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Causal Sets and an Emerging Continuum
Published 22 May 2024 in gr-qc and hep-th | (2405.14059v3)
Abstract: Causal set theory offers a simple and elegant picture of discrete physics. But the vast majority of causal sets look nothing at all like continuum spacetimes, and must be excluded in some way to obtain a realistic theory. I describe recent results showing that almost all non-manifoldlike causal sets are, in fact, very strongly suppressed in the gravitational path integral. This does not quite demonstrate the emergence of a continuum -- we do not yet understand the remaining unsuppressed causal sets well enough -- but it is a significant step in that direction.
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