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arXiv · hep-th/9511055

On the Calculation of the Vacuum Energy Density in Sigma Models

V. G. Ksenzov
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Abstract

The vacuum energy density is calculated for the $O(N)$ nonlinear sigma models in two dimensions. To obtain $\varepsilon_{vac}$ we assume that each point of the space in which non-perturbative f\/ields are determined can be replaced by a sphere $S^2$ having a small radius $r$ which approaches zero at the very end of the calculation. This assumption allows to get the classical f\/ields generating v.e.v. of the trace of the energy-momentum tensor.

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V. G. Ksenzov. 1995-11-08. On the Calculation of the Vacuum Energy Density in Sigma Models. https://doi.org/10.1016/0370-2693(95)01420-9

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