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arXiv · hep-th/9805120

A Microscopic Liouville Arrow of Time

John Ellis·N. E. Mavromatos·D. V. Nanopoulos
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Abstract

We discuss the treatment of quantum-gravitational fluctuations in the space-time background as an `environment', using the formalism for open quantum-mechanical systems, which leads to a microscopic arrow of time. After reviewing briefly the open-system formalism, and the motivations for treating quantum gravity as an `environment', we present an example from general relativity and a general framework based on non-critical strings, with a Liouville field that we identify with time. We illustrate this approach with calculations in the contexts of two-dimensional models and $D$ branes. Finally, some prospects for observational tests of these ideas are mentioned.

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John Ellis, N. E. Mavromatos, D. V. Nanopoulos. 1998-05-19. A Microscopic Liouville Arrow of Time. https://doi.org/10.1016/s0960-0779(98)00152-0

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