Distance, it is often argued, is the only coherent and empirically adequate world-making relation that can glue together the elements of the world. This paper offers entanglement as an alternative world-making relation. Entanglement is interesting since it is consistent even with quantum gravity theories that do not feature space at the fundamental level. The paper thereby defends the metaphysical salience of such non-spatial theories. An account of distance is the predominant problem of empirical adequacy facing entanglement as a world-making relation. (...) A resolution of this obstacle utilizes insights from the Ryu–Takayanagi formula and Susskind and Maldacena’s related ER = EPR conjecture. Together these indicate how distance can be recovered from entanglement and thus carves the way for entanglement fundamentalism. (shrink)

Quantum mechanics is arguably our most successful physical theory, yet the nature of the quantum state still constitutes an ongoing controversy. This paper proposes, articulates, and defends a metaphysical interpretation of the quantum state that is fictionalist in spirit since it regards quantum states as representing a fictional ontology. Such an ontology is therefore not physical, and yet it provides a reference for the language used in quantum mechanics and has explanatory power. In this sense, this view, akin to Allori’s (...) recent account of wavefunctionalism, combines elements of the representationalist and anti-representationalist camps and aims to be the best of both worlds. (shrink)

Super-Humeans argue that the most parsimonious ontology of the natural world compatible with our best physical theories consists exclusively of particles and the distance relations between them. This paper argues by contrast that Super-Humean reduction goes insufficiently far, by showing there to be a more parsimonious ontology compatible with physics: Ultimate-Humeanism. This novel view posits an ontology consisting solely of the particles and distance relations required for the existence of a single brain. Super-Humeans impose conditions on what counts as an (...) ontology of the natural world to avoid their view slipping into this kind of ontology, but these conditions are arbitrarily imposed and once this is exposed, Super-Humeans face a dilemma. Either they can embrace Ultimate-Humeanism as the minimal ontology of the natural world compatible with physics, or (more likely) they can rethink the methodology that got them there. Overall, this paper argues that Super-Humeanism currently lacks principled motivation, outlines a framework for naturalistic ontological reductions, and exposes the consequences of unchecked adherence to a simplicity-driven methodology. (shrink)

Within quantum chemistry, the electron clouds that surround nuclei in atoms and molecules are sometimes treated as clouds of probability and sometimes as clouds of charge. These two roles, tracing back to Schrödinger and Born, are in tension with one another but are not incompatible. Schrödinger’s idea that the nucleus of an atom is surrounded by a spread-out electron charge density is supported by a variety of evidence from quantum chemistry, including two methods that are used to determine atomic and (...) molecular structure: the Hartree-Fock method and density functional theory. Taking this evidence as a clue to the foundations of quantum physics, Schrödinger’s electron charge density can be incorporated into many different interpretations of quantum mechanics. (shrink)

I present an exemplary Humean modal epistemology. My version takes inspiration from but incurs no commitment to both Hume’s historical position and Lewis’s Humeanism. Modal epistemology should meet two challenges: the Integration challenge of integrating metaphysics and epistemology and the Reliability challenge of giving an account of how our epistemic capacities can be reliable in detecting modal truth. According to Lewis, modal reasoning starts from certain Humean principles: there is only the vast mosaic of spatiotemporally distributed local matters of fact. (...) The facts can be arbitarily recombined. These principles cannot be taken for granted. I suggest a bottom-up approach instead: Humean principles of recombining the mosaic of facts can be retrieved from the evolutionarily instilled and empirically informed use of imagination in exploring everyday circumstantial possibilities. This use of imagination conforms to a primitive conception of matter as freely recombinable. The modal beliefs that can be obtained from generalizing the more elementary exercise of imagination have to be corrected. Recombination is limited by sortal criteria of identity. Moreover, the overall picture of a recombinable spatiotemporal mosaic must be weighed against the results of science. (shrink)

Humeanism started life as a metaphysical program that could turn out to be false if our best physical theories were to postulate ontological features at odds with Humean ones. However, even if this has arguably already happened, Humeanism is still considered one of the strongest and most appealing metaphysical theories for describing the physical world. What is even more surprising is that a radical Humean thesis—Super-Humeanism—which posits an extremely parsimonious ontology including nothing more than propertyless matter points and their distance (...) relations, is said by its proponents to follow from an attentive reading of our best physical theories. Given its close relationship with physics, Super-Humeans argue that their doctrine conforms to Scientific Realism, offers the ontology that best explains physics’ empirical evidence, and is a naturalistic theory. This paper investigates the strategies that Super-Humeans have adopted to defend these three claims and, more generally, its alleged closeness to physics. I will show that, contrary to what advocates of Super-Humeanism claim, some of its commitments have inevitably created a gap between itself and physics that is difficult to overcome. While it is laudable that Super-Humeans have adopted various strategies to close this gap, no strategy has yet fully succeeded. (shrink)

According to the doctrine of Super-Humeanism, the world’s mosaic consists only of permanent matter points and changing spatial relations, while all the other entities and features figuring in scientific theories are nomological parameters, whose role is merely to build the best law system. In this paper, I develop an argument against Super-Humeanism by pointing out that it is vulnerable to and does not have the resources to solve the well-known problem of immanent comparisons. Firstly, I show that it cannot endorse (...) a fundamentalist solution à la Lewis, since its two pillars—a minimalist ontology and a best system account of lawhood—would generate, together, a tedious problem of internal coherence. Secondly, I consider anti-fundamentalist strategies, proposed within Humeanism, and find them inapplicable to the Super-Humean doctrine. The concern is that, since it is impossible to choose the best law system within Super-Humeanism, this doctrine may be charged with incoherence. (shrink)

Relationism holds that objects entirely depend on relations or that they must be eliminated in favour of the latter. In this article, I raise a problem for relationism. I argue that relationism cannot account for the order in which non-symmetrical relations apply to their relata. In Section 1, I introduce some concepts in the ontology of relations and define relationism. In Section 2, I present the Problem of Order for non-symmetrical relations, after distinguishing it from the Problem of Differential Application. (...) I also examine four main existing strategies to solve it. In Section 3, I develop my argument. The first step consists in arguing that—among those strategies—relationism can only accept directionalism. The second step consists in arguing that directionalism is affected by a serious problem: the Problem of Converses. I also show that relationists who embrace directionalism cannot solve this problem. In Section 4, I introduce and rebut several strategies on behalf of relationists to cope with my argument. In Section 5, I briefly draw some conclusions. (shrink)

According to naturalized metaphysics, metaphysics should be informed by our current best science and not rely on a priori reasoning. Consequently, naturalized metaphysics tends to dismiss metaphysicians’ attempts to quarrel with science. This paper argues that naturalized metaphysics should instead welcome such conflicts between metaphysics and science. Naturalized metaphysics is not eliminative of metaphysics. So, if such conflicts are driven by the immediate absence in science of an answer to a metaphysical question, then the conflict should not be dismissed, but (...) instead be received as an occasion to do naturalized metaphysics. That conflicts between metaphysics and science might be beneficial for naturalized metaphysics is exemplified by the case of non-spatial theories of quantum gravity. These theories are criticized by metaphysicians who, often following David Lewis, argue that spatial distance is an indispensable fundamental element in any coherent metaphysics due to its role as the world-making relation. The resulting conflict, however, is found to be well-motivated since the non-spatial theories of quantum gravity offer no alternative world-making relation to spatial distance. Rather than dismissing this conflict, naturalized metaphysics should therefore receive the Lewisians’ resistance as a call to search for one. How this plays out as a negotiation between the scientific theory and the metaphysical question is exemplified in the last part of the paper where entanglement is proposed as an alternative world-making relation in loop quantum gravity. (shrink)

Quantum mechanics poses several challenges in ontological elucidation. Contextuality threatens determinism and favors realism about possibilia. Indistinguishability challenges traditional identity criteria associated with individual objects. Entanglement favors holistic and relational approaches. These issues, in close connection with different interpretations of quantum mechanics, have given rise to various proposals for the ontology of quantum mechanics. There is a proposal that is realistic about possibilia, where quantum systems are seen as bundles of possible intrinsic properties. This proposal is developed in close connection (...) with modal interpretations and addresses quantum contextuality straightforwardly. There are also proposals based on relations, associated with the relational quantum mechanics interpretation. In this paper, features of these proposals are combined to obtain a modal bundle-theorist relational proposal. Its aim is to consistently and straightforwardly address both contextuality and the holistic and relational aspects of quantum mechanics arising from quantum entanglement. The proposal, if some additional principles are assumed, may turn out to be both an instance of moderate structuralism and priority monism. (shrink)