Entanglement Production at Instabilities

APS April Meeting 2016, Salt Lake City

Instabilities play a major role in various areas of physics. In this talk, I will present some new results on how instabilities produce entanglement between subsystems. We study the asymptotic behavior of the entanglement entropy when we evolve a squeezed vacuum with an unstable quadratic Hamiltonian. We show that in this setting the entanglement entropy always grows linearly with a slope determined by the classical Lyapunov exponents of the system, resembling the classical Kolmogorov-Sinai entropy rate. Our theorem applies to all bosonic quantum field theories with quadratic coupling, including the scalar Schwinger effect, the inverted mass scalar field and various complex field theory models.