CPT

Calendar of Physics Talks Vienna

MAKING SENSE OF NON-HERMITIAN HAMILTONIANS
Speaker:Prof. Carl M. Bender (Washington University in St. Louis)
Abstract:The average quantum physicist on the street believes that a quantum-mechanical Hamiltonian must be Dirac Hermitian in order to guarantee that the energy eigenvalues are real and that time evolution is unitary. However, the Hamiltonian H=p^2+ix^3, which is obviously not Dirac Hermitian, has a real positive discrete spectrum and generates unitary time evolution, and thus it defines a fully consistent and physical quantum theory! Evidently, the axiom of Dirac Hermiticity is too restrictive. While H=p^2+ix^3 is not Dirac Hermitian, it is PT symmetric; that is, invariant under combined space reflection P and time reversal T. The quantum mechanics defined by a PT-symmetric Hamiltonian is a complex generalization of ordinary quantum mechanics. When quantum mechanics is extended into the complex domain, new kinds of theories having strange and remarkable properties emerge.
Date: Fri, 15.07.2011
Time: 14:00
Duration: 60 min
Location:Seminar room 136, Freihaus, 10th floor (yellow section), Wiedner Hauptstra├če 8-10
Contact:Stefan Rotter