Interpretation of Quantum Mechanics

Dinner tonight may be 6 hours later than lunch today. Also, lunch and dinner go from being in our future to being in our present (consecutively) and then our past (consecutively). How do quantum mechanics and relativity account for this?

Dinner today is 6 hours later than lunch. Also they are in our future and then (consecutively) in our present and then (consecutively) in our past. How do both quantum mechanics and relativity account for this?

The centered Everett interpretation solves a problem that various approaches to quantum theory face. In this paper, I continue developing the theory underlying that solution. In particular, I defend the centered Everett interpretation against a few objections, and I provide additional motivation for some of its key features.

The mistake of quantum physics relying on classical physics with its concept of reality confined to mas and space. The mistake of viewing the photon as a particle. The mistake of ignoring the latent identities of entities.

Everettian quantum mechanics tells us that the fundamental dynamics of the universe are deterministic. So what are the `probabilities' that the Born rule describes? One popular answer has been to treat these probabilities as rational credences. A recent alternative, Isaac Wilhelm's centered Everett Interpretation (CEI), takes the Born probabilities to be centered chances: the objective chances that some centered propositions are true. Thus, the CEI challenges the `orthodox assumption’ that fundamental physical laws concern only uncentered facts. I provide three arguments (...) against the centered Everett Interpretation. First, I argue that the CEI is in apparent tension with a significant motivation for adopting Everettian quantum mechanics: rejecting the attribution of special significance to observers or agents in fundamental physics. I suggest the CEI can avoid this tension, but only at the cost of sacrificing its central claim that there are objective chances in an Everettian multiverse. My second argument concerns the CEI’s claim that the centered Born rule is a fundamental physical law. I provide two plausible notions of fundamentality for physical laws, and I argue that the centered Born rule satisfies neither. My final argument is that the CEI’s branch-relative laws cannot explain or constrain an agent’s rational credences in the way that the CEI claims. (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)

The ontology behind quantum mechanics has been the subject of endless debate since the theory was formulated some 100 years ago. It has been suggested, at one time or another, that the objects described by the theory may be individual particles, waves, fields, ensembles of particles, observers, and minds, among many other possibilities. I maintain that these disagreements are due in part to a lack of precision in the use of the theory’s various semantic designators. In particular, there is some (...) confusion about the role of representation, reference, and denotation in the theory. In this article, I first analyze the role of the semantic apparatus in physical theories in general and then discuss the corresponding ontological implications for quantum mechanics. Subsequently, I consider the extension of the theory to quantum fields and then analyze the semantic changes of the designators with their ontological consequences. In addition to the classical arguments to rule out a particle ontology in the case of non-relativistic quantum field theory, I show how the existence of black holes makes the proposal of a particle ontology in general spacetimes unfeasible. I conclude by proposing a provisional pluralistic ontology of fields and spacetime and discussing some prospects for possible future ontological economies. (shrink)

In this article, we discuss some of the challenges related to formulating and adopting a realist position regarding non-relativistic quantum mechanics. In a standard approach to ontology, the ontological commitments of scientific theories can be extracted from them. Scientific realism is the standpoint that our best scientific theories are approximately true, and thus, their ontological commitments, roughly speaking, correspond to reality. Quantum mechanics complicates this view by introducing an interpretational requirement that links a particular conception of how reality should be (...) to the theory. This generates comprehensive difficulties: when we separate theory and interpretation, we have a clear conception of theory but not of interpretation and how to extract its ontology. On the other hand, if we somehow identify theory and interpretation, we have a reasonably clear conception of the desired ontology but lose our best characterizations of theory, rendering our methods for extracting ontology ineffective. Our aim is to map out the challenges for future rigorous realist approaches to quantum mechanics. (shrink)

What's wrong with Copenhagen, GRW, Superdeterminism, QBism, Many-worlds, Bohmianism, and Retrocausality, and how theses differ from Presentist Fragmentalism.

The first purpose of this series of articles is to introduce case studies on how current AI models can be used in the development of a possible theory of quantum gravity, their limitations, and the role the researcher has in steering the development in the right direction, even highlighting the errors, weaknesses and strengths of the whole process. -/- The second is to introduce the new Presentist Fragmentalist ontology as a framework and use it for developing theories of quantum gravity (...) and speculate on achieving a TOE. We emphasize it is necessary for the researcher to check everything in these articles for themselves. While there are many good ideas in this series of papers, the AI is known to make even arithmetic and algebraic mistakes. -/- To select just five apparently good ideas, there is a causal interaction tensor Cαβγδ(F1, F2) that encodes the causal relationship and the strength of the (possibly non-local) interaction between two fragments of reality (formed by each quantum system). There is a quantitative prediction for a testable table-top experiment. There is an explanation of how spacetime emerges from the fragments and their interactions. There is an explicit account of the double-slit experiment. And there is an explanation how this theory accommodates dark matter and dark energy simultaneously. -/- We explore ideas, equations they lead to, concrete calculations, and give corrections along the way. While these are generally morally right within this framework they must be checked by the researcher. Given this caveat, we believe we have made significant progress with the PF interpretation in developing a theory of quantum gravity and pointing out a possible path to a TOE. (shrink)

The first purpose of this series of articles is to introduce case studies on how current AI models can be used in the development of a possible theory of quantum gravity, their limitations, and the role the researcher has in steering the development in the right direction, even highlighting the errors, weaknesses and strengths of the whole process. The second is to introduce the new Presentist Fragmentalist ontology as a framework and use it for developing theories of quantum gravity and (...) speculate on achieving a TOE. We emphasize it is necessary for the researcher to check everything in these articles for themselves. While there are many good ideas in this series of papers, the AI is known to make even arithmetic and algebraic mistakes. To select just five apparently good ideas, there is a causal interaction tensor Cαβγδ(F1, F2) that encodes the causal relationship and the strength of the (possibly non-local) interaction between two fragments of reality (formed by each quantum system). There is a quantitative prediction for a testable table-top experiment. There is an explanation of how spacetime emerges from the fragments and their interactions. There is an explicit account of the double-slit experiment. And there is an explanation how this theory accommodates dark matter and dark energy simultaneously. We explore ideas, equations they lead to, concrete calculations, and give corrections along the way. While these are generally morally right within this framework they must be checked by the researcher. Given this caveat, we believe we have made significant progress with the PF interpretation in developing a theory of quantum gravity and pointing out a possible path to a TOE. (shrink)

This paper continues and extensive exploration of the QG and TOE resulting from the PF interpretation of QM. Some highlights are an exploration of symmetries of the Standard Model, outlines of testable predictions of implications for QG, that this theory can simultaneously give an account of dark matter and dark energy, probabilities and statevector collapse vs. gravity, applications of the causal interaction tensor Cαβγδ(Fi, Fj). Note the first section mentions qualia but this is not a psychological theory this is an (...) ontic theory. (shrink)

This paper continues developing the theory of everything consistent with the Presentist Fragmentalist interpretation of quantum mechanics.

"This self-consistent evolution of the fragments, their causal relationships, and their quantum properties is at the heart of the FCQG-SM framework, providing a unified description of quantum mechanics, general relativity, and the Standard Model.".

This note outlines a Theory of Everything consistent with the PF interpretation of quantum mechanics.

This is an introduction to wave function realism for a compendium on the philosophy of quantum mechanics that will be edited and translated into Portuguese by Raoni Arroyo, entitled Compêndio de Filosofia da Física Quântica. This essay presents the history of wave function realism, its various interpretations, the main arguments that are given for the position, and the main objections that have been raised to it.

In this commentary, I ask six questions concerning the implications of Philipp Berghofer’s experience-first approach for the epistemology of science, in general, and that of quantum mechanics, in particular. His responses will deepen my comprehension of his ideas. I also anticipate that these questions will aid him in further refining and strengthening his arguments.

In this contribution I will retrace the main stages of my research on the objectification problem in quantum mechanics by highlighting some personal memories of my supervisor, the theoretical physicist Giovanni Morchio. The central aim of my MSc thesis was to ask whether the hypothesis of objectification, which is currently added to the formalism, is not, at least in one case, deducible from it and in particular from the dynamics of the temporal evolution. The case study we were looking for (...) had to: 1) represent a situation similar to that in which a macroscopic system such as a measurement apparatus, following interaction with a system, assumes a well-defined state (which or for example represents the fact that the result of a measurement is a particular value), i.e becomes objective 2) represent a fact in nature in which it is not clear whether its explanation can be derived from the formalism of quantum mechanics or whether a hypothesis of objectification is necessary for its explanation. Proving that such a fact can be deduced from the time evolution of quantum mechanics allowed us to conclude that there are cases in which the hypothesis of objectification is superfluous or, in other words, obtainable from the formalism. (shrink)

Three accounts of effective realism (ER) have been advanced to solve three problems for scientific realism: Fraser and Vickers (forthcoming) develop a version of ER about non-relativistic quantum mechanics that they argue is compatible with all the main realist versions (‘interpretations’) of quantum mechanics avoiding the problem of underdetermination among them; Williams (2019) and Fraser (2020b) propose ER about quantum field theory as a response to the problems facing realist interpretations; Robertson and Wilson (forthcoming) propose ER to deal with the (...) dubious ontological status of the entities belonging to superseded theories. This paper argues for the unification of these proposals based on realism about modal structure and the idea of scale relativity of ontology developed by ontic structural realists. This solves problems some or all the accounts of ER face, especially that of making explicit in what way they are realist. Furthermore, we respond to a recent critique that has been raised against the ontic structural realist account of quantum mechanics that we employ. (shrink)

This paper presents and critically discusses the “logos approach to quantum mechanics” from the point of view of the current debates concerning the relation between metaphysics and science. Due to its alleged direct connection with quantum formalism, the logos approach presents itself as a better alternative for understanding quantum mechanics than other available views. However, we present metaphysical and methodological difficulties that seem to clearly point to a different conclusion: the logos approach is on an epistemic equal footing among alternative (...) realist approaches to quantum mechanics. (shrink)

In Everettian quantum mechanics, justifications for the Born rule appeal to self-locating uncertainty or decision theory. Such justifications have focused exclusively on a pure-state Everettian multiverse, represented by a wave function. Recent works in quantum foundations suggest that it is viable to consider a mixed-state Everettian multiverse, represented by a (mixed-state) density matrix. Here, we develop the conceptual foundations for decoherence and branching in a mixed-state multiverse, and extend the standard Everettian justifications for the Born rule to this setting. This (...) extended framework provides a unification of 'classical' and 'quantum' probabilities, and additional theoretical benefits, for the Everettian picture. (shrink)

Bohm’s interpretation of quantum mechanics has generally been received as an attempt to restore the determinism of classical physics. However, although this interpretation, as Bohm initially proposed it in 1952, does indeed have the feature of being deterministic, for Bohm this was never the main point. In fact, in other publications and in correspondence from this period, he argued that the assumption that nature is deterministic is unjustified and should be abandoned. Whereas it has been argued before that Bohm’s commitment (...) to determinism was connected to his interest in Marxism, I argue for the opposite: Bohm found resources in Marxist philosophy for developing a nondeterministic notion of causality, which is based on the idea of infinite complexity and an infinite number of levels of nature. From ca. 1954 onwards, Bohm’s conception of causality further weakened, as he developed the idea of a dialectical relation between causality and chance. (shrink)

The mathematical formalism of quantum theory has been established for nearly a century, yet its physical foundations remain elusive. In recent decades, connections between quantum theory and information theory have garnered increasing attention. This study presents a physical derivation of the mathematical formalism quantum theory based on information-theoretic considerations in physical systems. We postulate that quantum systems are characterized by single independent adjustable variables. Utilizing this physical postulate along with the conservation of total probability, we derive the standard Hilbert space (...) formalism of quantum theory, including the Born probability rule. This comprehensive derivation of quantum theory offers a clear and concise physical foundation for the mathematical formalism of quantum mechanics. (shrink)

في الرابع من أكتوبر (2022)، أعلنت الأكاديمية الملكية السويدية للعلوم في ستوكهولم منح جائزة نوبل في الفيزياء لثلاثة فيزيائيين من جنسيات مختلفة؛ هم: الفرنسي «آلان أسبيه»، والأمريكي «جون فرانسيس كلاوزر»، والنمسوي «أنطون تسايلينغر»، تقديرًا لتجاربهم الرائدة في ميدان ميكانيكا الكم، وبصفة خاصة على صعيد ما يُعرف بالفوتونات المتشابكة، ما يُمهد الطريق لتقنيات جديدة في الحوسبة الكمومية والاتصالات فائقة الأمان. لفهم ما يعنيه هذا، ولماذا اكتسب عملهم هذه الأهمية، نحتاج إلى فهم كيف حسمت هذه التجارب نقاشًا طويل الأمد بين علماء الفيزياء. (...) وكان اللاعب الرئيس في هذا النقاش عالم فيزياء من آيرلندا الشمالية يُدعى «جون ستيورات بل»، نجح في الستينات من القرن العشرين في تبيان كيفية ترجمة سؤال فلسفي ميتافيزيقي حول طبيعة الواقع إلى سؤال فيزيائي يمكن أن يجيب عنه العلم تجريبيًا، وكسر التمييز بين ما نعرفه عن العالم وما يمكن أن يكون عليه العالم حقًا. (shrink)

The paper discusses this year’s Nobel Prize in physics for experiments of entanglement “establishing the violation of Bell inequalities and pioneering quantum information science” in a much wider, including philosophical context legitimizing by the authority of the Nobel Prize a new scientific area out of “classical” quantum mechanics relevant to Pauli’s “particle” paradigm of energy conservation and thus to the Standard model obeying it. One justifies the eventual future theory of quantum gravitation as belonging to the newly established quantum information (...) science. Entanglement, involving non-Hermitian operators for its rigorous description, non-unitarity as well as nonlocal and superluminal physical signals “spookily” (by Einstein’s flowery epithet) synchronizing and transferring some nonzero action at a distance, can be considered to be quantum gravity so that its local counterpart to be Einstein’s gravitation according to general relativity therefore pioneering an alternative pathway to quantum gravitation different from the “secondary quantization” of the Standard model. So, the experiments of entanglement once they have been awarded by the Nobel Prize launch particularly the relevant theory of quantum gravitation grounded on “quantum information science” thus granted to be nonclassical quantum mechanics in the shared framework of the generalized quantum mechanics obeying rather quantum-information conservation than only energy conservation. The concept of “dark phase” of the universe naturally linked to the very well confirmed “dark matter” and “dark energy” and opposed to its “light phase” inherent to classical quantum mechanics and the Standard model obeys quantum-information conservation, after which reversible causality or the mutual transformation of energy and information are valid. The mythical Big Bang after which energy conservation holds universally is to be replaced by an omnipresent and omnitemporal medium of decoherence of the dark and nonlocal phase into the light and local phase. The former is only an integral image of the latter and borrowed in fact rather from religion than from science. Physical, methodological and proper philosophical conclusions follow from that paradigm shift heralded by this year’s Nobel Prize in physics. For example, the scientific theory of thinking should originate from the dark phase of the universe, as well: probably only approximately modeled by neural networks physically belonging to the light phase thoroughly. A few crucial philosophical sequences follow from the break of Pauli’s paradigm: (1) the establishment of the “dark” phase of the universe as opposed to its “light” phase, only to which the Cartesian dichotomy of “body” and “mind” is valid; (2) quantum information conservation as relevant to the dark phase, furthermore generalizing energy conservation as to its light phase, productively allowing for physical entities to appear “ex nihilo”, i.e., from the dark phase, in which energy and time are yet inseparable from each other; (3) reversible causality as inherent to the dark phase; (4) the interpretation of gravitation only mathematically: as an interpretation of the incompleteness of finiteness to infinity, for example, following the Gödel dichotomy (“either contradiction or incompleteness”) about the relation of arithmetic to set theory; (5) the restriction of the concept of hierarchy only to the light phase; (6) the commensurability of both physical extremes of a quantum and the universe as a whole in the dark phase obeying quantum information conservation and akin to Nicholas of Cusa’s philosophical and theological worldview. (shrink)

This paper concerns metaphysical indeterminacy and, in particular, the issue of whether quantum mechanics gives motivation for thinking the world contains it. In a previous paper (Darby G, Pickup M. Synthese 198:1685–1710, 2021), we have offered one way to think about metaphysical indeterminacy which we take to avoid some issues arising from certain features of quantum mechanics (such as the Kochen-Specker theorem). This approach has recently been criticised by Corti (Synthese, forthcoming), and we take this opportunity to respond. Our paper (...) will therefore reply to Corti’s argument, but we also take it as a case study in ‘naturalistic metaphysics’ and hence to contribute to a more general discussion of the relationship between philosophy of science and analytic metaphysics. (shrink)

Max Jammer claimed that, "There can be no doubt that the Danish precursor of modern existentialism and neo-orthodox theology, Soren Kierkegaard, through his influence on Bohr, affected also the course of modern physics to some extent." Despite Jammer's failure to supply sufficient evidence for this claim, I argue that it is not completely off base. In particular, I argue that Kierkegaard and Bohr belong to a common philosophical tradition, and I begin to investigate some of the themes that characterize this (...) tradition. (shrink)

How should we account for the extraordinary regularity in the world? Humeans and Non-Humeans sharply disagree. According to Non-Humeans, the world behaves in an extraordinarily regular way because of certain necessary connections in nature. However, Humeans have thought that Non-Humean views are metaphysically objectionable. In particular, there are two general metaphysical principles that Humeans have found attractive that are incompatible with all existing versions of Non-Humeanism. My goal in this paper is to develop a novel version of Non-Humeanism that is (...) consistent with (and even entails) both of these general metaphysical principles. By endorsing such a view, one can have the explanatory benefits of Non-Humeanism while at the same time avoiding two of the major metaphysical objections towards Non-Humeanism. (shrink)

Within the interdisciplinary field of new materialism Karen Barad’s theory of agential realism deconstructs our current euro-western metaphysical perception of the world and our existence within it, to then re-build an understanding based on relatively new findings within quantum physics. In this thesis I try to recreate Barad’s theory to see what ethical consequences might come from it. Together with practical examples within the discourse of today’s social world and our global connectedness I hope to create a better understanding of (...) the impact of our actions and being on our culture and what we call the natural world. Removing the unique agency given to human culture and language to instead, with the help of post-humanistic ideas, add agency as a universal enactment rather than an attribute, we should start to see ourselves as active and real parts of the world-building that is our home. One main question that I see arise in the end is: what does responsibility entail when we all are one and the same? (shrink)

Throughout these last few decades, phenomenology and modern physics have slowly started to approach each other in order to bridge the gap between subjective and objective. In this thesis I aim to show an approach done with the help of Karen Barad's agential realism; a quantum interpretation enabling us to better understand and analyse our complex world, as well as our perception of it. Taking inspiration from new materialism, phenomenology, and physics, I see a need to properly leave discrete dualism (...) behind, in order to be able to describe cultural and material structures as continuous manifolds. Instead of endlessly searching for their binary and changeless parts. (shrink)

The ontological models framework distinguishes ψ-ontic from ψ-epistemic wave- functions. It is, in general, quite straightforward to categorize the wave-function of a certain quantum theory. Nevertheless, there has been a debate about the ontological status of the wave-function in the statistical interpretation of quantum mechanics: is it ψ-epistemic and incomplete or ψ-ontic and complete? I will argue that the wave- function in this interpretation is best regarded as ψ-ontic and incomplete.

In this popular article, I suggest that the task of interpreting quantum mechanics becomes easier if we reject the view that the quantum universe must be described by a wave function. We should zoom out from the wave function and represent the universe with something more coarse-grained, one that naturally arises from considerations about the Past Hypothesis. The new proposal is called the Wentaculus.

Two of the most difficult problems in the foundations of physics are (1) what gives rise to the arrow of time and (2) what the ontology of quantum mechanics is. They are difficult because the fundamental dynamical laws of physics do not privilege an arrow of time, and the quantum-mechanical wave function describes a high-dimensional reality that is radically different from our ordinary experiences. -/- In this paper, I characterize and elaborate on the ``Wentaculus” theory, a new approach to time’s (...) arrow in a quantum universe that offers a unified solution to both problems. Central to the Wentaculus are (i) Density Matrix Realism, the idea that the quantum state of the universe is objective but can be impure, and (ii) the Initial Projection Hypothesis, a new law of nature that selects a unique initial quantum state. On the Wentaculus, the quantum state of the universe is sufficiently simple to be a law, and the arrow of time can be traced back to an exact boundary condition. It removes the intrinsic vagueness of the Past Hypothesis, eliminates the Statistical Postulate, provides a higher degree of theoretical unity, and contains a natural realization of “strong determinism." I end by responding to four recent objections. In a companion paper, I elaborate on Density Matrix Realism. (shrink)

Functionalism is the view that being x is to play the role of x. This paper defends a functionalist account of three-dimensional entities in the context of Wave Function Realism (WFR), that can explain in detail how we can recover three-dimensional entities out of the wavefunction. In particular, the essay advocates for a novel version of WFR in terms of a functional reductionist approach in the style of David Lewis. This account entails reduction of the upper entities to the bottom (...) ones, when the latter behave appropriately. As applied to WFR, it shows how the wavefunction can turn out to be identical to three-dimensional objects, provided certain conditions. The first major goal of the paper is thus to put forward an improved and more rigorous version of WFR, which dissolves several extant issues about the theory, and can serve as a starting point for future literature on the topic. Moreover, the second major goal of the article is to take WFR as a case study to demonstrate the pros of functional reductionism, especially in the form defended here, thereby helping to bring this view back in the philosophy of science debate. The positive upshots of this paper suggest a possible application of functional reductionism also to other contexts. (shrink)

A book review of _Phenomenological Approaches to Physics_ (2020) edited by H. A. Wiltsche and P. Berghofer.

After about a century since the first attempts by Bohr, the interpretation of quantum theory is still a field with many open questions.1 In this article a new interpretation of quantum theory is suggested, motivated by philosophical considerations. Based on the findings that the ’weirdness’ of quantum theory can be understood to derive from a vanishing distinguishability of indiscernible particles, and the observation that a similar vanishing distinguishability is found for bundle theories in philosophical ontology, the claim is made that (...) quantum theory can be interpreted in an intelligible way by positing a bundle-theoretic view of objective idealism instead of materialism as the underlying fundamental nature of reality. (shrink)

Researchers have suggested since the early days of quantum theory that there are strong analogies between quantum phenomena and mental phenomena and these have developed into a vibrant new field of quantum cognition during recent decades. After revisiting some early analogies by Niels Bohr and David Bohm, this paper focuses upon Bohm and Hiley’s ontological interpretation of quantum theory which suggests further analogies between quantum phenomena and biological and psychological phenomena, including the proposal that the human brain operates in some (...) ways like a quantum measuring apparatus. After discussing these analogies I will also consider, from a quantum perspective, Hintikka’s suggestion that Kant’s notion of things in themselves can be better understood by making an analogy between our knowledge-seeking activities and an elaborate measuring apparatus. (shrink)

در تکوین نظریه محاسبات از اوایل قرن بیستم پارادکسها و خود ارجاعی نقش ویژه ای را بازی کرده اند. هر چند نظریه محاسبات عام بر اساس تعریف ماشین تورینگ، فرض تورینگ_چرچ و کاربردهای آن بنا شده ،اما از همان ابتدا تا به امروز منطق و حوزه های مختلف این علم در ارتباط تنگاتنگ با این تیوری و در ابتدا نظریه محاسبات خاص بوده و این ارتباط روز به روز گسترده و گسترده تر گشته است. از تاثیر پارادوکس دروغگو و پارادکس (...) بری در تمایز میان مفهوم محاسبه پذیر و محاسبه پذیر شمارایانه، قضایای گودل و قضیه چیتین همه جا شاهد این تاثیر و تاثر متقابل هستیم. در این مقال می خواهیم بعد از معرفی اجمالی مطالب باال، تاثیر یک پارادوکس دیگر، پارادوکس اعدام غیر منتظره، را بر این نظریه بررسی نماییم. (shrink)

We give the derivation, as opposed to justification, of the Presentist Fragmentalist interpretation of quantum mechanics in perhaps its most basic form, and then several other considerations.

Lam and Esfeld have argued that, within Bohmian mechanics, the wave function can be interpreted as a physical structure instantiated by the fundamental particles posited by the theory. Further, to characterize the nature of this structure, they appeal to the framework of Ontic Structural Realism, thereby proposing a structuralist interpretation of Bohmian mechanics. However, I shall point out that OSR denotes a family of distinct views, each of which maintains a different account about the relation between structures and objects, and (...) entails a different kind of ontology. Thus, in this paper I will show how to articulate the structuralist approach to Bohmian Mechanics accordingly to the different standard versions of OSR, and I will evaluate these alternatives. Moreover, I will propose a novel and _sui generis_ kind of structuralist interpretation of Bohmian Mechanics, based on the framework of metaphysical coherentism. (shrink)

In this short paper I suggest a few properties a good realist interpretation of quantum mechanics ought to have. Then I canvass several interpretations, most of which do not have these properties, and further suggest problems specific to each one. Then I give a reference to a novel interpretation that solves all of these problems.

On Einstein's Train and the Big Bang in Fragmental Presentism, Temporal Flow Rates, Existence, Free Will, Qualia, Hard Problems, etc.

It is often thought the relativity of simultaneity is inconsistent with presentism. This would be troubling as it conflicts with common sense and—arguably—the empirical data. This note gives a novel fragmentalist-presentist theory that allows for the (non-trivial) relativity of simultaneity. A detailed account of the canonical moving train argument is considered. Alice, standing at the train station, forms her own ontological fragment, in which Bob’s frame of reference, given by the moving train, is modified by the Lorentz transformations. On the (...) other hand, Bob, in the train, forms his own ontological fragment from which Alice’s space and time are modified by the corresponding Lorentz transformations. Each fragment accommodates a unique present moment but does not contain information about the unique present moment of another fragment. This allows for a ‘universal’ present moment that extends throughout space, but only from the perspective of each fragment. The relativity of simultaneity is, as it were, ‘relativised’ to each fragment. This is related to the idea that, roughly speaking, the time of relativity is McTaggart’s (1908) B-series (earlier times to later times) and the time of quantum mechanics is a (fragmentalist) A-series (future/present/past), where these two related series characterize one dimension of time. (shrink)

This is Part 2 of a four part paper, intended as an introduction to the key concepts and issues of time directionality for physicists and philosophers. It redresses some fundamental confusions in the subject. These need to be corrected in introductory courses for physics and philosophy of physics students. Here we analyze the quantum mechanical time reversal operator and the reversal of the deterministic Schrodinger equation. It is argued that quantum mechanics is anti-symmetric w.r.t. time reversal in its deterministic laws. (...) This contradicts the orthodox analysis, found throughout the conventional literature on physical time, which claims that quantum mechanics is time symmetric (reversible), and that we must adopt the anti-unitary operator (T*) instead of the unitary time reversal operator (T) for time reversal in quantum mechanics. This is widely claimed as settled scientific fact, and large metaphysical conclusions about the symmetry of time are drawn from it. But it is an error. (shrink)

This is Part 1 of a four part paper, intended to redress some of the most fundamental confusions in the subject of physical time directionality, and represent the concepts accurately. There are widespread fallacies in the subject that need to be corrected in introductory courses for physics students and philosophers. We start in Part 1 by analysing the time reversal symmetry of quantum probability laws. Time reversal symmetry is defined as the property of invariance under the time reversal transformation, T: (...) t --> -t. It is shown that quantum mechanics (classical or relativistic) is strongly time asymmetric in its probability laws. This contradicts the orthodox analysis, found throughout the conventional literature on physical time, which claims that quantum mechanics is time symmetric or reversible. This is widely claimed as settled scientific fact, and large philosophical and scientific conclusions are drawn from it. But it is an error. The fact is that while quantum mechanics is widely claimed to be reversible on the basis of two formal mathematical properties (that it does have), these properties do not represent invariance under the time reversal transformation. A recent experiment (Batalhão at alia, 2015) showing irreversibility of quantum thermodynamics is discussed as an illustration of this result. Most physicists remain unaware of the errors, decades after they were first demonstrated. Orthodox specialists in the philosophy of time who are aware of the error continue to refer to the ‘time symmetry’ or ‘reversibility’ of quantum mechanics anyway – and exploit the ambiguity to claim false implications about physical time reversal symmetry in nature. The excuse for perpetrating the confusion is that, since it is has now become customary to refer to the formal properties of quantum mechanics as ‘reversibility’ or ‘time reversal symmetry’, we should just keep referring to them by this name, even though they are not time reversal symmetry. This causes endless confusion, in attempts to explain the physical irreversibility of our universe, and in philosophical discussions of implications of physics for the nature of time. The failure of genuine time reversal symmetry in quantum mechanics changes the interpretation of modern physics in a deep way. It changes the problem of explaining the real irreversibility found throughout nature. (shrink)

We start by asking the question of ‘why there is something rather than nothing’ and change this to the question of ‘what are the weakest assumptions for existence’ Eagle [1]. Then we give a kind of Fragmental Perspectivalism. Within this Fragmentalist interpretation of quantum mechanics (each quantum mechanical system forms a fragment) Merriam [2], it turns out McTaggart’s [3] A-series of time (the A-series is future to the present to the past) has a kind of perspectivalism. We then use McTaggart’s (...) A-series and the B-series (the B-series is earlier times to later times) of time to differentiate between how far in the past the big bang was vs. how much earlier than now the big bang was. In one example model, the former goes infinitely far into the past while the latter stays finitely earlier-than. In this model the number of quantum interactions per unit 4-volume goes up to infinity as the big bang is approached from the present epoch. (shrink)

Fragmentalism was originally introduced as a new A-theory of time. It was further refined and discussed, and different developments of the original insight have been proposed. In a celebrated paper, Jonathan Simon contends that fragmentalism delivers a new realist account of the quantum state—which he calls conservative realism—according to which: the quantum state is a complete description of a physical system, the quantum state is grounded in its terms, and the superposition terms are themselves grounded in local goings-on about the (...) system in question. We will argue that fragmentalism, at least along the lines proposed by Simon, does not offer a new, satisfactory realistic account of the quantum state. This raises the question about whether there are some other viable forms of quantum fragmentalism. (shrink)

Nonrelativistic quantum mechanics (QM) works perfectly well for all practical purposes. Once one admits, however, that a successful scientific theory is supposed not only to make predictions but also to tell us a story about the world in which we live, a philosophical problem emerges: in the specific case of QM, it is not possible to associate with the theory a unique scientific image of the world; there are several images. The fact that the theory may be compatible with distinct (...) ontologies, and that those ontologies may themselves be associated with a plurality of metaphysical approaches, gives rise to the problem of metaphysical underdetermination. This paper concludes that the available metametaphysical criteria fail to deliver objectivity in theory choice, and it puts forward its own criterion based on a tension between two methods of metaphysical inquiry: one that is closely related to science and another that is not. (shrink)

Spontaneous collapse theories of quantum mechanics turn the usual Schrödinger equation into a stochastic dynamical law. In particular, in this paper, I will focus on the GRW theory. Two philosophical issues that can be raised about GRW concern (i) the ontology of the theory, in particular the nature of the wave function and its role within the theory, and (ii) the interpretation of the objective probabilities involved in the dynamics of the theory. During the last years, it has been claimed (...) that we can take advantage of dispositional properties in order to develop an ontology for GRW theory, and also in order to ground the objective probabilities which are postulated by it. However, in this paper, I will argue that the dispositional interpretations which have been discussed in the literature so far are either flawed or – at best – incomplete. If we want to endorse a dispositional interpretation of GRW theory we thus need an extended account that specifies the precise nature of those properties and which makes also clear how they can correctly ground all the probabilities postulated by the theory. Thus, after having introduced several different kinds of probabilistic dispositions, I will try to fill the gap in the literature by proposing a novel and complete dispositional account of GRW, based on what I call spontaneous weighted multi-track propensities. I claim that such an account can satisfy both of our desiderata. (shrink)