String Theory, Loop Quantum Gravity and Eternalism

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

Priority Monism Beyond Spacetime

I will defend two claims. First, Schaffer's priority monism is in tension with many research programs in quantum gravity. Second, priority monism can be modified into a view more amenable to this physics. The first claim is grounded in the fact that promising approaches to quantum gravity such as loop quantum gravity or string theory deny the fundamental reality of spacetime. Since fundamental spacetime plays an important role in Schaffer's priority monism by being identified with the fundamental structure, namely the cosmos, the disappearance of spacetime in these views might undermine classical priority monism. My second claim is that priority monism can avoid this issue with two moves: first, in dropping one of its core assumptions, namely that the fundamental structure is spatio-temporal, second, by identifying the connection between the non-spatio-temporal structure and the derivative spatio-temporal structure with mereological composition

The No Self View and the Meaning of Life

Several philosophers, both in Buddhist and Western philosophy, claim that the self does not exist. The no-self view may, at first glance, appear to be a reason to believe that life is meaningless. In the present article, I argue indirectly in favor of the no-self view by showing that it does not entail that life is meaningless. I then examine Buddhism and argue, further, that the no-self view may even be construed as partially grounding an account of the meaning of life

Spacetime Emergence in Quantum Gravity: Functionalism and the Hard Problem

Spacetime functionalism is the view that spacetime is a functional structure implemented by a more fundamental ontology. Lam and Wüthrich have recently argued that spacetime functionalism helps to solve the epistemological problem of empirical coherence in quantum gravity and suggested that it also (dis)solves the hard problem of spacetime, namely the problem of offering a picture consistent with the emergence of spacetime from a non-spatio-temporal structure. First, I will deny that spacetime functionalism solves the hard problem by showing that it comes in various species, each entailing a different attitude towards, or answer to, the hard problem. Second, I will argue that the existence of an explanatory gap, which grounds the hard problem, has not been correctly taken into account in the literature

Contre les défenses du présentisme par le sens commun

According to presentism, only the present exists. The view is in a bad dialectical situation since it has to face several objections based on physics and a priori arguments. The view remains nonetheless popular because it is, allegedly, more intuitive than alternative views, namely eternalism (past, present and future entities exist) and no-futurism (only past and present entities exist). In the essay, I shall not discuss whether intuitivity is an accurate criterion for ontological enquiry. I will rather argue that any philosophically acceptable version of presentism entails highly counterintuitive consequences. Indeed, the presentist has to commit herself to substantial claims in order to provide an answer to two problems : the grounding problem and the cross-temporal relations problem. Therefore, if the main motivation for presentism is the willingness to stick with common sense intuitions, presentists should consider endorsing another view about existence in time

L'éternité sans le temps

L'éternalisme implique une forme exotique d'éternité : toute entité, aussi éphémère soit-elle et quelle que soit sa localisation dans le temps, existe relativement à toute autre localisation temporelle. Cet essai vise, premièrement, à défendre l'éternalisme en exhibant les difficultés rédhibitoires du présentisme et du non-futurisme, et deuxièmement à examiner de quelle manière l'éternalisme pourrait être amendé à l'aune d'une affirmation que l'on trouve sous la plume de certains physiciens, à savoir que, fondamentalement, le temps n'existe pas. La disparition du temps est-elle compatible avec la thèse éternaliste ? Enfin, en guise de conclusion, nous examinerons brièvement une conséquence curieuse de l'éternalisme : bien que mortels, nous sommes des êtres éternels

Les théories méréologiques du faisceau

« Pourquoi les choses tiennent-elles ensemble ? » (Traité d'ontologie, 2009, p. 237). Cette citation me sert de départ à une réflexion sur la nature des relations liantes souvent appelées relations de comprésence à la suite de Russell, ces bundling relations qui nouent les propriétés ensembles pour constituer les objets ordinaires (tables, chaises, individus biologiques) selon la théorie du faisceau. De même que Frédéric Nef, je suis séduit par les nombreuses vertus philosophiques de ces relations liantes. Ma contribution ne portera pas sur une critique ou une défense de ces relations mais sur l'étude de leur nature, et en particulier, de leur possible nature méréologique. Je vais esquisser rapidement certains aspects de la théorie classique du faisceau que je qualifierai de réaliste pour opposer ensuite les variantes réalistes à deux autres versions méréologiques de la théorie, que je qualifierai d'éliminativistes

L'espace et le temps existent-ils ? Le mystère de la gravité quantique

La physique contemporaine pourrait bien nous livrer un enseignement incroyable, à savoir que l'espace et le temps n'existent pas fondamentalement. Je présenterai succinctement les ontologies suggérées par les deux principaux programmes de recherche en gravité quantique : la théorie des cordes et la gravité quantique à boucles. Je soutiendrai ensuite qu'il est fructueux de prendre les différentes conceptions ontologiques de la conscience en philosophie de l'esprit en modèles pour la construction de solutions au problème de l'émergence de l'espace-temps

Space Emergence in Contemporary Physics: Why We Do Not Need Fundamentality, Layers of Reality and Emergence

‘Space does not exist fundamentally: it emerges from a more fundamental non-spatial structure.’ This intriguing claim appears in various research programs in contemporary physics. Philosophers of physics tend to believe that this claim entails either that spacetime does not exist, or that it is derivatively real. In this article, I introduce and defend a third metaphysical interpretation of the claim: reductionism about space. I argue that, as a result, there is no need to subscribe to fundamentality, layers of reality and emergence in order to analyse the constitution of space by non-spatial entities. It follows that space constitution, if borne out, does not provide empirical evidence in favour of a stratified, Aristotelian in spirit, metaphysics. The view will be described in relation to two particular research programs in contemporary physics: wave function realism and loop quantum gravity

String Theory, Loop Quantum Gravity and Eternalism

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