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Is there any intuitive reasoning behind why there would be this universal speed limit? It just seems so arbitrary. I know that there must be things that are unknown, but what reasoning is there behind the existence of some limiting speed?

Edit: I really was asking more abstractly, why it makes sense for there to be a limit. It really is a question that can't be answered, but this isn't a duplicate.

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Yes, the answer is actually very simple:

While you increase the speed, the required amount of energy increases - because with the speed, the objects mass increases. And, to get to the light speed, you'd need infinite amount of energy, and the object itself would have an infinite mass.
You may know that photons, which do move with lightspeed, have zero invariant mass. Now look up this equation:
$$m=\frac{m_0}{\sqrt{1-v^2/c^2}}$$ As you can see, the real mass of the object is the object's invariant mass $m_0$ divided by the $1-speed^2/lightspeed^2$ all squared. Now if we say that speed of the object is lightspeed ($v=c$), we get this:

$$m=\frac{m_0}{\sqrt{1-c^2/c^2}}$$ $$m=\frac{m_0}{\sqrt{1-1}}$$ $$m=\frac{m_0}{0}$$

In complex number system number larger than zero divided by zero equals to infinity, thus $ m=\infty$.
Pure mathematic, no dogmas.

Tomáš Zato
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