Live Visualization
Entanglement Visualizer
Measure two qubits repeatedly and watch the correlation pattern emerge. Toggle between an entangled Bell state and two independent qubits to see the difference directly.
Qubit A
Qubit B
What you're actually seeing
When qubits are entangled (specifically, in the Bell state simulated here), measuring one instantly determines what the other will show — even though each individual outcome is genuinely random. This is entanglement: a correlation stronger than anything possible classically, confirmed experimentally through Bell inequality violations.
Why this isn't faster-than-light communication
Even though the correlation is instant, neither qubit's outcome can be controlled — both are still genuinely random. You can't use this to send a message, because there's no way to choose what value you'll measure. This distinction is covered in detail in our Quantum Teleportation lesson, which relies on this same entanglement property.