# Bell states

The Bell states are specific quantum states of two qubits that represent the simplest (and maximal) examples of quantum entanglement.

$\vert\Phi^{\pm}\rangle =\frac{\vert 00 \rangle \pm \vert 11 \rangle}{\sqrt{2}}$

$\vert\Psi^{\pm}\rangle =\frac{\vert 01 \rangle \pm \vert 10 \rangle}{\sqrt{2}}$