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arXiv · 1907.02903

Form Factors in Asymptotic Safety: conceptual ideas and computational toolbox

Benjamin Knorr·Chris Ripken·Frank Saueressig
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Abstract

Over the last years the Asymptotic Safety program has matured into a serious candidate for a quantum theory of gravity compatible with observations. The rapid technical progress in computing renormalisation group flows for gravity and gravity-matter systems in the non-perturbative regime has put many interesting physical questions within reach. In particular, the construction of the non-perturbative quantum corrections to the propagation of fields on a fluctuating spacetime allows addressing the effective propagation of matter on a quantum spacetime or the possible resolution of spacetime singularities based on first principle computations. In this article, we assemble a technical toolbox for carrying out investigations on this promising research frontier. As a specific example we present results for the momentum-dependent two-point function for a scalar field induced by the quantum fluctuations of the underlying geometry in a self-consistent way.

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Benjamin Knorr, Chris Ripken, Frank Saueressig. 2019-07-05. Form Factors in Asymptotic Safety: conceptual ideas and computational toolbox. https://doi.org/10.1088/1361-6382%2Fab4a53

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