# Negative Energy Cosmology and the Cosmological Constant

@article{Prokopec2011NegativeEC, title={Negative Energy Cosmology and the Cosmological Constant}, author={Tomislav Prokopec}, journal={arXiv: Cosmology and Nongalactic Astrophysics}, year={2011} }

It is well known that string theories naturally compactify on anti-de Sitter spaces, and yet cosmological observations show no evidence of a negative cosmological constant in the early Universe's evolution. In this letter we present two simple nonlocal modifications of the standard Friedmann cosmology that can lead to observationally viable cosmologies with an initial (negative) cosmological constant. The nonlocal operators we include are toy models for the quantum cosmological backreaction. In… Expand

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