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arXiv · 2207.00399

Cosmic time evolution and propagator from a Yang-Mills matrix model

Joanna L. Karczmarek·Harold C. Steinacker
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Abstract

We consider a solution of a IKKT-type matrix model which can be considered as a 1+1-dimensional space-time with Minkowski signature and a Big Bounce-like singularity. A suitable $i\varepsilon$ regularization of the Lorentzian matrix integral is proposed, which leads to the standard $i\varepsilon$-prescription for the effective field theory. In particular, the Feynman propagator is recovered locally for late times. This demonstrates that a causal structure and time evolution can emerge in the matrix model, even on non-trivial geometries. We also consider the propagation of modes through the Big Bounce, and observe an interesting correlation between the post-BB and pre-BB sheets, which reflects the structure of the brane in target space.

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Joanna L. Karczmarek, Harold C. Steinacker. 2022-07-01. Cosmic time evolution and propagator from a Yang-Mills matrix model. https://doi.org/10.1088/1751-8121/acc61e

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