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arXiv · 2109.02590

Vacuum polarisation of Dirac fermions in the cosmological de Sitter-global monopole spacetime

Md Sabir Ali·Sourav Bhattacharya
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Abstract

We study the vacuum polarisation effects of the Dirac fermionic field induced by a pointlike global monopole located in the cosmological de Sitter spacetime. First we derive the four orthonormal Dirac modes in this background in a closed form. Quantising the field using these modes, we then compute the fermionic condensate, $\langle 0| \overlineΨ Ψ| 0\rangle$, as well as the vacuum expectation value of the energy-momentum tensor for a massive Dirac field, regularised in a particular way. We have used the Abel-Plana summation formula in order to extract the global monopole contribution to these quantities and have investigated their variations numerically with respect to relevant parameters.

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Md Sabir Ali, Sourav Bhattacharya. 2022-03-24. Vacuum polarisation of Dirac fermions in the cosmological de Sitter-global monopole spacetime. https://arxiv.org/abs/2109.02590

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