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arXiv · 1411.2614

Correction terms for propagators and d'Alembertians due to spacetime discreteness

Steven Johnston
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Abstract

The causal set approach to quantum gravity models spacetime as a discrete structure - a causal set. Recent research has led to causal set models for the retarded propagator for the Klein-Gordon equation and the d'Alembertian operator. These models can be compared to their continuum counterparts via a sprinkling process. It has been shown that the models agree exactly with the continuum quantities in the limit of an infinite sprinkling density - the continuum limit. This paper obtains the correction terms for these models for sprinkled causal sets with a finite sprinkling density. These correction terms are an important step towards testable differences between the continuum and discrete models that could provide evidence of spacetime discreteness.

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Steven Johnston. 2014-11-10. Correction terms for propagators and d'Alembertians due to spacetime discreteness. https://doi.org/10.1088/0264-9381/32/19/195020

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