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arXiv · hep-th/0209093

Interactive Quadratic Gravity

K. Kleidis·A. Kuiroukidis·D. B. Papadopoulos
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Abstract

A quadratic semiclassical theory, regarding the interaction of gravity with a massive scalar quantum field, is considered in view of the renormalizable energy-momentum tensor in a multi-dimensional curved spacetime. According to it, a self-consistent coupling between the square curvature term R^{2} and the quantum field Φshould be introduced in order to yield the "correct" renormalizable energy-momentum tensor in quadratic gravity theories. The subsequent interaction discards any higher-order derivative terms from the gravitational field equations, but, in the expence, it introduces a geometric source term in the wave equation for the quantum field. Unlike the conformal coupling case (RΦ^{2}), this term does not represent an additional "mass" and, therefore, the quantum field interacts with gravity not only through its mass (or energy) content (~Φ^{2}), but also, in a more generic way (R^{2}Φ). Within this context, we propose a general method to obtain mode-solutions for the quantum field, by means of the associated Green's function in an anisotropic six-dimensional background.

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K. Kleidis, A. Kuiroukidis, D. B. Papadopoulos. 2002-09-11. Interactive Quadratic Gravity. https://doi.org/10.1016/s0370-2693(02)02635-7

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