What Bell's theorem proved — no local hidden variable theory can reproduce all predictions of quantum mechanics

What does the Kochen-Specker theorem demonstrate regarding the nature of quantum observables and hidden variables theory?

Kochen-Specker theorem disproves non-contextual hidden variables in quantum mechanics

What the Aspect experiments confirmed — Bell inequality violations prove quantum nonlocality is real

Aspect experiments demonstrated quantum entanglement's nonlocality, violating Bell's inequalities

What the EPR paradox challenged — Einstein argued entanglement implied either hidden variables or nonlocality

EPR paradox questioned quantum mechanics' lack of locality and determinism

What the no-cloning theorem prohibits — making an exact copy of an arbitrary unknown quantum state

The no-cloning theorem forbids creating identical copies of an arbitrary unknown quantum state

What the measurement problem asks — why does a quantum superposition collapse to a definite state upon observation

Quantum measurement problem: Superposition collapses due to observer interaction

What the information paradox asks — does information falling into a black hole disappear, violating quantum mechanics

The information paradox questions: Does information vanish in black holes, contradicting quantum theory?