Murphy's law is more of a saying than an actual law and it has no basis whatsoever in physics.

It states that "Anything and everything that can go wrong will go wrong". This law itself has been around for a very long time, maybe even as long as man has been around, but it was only coined as Murphy's law in the 1940s by George Nichols after he had a bit of a falling out with Edward Murphy who was the reason the law was called Murphy's law.

The law itself doesn't really hold any scientific truth to it and is only useful as a sort of safety reminder or precautionary reminder at the back of people's minds when they're doing certain things, it's basically hoping for the best but expecting the worst.

Murphy's law has even been inverted and used to form yhprum's law which states that 'Anything and everything that can go write will definitely go right'. Murphy's law(Also known as Sod's law) and its inversions are more of mental and psychological laws. They aren't related to physics in anyway whatsoever

I hope this helps.