Quantum Entanglement of Local Operators in Conformal Field Theories

Understand

We introduce a series of quantities which characterizes a given local operator in conformal field theories from the viewpoint of quantum entanglement.

• It is defined by the increased amount of (Renyi) entanglement entropy at late time for an excited state defined by acting the local operator on the vacuum.
• We consider a conformal field theory on an infinite space and take the subsystem in the definition of the entanglement entropy to be its half.
• We calculate these quantities for a free massless scalar field theory in 2, 4 and 6 dimensions.