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arXiv · 2407.08283

From global time to local physics

Syed Moeez Hassan·Viqar Husain·Babar Qureshi
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Abstract

Global time is a gauge or relational choice of time variable in canonical gravity. Local time is the time used in a flat patch of spacetime. We compare the dynamics of a scalar field with respect to choices of global time and Minkowski patch time in an expanding cosmology. Our main results are that evolutions starting from the same initial conditions are similar on the time scales of terrestrial experiments, and that global time leads to a mechanism for evolving coupling constants.

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Syed Moeez Hassan, Viqar Husain, Babar Qureshi. 2024-07-11. From global time to local physics. https://arxiv.org/abs/2407.08283

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