2 citations · 2 across the 3 of their papers we have counts for
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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…
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…
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…
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…
Quantum reference frames, measurement schemes and the type of local algebras in quantum field theory
Christopher J. Fewster, Daan W. Janssen, Leon Deryck Loveridge +2
We develop an operational framework, combining relativistic quantum measurement theory with quantum reference frames (QRFs), in which local measurements of a quantum field on a bac…