Multiple choice
After this circuit, what is P(|0010⟩) for the whole 4-qubit register measured together (qubit 0 leftmost)?
const c = circuit(4); // 1 & 2: two elementary Bell pairs c.h(0); c.cx(0, 1); c.h(2); c.cx(2, 3); // 3: Bell-state measurement on the repeater qubits (inverse entangler) c.cx(1, 2); c.h(1); // 4: feed-forward corrections onto Bob's qubit (deferred-measurement form) c.cx(2, 3); // X correction conditioned on q2 c.cz(1, 3); // Z correction conditioned on q1 // 5 c.measure(); return c;
Commit your prediction for P(|0010⟩) — then run it.