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Letters to Nature
Nature 312, 524 - 527 (06 December 1984); doi:10.1038/312524a0

Inflation in the universe and time asymmetry

P. C. W. Davies

Department of Theoretical Physics, University of Newcastle upon Tyne, Newcastle upon Tyne NE1 7RU, UK

I previously argued that the origin of time asymmetry is to be sought in the processes that characterized the very early cosmological epochs, and that the recent inflationary scenario provides a crucial element in our understanding of this origin1. Here, I develop this thesis further, in the light of criticisms by Page2. I argue in particular that any of the “initial states” that appear to be permitted by quantum gravity, if succeeded by a period of inflation, would have wound up the universe to the state from which, as indicated by increasing entropy, it is now winding down.



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