Quantum teleportation moves an unknown qubit state from Alice to Bob without ever measuring that state directly, using a shared entangled pair and two classical bits. This simulator walks through all six stages of the protocol, from the initial Bell pair through Bob's final correction, so you can see exactly where entanglement, measurement and classical communication each do their part.
• An adjustable starting state for Alice's qubit, so you can teleport any single-qubit state, not just a fixed example. • A six-step protocol diagram: shared Bell pair, Alice's entangling gates, Alice's measurement, classical bit transmission, Bob's correction, and the completed teleportation. • A simulated random two-bit Bell-measurement outcome at step 2. • Automatic lookup of the correction operation (I, X, Z or XZ) Bob must apply based on those two bits. • Side-by-side Bloch spheres comparing Alice's original state against Bob's qubit at every stage.
• Step through the full protocol once and confirm Bob's final Bloch vector exactly matches Alice's original theta setting, regardless of which random bits came up. • Change Alice's starting theta, reset, and repeat — the protocol works for the same reason on any starting state, not just a special case. • Pause at step 3 (bits sent, correction not yet applied) and note Bob's qubit still looks uninformative until he actually applies the correction in step 4.
No matter or energy moves between Alice and Bob, and no information travels faster than light — the protocol still needs the classical bits to arrive through an ordinary channel before Bob's correction can complete anything. What does transfer is the quantum state itself, and only one copy of it ever exists: Alice's original qubit is left in a random, unrelated state the instant she measures it, which is exactly what the no-cloning theorem requires.
No. Nothing physical travels between Alice and Bob. What moves is quantum information — the exact description of Alice's qubit state — which ends up impressed onto a qubit Bob already possesses, while Alice's original qubit is left in a random, unrelated state after her measurement.
No. The no-cloning theorem forbids creating an independent copy of an unknown quantum state while leaving the original intact. Teleportation never does that — Alice's original qubit is destroyed (randomized) by her measurement in step 3, so there is only ever one copy of the state in existence, just relocated rather than duplicated.
No. Bob's qubit only becomes useful after he receives Alice's two classical bits and applies the corresponding correction, and those bits must travel through an ordinary classical channel that cannot exceed the speed of light. Until they arrive, Bob's qubit looks completely random to him.
Depending on the two classical bits Alice sends, Bob applies one of: do nothing (I), a Pauli X gate, a Pauli Z gate, or X followed by Z. Exactly one of these four corrections always restores his qubit to precisely Alice's original unknown state.