Peter Millington: Second quantisation in non-Hermitian field theories

Thursday 27 Jan 2022, 14:00 → 15:00 Europe/London

Second quantisation in non-Hermitian field theories

Abstract: When we first meet quantum mechanics, we are reliably informed that operators corresponding to physical observables, like the energy, should be Hermitian to guarantee that the observables are real.  Thinking about the simpler case of 2x2 matrices, however, it is easy to find matrices with real eigenvalues that are not Hermitian.  The reality of the eigenvalues of such matrices is instead guaranteed by a weaker condition: pseudo-Hermiticity.  In the cases of quantum mechanics and quantum field theory, pseudo-Hermiticity of the Hamiltonian can be related to the existence of an antilinear symmetry, which allows us to construct viable quantum theories, with real spectra and unitary evolution, but whose Hamiltonians are not Hermitian.  In this talk, I will describe the second quantisation of some prototypical non-interacting scalar and fermionic quantum field theories with non-Hermitian Lagrangians, and highlight their potential phenomenological implications for particl!
e physics and cosmology.

Zoom link:  IPPP Seminars (Thursday at 2 pm UK time)

https://durhamuniversity.zoom.us/j/99420124988?pwd=ZEFLSDB3THJtaWZOTU54R25mT1NuZz09

Meeting ID: 994 2012 4988