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Pico-canonical ensembles: A theoretical description of metastable states

Deepak Dhar
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Abstract

We define restricted ensembles, called pico-canonical ensembles, for a statistical-mechanical description of the metastable and glassy phases. In this approach, time-evolution is Markovian, with temperature dependent rates. Below a particular glass-temperature, the system is strongly non-ergodic, and the phase space breaks up into a large number of mutually disconnected sectors. Averages are calculated over states within one such sector, and then averaged over sectors. As a soluble example, we calculate these explicitly for a one dimensional lattice gas with nearest neighbor couplings.

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Deepak Dhar. 2002-05-01. Pico-canonical ensembles: A theoretical description of metastable states. https://doi.org/10.1016/s0378-4371(02)01221-9

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