Suppose There is a Universe, which has different laws of nature than ours galaxy and they have much greater speed of light than $3* 10^8 $ m/s ,so some person from their universe visits our universe with their speed of speed of light, but since our universe have less speed light, then in our frame of reference, he is moving towards our past. Is it correct, or when he comes to our universe, he is bound to follow our laws of nature?

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    $\begingroup$ Laws of physics are universal $\endgroup$ – Kyle Kanos Aug 14 '19 at 0:38
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    $\begingroup$ In the multiverse theories I am aware of, other universes can have different particles and forces from ours, but constants like $c$ and $\hbar$ are the same across the entire multiverse. $\endgroup$ – G. Smith Aug 14 '19 at 0:48
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    $\begingroup$ ... or if they're not universal then we can't answer based on our own laws. $\endgroup$ – ZeroTheHero Aug 14 '19 at 1:50
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    $\begingroup$ How can we answer your question if the people in the other galaxy use their different laws? $\endgroup$ – Shreyansh Pathak Aug 14 '19 at 4:35
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    $\begingroup$ Just curious. Did you read or hear somewhere that different galaxies can have different laws of physics? $\endgroup$ – m4r35n357 Aug 14 '19 at 8:42

I'm going to stick my neck out here and summarize the comment threads above as an answer of sorts. I'll delete it if it pulls down my reputation score :-/

The universe in which we happen to find ourselves is, as near as we can tell, not structured in a way that would support different values of its fundamental parameters in different locations within it- including the speed of light- for a variety of reasons including (for example) conservation of energy.

Searches for such variations have nonetheless been conducted, with no evidence being uncovered to support those variations either in time or in space.

As such, this makes your question meaningless, which may account for the downvotes it earned so far.

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