Craig Callender (left) and Sean Carroll (right) on the arrow of time and the multiverse.
According to the Past Hypothesis, the early universe was a low-entropy state, and entropy has been increasing ever since. Carroll thinks that the truth of the Past Hypothesis cries out for explanation; Callender thinks that its truth should be regarded as a brute law-like fact. They discuss this disagreement. Then (starting at 35:41) they discuss the explanatory merits of Carroll’s proposal that we inhabit a “baby universe” that is an offspring of another, higher-entropy universe.
“Measures, Explanations, and the Past: Should ‘Special’ Initial Conditions Be Explained?” (2004)
SEP entry: “Thermodynamic Asymmetry in Time” (2001/2006)
From Eternity to Here (2010)
with Jennifer Chen: “Spontaneous Inflation and the Origin of the Arrow of Time” (2004)
Blog: Cosmic Variance
Craig Callender and Jonathan Schaffer on meta-metaphysics (PTV)