Wavefunction collapse models modify Schrödinger's equation so that it describes the rapid evolution of a superposition of macroscopically distinguishable states to one of them. This provides a phenomenological basis for a physical resolution to the so-called “measurement problem.” Such models have experimentally testable differences from standard quantum theory. The most well developed such model at present is the Continuous Spontaneous Localization (CSL) model in which a universal fluctuating classical field interacts with particles to cause collapse. One “side (...) effect” of this interaction is that the field imparts energy to the particles: experimental evidence on this has led to restrictions on the parameters of the model, suggesting that the coupling of the classical field to the particles must be mass-proportional. Another “side effect” is that the field imparts momentum to particles, causing a small blob of matter to undergo random walk. Here we explore this in order to supply predictions which could be experimentally tested. We examine the translational diffusion of a sphere and a disc, and the rotational diffusion of a disc, according to CSL. For example, we find that the rms distance an isolated 10−5 cm radius sphere diffuses is ≈(its diameter, 5 cm) in (20 sec, a day), and that a disc of radius 2 ⋅ 10−5 cm and thickness 0.5 ⋅ 10−5 cm diffuses through 2πrad in about 70 sec (this assumes the “standard” CSL parameter values). The comparable rms diffusions of standard quantum theory are smaller than these by a factor 10−3±1. It is shown that the CSL diffusion in air at STP is much reduced and, indeed, is swamped by the ordinary Brownian motion. It is also shown that the sphere's diffusion in a thermal radiation bath at room temperature is comparable to the CSL diffusion, but is utterly negligible at liquid He temperature. Thus, in order to observe CSL diffusion, the pressure and temperature must be low. At the low reported pressure of 5 ⋅ 10−17 Torr, achieved at 4.2°K, the mean time between air molecule collisions with the (sphere, disc) is ≈(80, 45)min. This is ample time for observation of the putative CSL diffusion with the standard parameters and, it is pointed out, with any parameters in the range over which the theory may be considered viable. This encourages consideration of how such an experiment may actually be performed, and the paper closes with some thoughts on this subject. (shrink)

It is emphasized that the collapse postulate of standard quantum theory can violate conservation of energy-momentum and there is no indication from where the energy-momentum comes or to where it goes. Likewise, in the Continuous Spontaneous Localization (CSL) dynamical collapse model, particles gain energy on average. In CSL, the usual Schrödinger dynamics is altered so that a randomly fluctuating classical field interacts with quantized particles to cause wavefunction collapse. In this paper it is shown how to (...) define energy for the classical field so that the average value of the energy of the field plus the quantum system is conserved for the ensemble of collapsing wavefunctions. While conservation of just the first moment of energy is, of course, much less than complete conservation of energy, this does support the idea that the field could provide the conservation law balance when events occur. (shrink)

The answer may be yes. A discrete model of energy-conserved wavefunction collapse is proposed. It is shown that the model is consistent with existing experiments and our macroscopic experience.

We give a new argument supporting a gravitational role in quantum collapse. It is demonstrated that the discreteness of space-time, which results from the proper combination of quantum theory and general relativity, may inevitably result in the dynamical collapse of thewave function. Moreover, the minimum size of discrete space-time yields a plausible collapse criterion consistent with experiments. By assuming that the source to collapse the wave function is the inherent random motion of particles described by the (...) wave function, we further propose a concrete model of wavefunction collapse in the discrete space-time. It is shown that the model is consistent with the existing experiments and macroscopic experiences. (shrink)

Peter Lewis ([1997]) has recently argued that the wavefunction collapse theory of GRW (Ghirardi, Rimini and Weber [1986]) can only solve the problem of wavefunction tails at the expense of predicting that arithmetic does not apply to ordinary macroscopic objects. More specifically, Lewis argues that the GRW theory must violate the enumeration principle: that 'if marble 1 is in the box and marble 2 is in the box and so on through marble n, then all n marbles (...) are in the box' ([1997], p. 321). Ghirardi and Bassi ([1999]) have replied that it is meaningless to say that the enumeration principle is violated because the wavefunction Lewis uses to exhibit the violation cannot persist, according to the GRW theory, for more than a split second ([1999], p. 709). On the contrary, we argue that Lewis's argument survives Ghirardi and Bassi' s criticism unscathed. We then go on to show that, while the enumeration principle can fail in the GRW theory, the theory itself guarantees that the principle can never be empirically falsified, leaving the applicability of arithmetical reasoning to both micro- and macroscopic objects intact. (shrink)

Two versions of the GRW “hitting” model for explicit wavefunction collapse, which are consistent with preserving the symmetry of the wavefunction, are considered. The predictions of the models for excitation of bound systems are calculated and compared with experiment and with the predictions of other similar models. It is shown that our preferred model strongly supports the idea that collapse, if it occurs, has gravitational origin.

According to Penrose, the fundamental conflict between the superposition principle of quantum mechanics and the principle of general covariance of general relativity entails the existence of wavefunction collapse, e.g. a quantum superposition of two different space–time geometries will collapse to one of them due to the ill-definedness of the time-translation operator for the superposition. In this paper, we argue that Penrose's conjecture on gravity's role in wavefunction collapse is debatable. First of all, it is still (...) a controversial issue what the exact nature of the conflict is and how to resolve it. Secondly, Penrose's argument by analogy is too weak to establish a necessary connection between wavefunction collapse and the conflict as understood by him. Thirdly, the conflict does not necessarily lead to wavefunction collapse. The reason is that the conflict or the problem of ill-definedness for a superposition of different space–time geometries also needs to be solved before the collapse of the superposition finishes, and once the conflict has been resolved, the wavefunction collapse will lose its physical basis relating to the conflict. In addition, we argue that Penrose's suggestions for the collapse time formula and the preferred basis are also problematic. (shrink)

Examining the notion of wavefunction collapse (WFC) in quantum measurements, which came again to be in question in the recent debate on the quantum Zeno effect, we remark that WFC is realized only through decoherence among branch waves by detection, after a spectral decomposition process from an initial object wavefunction to a superposition of branch waves corresponding to relevant measurement propositions. We improve the definition of the decoherence parameter, so as to be fitted to general cases, by (...) which we can quantitatively estimate the degree of WFC given by detectors. Finally, we briefly discuss whether two special detector models, with very huge and very small degrees of freedom, can provoke WFC. (shrink)

It is shown that data on the dissociation rate of deuterium obtained in an experiment at the Sudbury Neutrino Observatory provides evidence that the Continuous Spontaneous Localization wavefunction collapse model should have mass–proportional coupling to be viable.

According to Penrose, the fundamental conflict between the superposition principle of quantum mechanics and the general covariance principle of general relativity entails the existence of wavefunction collapse, e.g. a quantum superposition of two different space-time geometries will collapse to one of them due to the ill-definedness of the time-translation operator for the superposition. In this paper, we argue that Penrose's conjecture on gravity's role in wavefunction collapse is debatable. First of all, it is still a (...) controversial issue what the exact nature of the conflict is and how to resolve it. Secondly, Penrose's argument by analogy is too weak to establish a necessary connection between wavefunction collapse and the conflict as understood by him. Thirdly, the conflict does not necessarily lead to wavefunction collapse. For the conflict or the problem of ill-definedness for a superposition of different space-time geometries also needs to be solved before the collapse of the superposition finishes, and once the conflict has been resolved, the wavefunction collapse will lose its physical basis relating to the conflict. In addition, we argue that Penrose's suggestions for the collapse time formula and collapse states are also problematic. (shrink)

Lewis 313) has recently presented an argument claiming that, under the Ghirardi–Rimini–Weber theory of quantum mechanics, arithmetic does not apply to ordinary macroscopic objects such as marbles . In this paper, I disentangle two different lines of Lewis's argument, one devoted to what I call the standard GRW interpretation and the other to the mass density interpretation . I present both strains of Lewis's argument, and move on to criticise Lewis's position, focusing on his argument with respect to MDI. I (...) analyse the structure of his argument, and follow this with a novel refutation of Lewis's argument, drawing on the original presentation of MDI as developed by Ghirardi et al. 5). I briefly consider the debate that ensued between Bassi and Ghirardi and Clifton and Monton and interpret it within the context of my analysis. I conclude that Lewis's Counting Anomaly fails to generate a genuine problem. (shrink)

Energy nonconservation is a serious problem of dynamical collapse theories. In this paper, we propose a discrete model of energy-conserved wavefunction collapse. It is shown that the model is consistent with existing experiments and our macroscopic experience.

A two-body quantum correlation is calculated for a particle reflecting from a moving mirror. Correlated interference results when the incident and reflected particle substates and their associated mirror substates overlap. Using the Copenhagen interpretation of measurement, an asynchronous joint probability density, which is a function both of the different positions and different times at which the particle and mirror are measured, is derived assuming that no interaction occurs between each measurement. Measurement of the particle first, in the correlated interference region, (...) results in a splitting of the mirror substate into ones which have and have not reflected the particle. An analog of the interference from the Doppler effect for only measurements of the particle, in this two-body system, is shown to be a consequence of the asynchronous measurement. The simplification obtained for a microscopic particle reflecting from a mesoscopic or macroscopic mirror is used to illustrate asynchronous correlation interferometry. In this case, the small displacement between these mirror states can yield negligible environmental decoherence times. In addition, interference of these mirror states does not vanish in the limit of large mirror mass due to the small momentum exchange in reflecting a microscopic particle. (shrink)

The perplexing relationship between consciousness and quantum mechanics remains one of science's greatest enigmas. The "wavefunction collapse" phenomenon, where a quantum system's superposition of possibilities resolves into a single definite state upon measurement, has ignited heated debates about the role of consciousness in shaping reality. This article delves into the heart of this "quantum quagmire," exploring various interpretations of wavefunction collapse and their implications for the nature of consciousness and the observer-observed relationship.

The holistic view of the Universe is a very promising approach. The necessity of such a view is shown by the teaching of Carl Friedrich von Weizsäcker, a German physicist and philosopher. If we accept Panpsychism as the best alternative to Materialism and Dualism, we should take the holistic view seriously. Panpsychism and Holism combined lead to the Idea of Cosmopsychism. If we consider the Universe as a holistic Quantum System, we should ask, what causes the collapse of its (...) wavefunction? I offer four possible answers and I tend to divine consciousness, which brings the collapse of the wavefunction of our Universe. (shrink)

A common understanding of both the many-worlds theory and the original version of the GRW theory holds that they are ontologically monistic, postulating only the existence of the wavefunction and nothing else. Sometimes an appeal to Occam's razor is used to promote this as a boon for these theories. But without more detailed argumentation, it is hard to see how such an austere ontology can make comprehensible contact with the experimental facts that inspired the development of quantum theory in (...) the first place, or indeed with our whole pre-theoretical picture of the physical world. (shrink)

The collapse of the wavefunction is arguably the least understood process in quantum mechanics. A plethora of ideas—macro-micro divide, many worlds and even consciousness—have been put forth to resolve the issue. Contrary to the standard Copenhagen interpretation, objective collapse models modify the Schrödinger equation with nonlinear and stochastic terms in order to explain the collapse of the wavefunction. In this paper we propose a collapse model in which a particle’s wavefunction has a possibility (...) of collapsing when it interacts with macroscopic objects, without the intervention of a conscious observer. We propose four possible conditions of collapse of the wavefunction and make testable predictions which differ from standard quantum mechanics. (shrink)

I present and explain the Bohmian account of collapse in quantum mechanics.

The measurement problem concerns an apparent conflict between the two fundamental principles of quantum mechanics, namely the Schrödinger equation and the measurement postulate. These principles describe inconsistent behavior for quantum systems in so-called "measurement contexts." Many theorists have thought that the measurement problem can only be resolved by proposing a mechanistic explanation of (genuine or apparent) wavefunction collapse that avoids explicit reference to "measurement." However, I argue here that the measurement problem dissolves if we accept Humeanism about laws (...) of nature. On a Humean metaphysics, there is no conflict between the two principles, nor is there any inherent problem with the concept of "measurement" figuring into the account of collapse. (shrink)

In Sect. 10.1007/978-3-319-78356-7_2, the measurement problem was formulated in the form of aMaudlin trilemma trilemma. In this view, either (i) the wavefunction is not a complete description; or (ii) the time evolution is not a continuous unitary process; or (iii) measurements do not lead to well-defined results. The GRW theory described in Sect. 10.1007/978-3-319-78356-7_2 chooses alternative (ii); it adds a nonlinear term to the Schrödinger equation, which models a physical mechanism for the “actual” collapse of the wavefunction. (...) The Copenhagen interpretation also denies a continuous time evolution which follows the Schrödinger equation; in contrast to the GRW theory, this process is however not given a realistic interpretation. (shrink)

Spontaneous collapse models are modifications of standard quantum mechanics in which a physical mechanism is responsible for the collapse of the wavefunction, thus providing a way to solve the so-called “measurement problem”. The two most famous of these models are the Ghirardi–Rimini–Weber (GRW) model and the Continuous Spontaneous Localisation (CSL) models. Here, we propose a new kind of non-relativistic spontaneous collapse model based on the idea of collapse points situated at fixed spacetime coordinates. This model (...) shares properties of both GRW and CSL models, while starting from different assumptions. We show that it can lead to a dynamics quite similar to that of the GRW model while also naturally solving the problem of indistinguishable particles. On the other hand, we can also obtain the same master equation of the CSL models. Then, we show how our proposed model solves the measurement problem in a manner conceptually similar to the GRW model. Finally, we show how the proposed model can also accommodate for Newtonian gravity by treating the collapses as gravitational sources. (shrink)

A brief review is given of the continuous spontaneous localization (CSL) model, in which a classical field interacts with quantized particles to cause dynamical wavefunction collapse. One of the model's predictions is that particles “spontaneously” gain energy at a slow rate. When applied to the excitation of a nucleon in a Ge nucleus, it is shown how a limit on the relative collapse rates of neutron and proton can be obtained, and a rough estimate is made from (...) data. When applied to the spontaneous excitation of 1s electrons in Ge, by a more detailed analysis of more accurate data than given previously, an updated limit is obtained on the relative collapse rates of the electron and proton, suggesting that the coupling of the field to electrons and nucleons is mass proportional. (shrink)

This paper introduces the formal framework of Improbabilistic Logic — a phase-anchored and non-sequential logic that rejects the ontological validity of both past and future events. Grounded in the idea that temporally referenced acts are fictive, this logic proposes that truth emerges not from probabilistic inference or modal necessity, but from present-moment coherence. The core contribution is the definition of a novel operator Λˆ, which selects epistemic states by measuring their phase alignment with the observer. In contrast to classical logics (...) based on temporal succession and statistical likelihood, Improbabilistic Logic reframes logical validity as a resonance condition internal to the act of knowing. It reformulates logical operators in terms of phase-congruent actualization and establishes coherence as the fundamental structure of epistemic presence. We further explore the implications of this framework for quantum measurement theory, temporal ontology, and models of cognitive instability. The collapse of the wavefunction is reinterpreted as a resolution of phase ambiguity, while phenomena such as black hole information paradoxes and polymorphic psychoses are discussed as manifestations of phase-disruption in cognitive systems. By replacing sequential temporality with ontological alignment, Im-probabilistic Logic offers a new paradigm for both physics and philosophy — one in which time, probability and cognition are unified under the principle of present-phase coherence. (shrink)

This work introduces a novel model of quantum entities as unified, physically extended wavefields, forming the basis for a testable realist, holist framework for quantum measurement and collapse. Unlike interpretations that postulate hidden variables, observer-induced effects, spontaneous stochastic collapse, or multiverse branching, this model derives the Born rule from the squared-amplitude structure of an extended wavefield undergoing localized, interaction-induced collapse. Central to the model is a reinterpretation of the Heisenberg uncertainty principle—not merely as a statistical or epistemic (...) limitation, but as a dynamical relation between localized energetic interaction and wavefield localization. This framework yields testable predictions about how weak, intermediate, and strong quantum interactions modulate spatial localization—predictions consistent with existing experimental findings. The upshot is a unified, falsifiable alternative to standard interpretations, and a foundation for a broader research program in wavefield interaction mechanics. (shrink)

The meaning of the wave function and its evolution are investigated. First, we argue that the wave function in quantum mechanics is a description of random discontinuous motion of particles, and the modulus square of the wave function gives the probability density of the particles being in certain locations in space. Next, we show that the linear non-relativistic evolution of the wave function of an isolated system obeys the free Schrödinger equation due to the requirements of spacetime translation invariance and (...) relativistic invariance. Thirdly, we argue that the random discontinuous motion of particles may lead to a stochastic, nonlinear collapse evolution of the wave function. A discrete model of energy-conserved wavefunction collapse is proposed and shown consistent with existing experiments and our macroscopic experience. Besides, we also give a critical analysis of the de Broglie-Bohm theory, the many-worlds interpretation and other dynamical collapse theories, and briefly discuss the issues of unifying quantum mechanics and relativity. (shrink)

This paper presents a new modified quantum mechanics, Critical Complexity Quantum Mechanics, which includes a new account of wavefunction collapse. This modified quantum mechanics is shown to arise naturally from a fully discrete physics, where all physical quantities are discrete rather than continuous. I compare this theory with the spontaneous collapse theories of Ghirardi, Rimini, Weber and Pearle and discuss some implications of these theories and CCQM for a realist view of the quantum realm.

A sophisticated and original introduction to the philosophy of quantum mechanics from one of the world’s leading philosophers of physics In this book, Tim Maudlin, one of the world’s leading philosophers of physics, offers a sophisticated, original introduction to the philosophy of quantum mechanics. The briefest, clearest, and most refined account of his influential approach to the subject, the book will be invaluable to all students of philosophy and physics. Quantum mechanics holds a unique place in the history of physics. (...) It has produced the most accurate predictions of any scientific theory, but, more astonishing, there has never been any agreement about what the theory implies about physical reality. Maudlin argues that the very term “quantum theory” is a misnomer. A proper physical theory should clearly describe what is there and what it does—yet standard textbooks present quantum mechanics as a predictive recipe in search of a physical theory. In contrast, Maudlin explores three proper theories that recover the quantum predictions: the indeterministic wavefunction collapse theory of Ghirardi, Rimini, and Weber; the deterministic particle theory of deBroglie and Bohm; and the conceptually challenging Many Worlds theory of Everett. Each offers a radically different proposal for the nature of physical reality, but Maudlin shows that none of them are what they are generally taken to be. (shrink)

In [1] it is claimed that, based on radiation emission measurements described in [2], a certain “variant” of the Orch OR theory has been refuted. I agree with this claim. However, the significance of this result for Orch OR per se is unclear. After all, the refuted “variant” was never advocated by anyone, and it contradicts the views of Hameroff and Penrose (hereafter: HP) who invented Orch OR [3]. My aim is to get clear on this situation. I argue that (...) it is indeed reasonable to speak of “variants” here. Orch OR is not a complete model of reality but a work in progress. At its core, it claims that wavefunction collapse is a real physical event that has something to do with gravity (“OR”) and that consciousness depends on orchestrated collapses in microtubules (“Orch”). There are many ways one could make these base ideas precise hence many “variants”. Furthermore, the ways that HP aim to make these ideas precise are radical and incomplete. If they don’t work out, Orch OR will need to fall back on another variant. Thus, I believe the significance of [1-2] for Orch OR is that it cuts out a small class of possible variants and leaves behind questions and challenges for the rest, including the variant preferred by HP. (shrink)

In a recent paper, Conway and Kochen proposed what is now known as the “Free Will theorem” which, among other things, should prove the impossibility of combining GRW models with special relativity, i.e., of formulating relativistically invariant models of spontaneous wavefunction collapse. Since their argument basically amounts to a non-locality proof for any theory aiming at reproducing quantum correlations, and since it was clear since very a long time that any relativistic collapse model must be non-local in (...) some way, we discuss why the theorem of Conway and Kochen does not affect the program of formulating relativistic GRW models. (shrink)

Now consider a Popperian-type conjecture on the time of an instant and the problem of motion, when setting the rational endeavour of modern physics, with a focus on Bohr’s complementarity, before the logical challenge of ancient paradox, specifically Zeno’s Flying Arrow, and so for demonstrating the philosophical power of reason over such combinatory reflection as thereby to yield novel scientific insight. By addressing the arrow argument precisely on its own logical terms, and by adaptively applying a core principle of quantum (...) mechanical theory, the study argues that the possibility of motion, from little atoms to large arrows, is contingent upon space and time acting as dynamical properties of forms in motion – and crucially, as such properties that possess both a quantitative and a qualitative character. The reasoning engages with the pertinent thought of influential philosophers, mathematicians and physicists, both past and present, hence drawing the ‘common science’ issue of an emphatic quantitative mindset into the identification of a Kantian-style antinomy of the pure quantum instant. The results show that certain core conundrums – like the measurement problem in quantum mechanics about the ‘collapse’ of the wavefunction, and that of quantum gravity, with so many conflicting conceptions of space, time and motion dividing the canonical, covariant and other approaches – must persist for so long as Zeno’s challenge is not formally answered with the philosophical grasp and scientific understanding of a fundamentally qualitative instant of motion. (shrink)

Modern physics is built on the assumption that time only moves one way, beginning at the initial boundary (or initial condition), fixed effectively at the Big Bang. Our theories begin at that starting point and evolve from there. Yet the laws of nature work both forward and backward. This one-way view lies at the root of many of physics’ biggest puzzles, like wavefunction collapse, quantum “spookiness,” the arrow of time, and the clash between quantum mechanics and relativity. Two-Boundary (...) Theory (2BT) proposes a minimal correction: the universe is a unique four-dimensional history jointly constrained by two real temporal boundaries, an initial (α) and a final (Ω). No new dynamics or hidden variables are added; the same lawful evolution operates in both directions, and the realized world is the intersection of the forward image of α with the backward image of Ω. From within time, partial knowledge of α and ignorance of Ω make outcomes appear stochastic and the future “open,” though the underlying history is globally deterministic and locally causal. This two-sided admissibility resolves the major paradoxes in a single move: Bell-level correlations arise from whole-trajectory consistency rather than superluminal influence; measurement collapse becomes an epistemic update, not a physical jump; and the arrow of time reflects asymmetric boundary information, not asymmetric law. The analysis preserves unitarity, covariance, and conservation principles intact. The paper confines itself to the conceptual and ontological core of the framework; later work develops the informational field Φ(t) and weighted-operator formalism that implement the same constraint mathematically. The result is an Ockham-minimal, time-symmetric completion of the scientific worldview: one reversible law, two boundaries, one consistent universe. (shrink)

Starting from difference as the sole ontological origin, this paper establishes a self-consistent and complete constructive theory of space in which relations, rather than entities or a pre-existing container, serve as the fundamental basis. Difference is isomorphic and synonymous with this-that; space is generated directly by the unfolding of this-that as a relational act, not merely described by relations within a ready-made arena. Three secondary spatial relations: up-down, left-right, inside-outside-are further derived within space. All physical phenomena, including quantum superposition, entanglement, (...) wavefunction collapse, and parity non-conservation, are superficial manifestations determined by these underlying spatial relations. This theory unifies the explanation of space and quantum phenomena and proposes four falsifiable, experimentally testable predictions. (shrink)

This thesis is an attempt to reconstruct the conceptual foundations of quantum mechanics. First, we argue that the wave function in quantum mechanics is a description of random discontinuous motion of particles, and the modulus square of the wave function gives the probability density of the particles being in certain locations in space. Next, we show that the linear non-relativistic evolution of the wave function of an isolated system obeys the free Schrödinger equation due to the requirements of spacetime translation (...) invariance and relativistic invariance. Thirdly, we argue that the random discontinuous motion of particles may lead to a stochastic, nonlinear collapse evolution of the wave function. A discrete model of energy-conserved wavefunction collapse is proposed and shown to be consistent with existing experiments and our macroscopic experience. In addition, we also give a critical analysis of the de Broglie-Bohm theory, the many-worlds interpretation and other dynamical collapse theories, and briefly discuss the issue of unifying quantum mechanics and special relativity. (shrink)

Many believe that quantum mechanics makes the world hospitable to the tensed theory of time. Quantum mechanics is said to rescue the significance of the present moment, the mutability of the future and possibly even the whoosh of time’s flow. It allegedly does so in two different ways: by making a preferred foliation of spacetime into space and time scientifically respectable, and by wavefunction collapse injecting temporal ‘becoming’ into the world. The aim of this paper is to show (...) that the reasoning underlying these claims is wishful thinking. Against the first claim I develop what I call the “coordination problem” for tensers. The upshot of this problem is that if tensers escape the threat of relativity, they do so only by embracing conflict with the branch of physics they believed saved them, quantum mechanics. I then step back from the fray and examine some methodological issues, concluding that scientific methodology will always be “against” tenses as they are currently conceived. The Appendix deals with the confused tangle of issues linking wavefunction collapse to an open future. (shrink)

This paper surveys some of the questions that arise when we consider how entanglement and relativity are related via the notion of non-locality. We begin by reviewing the role of entangled states in Bell inequality violation and question whether the associated notions of non-locality lead to problems with relativity. The use of entanglement and wavefunction collapse in Einstein's famous incompleteness argument is then considered, before we go on to see how the issue of non-locality is transformed if one (...) considers quantum mechanics without collapse to be a complete theory, as in the Everett interpretation. (shrink)

An adynamical 4D block universe governed by global constraint satisfaction functions as a complete Theory of Everything, because it subsumes all physical phenomena - from General Relativity to Quantum Mechanics - under a single, unified geometric principle without relying on separate, incompatible laws. Instead of positing dynamic forces or fundamental fields that drive events through time, it demonstrates that classical determinism, quantum wave behavior, non-local entanglement, cosmic symmetries and entropy are all emergent mathematical artifacts of a static 4D mosaic avoiding (...) internal contradictions. By resolving the conflict between smooth spacetime continuity and discrete quantum states as a pointillist illusion optimized for low structural friction, the framework eliminates the need for wavefunction collapse, hidden forces, or temporal causation, explaining not how the universe evolves, but why its complete structure fits together as a single, self-consistent reality. (shrink)

Q0 Why this FAQ? Q1 Who believes in many-worlds? Q2 What is many-worlds? Q3 What are the alternatives to many-worlds? Q4 What is a "world"? Q5 What is a measurement? Q6 Why do worlds split? What is decoherence? Q7 When do worlds split? Q8 When does Schrodinger's cat split? Q9 What is sum-over-histories? Q10 What is many-histories? What is the environment basis? Q11 How many worlds are there? Q12 Is many-worlds a local theory? Q13 Is many-worlds a deterministic theory? Q14 (...) Is many-worlds a relativistic theory? What about quantum field theory? What about quantum gravity? Q15 Where are the other worlds? Q16 Is many-worlds (just) an interpretation? Q17 Why don't worlds fuse, as well as split? Do splitting worlds imply irreversible physics? Q18 What retrodictions does many-worlds make? Q19 Do worlds differentiate or split? Q20 What is many-minds? Q21 Does many-worlds violate Ockham's Razor? Q22 Does many-worlds violate conservation of energy? Q23 How do probabilities emerge within many-worlds? Q24 Does many-worlds allow free-will? Q25 Why am I in this world and not another? Why does the universe appear random? Q26 Can wavefunctions collapse? Q27 Is physics linear? Could we ever communicate with the other worlds? Why do I only ever experience one world? Why am I not aware of the world (and myself) splitting? Q28 Can we determine what other worlds there are? Is the form of the Universal Wavefunction knowable? Q29 Who was Everett? Q30 What are the problems with quantum theory? Q31 What is the Copenhagen interpretation? Q32 Does the EPR experiment prohibit locality? What about Bell's Inequality? Q33 Is Everett's relative state formulation the same as many-worlds? Q34 What is a relative state? Q35 Was Everett a "splitter"? Q36 What unique predictions does many-worlds make? Q37 Could we detect other Everett-worlds? Q38 Why quantum gravity? Q39 Is linearity exact? (shrink)

In this chapter, I discuss time in nonrelativistic quantum theories. Within an instrumentalist theory like von Neumann’s axiomatic quantum mechanics, I focus on the meaning of time as an observable quantity, on the idea of time quantization, and whether the wavefunction collapse suggests that there is a preferred temporal direction. I explore this last issue within realist quantum theories as well, focusing on time reversal symmetry, and I analyze whether some theories are more hospitable for time travel than (...) others. (shrink)

We argue that it is fundamentally impossible to recover information about quantum superpositions when a quantum system has interacted with a sufficiently large number of degrees of freedom of the environment. This is due to the fact that gravity imposes fundamental limitations on how accurate measurements can be. This leads to the notion of undecidability: there is no way to tell, due to fundamental limitations, if a quantum system evolved unitarily or suffered wavefunction collapse. This in turn provides (...) a solution to the problem of outcomes in quantum measurement by providing a sharp criterion for defining when an event has taken place. We analyze in detail in examples two situations in which in principle one could recover information about quantum coherence: (a) “revivals” of coherence in the interaction of a system with the measurement apparatus and the environment and (b) the measurement of global observables of the system plus apparatus plus environment. We show in the examples that the fundamental limitations due to gravity and quantum mechanics in measurement prevent both revivals from occurring and the measurement of global observables. It can therefore be argued that the emerging picture provides a complete resolution to the measurement problem in quantum mechanics. (shrink)

A possible mechanism of nonlinear quantum evolution is introduced and its implications for quantum communication are investigated. First, it is demonstrated that an appropriate combination of wavefunction collapse and the consciousness of observer may permit the observer to distinguish nonorthogonal quantum states in principle, and thus consciousness will introduce certain nonlinearity into quantum dynamics. Next, it is shown that the distinguishability of nonorthogonal states can be used to achieve quantum superluminal communication, by which information can be transmitted nonlocally (...) and faster than the speed of light. Finally, the issue of apparent incompatibility between superluminal communication and special relativity is briefly addressed. (shrink)

This article examines how quantum theory—and the emerging landscape of quantum technologies—has reshaped contemporary aesthetic, narrative, and moral imagination. Moving beyond the well-documented influence of relativity on early modernist art, it argues that quantum mechanics has generated a particularly influential cultural provocation: superposition, entanglement, and probabilistic ontology have challenged classical assumptions about identity, causality, and worldhood. The essay traces how these concepts migrated into artistic practice long before their full technological realization. The discussion begins with Fernando Pessoa’s (1888–1935) heteronymy, read (...) as an early literary analogue of entanglement: a distributed authorship in which multiple selves coexist and condition one another without resolving into unity. It then turns to Raúl Ruiz’s _Three Lives and Only One Death_ (1996), whose overlapping destinies exemplify superposition at the level of cinematic ontology. A further step is taken with the Daniels’ interactive short _Possibilia_ (2014), where digital branching structures operationalize narrative choice as a form of wavefunction collapse. The article also considers the philosophical and moral resonance of _Everything Everywhere All at Once_ (2022), interpreted through an Everettian framework, and turns to Werner Herzog’s _Theatre of Thought_ (2022), which explores speculative links between quantum theory and consciousness. A subsequent section addresses the proliferation of “quantum woo,” examining how quantum terminology circulates within wellness cultures and tracing its unexpected historical ties to the countercultural physics of the 1970s and the emergence of the no-cloning theorem. In the conclusion, the essay offers an ekphrastic reading of Laure Prouvost’s _We Felt a Star Dying_ (2025), an installation that reframes quantum uncertainty and fragility as perceptual experience. Across these cases, the article sketches the contours of what might be called a ‘quantum humanism’, in which science and the arts collaborate to render the quantum world culturally intelligible without trivialization or mystification. (shrink)

We analyze the possible implications of spacetime discreteness for the special and general relativity and quantum theory. It is argued that the existence of a minimum size of spacetime may explain the invariance of the speed of light in special relativity and Einstein’s equivalence principle in general relativity. Moreover, the discreteness of spacetime may also result in the collapse of the wave function in quantum mechanics, which may provide a possible solution to the quantum measurement problem. These interesting results (...) might have some important implications for a complete theory of quantum gravity. (shrink)

This paper presents a new Symmetrical Interpretation (SI) of relativistic quantum mechanics which postulates: quantum mechanics is a theory about complete experiments, not particles; a complete experiment is maximally described by a complex transition amplitude density; and this transition amplitude density never collapses. This SI is compared to the Copenhagen Interpretation (CI) for the analysis of Einstein’s bubble experiment. This SI makes several experimentally testable predictions that differ from the CI, solves one part of the measurement problem, resolves some inconsistencies (...) of the CI, and gives intuitive explanations of some previously mysterious quantum effects. (shrink)

We argue that it is fundamentally impossible to recover information about quantum superpositions when a quantum system has interacted with a sufficiently large number of degrees of freedom of the environment. This is due to the fact that gravity imposes fundamental limitations on how accurate measurements can be. This leads to the notion of undecidability: there is no way to tell, due to fundamental limitations, if a quantum system evolved unitarily or suffered wavefunction collapse. This in turn provides (...) a solution to the problem of outcomes in quantum measurement by providing a sharp criterion for defining when an event has taken place. We analyze in detail in examples two situations in which in principle one could recover information about quantum coherence: a) “revivals” of coherence in the interaction of a system with the measurement apparatus and the environment and b) the measurement of global observables of the system plus apparatus plus environment. We show in the examples that the fundamental limitations due to gravity and quantum mechanics in measurement prevent both revivals from occurring and the measurement of global observables. It can therefore be argued that the emerging picture provides a complete resolution to the measurement problem in quantum mechanics. (shrink)

A case for the project of excising of confusion and obfuscation in the contemporary quantum theory initiated and promoted by David Deutsch has been made. It has been argued that at least some theoretical entities which are conventionally labelled as “interpretations” of quantum mechanics are in fact full-blooded physical theories in their own right, and as such are falsifiable, at least in principle. The most pertinent case is the one of the so-called “Many-Worlds Interpretation” (MWI) of Everett and others. This (...) set of idea differs from other “interpretations” since it does not accept reality of the collapse of Schrödinger’s wavefunction. A survey of several important proposals for discrimination between quantum theories with and without wavefunction collapse appearing from time to time in the literature has been made, and the possibilities discussed in the framework of a wider taxonomy. (shrink)

Collapse theories provide one of the main approaches to the quantum measurement problem. Roderich Tumulka’s collapse theory (GRWf) has attracted interest because it offers a relativistic collapse theory. GRWf utilises an ontology of flashes to accommodate EPR-Bell type non-local influences within a relativistic theory, an idea suggested by John Bell. Tim Maudlin raises a concern with Tumulka’s flash ontology, arguing that it is too sparse to convincingly account for certain microscopic phenomena. This paper proposes a modification to (...) GRWf that addresses the problem of sparseness, whilst retaining a relativistic treatment of quantum non-locality. The proposal, referred to as the space-time normalisation interpretation (STN), combines the GRWf flash ontology with a statistical interpretation of the wavefunction. The statistical structure of the interpretation is presented as a Hawkes process, consisting of flashes and an intensity function governing their occurrence. For a single-particle system, the square modulus of a renormalised wavefunction serves as the intensity function of the Hawkes process. (shrink)

The recent debates concerning divine action in the context of quantum mechanics are examined with particular reference to the work of William Pollard, Robert J. Russell, Thomas Tracy, Nancey Murphy, and Keith Ward. The concept of a quantum mechanical “event” is elucidated and shown to be at the center of this debate. An attempt is made to clarify the claims made by the protagonists of quantum mechanical divine action by considering the measurement process of quantum mechanics in detail. Four possibilities (...) for divine influence on quantum mechanics are identified and the theological and scientific implications of each discussed. The conclusion reached is that quantum mechanics is not easily reconciled with the doctrine of divine action. (shrink)

Quantum mechanics and consciousness often meet in attempts to explain subjective experience through the peculiar rules of the quantum world. Classical physics provides a tidy, deterministic universe, but quantum mechanics unsettles this picture: particles can be in multiple states simultaneously, measurements alter what is observed, and distant objects can remain linked in ways that defy common sense.This quantum strangeness has captivated researchers seeking to understand consciousness—that most puzzling feature of the mind which allows us to experience rather than merely process (...) information. If classical computation seems insufficient to capture the richness of conscious experience, perhaps the answer lies in quantum effects within the brain itself. Theories like Penrose and Hameroff’s orchestrated objective reduction propose that consciousness emerges from quantum processes in neural microtubules, where wavefunction collapse creates discrete moments of awareness.However, the leap from quantum mechanics to consciousness remains deeply controversial. Critics argue that the warm, noisy environment of the brain would destroy quantum coherence in nanoseconds, making any quantum theory of mind physically implausible. Others question whether exotic physics can resolve the hard problem of consciousness at all, or whether invoking quantum mechanics merely substitutes one mystery for another. As quantum computers begin to harness superposition and entanglement for computation, we face a provocative question: if consciousness truly requires quantum processes, might artificial minds ultimately depend not on better algorithms, but on entirely different physics? (shrink)

Causal–Continuity Stabilization Theory (CCST) characterizes macroscopic causal persistence as a physical stability property of finite substrates rather than as an ontological feature of the universal wavefunction. In its original formulation, CCST formalized descriptive admissibility: a coarse–grained macroscopic causal history remains well–posed only when thermodynamic dissipation stays below a substrate–dependent bound and when coarse–grained dynamical sensitivity preserves closure. This work develops an extension of CCST that targets a logically distinct stability question in Everettian dynamics: not only whether a macroscopic description (...) remains admissible within a branch, but whether a branch structure itself can remain dynamically coherent as an organized physical entity under sustained environmental coupling. Although unitary quantum mechanics preserves all components of the global quantum state [1, 2], organized branch structure may dynamically disperse into microscopic degrees of freedom under open–system dynamics, thereby losing the correlation patterns required for macroscopic organization [3, 4]. We distinguish structural dispersion (loss of branch–level organizational coherence) from Causal Exit (loss of description–level definability on a finite physical substrate), emphasizing that these correspond to stability failures at distinct physical layers and should not be conflated. We derive a dynamical weighting over coarse–grained path ensembles from open–system effective action and influence functional formalisms [5–7], showing how microscopic dynamics inducesanon–uniformstabilitygeometryinpathspacethroughirreversibledynamicalsuppression rather than probabilistic selection, without introducing collapse, selection rules, or inter–branch transport. Finally, a minimal toy model is introduced to visualize the qualitative sensitivity of branch structural persistence under controlled stability thresholds. The model is strictly illustrative and is accompanied by transparent parameter definitions and a reproducible numerical implementation in the appendix. (shrink)

The philosophy of superdeterminism is based on a single scientific fact about the universe, namely that cause and effect in physics are not real. The Many Worlds Interpretation (MWI) of quantum mechanics says that the universal wavefunction, which mathematically describes the state of all particles and forces in the universe, is objectively real and never collapses. Instead of a single outcome manifesting from a quantum measurement, all possible outcomes are realized, each in its own distinct, non-interacting “world.” However, the (...) proof of superdeterminism demonstrates a violation of Special Relativity under the Many Worlds interpretation. If MWI's branching is understood as the emergence of distinct, non-interfering histories within this static block multiverse, a problem arises concerning how these branches objectively delineate themselves when their defining events—the measurements—possess a relative temporal order. This scenario implies that the fundamental geometry or topology of the multiverse's branching is not an objective, frame-independent feature. Such a frame-dependent definition of branching effectively establishes a preferential frame of reference for determining the universe's fundamental structure. This directly violates Special Relativity's core tenet that the laws of physics are identical in all inertial frames and that no single frame is privileged. Moreover, there is no good reason to posit the MWI as an explanation for other possible random quantum events that could not have existed through any natural mechanism disproven by superdeterminism. Furthermore, Dr. Hansson’s proof that physical reality is timeless disproves the deterministic universal wave function under the MWI. Consequently, the philosophy of superdeterminism dismisses the Many Worlds interpretation of quantum mechanics under Dr. Hansson’s proof of superdeterminism. (shrink)