - in the same way that the Earth looks flat in the area you live....
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How to rule out that the speed of light was different in the past?
The constancy of the speed of light is a fundamental principle in modern physics, and it is supported by a wide range of current experimental evidence.
There is no evidence to suggest that the speed ...
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Why $cG = 0.02 \rm N$? [closed]
The unit of their product is Newton and its value is precisely (up to their uncertainty) equal to 1/50.
And I know! It is tempting to re-think that they might not be constant, but their product must. ...
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What is the mechanism responsible for the value of the speed of light in vacuum? [duplicate]
First of all, I've read almost all of the similar questions and duplicates given under them. And the question is never answered properly in any of them so please don't just share duplicates and leave ...
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What exactly would it take to show (hypothetically) that the speed of light (in vacuum) is not constant?
Consider Minkowski space, which is determined by the spacetime line element
$$ ds^{2} = -c^{2}dt^{2} + dx^{2} + dy^{2} + dz^{2}. $$
Now suppose we modify this so that the $c$ constant is not a ...
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$G$ expressed as a function of $c$?
The escape velocity for a given mass $M$ and a given radius $r$ is given by:
$v_e = \sqrt{ \frac{2 G M}{r} }$
With $M$ = 25 kg and $r$ = 1/$c$ we have:
$v_e = 1.0001917061 \approx 1$
Can we express $G$...
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If the light was slowing down universally could we detect it? What do we need? [duplicate]
Is there a way to detect it if light was slowing down universally, i.e. if speed of light $c$ in vacuum was getting smaller?
Edit
I was directed to this question. But I did not find the answer I ...
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Using $ct$ axis instead of $t$ axis in special relativity
I've recently started studying the concept of space-time diagrams in special relativity, and I came across the concept of representing the time axis using $ct$, with units being that of length. Now I'...
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Is speed of light a ratio or a universal constant?
We use the speed of light to define the length of the meter, but we also use the speed of light to count the number of clicks on our clocks (because all the electromagnetic events on the smallest ...
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A day with $c=500$ Km/H [closed]
I was reading paradoxes and was doing some problems with unexpected answers on Special relativity. And I find special relativity to be crazy. Sometimes It's hard even to believe these things due to ...
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