Like was there some concrete validation which proved that the laws work same outside the atmosphere of the Earth in space too? Since space was an unknown factor in early days
In: 0
We don’t.
Physics doesn’t allow us to “know” things. Physics allows us to make educated guesses. Someone really clever suggests a theory that *seems* to work. The more it seems to work, the harder we try to disprove it by finding a situation where it fails. The further we go without being able to disprove the theorem, the more confident we become of its validity.
Now, two things:
First, just because a certain law of physics is shown to *not* hold universally doesn’t make it useless. Newtonian mechanics doesn’t work in situations with really fast velocities, or really large masses. Still, it’s the framework NASA uses to land spacecraft on the moon, so in most situations it’s super good enough.
Second, *Science in general* isn’t in the business of pricing things. If I claim that gravity is *actually* caused by invisible magical pixies, there’s not a thing you can do rigorously disprove that. Science operates based on *reasonable doubt*
Lets say I’m on trial for murder. There’s ironclad camera evidence and a signed confession. Does that prove I did it? No, of course not. I can claim that the murder was committed by a robot replica of me from the planet Zorg, and no one can disprove it. Is it reasonable to believe that? Nope, of course not.
In the same way, we assume (some of) the laws of physics behave the same way everywhere in the universe, because that’s the reasonable assumption given our experience.
Latest Answers