Effective Classical Hamiltonian from Perturbatively Defined Path Integral

Michael Bachmann

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arXiv · 1107.0341

Effective Classical Hamiltonian from Perturbatively Defined Path Integral

Michael Bachmann

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Abstract

Introducing a perturbative definition, phase space path integrals can be calculated without slicing. This leads to a short-time expansion of the quantum-mechanical path amplitude, or a high-temperature expansion of the unnormalized density matrix, respectively. We use the proposed formalism to calculate the effective classical Hamiltonian for the harmonic oscillator.

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Michael Bachmann. 2011-07-01. Effective Classical Hamiltonian from Perturbatively Defined Path Integral. https://arxiv.org/abs/1107.0341

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