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

We study the vacuum polarization 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. Quantizing the field using these modes, we then compute the fermionic condensate, < 0 vertical bar(Psi) over bar Psi vertical bar 0 >, as well as the vacuum expectation value of the energy-momentum tensor for a massive Dirac field, regularized 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.

Automated summary

We study the vacuum polarization effects of the Dirac fermionic field induced by a pointlike global monopole located in the cosmological de Sitter spacetime. By deriving the four orthornormal Dirac modes in this background and quantizing the field using these modes, we compute the fermionic condensate and the vacuum expectation value of the energy-momentum tensor for a massive Dirac field, and investigate numerically their variations with respect to relevant parameters.