Quantum Teleportation Protocol: Bell Measurement & Pauli Correction

This simulator walks through the exact mechanics of the standard quantum teleportation protocol, rather than a generic "instantaneous transfer" cartoon. Alice holds an unknown qubit state — set by the θ/φ sliders on its Bloch sphere — and shares a pre-distributed entangled pair with Bob. Running the protocol performs a real Bell-basis measurement (each of the four outcomes occurring with exactly 25% probability, independent of the input state, which is precisely why the two classical bits carry no exploitable information by themselves), animates those bits physically travelling from Alice to Bob, and then applies the matching Pauli correction — Identity, Z, X, or X-then-Z — so that Bob's qubit ends up in exactly the original state. A toggle lets you withhold the correction to see why the classical channel, not faster-than-light signalling, is what makes teleportation work, and a live fidelity readout confirms the reconstructed state matches the original exactly once corrected.