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arXiv · 0705.1586

Spacetime Emergence in the Robertson-Walker Universe from a Matrix model

Johanna Erdmenger·Rene Meyer·Jeong-Hyuck Park
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Abstract

Using a novel, string theory-inspired formalism based on a Hamiltonian constraint, we obtain a conformal mechanical system for the spatially flat four-dimensional Robertson-Walker Universe. Depending on parameter choices, this system describes either a relativistic particle in the Robertson-Walker background, or metric fluctuations of the Robertson-Walker geometry. Moreover we derive a tree-level M-theory matrix model in this time-dependent background. Imposing the Hamiltonian constraint forces the spacetime geometry to be fuzzy near the big bang, while the classical Robertson-Walker geometry emerges as the Universe expands. From our approach we also derive the temperature of the Universe interpolating between the radiation and matter dominated eras.

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Johanna Erdmenger, Rene Meyer, Jeong-Hyuck Park. 2007-05-11. Spacetime Emergence in the Robertson-Walker Universe from a Matrix model. https://doi.org/10.1103/physrevlett.98.261301

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