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Vacuum Polarization Effects on Flat Branes due to a Global Monopole

E. R. Bezerra de Mello
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Abstract

In this paper we analyse the vacuum polarization effects associated with a massless scalar field in the higher-dimensional spacetime. Specifically we calculate the renormalized vacuum expectation value of the square of the field, $<Φ^2(x)>_{Ren}$, induced by a global monopole in the "braneworld" scenario. In this context the global monopole lives in a $n=3$ dimensional sub-manifold of the higher-dimensional (bulk) spacetime, and our Universe is represented by a transverse flat $(p-1)-$ dimensional brane. In order to develop this analysis we calculate the general Green function admitting that the scalar field propagates in the bulk. Also a general curvature coupling parameter between the field and the geometry is assumed. We explicitly show that the vacuum polarization effects depend crucially on the values attributed to $p$. We also investigate the general structure of the renormalized vacuum expectation value of the energy-momentum tensor, $ _{Ren.}$, for $p=3$.

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E. R. Bezerra de Mello. 2006-05-05. Vacuum Polarization Effects on Flat Branes due to a Global Monopole. https://doi.org/10.1103/physrevd.73.105015

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