Ian Jubb (DIAS)
Title: Causal Operations in Quantum Field Theory
Abstract: While Quantum Field Theory is the most accurate theory we have for predicting the microscopic world, there are still open issues regarding its mathematical description. For example, the usual prescription (coming from non-relativistic quantum theory) for certain local operations, e.g. measurements, leads to pathological causality violations in the theory, and hence such local operations must not be physically realisable. It is an open question whether a given local operation in the theory respects causality, and hence whether a given local operation is physical. In this talk I will work through some simple examples of operations that do and do not respect causality, and, if we have enough time, I will lay out a general condition that distinguishes causal and acausal local operations.