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arXiv · 1506.00895

Semi-classical Dirac vacuum polarisation in a scalar field

Jonas Lampart·Mathieu Lewin
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Abstract

We study vacuum polarisation effects of a Dirac field coupled to an external scalar field and derive a semi-classical expansion of the regu-larised vacuum energy. The leading order of this expansion is given by a classical formula due to Chin, Lee-Wick and Walecka, for which our result provides the first rigorous proof. We then discuss applications to the non-relativistic large-coupling limit of an interacting system, and to the stability of homogeneous systems.

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Jonas Lampart, Mathieu Lewin. 2016-02-23. Semi-classical Dirac vacuum polarisation in a scalar field. https://doi.org/10.1007/s00023-016-0472-y

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