Did the Laws of Physics Emerge at _t_ = 10^{−34} s? Inflation, Reheating and Particle Creation in the Very Early Universe

According to the leading hypothesis in primordial cosmology, the very early universe underwent a rapid phase of accelerated expansion known as cosmological inflation. Inflation ended approximately 10^{−34} s after the expansion began, through a process called reheating, during which the inflaton field decayed into the particles of the Standard Model. In this paper, we do not address questions concerning the empirical adequacy of this cosmological scenario. Instead, we focus on two following questions: 1. According to inflationary cosmology, can we argue that the particles of the Standard Model emerged from the inflaton field, and in what sense? 2. If we claim that the interaction carriers of the Standard Model (e.g., gluons) emerged during reheating, does this imply that the laws governing these interactions (e.g., the strong nuclear force) emerged at the same time? We argue that current models of reheating already provide a clear answer to the first question when interpreted through a diachronic account of emergence. However, the second question may not have a definitive answer, as it depends on one’s metaphysical conception of physical laws. We propose that a powers ontology, according to which laws are based on the causal profile of fundamental dispositional properties, could elegantly accommodate the claim that physical laws emerged in the wake of inflation.