Classical space-time geometry in the IKKT matrix model

Harold C. Steinacker

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arXiv · 2204.05679

Classical space-time geometry in the IKKT matrix model

Harold C. Steinacker

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Abstract

We discuss the reconstruction of generic 3+1-dimensional space-time geometries from covariant quantum spaces as backgrounds in the IKKT matrix model. An explicit recipe to realize generic classical geometries is provided. Even though this typically entails some higher-spin contributions, these do not significantly modify the physical content of the model in the weak gravity regime. This justifies the framework for emergent gravity given by the semi-classical matrix model, supplemented by an induced Einstein-Hilbert action which arises in the presence of fuzzy extra dimensions.

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Harold C. Steinacker. 2022-04-12. Classical space-time geometry in the IKKT matrix model. https://arxiv.org/abs/2204.05679

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