Linked Questions

8
votes
4answers
3k views

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 ...
3
votes
2answers
114 views

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 ...
29
votes
12answers
13k views

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 ...
38
votes
5answers
5k views

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-...
19
votes
3answers
3k views

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 ...
7
votes
7answers
1k views

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 ...
2
votes
8answers
2k views

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 ...
10
votes
7answers
1k views

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 ...
0
votes
1answer
2k views

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 ...
0
votes
1answer
922 views

“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....
0
votes
4answers
166 views

Different approach of time dilation explanation

Suppose you are going to a distant star, and there is an observer on earth. Usually the answer to the question how long would it take to travel to a distant star is explained this way : You cannot ...
2
votes
2answers
390 views

Can the constancy of the speed of light in vacuum be derived from a deeper theory?

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 ...
-1
votes
4answers
149 views

We all accept/believe in $c$. But what happens when light travels away from the center of gravity of a heavy star? Does it slow down?

I'm basically trying to understand a mysterious characteristic of the universe. Why light has to travel at $c$? I understand and accept that from experiment. Not arguing that it does not. Just saying ...
1
vote
4answers
397 views

Light cone argument for speed of light

Using light cones to state that nothing can travel faster than light to me seems like a flawed argument. (I understand other reasons why the speed of light cannot be broken.) However, it seems to me ...
0
votes
5answers
202 views

Why a body can not be accelerated to speed of light in vacuum? [duplicate]

Well i know that it needs infinite energy..but the term infinite is itself not physical so i am not satisfied with this answer ...but what would happen if we provide a constant acceleration to an ...