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### Why can't we break the speed of light in vacuum? [duplicate]

I was wondering what could be a possible reason/reasons because of which we cannot break the speed of light barrier. I was reading this where they stated that, Quantum Action Is 10,000 Times Faster ...
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### Why is the speed of light in vacuum a universal constant? [duplicate]

While getting familiar with relativity, the second postulate has me stuck. "The speed of light is constant for all observers". why can't light slow down for an observer travelling the same direction ...
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### Why does the speed of light in vacuum never change? [duplicate]

why does the speed of light in vacuum never change? Under any circumstances, The speed of light in vacuum never change, why?
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### Is a finite lightspeed necessary for cause and effect to exist? [duplicate]

In this question I asked in somewhat unclear (unclear enough to be closed) fashion about the relationship between an infinite speed of light and the existence of cause and effect. In thís question, I ...
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### Can Newton's laws of motion be proved (mathematically or analytically) or are they just axioms?

Today I was watching Professor Walter Lewin's lecture on Newton's laws of motion. While defining Newton's first, second and third law he asked "Can Newton's laws of motion be proved?" and according ...
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### Can a photon get emitted without a receiver?

It is generally agreed upon that electromagnetic waves from an emitter do not have to connect to a receiver, but how can we be sure this is a fact? The problem is that we can never observe non-...
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### Can we tell when an established theory is wrong?

I was reading the following answer from this question: In physics, you cannot ask / answer why without ambiguity. Now, we observe that the speed of light is finite and that it seems to be the ...
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### Why Speed of light in vacuum remains constant? [duplicate]

I know that the speed of light remains constant irrespective of whether the light source is moving or not. But it's very difficult for my brain to visualize it. Light has dual characteristics, i.e. of ...
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### Why should a (physical) principle be applicable to different systems in different positions in space and time?

This is a question with a philosophical, as well as physical, flavor. Why should a physical principle (or a description of one), be applicable to different systems that can be in different positions ...
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### Why is there a universal speed limit?

I am looking for an answer that does not rely on Special or General Relativity -and without recourse to the fact that the speed of light is frame invariant. Is there another way of showing this ...
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### Is the second postulate of Einstein's special relativity an axiom? [closed]

I'm trying to grasp Einstein's special relativity theory and can't seem to find a clear answer as to why Einstein concluded that the speed of light is constant to observers in different inertial ...
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### Gravitational redshift derivation [closed]

When we derive gravitational potential it is dependant only on (rest) mass $m$, but i have seen a derivation of gravitational redshift equation placing relativistic mass $\widetilde{m}$ instead of ...
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### “Why electrons don't fall into nucleus”simple explanation needed [duplicate]

Am studying in 8th grade and I studied electrostatic force which says opposite charge attracts and same charges repel But in an atom electron is just situated above the proton and it doesn't attracts....
Einstein's second postulate of special relativity is: The speed of light in vacuum takes the same value ($c$) for any observer in an inertial frame of reference. I know there is a lot of ...