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arXiv · 1712.04308

Reflection positivity in higher derivative scalar theories

Francesca Arici·Daniel Becker·Chris Ripken·Frank Saueressig·Walter D. van Suijlekom
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Abstract

Reflection positivity constitutes an integral prerequisite in the Osterwalder-Schrader reconstruction theorem which relates quantum field theories defined on Euclidean space to their Lorentzian signature counterparts. In this work we rigorously prove the violation of reflection positivity in a large class of free scalar fields with a rational propagator. This covers in particular higher-derivative theories where the propagator admits a partial fraction decomposition as well as degenerate cases including e.g. p^4 -type propagators.

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Francesca Arici, Daniel Becker, Chris Ripken, Frank Saueressig, Walter D. van Suijlekom. 2017-12-12. Reflection positivity in higher derivative scalar theories. https://doi.org/10.1063/1.5027231

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