Ground State Energy Fluctuations of a System Coupled to a Bath

K. E. Nagaev; M. Buttiker

doi:10.1209/epl/i2002-00420-8

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Ground State Energy Fluctuations of a System Coupled to a Bath

K. E. Nagaev·M. Buttiker

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Abstract

It is often argued that a small non-degenerate quantum system coupled to a bath has a fixed energy in its ground state since a fluctuation in energy would require an energy supply from the bath. We consider a simple model of a harmonic oscillator (the system) coupled to a linear string and determine the mean squared energy fluctuations. We also analyze the two time correlator of the energy and discuss its behavior for a finite string.

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K. E. Nagaev, M. Buttiker. 2001-12-04. Ground State Energy Fluctuations of a System Coupled to a Bath. https://doi.org/10.1209/epl%2Fi2002-00420-8

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