Theorems are only in math, i.e proofs are only math proofs since you follow certain rules of logic to prove it and once you get the proof no one can say it's wrong if the proof is correct.
Science however cannot have proofs in most cases, so we call Science stuff theories not because they're wrong or just a guess, it's because maybe one time in like the age of the universe a cow would idk float to space and disobey the rules of gravity since it is possible but extremely unlikely we call it a theory and by extremely I mean maybe one time in like 50 times the age of the universe.
