I consider two possible forms of spacetime emergence according to quantum gravity and cosmology: an inter-level, hierarchical conception (associated with "synchronic emergence"), and an intra-level, `flat' conception of theory emergence (associated with "diachronic emergence"). On the hierarchical conception, spacetime emerges as part of a less fundamental theory, from a more fundamental theory of quantum gravity. On the flat conception, a spatiotemporal model or state emerges from a `prior' (in some sense) model or state that is non-spatiotemporal (or less-than-fully spatiotemporal). I develop a general conception of theory emergence that accommodates these two different forms of emergence, and demonstrate its applicability in several case-studies. I also discuss the implications of these two forms of emergence for reductionism and determinism. (Much of the talk is based on this paper https://philpapers.org/rec/CROABS-4)

Ross Cameron has argued that endurantism requires the A-theory, to make sense of how an enduring object changes its appearance over time. I reply: not all endurantisms. If we adopt an outsourcing account of temporal predication, the argument can be resisted.

Whether or not one holds that time does in fact pass, the B-theorist should appeal to the distinction between primary qualities and secondary qualities in order to explain the link between the passage of time and other temporal features. In the case of the B-theorist illusionist, I will suggest that the illusory experience of temporal passage is better explained by appealing secondary qualities. Further, I will show that it is not the most intuitive for the B-theorist who does accept that time passes to be a reductionist about passage (arguing that our experience of passage can be reduced to some B-theoretic structure). Instead, I will argue that is more intuitive for the B-theorist to hold that temporal passage is a secondary quality explained by the primary quality of some B-theoretic structure. Following this, I will also discuss some other options for the theorist wanting to explain our experience of temporal passage that are possible if we hold that passage is a secondary quality.

It is often thought that quantum mechanics involves metaphysical indeterminacy—that the reality it describes is irresolvably “unsettled.” I argue that this common conception is mistaken. One thing nearly all interpretations of quantum mechanics share is a fundamental ontology that is fully determinate. There is a good reason for this: a theory of physics should be understood in such a way that it is as simple and informative as possible. Interpretations that posit fundamental metaphysical indeterminacy are less simple and informative than interpretations free from indeterminacy. This allows for indeterminacy at non-fundamental levels, but such emergent indeterminacy may be regarded as epistemic or semantic rather than metaphysical. Alternatively, if one allows for emergent metaphysical indeterminacy, then it is likely to be a generic feature of higher-level ontology rather than a novel consequence of quantum mechanics.

Eternalism, the view that what we regard locally as being located in the past, the present and the future equally exists, is the best ontological account of temporal existence in line with special and general relativity. However, special and general relativity are not fundamental theories and several research programs aim at finding a more fundamental theory of quantum gravity weaving together all we know from relativistic physics and quantum physics. Interestingly, some of these approaches assert that time is not fundamental. If time is not fundamental, what does it entail for eternalism and the standard debate over existence in time? First, I will argue that the non-fundamentality of time to be found in string theory entails standard eternalism. Second, I will argue that the non-fundamentality of time to be found in loop quantum gravity entails atemporal eternalism, namely a novel position in the spirit of standard eternalism.

I will respond to some recent arguments regarding the implications that quantum theory has for theories of persistence. (Pashby 2013; Pashby 2016) I will begin by introducing the relevant details about quantum mechanics and the formalism that Thomas Pashby uses in his arguments. Then, I intend to argue against Pashby’s critique of the doctrine of instantaneous temporal parts. Pashby argues that persisting objects in quantum mechanics cannot have temporal parts in the same sense that we might say that they have spatial parts. However, I suggest that those who endorse temporal parts have a range of options to avoid or respond to Pashby’s critique. I will also evaluate his argument that the path of a persisting object cannot be temporally extended, which he uses to rule out Jeremy Butterfield’s gunky perdurantism. Ultimately, I argue that non-relativistic quantum mechanics poses no serious threat to the doctrine of temporal parts.