Interaction of Quantum Systems with Fundamental Quantum Fields

The recent advent of quantum technologies that are viable at least in a laboratory has opened the prospect of new very high precision tests of fundamental physics. Historically such tests have been confined to a very few special cases. The magnetic dipole moments of the muon and electron are the most stringent of all tests of our theories of fundamental physics. A generation ago measurements of optical polarization rotation caused by parity violations in the weak interactions were a good example of probing fundamental physics with table top experiments; they were also a good example of how very difficult such experiments can be. Now a new generation of technology is available that exploits quantum entanglement and other effects to produce detectors of unparalleled sensitivity.

The Oxford Physics Department is developing a program in the field of very high precision tests of fundamental physics to exploit the world-leading quantum technology expertise we have built up and the state of the art laboratory infrastructure that we have in our new building. The effects we are looking for, whether they originate in gravity, dark matter etc are all caused ultimately by fundamental quantum fields. (And even if that is wrong, to know that it is wrong we still need a detailed understanding of what we expect if it is right.) In parallel with the experimental program it is necessary to develop a systematic theory of the interaction of these fields with the detector. The aim of this project is to develop a first principles quantum field theoretic picture for a model detector whose states are extended and entangled as is typically the case in the detector system in such experiments.