1:30 pm MCP 201

Entanglement entropy is elastic cross section.

I will present universal relations between the cross section, which is the primary observable for high energy particle scattering, and entanglement entropy, which quantifies the quantumness of the process. A careful formulation of incoming wave packets is essential to uncover these relations. We show that for 2-particle scattering with no initial entanglement, the entanglement entropy for elastic final states is the elastic cross section in the unit of the transverse size for the initial wave packets, which can be alternatively interpreted as the elastic scattering probability. This statement does not depend on details of the local dynamics, and is valid to all orders in coupling strength. Furthermore, different ways to partition the system of the two particles lead to final state entanglement entropy expressed as different kinds of semi-inclusive elastic cross sections. Our results imply a version of an area law for entanglement entropy of a two-body system.

## Event Type

**Nov**

**20**