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arXiv · 2501.00139

Timelike boundary and corner terms in the causal set action

Fay Dowker·Roger Liu·Daniel Lloyd-Jones
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Abstract

The causal set action of dimension $d$ is investigated for causal sets that are Poisson sprinklings into submanifolds of $d$-dimensional Minkowski space. Evidence, both analytic and numerical, is provided for the conjecture that the mean of the causal set action over sprinklings into a manifold with a timelike boundary, diverges like $l^{-1}$ in the continuum limit as the discreteness length $l$ tends to zero. A novel conjecture for the contribution to the causal set action from co-dimension 2 corners, also known as joints, is proposed and justified.

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Fay Dowker, Roger Liu, Daniel Lloyd-Jones. 2024-12-30. Timelike boundary and corner terms in the causal set action. https://doi.org/10.1088/1361-6382%2Fae0be5

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