No-go theorem
In theoretical physics, a no-go theorem is a theorem that states that a particular situation is not physically possible. Specifically, the term describes results in quantum mechanics like Bell's theorem and the Kochen–Specker theorem that constrain the permissible types of hidden variable theories which try to explain the apparent randomness of quantum mechanics as a deterministic model featuring hidden states. Instances of no-go theorems. Full descriptions of the no-go theorems named below are given in other articles linked to their names. A few of them are broad, general categories under which several  theorems fall. Other names are broad and general-sounding but only refer to a single theorem. Proof of impossibility. In mathematics there is the concept of proof of impossibility referring to problems impossible to solve. The difference between this impossibility and that of the no-go theorems is in the fact that the first one is strictly based on logical consequences, .