Bose-Einstein vs. electrodynamic condensates: the question of order and coherence

E. Del Giudice; G. Preparata

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arXiv · cond-mat/9812018

Bose-Einstein vs. electrodynamic condensates: the question of order and coherence

E. Del Giudice·G. Preparata

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Abstract

The remarkable recent experiments on ensembles of magnetically trapped ultracold alkali atoms have demonstrated the transition to a highly ordered phase, that has been attributed to the process of quantum-mechanical condensation, predicted long ago (1924) by Bose and Einstein. After having presented our argument against the above attribution, we show that the known phenomenology, including a discrepancy of about one order of magnitude with the predictions of Bose- Einstein condensation, is in good agreement with the electromagnetic coherence induced on the alkali atoms by the long range electrodynamic interactions. We also predict that for temperatures lower than a well defined $T_{BEC}$, the state predicted by Bose and Einstein coexists with the new coherent electrodynamic state.

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E. Del Giudice, G. Preparata. 1998-12-01. Bose-Einstein vs. electrodynamic condensates: the question of order and coherence. https://arxiv.org/abs/cond-mat/9812018

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