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A Microscopic Liouville Arrow of Time

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 نشر من قبل Dr N. Mavromatos
 تاريخ النشر 1998
  مجال البحث فيزياء
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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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