# Causality and cosmic inflation

@article{Vachaspati1998CausalityAC, title={Causality and cosmic inflation}, author={Tanmay Vachaspati and Mark Trodden}, journal={Physical Review D}, year={1998}, volume={61}, pages={023502} }

In the context of inflationary models with a pre-inflationary stage, in which the Einstein equations are obeyed, the null energy condition is satisfied, and spacetime topology is trivial, we argue that homogeneity on super-Hubble scales must be assumed as an initial condition. Models in which inflation arises from field dynamics in a Friedmann-Robertson-Walker background fall into this class but models in which inflation originates at the Planck epoch may evade this conclusion. Our arguments…

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