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arXiv · 0909.0944

Feynman Propagator for a Free Scalar Field on a Causal Set

Steven Johnston
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Abstract

The Feynman propagator for a free bosonic scalar field on the discrete spacetime of a causal set is presented. The formalism includes scalar field operators and a vacuum state which define a scalar quantum field theory on a causal set. This work can be viewed as a novel regularisation of quantum field theory based on a Lorentz invariant discretisation of spacetime.

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Steven Johnston. 2009-11-02. Feynman Propagator for a Free Scalar Field on a Causal Set. https://doi.org/10.1103/physrevlett.103.180401

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