Semiclassical Statistical Mechanics ∗
نویسندگان
چکیده
We use a semiclassical approximation to derive the partition function for an arbitrary potential in one-dimensional Quantum Statistical Mechanics, which we view as an example of finite temperature scalar Field Theory at a point. We rely on Catastrophe Theory to analyze the pattern of extrema of the corresponding path-integral. We exhibit the propagator in the background of the different extrema and use it to compute the fluctuation determinant and to develop a (nonperturbative) semiclassical expansion which allows for the calculation of correlation functions. We discuss the examples of the single and double-well quartic anharmonic oscillators, and the implications of our results for higher dimensions. Invited talk at the La Plata meeting on ‘Trends in Theoretical Physics’, La Plata, April, 1997 e-mail: [email protected] e-mail: [email protected] 1
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