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No Time for Time from No-Time

Published online by Cambridge University Press:  01 January 2022


Programs in quantum gravity often claim that time emerges from fundamentally timeless physics. In the semiclassical time program, time arises only after approximations are taken. Here we ask what justifies taking these approximations and show that time seems to sneak in when answering this question. This raises the worry that the approach is either unjustified or circular in deriving time from no-time.

Physical and Mathematical Sciences
Philosophy of Science , Volume 88 , Issue 5 , December 2021 , pp. 1172 - 1184
Copyright 2021 by the Philosophy of Science Association. All rights reserved.

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We thank Maaneli Derakhshani, Valia Allori, the Southern California Philosophy of Physics Group, and participants of the Workshop in Celebration of David Albert’s Birthday for their comments/feedback.


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