Title: String compactification metrics, massive spectra, and consistency of quantum gravity

Speaker: Fabian Ruehle (CERN)

Time: 14:45-15:20 (GMT+0), 2021.08.06

Abstract:

Compactifications of string theory imposes strict conditions on the metrics of the compact extra dimensions. The equations of motion dictate that the metrics have reduced holonomy or structure. The partial differential equations describing these conditions are notoriously difficult to solve, which means that explicit metrics are typically not known. However, the form of the metric and its dependence on the shape and size parameters of the compact dimensions are needed to compute massive string excitations and to check conjectured properties that any consistent quantum theory of gravity has to satisfy. We discuss how machine learning and numerical methods can be leveraged to obtain results where exact symbolic results are lacking. As an illustration, we compute the metric and the massive string spectrum in one example and discuss a curious observation relating properties of the spectrum of the Laplace operator to symmetries of the compactification manifold.