We conduct a case study analysis of a proposal for the emergence of time based upon the approximate derivation of three grades of temporal structure within an explicit quantum cosmological model which obeys a Wheeler-DeWitt type equation without an extrinsic time parameter. Our main focus will be issues regarding the consistency of the approximations and derivations in question. Our conclusion is that the model provides a self-consistent account of the emergence of chronordinal, chronometric and chronodirected structure. Residual concerns relate to (...) explanatory rather than consistency considerations. (shrink)

The debate between ontological reductionists and emergentists in chemistry has revolved around quantum mechanics. What Franklin and Seifert (BJPS 2020) add to the long-running dispute is an attention to the measurement problem. They contend that all three realist interpretations of the quantum formalism capable of resolving the measurement problem also obviate any need for chemical emergence. I push their argument further, arguing that the realist interpretations of quantum mechanics actually subvert the basis for reduction as well, by undercutting the idea (...) that fundamental physical particles are actual parts of molecules. With both reduction and traditional synchronic emergence pictures ruled out, the only option for realists about quantum chemistry is strong Thomistic emergence. (shrink)

One of the most plausible and widely discussed examples of strong emergence is molecular structure. The only detailed account of it, which has been very influential, is due to Robin Hendry and is formulated in terms of downward causation. This paper explains Hendry’s account of the strong emergence of molecular structure and argues that it is coherent only if one assumes a diachronic reflexive notion of downward causation. However, in the context of this notion of downward causation, the strong emergence (...) of molecular structure faces three challenges that have not been met and which have so far remained unnoticed. First, the putative empirical evidence presented for the strong emergence of molecular structure equally undermines supervenience, which is one of the main tenets of strong emergence. Secondly, it is ambiguous how the assumption of determinate nuclear positions is invoked for the support of strong emergence, as the role of this assumption in Hendry’s argument can be interpreted in more than one way. Lastly, there are understandings of causation which render the postulation of a downward causal relation between a molecule’s structure and its quantum mechanical entities, untenable. (shrink)

By moving away from the traditional reductionist reading of the quantum theory of atoms in molecules, in this paper we analyze the role played by QTAIM in the relationship between molecular chemistry and quantum mechanics from an emergentist perspective. In particular, we show that such a relationship involves two steps: an intra-domain emergence and an inter-domain emergence. Intra-domain emergence, internal to quantum mechanics, results from the fact that the electron density, from which all the other QTAIM’s concepts are defined, arises (...) from the wavefunction as a coarse-grained magnitude. Inter-domain emergence involves an analogical link, a mapping, between QTAIM’s entities, such as topological atoms and bond paths, and the entities that populate the molecular-chemistry domain, such as chemical atoms and chemical bonds. (shrink)

The concepts of molecular structure and molecular shape are ubiquitous in the chemical literature, where they are often taken as synonyms, with unavoidable drawbacks in chemistry teaching. A third concept, molecular topology, is less frequent but it is a reference term in molecular research domains such as Quantitative Structure–Activity Relationships. The present paper proposes an epistemological analysis of these three notions, aimed at clarifying the nature of their relationship, as well as the contiguities and differences between them. At first, we (...) discuss the various acceptations of the terms molecular structure and molecular shape. Then, we examine some crucial milestones in the history of these concepts and we analyse the relationship between structure, shape and topology from an epistemological viewpoint. We point out the distinguishing features of each concept and we show that their semantic openness, that may be fruitful in a specialized context, turns into a source of incoherence and inaccuracy in the teaching context, fostered by the misleading use of these terms made by textbooks. Eventually, we propose a criterion fit to discriminate between the conceptual domains of molecular shape, molecular structure and molecular topology. (shrink)

According to classical molecular chemistry, molecules have a structure, that is, they are sets of atoms with a definite arrangements in space and held together by chemical bonds. The concept of molecular structure is central to modern chemical thought given its impressive predictive power. It is also a very useful concept in chemistry education, due to its role in the rationalization and visualization of microscopic phenomena. However, such a concept seems to find no place in the ontology described by quantum (...) mechanics, since it appeals to classical notions such as the position of the atomic nuclei or the individuality of electrons. Although this problem has attracted the attention of several authors, the discussion is far from settled. Some authors adopt an explicitly reductionist position and advocate to reconstruct the concept of molecular structure within the framework of the quantum theory. Others, although acknowledging the conceptual discontinuity between quantum mechanics and molecular chemistry, keep the hope of future reduction alive. From an explicitly non-reductionist position, on the contrary, others authors conceive molecular structure as an emergent phenomenon. The purpose of this article is to propose a different line of argumentation to address this problem. By contrast to reduction and emergence, the admission of a multiplicity of ontologies, not necessarily linked by hierarchical connections, cancels the need of finding a relation of dependence between the molecular level and the quantum level. This ontologically pluralist position can be applied to the issue of molecular structure, in order to argue that it is possible to admit the existence of structure in the ontology of molecular chemistry, in spite of the fact that it does not exist in the quantum world. (shrink)

In a recent article entitled “The problem of molecular structure just is the measurement problem”, Alexander Franklin and Vanessa Seifert argue that insofar as the quantum measurement problem is solved, the problems of molecular structure are resolved as well. The purpose of the present article is to show that such a claim is too optimistic. Although the solution of the quantum measurement problem is relevant to how the problem of molecular structure is faced, such a solution is not sufficient to (...) account for the structure of molecules as understood in the field of chemistry. (shrink)

The dissemination of models across disciplinary lines has become a phenomenon of interest to philosophers of science. To account for this phenomenon, philosophers have invented two units of analysis. The first identifies to the thing that transfers, model templates. The second identifies the thing to which transferable templates apply, landing zones. There exists a dynamic between the thing that is transferred and the thing to which transferrable templates apply. The use of a transferable template in a new domain requires reconception (...) of domain-specific phenomena. This paper examines two cases of model transfer, the use of the ideal gas law in biology by R.A. Fisher and the use of the virial theorem in chemistry by Richard Bader. These two stories of model transfer in biology and chemistry indicate a dimension to conceptual progress related to this dynamic. Using discourse on model transfer affords philosophers a novel approach for depicting the invention of, for instance, chemical concepts and resulting disputes. (shrink)

The concept of molecular structure is one of the most important concepts of chemistry. In fact, molecular structure is closely related to the concept of chemical substance and its set of properties, and it is the main factor in the explanation of reactivity. In fact, much of the behavior of substances is explained in terms of the structure of their component molecules. This may explain why people tend to take the notion of molecular structure for granted. However, the problem begins (...) already when it comes to specifying the concept, since there is no clear definition of ‘molecular structure’ valid for all chemistry. The purpose of the present article is to show that the term ‘molecular structure’ subsumes very different notions, which depend on how the molecule and its components are conceived, and each of which brings its own difficulties. In particular, we will focus on how the molecule and its structure are devised from a classical view and from a quantum–mechanical view, and will discuss the different problems related with molecular structure that arise in each case. (shrink)

Recent discussions about the microstructure of materials generally focus on the ontological aspects of the molecular structure. However, there are many types of substances that cannot be studied by means of the concept of molecule, for example, salts. For the quantum treatment of these substances, a new particle, called phonon, is introduced. Phonons are generally conceived as a pseudo-particle, that is, a mathematical device necessary to perform calculations but which does not have a "real" existence. In this context, the aim (...) of this paper will be to analyze the ontological status of phonons. For such purposes we will critically analyze the arguments that would account for the presumed nonexistence of phonons. Finally, having already demonstrated that there are not enough reasons to consider phonons as non-existing entities, we will explore some possibilities that allow us to elucidate their ontological status. (shrink)

This essay offers a discussion and contextualisation of a series of letters exchanged between Jordi Cat and Paul Feyerabend from 1989 to 1994. These letters provide insights into Feyerabend’s later thought on a variety of themes including quantum holism, the disunity of science, the development of logical empiricism, and science activism. In doing so, we provide some original analysis and exegesis of Feyerabend’s evolving views on scientific methodology and quantum mechanics by focusing on Feyerabend’s changing attitudes towards Bohm, Bohr, and (...) his eventual colleague Hans Primas and his later sympathies with the algebraic approach. We also highlight Feyerabend’s role in the growth of the Disunity of Science movement and how he connected disunity to practical considerations in the philosophy of action. (shrink)

This thesis develops an account of the nature of wakeful consciousness. Its principal suggestion is that wakeful consciousness is a biological phenomenon and should thus be placed in the context appropriate to biological phenomena. That context is the characterizing form of life of organisms. Once wakeful consciousness is assigned its place in this context, it emerges that wakeful consciousness is a teleological phenomenon, one that is to be understood as having the proper function of putting its bearer in touch with (...) the world. What emerges from reflection on the metaphysics of organisms is an account of wakeful consciousness that is teleological in character but which does not fall foul of the strictures of physicalism and casts new light on recent philosophical debates about consciousness. (shrink)

While temporal considerations are of prime importance for chemical reactions, as well as for molecular stability, most chemical concepts are not explicitly formulated on a diachronic basis. It will be argued here that a formulation explicitly incorporating temporal and epistemological considerations enables us to treat chemical reactions and chemical substances on ontologically equivalent terms, instead of assigning a more fundamental status to the latter. After all, in collision theory, a chemical substance is just a collision complex that takes too long. (...) How long qualifies as “too long”, and “too long” in relation to what, are crucial questions that distinguish chemical substances from chemical reactions, and reversible reactions from irreversible ones, thereby introducing anthropocentric considerations into these distinctions. Too long for a lab chemist is very different from too long for an astrochemist studying chemical reactions between chemical substances in inter-stellar space on cosmological timescales. Examining several physical and chemical properties on the basis of which chemical substances are distinguished from one another, the role of temporal and anthropocentric considerations in defining molecular properties is emphasized. I conclude with some observations on the much-debated reduction of chemistry to other disciplines, arguing that such reduction depends on our aesthetic choices as to what kinds of observations demand explanation, and what kinds of explanation are acceptable. (shrink)