In light of its empirical undetectability, physicists have attempted to establish Hawking radiation as universal-as a phenomenon that should appear regardless of the possible details of quantum gravity, whatever those details might be. But, as pointed out in a recent article by Gryb, Palacios, and Thébault (2019), these universality arguments for Hawking radiation seem broadly unconvincing compared to the Wilsonian renormalization-group universality arguments for condensed matter physics.Motivated by their apparent failure, compared with the overwhelming success of universality arguments in so many other contexts, I address the question: in which situations should we expect to be able to construct successful universality arguments? In other words, which situations are 'universality-argument-apt'? I distinguish between two notions of success for a universality argument: 'strength' and 'relevance'. I argue that we should only expect to be able to construct universality arguments that are successful in the sense of being significantly relevant to a given domain if 1 we know enough about how that domain's micro-physics is structured, or 2 we are able to empirically test the domain's macro-behaviour, or if we are in both situations at once. These conditions are useful, most obviously, as a clarification of what universality arguments are capable of. But I argue that they are also useful for two less direct reasons: they clarify the status of analogue experimentation, and thereby show us where we stand in our search for empirical confirmation of Hawking radiation.

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How long does a quantum particle take to traverse a classically forbidden energy barrier? In other words, what is the correct expression for quantum tunnelling time? This seemingly simple question has inspired widespread debate in the physics literature. I argue that we should not expect the orthodox interpretation of quantum mechanics to provide a unique correct expression for quantum tunnelling time, because to do so it would have to provide a unique correct answer to a question whose assumptions are in tension with its core interpretational commitments. I explain how this conclusion connects to time’s special status in quantum mechanics, the meaningfulness of classically inspired concepts in different interpretations of quantum mechanics, the prospect of constructing experimental tests to distinguish between different interpretations, and the status of weak measurement in resolving questions about the histories of subensembles.