Physics World

Condensates on crest of a wave

Murray Holland

Published Jul 1, 2002• 0 citations

Abstract

One of the remarkable things about low-temperature physics is that it offers a place where the hidden world of quantum mechanics can be revealed, often giving rise to spectacular effects. In 1995 the Nobel-prize-winning observation of Bose–Einstein condensation showed that a dilute gas of atoms cooled to sufficiently low temperatures could "condense" into an intriguing state in which all the atoms can be described by the same quantum wavefunction.

DOI: 10.1088/2058-7058/15/7/26

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Physics World

Condensates on crest of a wave

Murray Holland

Published Jul 1, 2002• 0 citations

Publisher

Abstract

DOI: 10.1088/2058-7058/15/7/26

Related papers

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L^2

-norm. In particular, we show that this approximate wave function is described in terms of a Bose-Einstein condensate in a one-particle state following the time-dependent Gross-Pitaevskii equation together with pair excitations with respect to this condensate. As a corollary, we establish a central limit theorem for bounded one-particle observables. The second result is a simple proof of Bose-Einstein condensation for interacting, ultra-dilute gases. More specifically, we consider scalings interpolating between the Gross-Pitaevskii regime and the thermodynamic limit. While condensation had been shown to hold in these regimes before, the advantage of the method used here is its simplicity. Lastly, the third result establishes an upper bound on the ground state energy of a dilute Bose gas in the thermodynamic limit. It captures rigorously the third order correction to the energy per unit volume for suﬃciently low densities as predicted in the physics literature first by Wu and subsequently others.

\textit{Full-text embargoed until: 2026-01-01}