why does physics work differently depending on scale?

Question

I was talking to someone the other day who explained to me that the laws of physics as we understand them are not necessarily ‘rules’ that things on a really tiny scale obey, and the calculations we use to talk about physics on a scale that’s relevant to humans are more like estimations of what will *most probably* happen as a result. This also means there’s no such thing as a perfect circle or a perfect sphere I think? Could someone ELI5?

In: Physics

Answer 1

Physics works differently at different scales due to the principles of quantum mechanics at small scales (atoms and subatomic particles) and general relativity at large scales (cosmological and massive objects). These theories describe phenomena that deviate from classical physics, leading to distinct behaviors in the microscopic and macroscopic worlds.