152 citations · 2.3k across the 94 of their papers we have counts for
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Coupled Proca theories: Green-hyperbolicity, quantization and applications to polarization measurement
Christopher J. Fewster, Christiane K. M. Klein
The Proca field describes a massive relativistic spin- particle and was originally formulated in Minkowski spacetime. Here we consider a variety of generalizations in globally h…
On the construction of Hadamard states from Feynman propagators
Christopher J. Fewster, Alexander Strohmaier
The Wightman two-point function of any Hadamard state of a linear quantum field theory determines a corresponding Feynman propagator. Conversely, however, a Feynman propagator dete…
Semi-local observables, edge modes and quantum reference frames in quantum electromagnetism: an algebraic approach
Christopher J. Fewster, Daan W. Janssen, Kasia Rejzner
Boundaries and corners of spacetime play a vital role in understanding physical concepts including entanglement entropy, the infrared problem in QFT and quantum gravity. Standard l…
Polarisation sets of Green operators for normally hyperbolic equations
Christopher J. Fewster
The polarisation set of a vector-valued distribution generalises the wavefront set and captures fibre-directional information about its singularities in addition to their phase spa…
Hadamard states for decomposable Green-hyperbolic operators
Christopher J. Fewster
Hadamard states were originally introduced for quantised Klein-Gordon fields and occupy a central position in the theory of quantum fields on curved spacetimes. Subsequently they h…