A mechanism describing state reduction dynamics in relativistic quantum field theory is outlined. The mechanism involves nonlinear stochastic modifications to the standard description of unitary state evolution and the introduction of a relativistic field in which a quantized degree of freedom is associated to each point in spacetime. The purpose of this field is to mediate in the interaction between classical stochastic influences and conventional quantum fields. The equations of motion are Lorentz covariant, frame independent, and do (...) not result in divergent behavior. It is shown that the mathematical framework permits the specification of unambiguous local properties providing a connection between the model and evidence of real world phenomena. The collapse process is demonstrated for an idealized example. (shrink)

This paper examines some physical sources of the concept of objective state reduction in quantum mechanics. Using case studies from nuclear physics and quantum chemistry, the question of whether one can induce a collapse theory from the practices of scientists working on specific problems is considered. A specific proposal is explored, with emphasis on such features as coherence, testability, unifying power and fertility. It is shown that, contrary to recent suggestions by David Albert, collapse theories are philosophically promising (...) developments worthy of further study. Some philosophical implications of the development of collapse theories are discussed. (shrink)

The search for a coherent and fertile interpretation of quantum mechanics [QM] with collapse of the wave function is currently a hot topic. This paper focuses on the following sets of related issues: 1) In what sense, if any, do collapse theories constitute a view of the quantum world induced “from the practices-up”? [Here and throughout the paper the term “a view from the practices-up” will mean a view induced from the practices of scientists working on specific problems.] 2) What (...) general description does a collapse variant of QM yield of the physical world? What interpretative problems, if any, does it solve? How exactly does it differ from current mainstream versions of QM? What problems does it face? How serious are these problems in light of current background knowledge?. 3) In our present scientific and philosophical circumstances, what, if anything, makes the search for collapse theories an attractive program? (shrink)

In this paper I will present conceptions of state reduction and particle and/or system localization which render these subjects fully compatible with the general requirements of a relativistic, i.e. Lorentz invariant, quantum theory. The approach consists of a systematic generalization of the concepts of initial data assignment at definite times, initiation and completion of measurements at definite times, and dynamical evolution as time dependence, to the concepts of initial data assignment on arbitrary space-like hyperplanes, initiation and completion of (...) measurements on arbitrary space-like hyperplanes, and dynamical evolution as space-like hyperplane dependence, respectively. I also briefly discuss the superluminal propagation which emerges from the localization study and the manner in which causal anomalies are nevertheless avoided. (shrink)

This is the first of two papers responding to ‘recent’ commentary on various aspects of hyperplane dependence by several authors. In this paper I focus on the issues of the relations of HD to state reduction and unitary evolution. The authors who’s comments I address here are Maudlin and Myrvold. In the second paper of this set I focus on HD dynamical variables and localizable properties and measurements and address comments of de Koning, Halvorson, Clifton and Wallace. Each (...) paper ends with some reflections on the implications of HD for the ontology of Minkowski space-time. To set the stage for my responses, I begin this paper with some general position statements designed to correct what seem to be widespread and erroneous construals of some of my views. Two central points are argued for in this first paper. First, dynamical evolution occurs not only within foliations of Minkowski space-time. Rather the transition from the physical state of affairs on any one hyperplane to any other, whether the hyperplanes intersect or are parallel, is always an instance of dynamical evolution between them, generated by some active combination of boost-like transformations and/or time-like translations and/or state reductions and ‘reconstructions’. This point gives rise to a generalized conception of a history of dynamical evolution, allowing for the use of parameterized families of hyperplanes that multiply cover some portions of space-time. Nevertheless, and this is the second central point, for any two generalized histories, H and H’, the quantum states for a system on all the hyperplanes of H from the asymptotic past up to some hyperplane, h, determine the quantum states for the system on all the hyperplanes of H’ from the asymptotic past up to any hyperplane, h’, such that h’ lies to the past of all those state reduction regions that lie to the future of all hyperplanes of H that are ‘earlier’ than h. Consideration of these results should defuse concerns that have been voiced about the coherence and consistency of HD. A position closely related to the second point has already been argued for by Myrvold. (shrink)

Entanglement has been called the most important new feature of the quantum world. It is expressed in the quantum formalism by the joint measurement formula. We prove the formula for projection valued observables from a plausible assumption, which for spacelike separated measurements is an expression of relativistic causality. The state reduction formula is simply a way to express the joint measurement formula after one measurement has been made, and its result known.

The central problem in the quantum theory of measurement, how to describe the process of state reduction in terms of the quantum mechanical formalism, is solved on the basis of the relativity of quantal states, which implies that once the apparatus is detected in a well-defined state, the object state must reduce to a corresponding one. This is a process termed by Schrödinger disentanglement. Here, it is essential to observe that Renninger's negative result does constitute an (...) actual measurement process. From this point of view, Heisenberg's interpretation of his microscope experiment and the Einstein-Podolsky-Rosen arguments are reinvestigated. Satisfactory discussions are given to various experimental situations, such as the Stern-Gerlach-type experiment, successive measurements, macroscopic measurements, and Schrödinger's cat. Finally it is proposed to regard a state vector in quantum mechanics as an irreducible physical construct, in Margenau's sense, that is not further analyzable both mathematically and conceptually. (shrink)

It is pointed out that the Diosi-Penrose ansatz for gravity-induced quantum state reduction can be tested by observing oscillations in the flavor ratios of neutrinos originated at cosmological distances. Since such a test would be almost free of environmental decoherence, testing the ansatz by means of a next generation neutrino detector such as IceCube would be much cleaner than by experiments proposed so far involving superpositions of macroscopic systems. The proposed microscopic test would also examine the universality of (...) superposition principle at unprecedented cosmological scales. (shrink)

This proposes a new theory of Quantum measurement; a state reduction theory in which reduction is to the elements of the number operator basis of a system, triggered by the occurrence of annihilation or creation (or lowering or raising) operators in the time evolution of a system. It is from these operator types that the acronym ‘LARC’ is derived. Reduction does not occur immediately after the trigger event; it occurs at some later time with probability P (...) t per unit time, where P t is very small. Localisation of macroscopic objects occurs in the natural way: photons from an illumination field are reflected off a body and later absorbed by another body. Each possible absorption of a photon by a molecule in the second body generates annihilation and raising operators, which in turn trigger a probability per unit time P t of a state reduction into the number operator basis for the photon field and the number operator basis of the electron orbitals of the molecule. Since all photons in the illumination field have come from the location of the first body, wherever that is, a single reduction leads to a reduction of the position state of the first body relative to the second, with a total probability of mP t , where m is the number of photon absorption events. Unusually for a reduction theory, the larc theory is naturally relativistic. (shrink)

This paper argues that the case for “gravitizing” quantum theory is at least as strong as that for quantizing gravity. Accordingly, the principles of general relativity must influence, and actually change, the very formalism of quantum mechanics. Most particularly, an “Einsteinian”, rather than a “Newtonian” treatment of the gravitational field should be adopted, in a quantum system, in order that the principle of equivalence be fully respected. This leads to an expectation that quantum superpositions of states involving a significant mass (...) displacement should have a finite lifetime, in accordance with a proposal previously put forward by Diósi and the author. (shrink)

There is a consistent and simple interpretation of the quantum theory of isolated systems. The interpretation suffers no measurement problem and provides a quantum explanation of state reduction, which is usually postulated. Quantum entanglement plays an essential role in the construction of the interpretation.

The paper contains a discussion on two kinds of coincidence experiments. First, a standard two-photon coincidence experiment is considered and it is shown that its outcomes are incompatible with any classical radiation theory because of the role of the state vector reduction phenomenon in such an experiment. In the second part of the paper a proposed new kind of photon coincidence experiment is discussed. The classical and quantum predictions for the outcomes of this experiment differ dramatically and therefore (...) the experiment should constitute a new limitation to the classical radiation theories. The proposed experiment should also yield information about the kinematics of the reduction of the state vector process. (shrink)

The usual distinction in quantum mechanics between pure states and mixtures is shown not to be independent of the interpretation adopted. Thus, in a causal theory, certain states should be regarded as sharing the nature of both pure states and mixtures and, as a result, important questions in the theory of measurement must be considered in a different light.

The relationship whereby one physical theory encompasses the domain of empirical validity of another is widely known as “reduction.” Elsewhere I have argued that one influential methodology for showing that one physical theory reduces to another, associated with the so-called “Bronstein cube” of theories, rests on an oversimplified and excessively vague characterization of the mathematical relationship between theories that typically underpins reduction. I offer what I claim is a more precise characterization of this relationship, which here is based (...) on a more basic notion of reduction between distinct models of a single physical system. Reduction between two such models, I claim, rests on a particular type of approximation relationship between group actions over the models’ state spaces, characterized by a particular function between the model state spaces and a particular subset of the more encompassing model’s state space. Within this approach, I show formally in what sense and under what conditions reduction is transitive, so that reduction of a model 1 to another model 2 and reduction of model 2 to a third model 3 entails direct reduction of model 1 to model 3. Building on this analysis, I consider cases in which reduction of a model 1 to a model 3 may be effected via distinct intermediate models 2a and 2b, and motivate a set of formal consistency requirements between distinct “reduction paths” having the same models as their “end points”. These constraints are explicitly shown to hold in the reduction of a model of non-relativistic classical mechanics to a model of relativistic quantum mechanics, which may be effected by a composite reduction that proceeds either via a model of non-relativistic quantum mechanics or a model of relativistic classical mechanics. I offer some brief speculations as to whether and how this sort of consistency requirement might serve to constrain the reductions relating other theories and models, including the relationship that the Standard Model and general relativity must bear to any viable unification of these frameworks. (shrink)

A common moral imperative to reduce human suffering in developing countries has helped to bring the international poverty reduction and conflict mitigation agendas together. But while research and practice are well established in the fields of poverty and conflict, the nexus between these two fields at the theoretical and practical levels is largely nascent. Lack of a shared body of knowledge has arguably impeded the ability of these communities to work together toward the overlapping goals of reducing poverty and (...) conflict in countries affected by violence and instability. Business, as a key sector of the international community, could potentially make significant contributions to the joint agenda if it were better integrated in efforts to develop the nexus. This article surveys the current states-of-knowledge in the fields of poverty and conflict, including the increasing influence of the fragile states theory. It then discusses some of the major schools of thought helping to bring poverty reduction efforts into alliance with conflict mitigation efforts. The third section identifies important conceptual convergences and divergences between the fields and reconsiders the prominent assumption that economic opportunity can be a powerful incentive for peace and stability. Finally, this article discusses potential areas that could advance the nexus of poverty and conflict at both a theoretical and practical level. (shrink)

A prominent view of phenomenal consciousness combines two claims: (i) the identity conditions of phenomenally conscious states can be fully accounted for in terms of these states’ representational content; (ii) this representational content can be fully accounted for in non-phenomenal terms. This paper presents an argument against this view. The core idea is that the identity conditions of phenomenally conscious states are not fixed entirely by what these states represent (their representational contents), but depend in part on how they represent (...) (their representational attitudes or modes). The argument highlights the myriad liabilities and difficulties one must accrue when one tries to appeal only to what phenomenally conscious states represent in accounting for their phenomenal individuation. (shrink)

In this paper I discuss the claim that the successful reduction of qualitative to physical states requires some sort of intelligible connection between our qualitative and physical concepts, which in turn requires a conceptual analysis of our qualitative concepts in causal-functional terms. While I defend this claim against some of its recent critics, I ultimately dispute it, and propose a different way to get the requisite intelligible connection between qualitative and physical concepts.

It is argued by means of analogy with certain irreversible processes that a symmetry-violating vacuum need not necessarily be explained by a special cosmic initial condition.

A central task of philosophy of mind in recent decades has been to come up with a comprehensive account of the mind that is consistent with materialism. To this end, philosophers have offered useful reductive accounts of mentality in terms that are ultimately explainable by neurobiology. Although these accounts have been useful for explaining some psychological states, one feature—phenomenality or consciousness—has proven to be particularly intractable. The Higher-Order Thought theory (HOT) has been offered as one reductive theory of consciousness. According (...) to HOT, a mental state is conscious if it becomes the content of a suitable higher-order thought that one is in that mental state. In recent years, critics have lodged a series of challenging objections to the view and several alternative theories have been proposed in response to these objections. This paper offers a defense of the traditional Higher-Order Thought theory. First, two different models of consciousness based on HOT are distinguished. The paper argues that one of the models is better supported by the HOT literature. It is then demonstrated that the better supported model is not vulnerable to the objections most commonly lodged against the HOT theory. Finally, it is shown that alternative self-representational theories do not improve upon the HOT theory in the way that they are proposed to. In fact, each of the alternative self-representational views reviewed here is vulnerable to a unique set of problems. In light of these factors, HOT still offers a viable reductive solution to the hard problem. (shrink)

It has been argued that most truths about macroscopic states of affairs are entailed by a (hypothetical) complete descriptionPof the world in microscopic terms. In principle, micro-reductive explanations of non-microphysical truths could be constructeda priori.Against this claim, I show that reductive explanation requires knowledge about the phenomena to be reduced which cannot bea prioriextracted from microphysical information alone. Such reductions proceed in two steps: a “reductionR0” (“role-occupant”) establishes that a macroproperty M plays a certain causal role (specified in macro-terms), while (...) a “reductionMM” (“micro-macro”) establishes that some microproperty gives rise toM. (shrink)

The past two decades have seen an explosion in the methods and directions of neuroscience research. Along with many others, complexity research has rapidly gained traction as both an independent research field and a valuable subdiscipline in computational neuroscience. In the past decade alone, several studies have suggested that psychiatric disorders affect the spatiotemporal complexity of both global and region-specific brain activity (Liu et al., 2013; Adhikari et al., 2017; Li et al., 2018). However, many of these studies have not (...) accounted for the distributed nature of cognition in either the global or regional complexity estimates, which may lead to erroneous interpretations of both global and region-specific entropy estimates. To alleviate this concern, we propose a novel method for estimating complexity. This method relies upon projecting dynamic functional connectivity into a low-dimensional space which captures the distributed nature of brain activity. Dimension-specific entropy may be estimated within this space, which in turn allows for a rapid estimate of global signal complexity. Testing this method on a recently acquired obsessive-compulsive disorder dataset reveals substantial increases in the complexity of both global and dimension-specific activity versus healthy controls, suggesting that obsessive-compulsive patients may experience increased disorder in cognition. To probe the potential causes of this alteration, we estimate subject-level effective connectivity via a Hopf oscillator-based model dynamic model, the results of which suggest that obsessive-compulsive patients may experience abnormally high connectivity across a broad network in the cortex. These findings are broadly in line with results from previous studies, suggesting that this method is both robust and sensitive to group-level complexity alterations. (shrink)

I argue that an adequate account of non-reductive realization must guarantee satisfaction of a certain condition on the token causal powers associated with (instances of) realized and realizing entities---namely, what I call the 'Subset Condition on Causal Powers' (first introduced in Wilson 1999). In terms of states, the condition requires that the token powers had by a realized state on a given occasion be a proper subset of the token powers had by the state that realizes it on (...) that occasion. Accounts of non-reductive realization conforming to this condition are implementing what I call 'the powers-based subset strategy'. I focus on the crucial case involving mental and brain states; the results may be generalized, as appropriate. I first situate and motivate the strategy by attention to the problem of mental causation; I make the case, in schematic terms, that implementation of the strategy makes room (contra Kim 1989, 1993, 1998, and elsewhere) for mental states to be ontologically and causally autonomous from their realizing physical states, without inducing problematic causal overdetermination, and compatible with both Physicalism and Non-reduction; and I show that several contemporary accounts of non-reductive realization (in terms of functional realization, parthood, and the determinable/determinate relation) are plausibly seen as implementing the strategy. As I also show, implementation of the powers-based strategy does not require endorsement of any particular accounts of either properties or causation---indeed, a categoricalist contingentist Humean can implement the strategy. The schematic location of the strategy in the space of available responses to the problem of mental (more generally, higher-level) causation, as well as the fact that the schema may be metaphysically instantiated, strongly suggests that the strategy is, appropriately generalized and instantiated, sufficient and moreover necessary for non-reductive realization. I go on to defend the sufficiency and necessity claims against a variety of objections, considering, along the way, how the powers-based subset strategy fares against competing accounts of purportedly non-reductive realization in terms of supervenience, token identity, and constitution. (shrink)

We apply the distinction between parameter independence and outcome independence to the linear and nonlinear models of a recent nonrelativistic theory of continuous state vector reduction. We show that in the nonlinear model there is a set of realizations of the stochastic process that drives the state vector reduction for which parameter independence is violated for parallel spin components in the EPR-Bohm setup. Such a set has an appreciable probability of occurrence (≈ 1/2). On the other (...) hand, the linear model exhibits only extremely small parameter dependence effects. We investigate some specific features of the models and we recall that, as has been pointed out recently, if one wants to be able to speak of definite outcomes (or equivalently of possessed objective elements of reality) at finite times, one has to slightly change the criteria for their attribution to physical systems. The concluding section is devoted to a detailed discussion of the difficulties which one meets when one tries to take, as a starting point for the formulation of a relativistic theory, a nonrelativistic scheme which exhibits parameter dependence. Here we derive a theorem which identifies the precise sense in which the occurrence of parameter dependence forbids a genuinely relativistic generalization. Finally we show how the appreciable parameter dependence of the nonlinear model gives rise to problems with relativity, while the extremely weak parameter dependence of the linear model does not give rise to any difficulty, provided one takes into account the appropriate criteria for the attribution of definite outcomes. (shrink)

Some claim that Non- reductive Physicalism is an unstable position, on grounds that NRP either collapses into reductive physicalism, or expands into emergentism of a robust or ‘strong’ variety. I argue that this claim is unfounded, by attention to the notion of a degree of freedom—roughly, an independent parameter needed to characterize an entity as being in a state functionally relevant to its law-governed properties and behavior. I start by distinguishing three relations that may hold between the degrees of (...) freedom needed to characterize certain special science entities, and those needed to characterize their composing physical entities; these correspond to what I call ‘reductions’, ‘restrictions’, and ‘eliminations’ in degrees of freedom. I then argue that eliminations in degrees of freedom, in particular—when strictly fewer degrees of freedom are required to characterize certain special science entities than are required to characterize their composing physical entities—provide a basis for making sense of how certain special science entities can be both physically acceptable and ontologically irreducible to physical entities. (shrink)

In this paper I discuss the claim (advanced in various ways by Joseph Levine, Frank Jackson and David Chalmers) that the successful reduction of qualitative to physical states requires some sort of intelligible connection between our qualitative and physical concepts, which in turn requires a conceptual analysis of our qualitative concepts in causal‐functional terms. While I defend this claim against some of its recent critics, I ultimately dispute it, and propose a different way to get the requisite intelligible connection (...) between qualitative and physical concepts. (shrink)

Most philosophical accounts of emergence are incompatible with reduction. Most scientists regard a system property as emergent relative to properties of the system's parts if it depends upon their mode of organization--a view consistent with reduction. Emergence can be analyzed as a failure of aggregativity--a state in which "the whole is nothing more than the sum of its parts." Aggregativity requires four conditions, giving tools for analyzing modes of organization. Differently met for different decompositions of the system, (...) and in different degrees, these conditions provide powerful evaluation criteria for choosing decompositions, and heuristics for detecting biases of vulgar reductionisms. This analysis of emergence is compatible with reduction. (shrink)

Husserl claimed that reduction is the true starting point of phenomenological research, but to figure out how this deed should actually be accomplished has turned out to be a very challenging task. In this study, I explicate how Husserl accomplished reduction during his series of lectures entitled The Idea of Phenomenology. He does not state it explicitly, but what actually happened on the last day of the lectures can be seen as consistent with his descriptions of (...) class='Hi'>reduction as an act. Understood in this way, reduction is the model of how to do philosophy. The result of Husserl’s reduction is the correlation between appearance and “that which appears” or, to use Husserl’s later terminology, between noēsis and noēma. When this correlation is understood as an outcome of reduction and not as a result of an analysis, we, as readers of Husserl, will be in a better position to avoid natural attitude in our interpretations. (shrink)

University Abstract Philosophers have sought to improve upon the logical empiricists’ model of scientific reduction. While opportunities for integration between the cognitive and the neural sciences have increased, most philosophers, appealing to the multiple realizability of mental states and the irreducibility of consciousness, object to psychoneural reduction. New Wave reductionists offer a continuum of comparative goodness of intertheoretic mapping for assessing reductions. Their insistence on a unified view of intertheoretic relations obscures epistemically significant crossscientific relations and engenders dismissive (...) conclusions about psychology. Richer, more sensitive accounts of explanatory pluralism and mechanistic explanation in science advocate multi-level approaches in cross-scientific settings and criticize the distance of the standard philosophical objections from working scientists’ practices and discoveries. The Heuristic Identity Theory, a new, scientifically informed version of the psycho-physical identity theory, incorporates these insights, showing how multiple realizability is an argument for (not against) identities in science and why, therefore, consciousness is not irreducible. (shrink)

Child poverty reduction is one of the most important and urgent tasks that requires attention in most regions of the world, nations and Anambra state specifically. The population of impoverished children is progressively increasing in Nigeria because of economic recession and poor security situations that lead to displacement and death of their parents. Although children constitute half of the entire population, commensurate attention is not given to them to match the dimensions of poverty they face. This study argued (...) that child poverty is multidimensional, evidenced in lack of safe drinking water, adequate nutrition, shelter, decent sanitation, medical advice or health services and education, to mention a few. The article highlighted the laudable efforts of the United Nations International Children’s Emergency Fund and Anambra government and maintained that multiple strategies can help in solving this problem. To complement these efforts, the enforcement of biblical policies or principles about children’s rights would in no small measure reduce child poverty. It was concluded that a proper repositioning of children would be matched with implementation of biblical strategies. Biblical intervention could help children socially, mentally and psychologically and in their general well-being. Biblical principles would erase wrong socio-cultural notions about children. (shrink)

Some claim that Non-reductive Physicalism is an unstable position, on grounds that NRP either collapses into reductive physicalism, or expands into emergentism of a robust or ‘strong’ variety. I argue that this claim is unfounded, by attention to the notion of a degree of freedom—roughly, an independent parameter needed to characterize an entity as being in a state functionally relevant to its law-governed properties and behavior. I start by distinguishing three relations that may hold between the degrees of freedom (...) needed to characterize certain special science entities, and those needed to characterize their composing physical entities; these correspond to what I call ‘reductions’, ‘restrictions’, and ‘eliminations’ in degrees of freedom. I then argue that eliminations in degrees of freedom, in particular—when strictly fewer degrees of freedom are required to characterize certain special science entities than are required to characterize their composing physical entities—provide a basis for making sense of how certain special science entities can be both physically acceptable and ontologically irreducible to physical entities. (shrink)

Scholars are divided as to whether reduction should be a central strategy for understanding the world. While reductive analysis is the standard mode of explanation in many areas of science and everyday life, many consider reductionism a sign of “intellectual naivete and backwardness.” In this paper I make three points about the proper status of anti-reductionism: First, reduction, is, in fact, a centrally important epistemic strategy. Second, reduction to physics is always possible for all causal properties. Third, (...) there are, nevertheless, reasons we want science to discover properties and explanations other than reductive physical ones. (shrink)

Symplectic reduction is a formal process through which degeneracy within the mathematical representations of physical systems displaying gauge symmetry can be controlled via the construction of a reduced phase space. Typically such reduced spaces provide us with a formalism for representing both instantaneous states and evolution uniquely and for this reason can be justifiably afforded the status of fun- damental dynamical arena - the otiose structure having been eliminated from the original phase space. Essential to the application of symplectic (...) reduction is the precept that the first class constraints are the relevant gauge generators. This prescription becomes highly problematic for reparameterization invariant theories within which the Hamiltonian itself is a constraint; not least because it would seem to render prima facie distinct stages of a history physically identical and observable functions changeless. Here we will consider this problem of time within non-relativistic me- chanical theory with a view to both more fully understanding the temporal struc- ture of these timeless theories and better appreciating the corresponding issues in relativistic mechanics. For the case of nonrelativistic reparameterization invariant theory application of symplectic reduction will be demonstrated to be both unnec- essary; since the degeneracy involved is benign; and inappropriate; since it leads to a trivial theory. With this anti-reductive position established we will then examine two rival methodologies for consistently representing change and observable func- tions within the original phase space before evaluating the relevant philosophical implications. We will conclude with a preview of the case against symplectic re- duction being applied to canonical general relativity. (shrink)

The use of a photomultiplier to measure the reduction in counting statistics noise (from the usual N1/2 form) which is expected to occur for squeezed coherent light is shown to lead to no reduction or to an increase of the noise unless the number of photons in a fundamental measuring time of the photomultiplier is very large. This fundamental time is estimated to be less than 10−13 sec for ordinary detectors. A technique for using squeezed states for determining (...) the time a photomultiplier takes to detect the presence of a photon is presented. (shrink)