Philosophy of Physics, Miscellaneous

Physics Overwritten in a new perspective: “Epistemologically Different Worlds” (Einsteins’ relativities without “spacetime”, quantum me-chanics, pre-Big Bang, Big Bangs and “inflation”, dark mat-ter and dark energy, the superstring theory, and Bohr’s com-plementarity) -/- .

The Meaning Circuit Hypothesis (MCH) is a synthesis of ideas providing John Wheeler’s outline of ultimate physics, which he fine-tuned over several decades from the 1970s onward. It is a ‘working hypothesis’ in which ‘existence is a ‘meaning circuit”’ that portrays the world as a “system self-synthesized by quantum networking.” It was strongly advocated by him for roughly two decades and since then has had an increasingly strong impact on the approach of many investigators of quantum theory; in particular, elements (...) such as the quantum participator and ‘it from bit’ are now considered by others as candidate components of a foundation for quantum theory in which information is involved essentially. Therefore, it is worthy of review and critique. (shrink)

With the present paper I maintain that the group field theory (GFT) approach to quantum gravity can help us clarify and distinguish the problems of spacetime emergence from the questions about the nature of the quanta of space. I will show that the mechanism of phase transition suggests a form of indifference between scales (or phases) and that such an indifference allows us to black-box questions about the nature of the ontology of the fundamental levels of the theory. I consider (...) the GFT approach to quantum gravity which derives spacetime as an emergent property from abstract non-geometrical tetrahedra through a processes of phase transition. Because the physical interpretation of the tetrahedra is problematic in view of their (non)-spatiotemporal nature, I will apply the considerations about phase transitions to GFT and conclude that the fundamental ontology of the theory and the mechanism of spacetime emergence can and should be treated separately. (shrink)

According to John D. Norton's Material Theory of Induction, all inductive inferences are justified by local facts, rather than their formal features or some grand principles of nature's uniformity. Recently, Richard Dawid (Found Phys 45(9):1101–1109, 2015) has offered a challenge to this theory: in an adaptation of Norton's own celebrated "Dome" thought experiment, it seems that there are certain inductions that are intuitively reasonable, but which do not have any local facts that could serve to justify them in accordance with (...) Norton's requirements. Dawid's suggestion is that “raw induction” might have a limited but important role for such inferences. I argue that the Material Theory can accommodate such inductions, because there are local facts concerning the combinatoric features of the induction’s target populations that can licence the inferences in an analogous way to existing examples of material induction. Since my arguments are largely independent of the details of the Dome, Norton's theory emerges as surprisingly robust against criticisms of excessive narrowness. (shrink)

I criticize Lockwood’s solution to the “paradoxes” of time travel, thus endorsing Lewis’s more conservative position. Lockwood argues that only in the context of a 5D space-time-actuality manifold is the possibility of time travel compatible with the Autonomy Principle (according to which global constraints cannot override what is physically possible locally). I argue that shifting from 4D space-time to 5D space-time-actuality does not change the situation with respect to the Autonomy Principle, since the shift does not allow us to have (...) a coincidence-free local dynamical theory. (shrink)

A standard line in the contemporary philosophical literature has it that physical theories are equivalent only when they agree on their empirical content, where this empirical content is often understood as being encoded in the equations of motion of those theories. In this article, we question whether it is indeed the case that the empirical content of a theory is exhausted by its equations of motion, showing that (for example) considerations of boundary conditions play a key role in the empirical (...) equivalence (or otherwise) of theories. Having argued for this, we show that philosophical claims made by Knox (2011) that general relativity is equivalent to teleparallel gravity, and by Weatherall (2016) that electromagnetism in the Faraday tensor formalism is equivalent to electromagnetism in the vector potential formalism, can both be called into question. We then show that properly considering the role of boundary conditions in theory structure can potentially restore these claims of equivalence and close with some remarks on the pragmatics of adjudications on theory identity. (shrink)

Idealizations are ubiquitous in physics. They are distortions or falsities that enter into theories, laws, models, and scientific representations. Various questions suggest themselves: What are idealizations? Why do we appeal to idealizations and how do we justify them? Are idealizations essential to physics and, if so, in what sense and for which purpose? How can idealizations provide genuine understanding? If our motivation for believing in the existence of unobservable entities like electrons and quarks is that they are indispensable to our (...) best theories, should we also believe in the existence of indispensable idealizations? This Element will tackle such questions and offer an opinionated and selective introduction to philosophical issues concerning idealizations in physics. Topics to be covered include the concept of and reasons for introducing idealization, abstraction, and approximation, possible taxonomy and justification, and application to issues of mathematical Platonism, scientific realism, and scientific understanding. (shrink)

Idealizations are ubiquitous in physics. They are distortions or falsities that enter into theories, laws, models, and scientific representations. Various questions suggest themselves: What are idealizations? Why do we appeal to idealizations and how do we justify them? Are idealizations essential to physics and, if so, in what sense and for which purpose? How can idealizations provide genuine understanding? If our motivation for believing in the existence of unobservable entities like electrons and quarks is that they are indispensable to our (...) best theories, should we also believe in the existence of indispensable idealizations? This Element will tackle such questions and offer an opinionated and selective introduction to philosophical issues concerning idealizations in physics. Topics to be covered include the concept of and reasons for introducing idealization, abstraction, and approximation, possible taxonomy and justification, and application to issues of mathematical Platonism, scientific realism, and scientific understanding. (shrink)

Susan Stebbing (1885–1943), the UK’s first female professor of philosophy, was a key figure in the development of analytic philosophy. Stebbing wrote the world’s first accessible book on the new polyadic logic and its philosophy. She made major contributions to the philosophy of science, metaphysics, philosophical logic, critical thinking, and applied philosophy. Nonetheless she has remained largely neglected by historians of analytic philosophy. This Element provides a thorough yet accessible overview of Stebbing’s positive, original contributions, including her solution to the (...) paradox of analysis, her account of the relation of sense-data to physical objects, and her anti-idealist interpretation of the new Einsteinian physics. Stebbing’s innovative work in these and other areas helped move analytic philosophy from its early phase to its middle period. (shrink)

Modern physics encompasses theoretical and experimental research divided in subfields with specific features. For instance, high energy physics (HEP) attracts significant funding and has distinct organizational structures, i.e., large laboratories and cross-institutional collaborations. Expensive equipment and large experiments create a specific work atmosphere and human relations. While the gender misbalance is characteristic for STEM, early-career researchers are inherently dependent on their supervisors. This raises the question of how satisfied researchers with working in physics are and how different subgroups – female (...) and early-career researchers – perceive their work environment. We empirically investigated job satisfaction and satisfaction with the academic system among physicists (N=123) working in large laboratories, universities, and independent institutes. The scale for measuring the satisfaction with the academic system in physics yielded three factors: experience of research autonomy, opportunities to use one's knowledge, and appreciation of the research by the general public. The results show that physicists are less satisfied with the academic system than with their work environment. Moreover, female scientists and junior researchers experience their jobs more negatively. The results emphasize the need for improving work and research conditions for underprivileged groups in physics. Interestingly, no significant effect was found between different types of academic institutions and general job satisfaction. Finally, physicists felt that their work has not been well understood by the public. (shrink)

It is generally believed that the de Broglie-Bohm model does not admit a particle interpretation for massive relativistic spin-0 particles, on the basis that particle trajectories cannot be defined. We show this situation is due to the fact that in the standard representation of the Klein-Gordon equation the wavefunction systematically contains superpositions of particle and anti-particle contributions. We argue that by working in a Foldy-Wouthuysen type representation uncoupling the particle from the anti-particle evolutions, a positive conserved density for a particle (...) and associated density current can be defined. For the free Klein-Gordon equation the velocity field obtained from this current density appears to be well-behaved and sub-luminal in typical instances. As an illustration, Bohmian trajectories for a spin-0 boson distribution are computed numerically for free propagation in situations in which the standard velocity field would take arbitrarily high positive and negative values. (shrink)

This essay aims to inquiry into the main factors responsible for the growth of modern acoustics, which basically have to be traced back to the empirical turn occurred in science of music around 1600. Helmholtz’s theory of sound will be regarded as most scientifically significant archetype of modern acoustics. In Section 1 a general historical overview of the science of music will be given and its importance for the development of modern science and mathematics considered. In Section 2 the internal (...) historical roots of modern acoustics, thus of Helmholtz’s theory of sound will be analyzed. Finally, in Section 3 positive and negative elements of Helmholtz’s acoustic will be discussed and its external historical roots as well as its actual epistemological relevance examined. (shrink)

Originally appeared in the field of thermodynamics, the concept of entropy, especially in its statistical acceptation, has found applications in many different disciplines, both inside and outside science. In this work we focus on the possibility of drawing an isomorphism between the entropy of Boltzmann’s statistical mechanics and that of Xenakis’s stochastic music theory. We expose the major technical aspects of the two entropies and then consider affinities and differences between them, both at syntactic and at semantic level, hereto particularly (...) referring to the philosophical problem of the asymmetry of time. (shrink)

Although the Standard Model of particle physics is usually formulated in terms of fields, it can be equivalently formulated in terms of particles and strings. In this picture particles and open strings are always coupled. This offers an intuitive and graphical explanation for the otherwise mysterious gauge symmetry. In addition, the particle–string formulation avoids introducing redundant path integral configurations that are present in the field formulation. For its explanatory power and economy, the particle–string ontology may be preferred over the field (...) ontology for the Standard Model. (shrink)

This is a pdf of a Mathematica calculation that supplements the paper "Presentist Fragmentalism and Quantum Mechanics" forthcoming in Foundations of Physics. In that paper the Born rule (or at least a progenitor) is derived from experimental conditions on the mutual observations of two fragments. In this pdf the experimental conditions are applied to Hilbert space dimensions 3, 4, and 5. It turns out each of these have a 1-dimensional solution space which, it is hoped, can be interpretated as the (...) phase. (shrink)

This paper is concerned with the causally symmetric version of the familiar de Broglie–Bohm interpretation, this version allowing the spacelike nonlocality and the configuration space ontology of the original model to be avoided via the addition of retrocausality. Two different features of this alternative formulation are considered here. With regard to probabilities, it is shown that the model provides a derivation of the Born rule identical to that in Bohm’s original formulation. This derivation holds just as well for a many-particle, (...) entangled state as for a single particle. With regard to “certainties”, the description of a particle’s spin is examined within the model and it is seen that a statistical description is no longer necessary once final boundary conditions are specified in addition to the usual initial state, with the particle then possessing a definite value for every spin component at intermediate times. These values are consistent with being the components of a single, underlying spin vector. The case of a two-particle entangled spin state is also examined and it is found that, due to the retrocausal aspect, each particle possesses its own definite spin during the entanglement, independent of the other particle. In formulating this picture, it is demonstrated how such a realistic model can preserve Lorentz invariance in the face of Bell’s theorem and avoid the need for a preferred reference frame. (shrink)

In this chapter, I argue that Aristotle’s doctrine of hylomorphism, which conceived the natural world as consisting of substances which are metaphysically composed of matter and form, is ripe for rehabilitation in the light of quantum physics. I begin by discussing Aristotle’s conception of matter and form, as it was understood by Aquinas, and how Aristotle’s doctrine of hylomorphism was ‘physicalised’ and eventually abandoned with the rise of microphysicalism. I argue that the phenomenon of quantum entanglement, and the emergence of (...) irreducibly macroscopic phenomena in finite temperature quantum systems, have given us good reasons to doubt the truth of microphysicalism. In support of my argument, I show how to construct a hylomorphic interpretation of the de Broglie-Bohm theory that posits a single Cosmic Substance. I then show how to construct a hylomorphic interpretation of an alternative ‘contextual’ wave function collapse theory (recently proposed by the physicists Barbara Drossel and George Ellis) which posits a plurality of thermal substances. Both of these neo-Aristotelian ontologies reject the microphysicalist dogma that nature consists solely of some set of microscopic constituents. (shrink)

Immanuel Kant’s admiration of the “starry sky” above him and the “moral law” in it has become a philosophical topos today. While the “moral law” is the subject of practical philosophy, Kant refers to an object of astronomy for the main task of theoretical philosophy - namely, to answer the question “What can I know? “. Volume III tackles this question - generalizing to the “hard” sciences of physics, chemistry, and cosmology. It focuses on specific questions that have always been (...) considered “philosophical” in the broadest sense by the interested public and even among physicists themselves: “What is simultaneity at different places?”, “Which interpretation of quantum mechanics is the correct one and what follows from it for our view of the world?” – and, last but not least, “Did the universe exist from eternity or does it have a beginning (and an end)?”. (shrink)

This note gives 9 Temporal Knowledge Arguments and, also, makes a few observations about presentism.

Can we identify potential long-term consequences of digitalisation on public health? Environmental studies, metabolic research, and state of the art research in neurobiology point towards the reduced amount of natural day and sunlight exposure of the developing child, as a consequence of increasingly long hours spent indoors online, as the single unifying source of a whole set of health risks identified worldwide, as is made clear in this review of currently available literature. Over exposure to digital environments, from abuse to (...) addiction, now concerns even the youngest (ages 0 to 2) and triggers, as argued on the basis of clear examples herein, a chain of interdependent negative and potentially long-term metabolic changes. This leads to a deregulation of the serotonin and dopamine neurotransmitter pathways in the developing brain, currently associated with online activity abuse and/or internet addiction, and akin to that found in severe substance abuse syndromes. A general functional working model is proposed under the light of evidence brought to the forefront in this review. (shrink)

Programs in quantum gravity often claim that time emerges from fundamentally timeless physics. In the semiclassical time program time arises only after approximations are taken. Here we ask what justifies taking these approximations and show that time seems to sneak in when answering this question. This raises the worry that the approach is either unjustified or circular in deriving time from no–time.

How is that when scientists need some piece of mathematics through which to frame their theory, it is there to hand? What has been called 'the unreasonable effectiveness of mathematics' sets a challenge for philosophers. Some have responded to that challenge by arguing that mathematics is essentially anthropocentric in character, whereas others have pointed to the range of structures that mathematics offers. Otavio Bueno and Steven French offer a middle way, which focuses on the moves that have to be made (...) in both the mathematics and the relevant physics in order to bring the two into appropriate relation. This relation can be captured via the inferential conception of the applicability of mathematics, which is formulated in terms of immersion, inference, and interpretation. In particular, the roles of idealisations and of surplus structure in science and mathematics respectively are brought to the fore and captured via an approach to models and theories that emphasize the partiality of the available information: the partial structures approach. The discussion as a whole is grounded in a number of case studies drawn from the history of quantum physics, and extended to contest recent claims that the explanatory role of certain mathematical structures in scientific practice supports a realist attitude towards them. The overall conclusion is that the effectiveness of mathematics does not seem unreasonable at all once close attention is paid to how it is actually applied in practice. (shrink)

The dynamic nature of physics cannot be captured through an exclusive focus on the static mathematical formulations of physical theories. Instead, we can more fruitfully think of physics as a set of distinctively social, cognitive, and theoretical/methodological practices. An emphasis on practice has been one of the most notable aspects of the recent “naturalistic turn” in general philosophy of science, in no small part due to the arguments of many feminist philosophers of science. A major project of feminist philosophy of (...) physics has been to shine a critical light on the social and cognitive practices in physics, and how those ultimately influence other aspects of the science. Here we argue that traditional philosophy of physics has focused exclusively on the theoretical/methodological practices of physics, and that feminist philosophy of physics seeks to broaden the focus to include the social and cognitive practices as well. (shrink)

In his [1937, 1938], Paul Dirac proposed his “Large Number Hypothesis” (LNH), as a speculative law, based upon what we will call the “Large Number Coincidences” (LNC’s), which are essentially “coincidences” in the ratios of about six large dimensionless numbers in physics. Dirac’s LNH postulates that these numerical coincidences reflect a deeper set of law-like relations, pointing to a revolutionary theory of cosmology. This led to substantial work, including the development of Dirac’s later [1969/74] cosmology, and other alternative cosmologies, such (...) as the Brans-Dicke modification of GTR, and to extensive empirical tests. We may refer to the generic hypothesis of “Large Number Relations” (LNR’s), as the proposal that there are lawlike relations of some kind between the dimensionless numbers, not necessarily those proposed in Dirac’s early LNH. Such relations would have a profound effect on our concepts of physics, but they remain shrouded in mystery. Although Dirac’s specific proposals for LNR theories have been largely rejected, the subject retains interest, especially among cosmologists seeking to test possible variations in fundamental constants, and to explain dark energy or the cosmological constant. In the first two sections here we briefly summarize the basic concepts of LNR’s. We then introduce an alternative LNR theory, using a systematic formalism to express variable transformations between conventional measurement variables and the true variables of the theory. We demonstrate some consistency results and review the evidence for changes in the gravitational constant G. The theory adopted in the strongest tests of Ġ/G, by the Lunar Laser Ranging (LLR) experiments, assumes: Ġ/G = 3(dr/dt)/r – 2(dP/dt)/P – (dm/dt)/m, as a fundamental relationship. Experimental measurements show the RHS to be close to zero, so it is inferred that significant changes in G are ruled out. However when the relation is derived in our alternative theory it gives: Ġ/G = 3(dr/dt)/r – 2(dP/dt)/P – (dm/dt)/m – (dR/dt)/R. The extra final term (which is the Hubble constant) is not taken into account in conventional derivations. This means the LLR experiments are consistent with our LNR theory (and others), and they do not really test for a changing value of G at all. This failure to transform predictions of LNR theories correctly is a serious conceptual flaw in current experiment and theory. (shrink)

Can we do science without numbers? How much contingency is there? These seemingly unrelated questions--one in the philosophy of math and science and the other in metaphysics--share an unexpectedly close connection. For as it turns out, a radical answer to the second leads to a breakthrough on the first. The radical answer is new view about modality called compossible immutabilism. The breakthrough is a new strategy for doing science without numbers. One of the chief benefits of the new strategy is (...) that, unlike the existing substantialism approach from Field (1980), the new strategy naturally generalizes to theories formulated in terms of state space. (shrink)

In this paper I will defend an approach to the thought experiment known as ‘Maxwell’s Demon’ based on a Maxwellian conception of statistical mechanics. Instead of assuming that thermodynamic descriptions depend reductively on the dynamics of molecular components, I will adopt a conception of thermophysics as a ‘resource theory’ in the Maxwellian line recently defended by Myrvold (2011) and Wallace (2017). From this interpretative stance, Maxwell’s demon would not lead directly to the plausibility of violating the second law of thermodynamics, (...) but to show the pragmatic impossibility of knowing deterministically the exact microscopic of thermal systems. (shrink)

Statistical mechanics is often taken to be the paradigm of a successful inter-theoretic reduction, which explains the high-level phenomena (primarily those described by thermodynamics) by using the fundamental theories of physics together with some auxiliary hypotheses. In my view, the scope of statistical mechanics is wider since it is the type-identity physicalist account of all the special sciences. But in this chapter, I focus on the more traditional and less controversial domain of this theory, namely, that of explaining the thermodynamic (...) phenomena.What are the fundamental theories that are taken to explain the thermodynamic phenomena? The lively research into the foundations of classical statistical mechanics suggests that using classical mechanics to explain the thermodynamic phenomena is fruitful. Strictly speaking, in contemporary physics, classical mechanics is considered to be false. Since classical mechanics preserves certain explanatory and predictive aspects of the true fundamental theories, it can be successfully applied in certain cases. In other circumstances, classical mechanics has to be replaced by quantum mechanics. In this chapter I ask the following two questions: I) How does quantum statistical mechanics differ from classical statistical mechanics? How are the well-known differences between the two fundamental theories reflected in the statistical mechanical account of high-level phenomena? II) How does quantum statistical mechanics differ from quantum mechanics simpliciter? To make our main points I need to only consider non-relativistic quantum mechanics. Most of the ideas described and addressed in this chapter hold irrespective of the choice of a (so-called) interpretation of quantum mechanics, and so I will mention interpretations only when the differences between them are important to the matter discussed. (shrink)

Given an infinite set of finite-sized spheres extending in all directions forever, a finite-sized (relative to the spheres inside the set) observer within the set would view the set as a space composed of discrete, finite-sized objects. A hypothetical infinite-sized (relative to the spheres inside the set) observer would view the set as a continuous space and would see no distinct elements within the set. Using this analogy, the mathematics of infinities, such as the assignment of a cardinality to a (...) set, depends on the reference frame of the observer thinking about them (the mind of the mathematician) relative to the infinite set. This reasoning may also relate to the differing views of space in relativity as continuous and in quantum mechanics as discrete. (shrink)

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)

The second law of thermodynamics is traditionally interpreted as a coarse-grained result of classical mechanics. Recently its relation with quantum mechanical processes such as decoherence and measurement has been revealed in literature. In this paper we will formulate the second law and the associated time irreversibility following Everett’s idea: systems entangled with an object getting to know the branch in which they live. Accounting for this self-locating knowledge, we get two forms of entropy: objective entropy measuring the uncertainty of the (...) state of the object alone, and subjective entropy measuring the information carried by the self-locating knowledge. By showing that the summation of the two forms of entropy is a conserved and perspective-free quantity, we interpret the second law as a statement of irreversibility in knowledge acquisition. This essentially derives the thermodynamic arrow of time from the subjective arrow of time, and provides a unified explanation for varieties of the second law, as well as the past hypothesis. (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)

Recently there is some new interest in understanding the physical reality behind the formalism of quantum mechanics. This paper relates the known “quantum mysteries” of QM with the properties of the underlying structure of discrete space. DOI: 10.5281/zenodo.5236617.

This is a summary presentation of TAU, a theory proposed to explain relativity and unify physics. It is a radical change, because it proposes six dimensions of space, instead of the usual three (normal physics) or nine (string theory). It starts with an alternative foundation for Special Relativity, and leads to a unified theory of physics. It is a realist theory because it is realist about space and time. The TAU concept is briefly introduced here, and its results explained in (...) three main areas, particles, gravity and cosmology. In these areas it makes strong predictions and has several tests. This presentation is based around these applications and the key questions of completing a full particle model, and completing tests of gravity and tests of cosmology. These will decide its fate as an empirical theory. The aim here is to give an overview, in reasonable detail for generalists to see how the model works, but with a minimum of theoretical derivations, so we do not get too bogged down in equations. There are a lot of illustrations instead. Please note this is only a survey of the theory, and a more detailed introduction with proofs follows in Chapters 2-6, where it is developed in stages. In the first half here, we go quickly over the main concepts, in the second half, we give some equations for cosmology and gravity solutions in more detail, because they are more novel. (shrink)

One of the most difficult problems in the foundations of physics is what gives rise to the arrow of time. Since the fundamental dynamical laws of physics are (essentially) symmetric in time, the explanation for time's arrow must come from elsewhere. A promising explanation introduces a special cosmological initial condition, now called the Past Hypothesis: the universe started in a low-entropy state. Unfortunately, in a universe where there are many copies of us (in the distant ''past'' or the distant ''future''), (...) the Past Hypothesis is not enough; we also need to postulate self-locating (de se) probabilities. However, I show that we can similarly use self-locating probabilities to strengthen its rival---the Fluctuation Hypothesis, leading to in-principle empirical underdetermination and radical epistemological skepticism. The underdetermination is robust in the sense that it is not resolved by the usual appeal to 'empirical coherence' or 'simplicity.' That is a serious problem for the vision of providing a completely scientific explanation of time's arrow. (shrink)

I show that centered propositions—also called de se propositions, and usually modeled as sets of centered worlds—pose a serious problem for various versions of Lewis's Principal Principle. The problem, put roughly, is that in scenarios like Elga's `Sleeping Beauty' case, those principles imply that rational agents ought to have obviously irrational credences. To solve the problem, I propose a centered version of the Principal Principle. My version allows centered propositions to be objectively chancy.

The theory of branching space-times, put forward by Belnap, considers indeterminism as local in space and time. In the axiomatic foundations of that theory, so-called choice points mark the points at which the possible future can turn out in different ways. Working under the assumption of choice points is suitable for many applications, but has an unwelcome topological consequence that makes it difficult to employ branching space-times to represent a range of possible physical space-times. Therefore it is interesting to develop (...) a branching space-times theory without choice points. This is what we set out to do in this paper, providing new foundations for branching space-times in terms of choice sets rather than choice points. After motivating and developing the resulting theory in formal detail, we show that it is possible to translate structures of one style into structures of the other style and vice versa. This result shows that the underlying idea of indeterminism as the branching of spatio-temporal histories is robust with respect to different implementations, making a choice between them a matter of expediency rather than of principle. (shrink)

This Open Access book (see link to Taylor & Francis below) critically examines the recent discussions of powers and powers-based accounts of causation. The author then develops an original view of powers-based causation that aims to be compatible with the theories and findings of natural science. Recently, there has been a dramatic revival of realist approaches to properties and causation, which focus on the relevance of Aristotelian metaphysics and the notion of powers for a scientifically informed view of causation. In (...) this book, R.D. Ingthorsson argues that one central feature of powers-based accounts of causation is arguably incompatible with what is today recognised as fact in the sciences, notably that all interactions are thoroughly reciprocal. Ingthorsson’s powerful particulars view of powers-based causation accommodates for the reciprocity of interactions. It also draws out the consequences of that view for the issue of causal necessity and offers a way to understand the constitution and persistence of compound objects as causal phenomena. Furthermore, Ingthorsson argues that compound entities, so understood, are just as much processes as they are substances. A Powerful Particulars View of Causation will be of great interest to scholars and advanced students working in metaphysics, philosophy of science, and neo-Aristotelian philosophy, while also being accessible for a general audience. (shrink)

Knowledge is correct and reliable when its foundation is correct, but humans never have the correct beliefs and methodology. Thus, knowledge is unreliable and the foundation of knowledge needs to be reconstructed. A pure rationalist only believes in logic. Thus, all matter and experience must be propositions derived from logic. The logically necessary consequence of this belief is truth; logically possible consequences are phenomena, and logically impossible consequence are fallacies and evils. This paper introduces belief and its logical consequences, such (...) as discovering first knowledge, both logically and illogically, establishing logical methodology, deducing truths purely through logic, and discovering unprovable truths by imitating the Universe. Logic and illogic are undeniable beliefs, and the reality of the Universe is the ultimate cause of everything. (shrink)

This volume has two primary aims: to trace the traditions and changes in methods, concepts, and ideas that brought forth the logical empiricists’ philosophy of physics and to present and analyze the logical empiricists’ various and occasionally contrary ideas about the physical sciences and their philosophical relevance. These original chapters discuss these developments in their original contexts and social and institutional environments, thus showing the various fruitful conceptions and philosophies behind the history of 20th-century philosophy of science. Logical Empiricism and (...) the Natural Sciences is divided into three thematic sections. Part I surveys the influences on logical empiricism’s philosophy of science and physics. It features chapters on Maxwell’s role in the worldview of logical empiricism, on Reichenbach’s account of objectivity, on the impact of Poincaré on Neurath’s early views on scientific method, Frank’s exchanges with Einstein about philosophy of physics, and on the forgotten role of Kurt Grelling. Part II focuses on specific physical theories, including Carnap’s and Reichenbach’s positions on Einstein’s theory of general relativity, Reichenbach’s critique of unified field theory, and the logical empiricists’ reactions to quantum mechanics. The third and final group of chapters widens the scope to philosophy of science and physics in general. It includes contributions on von Mises’ frequentism; Frank’s account of concept formation and confirmation; and the interrelations between Nagel’s, Feigl’s, and Hempel’s versions of logical empiricism. (shrink)

Review of William B Irvine's "You: A Natural History".

It is relatively easy to state that information retrieval is a scientific discipline but it is rather difficult to understand why it is science because what is science is still under debate in the philosophy of science. To be able to convince others that IR is science, our ability to explain why is crucial. To explain why IR is a scientific discipline, we use a theory and a model of scientific study, which were proposed recently. The explanation involves mapping the (...) knowledge structure of IR to that of well-known scientific disciplines like physics. In addition, the explanation involves identifying the common aim, principles and assumptions in IR and in well-known scientific disciplines like physics, so that they constrain the scientific investigation in IR in a similar way as in physics. Therefore, there are strong similarities in terms of the knowledge structure and the constraints of the scientific investigations between IR and scientific disciplines like physics. Based on such similarities, IR is considered a scientific discipline. (shrink)

The widespread mistrust of metaphysics-the main obstacle to the unification of physics and philosophy-is based on the myth that metaphysical claims cannot be falsified or verified, because they are supposedly true independently of empirical knowledge. This is not true of metaphysical naturalism, whose approach is to critically reflect on the theories and findings of all the empirical disciplines and abstract from them a theory about such general features of reality that no single empirical discipline can be the authority on. Causation (...) is such a feature, since its instances include anything from planetary motions to particle interactions, chemical reactions, biological functions, and closing a door. Consequently, a general account of causation is beyond any particular empirical discipline. Metaphysical naturalism takes a meta-perspective on the results of the empirical sciences and attempts to figure out how it fits together in a coherent whole, e.g. by offering a general account of causation. General accounts of this kind are falsifiable in so far as the theories are falsifiable from which they are generalizations. The paper also discusses some fundamental metaphysical principles implicitly assumed by the sciences generally, and why they imply that unification is methodologically virtuous. (shrink)

The persistent interpretation problem for quantum mechanics may indicate an unwillingness to consider unpalatable assumptions that could open the way toward progress. With this in mind, I focus on the work of David Bohm, whose earlier work has been more influential than that of his later. As I’ll discuss, I believe two assumptions play a strong role in explaining the disparity: 1) that theories in physics must be grounded in mathematical structure and 2) that consciousness must supervene on material processes. (...) I’ll argue that the first assumption appears to lead us toward Everett’s many worlds interpretation, which suggests a red flag. I’ll also argue that the second assumption is suspect due to the persistent explanatory gap for consciousness. Later, I explore ways that Bohm’s later work holds some promise in providing a better fit with our world, both phenomenologically and empirically. Also, I’ll address the possible problem of realism. (shrink)

This survey covers some of the main philosophical debates raised by the framework of effective field theories during the last decades. It is centered on three issues: whether effective field theories underpin a specific realist picture of the world, whether they support an anti-reductionist picture of physics, and whether they provide reasons to give up the ultimate aspiration of formulating a final and complete physical theory. Reviewing the past and current literature, we argue that effective field theories do not give (...) convincing reasons to adopt a particular stance towards these speculative issues. They hold good prospects for asking ontologically perspicuous and sensible questions about currently accessible domains. With respect to more fundamental questions, however, the only certainty is provisional and instrumental: effective theories are currently indispensable for conducting fruitful scientific research. (shrink)

The thesis of the paper maintains it is impossible to disregard a change in the statue of analytical psychology involving the notion of psychoid and its correlation to quantum physics, being psyche not separable from matter. This change finds its most accomplished and impressive epicentre in C.G. Jung and W. Pauli’s theory of synchronicity, in which the Jungian Self becomes the psyche’s quantum psychoid regulatory center, in a Spiritual sense.

Anthropic principle, Perspectival ontology, Hard problem, Why something rather than nothing, Life after death, Buddhism, God.