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arXiv · 1107.0698

Scalar Field Theory on a Causal Set in Histories Form

Rafael D. Sorkin
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Abstract

We recast into histories-based form a quantum field theory defined earlier in operator language for a free scalar field on a background causal set. The resulting decoherence-functional resembles that of the continuum theory. The counterpart of the d'Alembertian operator is nonlocal and is a generalized inverse of the discrete retarded Green function. We comment on the significance of this and we also suggest how to include interactions.

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Rafael D. Sorkin. 2017-02-05. Scalar Field Theory on a Causal Set in Histories Form. https://doi.org/10.1088/1742-6596%2F306%2F1%2F012017

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