Perturbation Theory for Particle in a Box

Abstract

Recently developed strong-coupling theory open up the possibility of treating quantum-mechanical systems with hard-wall potentials via perturbation theory. To test the power of this theory we study here the exactly solvable quantum mechanics of a point particle in a one-dimensional box. Introducing an auxiliary harmonic mass term $m$, the ground-state energy $E^{(0)$ can be expanded perturbatively in powers of $1/md$, where $d$ is the box size. The removal of the infrared cutoff $m$ requires the resummation of the series at infinitely strong coupling. We show that strong-coupling theory yields a fast-convergent sequence of approximations to the well-known quantum-mechanical energy $E^{(0)= π^2/2d^2$.

Author Information under http://www.physik.fu-berlin.de/~kleinert/institution.html . Latest update of paper also at http://www.physik.fu-berlin.de/~kleinert/288

References in corpus (1)

• Strong-Coupling Calculation of Fluctuation Pressure of a Membrane Between Walls

Cited by in corpus (5)

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• Extrapolation of power series by self-similar factor and root approximants
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• Fluctuation Pressure of a Membrane Between Walls Through Five Loops