Entanglement map · Established

When a measure must equal the reduced entropy on pure states

Proved, with a source.

The uniqueness theorem gives necessary and sufficient conditions for a measure to coincide with the von Neumann entropy of the reduced state on pure states. For this case, the question of how much has one answer.

Connections

• Part of: Measures
• See also: Partly entangled pure states concentrate into singlets

Sources

• The uniqueness theorem for entanglement measures. M. J. Donald, M. Horodecki, O. Rudolph, 2001.

Checked 2026-10-30.