Multi-time wave functions are wave functions for multi-particle quantum systems that involve several time variables. In this paper we contrast them with solutions of wave equations on a space–time with multiple timelike dimensions, i.e., on a pseudo-Riemannian manifold whose metric has signature such as \ or \, instead of \. Despite the superficial similarity, the two behave very differently: whereas wave equations in multiple timelike dimensions are typically mathematically ill-posed and presumably unphysical, relevant Schrödinger equations for multi- (...) class='Hi'>time wave functions possess for every initial datum a unique solution on the spacelike configurations and form a natural covariant representation of quantum states. (shrink)

This paper introduces a new theory in temporal ontology, ‘wave theory’, and argues for its attractions over and above existing tensed theories of time.

A one-dimensional scattering problem off a δ-shaped potential is solved analytically and the time development of a wave packet is derived from the time-dependent Schrödinger equation. The exact and explicit expression of the scattered wave packet supplies us with interesting information about the “time delay” by potential scattering in the asymptotic region. It is demonstrated that a wave packet scattered by a spin-flipping potential can give us quite a different value for the delay times from that obtained (...) without spin-degrees of freedom. (shrink)

A nonlinear partial differential equation is derived which admits plane solitary waves on a conformally flat Riemannian space-time. The metric is determined by the amplitude of these waves. By interpreting these solitary waves as particles we arrive at the following picture: these particles are confined to regions exhibiting singular (very large) amplitudes in an otherwise continuous wavetrain. There is, thus, no distinction between the notion of a particle and that of a wave.

Misinformation perceptions related to global crises such as COVID-19 can have negative ramifications for democracy. Beliefs related to the prevalence of falsehoods may increase news avoidance or even vaccine hesitancy – a problematic context for successful interventions and policymaking. To explore how misinformation beliefs developed over a six-month pandemic period and how they corresponded to (digital) media preferences and selective exposure to the news, we rely on a five-wave panel survey conducted in the Netherlands (N =1,742). Our main findings show (...) that misinformation perceptions got more pronounced as the pandemic evolved. Social media use related to more pronounced misinformation beliefs within waves, whereas mainstream news use corresponded to less pronounced misinformation beliefs. An important implication for journalists and policymakers is to lower the over-time accumulation of misinformation perceptions, for example, by increasing transparency and acknowledging “honest mistakes.”. (shrink)

This study presents a modified simplest equation method to investigate some real and exact solutions of conformable time fractional Benjamin-Bona-Mahony equation and Chan-Hilliard equation. We use traveling wave transformation to obtain the results in the form of series solution. Some calculations are performed through Mathematica software to analyze the accuracy of this approach. Graphical representations are reported for more significant results at different fractional-order which demonstrates that this approach is very simple, adequate, and legitimate.

The idea of obtaining a pilot-wave quantum theory on a lattice with discrete time is presented. The motion of quantum particles is described by a \-distributed Markov chain. Stochastic matrices of the process are found by the discrete version of the least-action principle. Probability currents are the consequence of Hamilton’s principle and the stochasticity of the Markov process is minimized. As an example, stochastic motion of single particles in a double-slit experiment is examined.

This book offers the first comprehensive introduction to wave scattering in nonstationary materials. G. F. Roach's aim is to provide an accessible, self-contained resource for newcomers to this important field of research that has applications across a broad range of areas, including radar, sonar, diagnostics in engineering and manufacturing, geophysical prospecting, and ultrasonic medicine such as sonograms. New methods in recent years have been developed to assess the structure and properties of materials and surfaces. When light, sound, or some other (...) wave energy is directed at the material in question, "imperfections" in the resulting echo can reveal a tremendous amount of valuable diagnostic information. The mathematics behind such analysis is sophisticated and complex. However, while problems involving stationary materials are quite well understood, there is still much to learn about those in which the material is moving or changes over time. These so-called non-autonomous problems are the subject of this fascinating book. Roach develops practical strategies, techniques, and solutions for mathematicians and applied scientists working in or seeking entry into the field of modern scattering theory and its applications. Wave Scattering by Time-Dependent Perturbations is destined to become a classic in this rapidly evolving area of inquiry. (shrink)

There have been times in the history of ethical theory, especially in this century, when moral realism was down, but it was never out. The appeal of this doctrine for many moral philosophers is apparently so strong that there are always supporters in its corner who seek to resuscitate the view. The attraction is obvious: moral realism purports to provide a precious philosophical good, viz., objectivity and all that this involves, including right answers to (most) moral questions, and the possibility (...) of knowing those answers. In the last decade, moral realism has re-entered the philosophical ring in powerful-looking naturalistic form. ln this paper we provide a dialectical overview: we situate the new wave position itself, and also our objections to it, in the context of the evolving program of philosophical naturalism in 20th century analytic philosophy. We seek to show that although this new contender might initially look like championship material, it succumbs to punches surprisingly similar to those that knocked out the old-fashioned versions of naturalist moral realism. (shrink)

What is the quantum state of the universe? Although there have been several interesting suggestions, the question remains open. In this paper, I consider a natural choice for the universal quantum state arising from the Past Hypothesis, a boundary condition that accounts for the time-asymmetry of the universe. The natural choice is given not by a wave function but by a density matrix. I begin by classifying quantum theories into two types: theories with a fundamental wave function and theories (...) with a fundamental density matrix. The Past Hypothesis is compatible with infinitely many initial wave functions, none of which seems to be particularly natural. However, once we turn to density matrices, the Past Hypothesis provides a natural choice---the normalized projection onto the Past Hypothesis subspace in the Hilbert space. Nevertheless, the two types of theories can be empirically equivalent. To provide a concrete understanding of the empirical equivalence, I provide a novel subsystem analysis in the context of Bohmian theories. Given the empirical equivalence, it seems empirically underdetermined whether the universe is in a pure state or a mixed state. Finally, I discuss some theoretical payoffs of the density-matrix theories and present some open problems for future research. (Bibliographic note: the thesis was submitted for the Master of Science in mathematics at Rutgers University.). (shrink)

Traveling-wave solutions of the standard and compound form of Korteweg–de Vries–Burgers equations are found using factorizations of the corresponding reduced ordinary differential equations. The procedure leads to solutions of Bernoulli equations of non-linearity 3/2 and 2 (Riccati), respectively. Introducing the initial conditions through an imaginary phase in the traveling coordinate, we obtain all the solutions previously reported, some of them being corrected here, and showing, at the same time, the presence of interesting details of these solitary waves that (...) have been overlooked before this investigation. (shrink)

There have been times in the history of ethical theory, especially in this century, when moral realism was down, but it was never out. The appeal of this doctrine for many moral philosophers is apparently so strong that there are always supporters in its corner who seek to resuscitate the view. The attraction is obvious: moral realism purports to provide a precious philosophical good, viz., objectivity and all that this involves, including right answers to (most) moral questions, and the possibility (...) of knowing those answers. In the last decade, moral realism has re-entered the philosophical ring in powerful-looking naturalistic form. ln this paper we provide a dialectical overview: we situate the new wave position itself, and also our objections to it, in the context of the evolving program of philosophical naturalism in 20th century analytic philosophy. We seek to show that although this new contender might initially look like championship material, it succumbs to punches surprisingly similar to those that knocked out the old-fashioned versions of naturalist moral realism. (shrink)

If the energy-absorbing radio-frequency spin-flipping device used in perfect crystal neutron interferometry is an intermediate measuring device, then the experimental results contradict the associated wave packet collapse and support the real existence of the de Broglie pilot waves in both arms while the neutron travels in only one.

The purpose of the present chapter is to respond to a thread of recent criticism against one candidate framework for interpreting quantum theories, a framework introduced and defended by David Albert and Barry Loewer: wave function realism, a framework for interpreting the ontology of quantum theories according to which what appears to be a nonseparable metaphysics ofentangled objects acting instantaneously across spatial distances is a manifestation of a more fundamental separable and local metaphysics in higher dimensions. Thechapterconsiders strategies for extending (...) the wave function realist interpretation of quantum mechanics to the case of relativistic quantum theories, responding to arguments that this cannot be done. (shrink)

We illustrate, using a simple model, that in the usual formulation the time-component of the Klein–Gordon current is not generally positive definite even if one restricts allowed solutions to those with positive frequencies. Since in de Broglie's theory of particle trajectories the particle follows the current this leads to difficulties of interpretation, with the appearance of trajectories which are closed loops in space-time and velocities not limited from above. We show that at least this pathology can be avoided (...) if one adapts in a covariant form the formulation of relativistic point particle dynamics proposed by Gitman and Tyutin. (shrink)

In this paper, we investigate non-homogeneous wave equations in fractional space-time domains of space dimension _D_, \(0 and time dimension \(\beta\), \(0. We write the wave equations in terms of potential functions and non-zero source terms. For scalar source terms, the potential functions are also scalar functions, and for vector source terms, the potential functions are vector functions. We derived an expression for the wave to propagate from the source point to the observation point. The study shows that (...) the time for a wave to propagate from the source point to the observation point in a fractional space-time domain could be different from that in an integer order space-time domain. (shrink)

The strength and defects of wave mechanics as a theory of chemistry are critically examined. Without the secondary assumption of wave–particle duality, the seminal equation describes matter waves and leaves the concept of point particles undefined. To bring the formalism into line with the theory of special relativity, it is shown to require reformulation in hypercomplex algebra that imparts a new meaning to electron spin as a holistic spinor, eliminating serious current misconceptions in the process. Reformulation in the curved (...) space–time of general relativity requires the recognition of nonlinear effects that invalidate the practice of linear combination of atomic orbitals, ubiquitous in quantum chemistry, and redefines the electron as a nondispersive wave packet, or soliton. (shrink)

This book draws out Woolf’s insights into the fundamental structures of existence and experience by showing how the empirical and contingent elements of her dramaturgy are actually in the service of a metaphysical understanding of the human condition.

The origin of the wave properties of matter is discussed from the point of view of stochastic electrodynamics. A nonrelativistic model of a charged particle with an effective structure embedded in the random zeropoint radiation field reveals that the field induces a high-frequency vibration on the particle; internal consistency of the theory fixes the frequency of this jittering at mc2/ħ. The particle is therefore assumed to interact intensely with stationary zeropoint waves of this frequency as seen from its proper (...) frame of reference; such waves, identified here as de Broglie's phase waves, give rise to a modulated wave in the laboratory frame, with de Broglie's wavelength and phase velocity equal to the particle velocity. The time-independent equation that describes this modulated wave is shown to be the stationary Schrödinger equation (or the Klein-Gordon equation in the relativistic version). In a heuristic analysis appled to simple periodic cases, the quantization rules are recovered from the assumption that for a particle in a stationary state there must correspond a stationary modulation.Along an independent and complementary line of reasoning, an equation for the probability amplitude in configuration space for a particle under a general potential V(x) is constructed, and it is shown that under conditions derived from stochastic electrodynamics it reduces to Schrödinger's equation. This equation reflects therefore the dual nature of the quantum particles, by describing simultaneously the corresponding modulated waveand the ensemble of particles. (shrink)

The field of memory studies has traditionally been framed through a linear, wave-based model that assumes theoretical and methodological substitution over time. However, this essay challenges the limitations of this zero-sum logic, particularly regarding the third and fourth waves of contemporary memory studies. Using The Politics and Rhetoric of Collective Remembering (Milani, T., & Richardson, J. E. (Eds.). [2024]. The politics and rhetoric of collective remembering. Routledge) and Critical Memory Studies: New Approaches (Kaplan, B. A. [2023]. Critical memory (...) studies: New approaches. Bloomsbury) as focal points, this review highlights the complementary rather than substitutive nature of these approaches. The third wave, characterized by critical rhetorical analysis, interrogates the construction and function of collective memory within power structures, while the fourth wave foregrounds grassroots, activist, and bottom-up memory practices as tools of resistance. By juxtaposing these anthologies, this essay argues for an integrated, multidirectional conception of the field – one that acknowledges the coexistent fronts of memory studies and the crucial role of rhetorical analysis in advancing both waves. Rather than adhering to rigid paradigms of disciplinary progression, this essay advocates for a more expansive and interdisciplinary understanding of memory studies, emphasizing its evolving intersections with rhetoric and activism. (shrink)

Relative motion of particles is examined in the context of relational space-time. It is shown that de Broglie waves may be derived as a representation of the coordinate maps between the rest-frames of these particles. Energy and momentum are not absolute characteristics of these particles, they are understood as parameters of the coordinate maps between their rest-frames. It is also demonstrated the position of a particle is not an absolute, it is contingent on the frame of reference used (...) to observe the particle. (shrink)

In this unfolding digital genesis, time itself becomes a web—a network of connections and possibilities, each thread woven with intention and innovation. When we consider the beginning of time, we are drawn back to the story of Genesis—a narrative that speaks to the unfolding of existence from the void. Like light, which exhibits dual qualities as both particle and wave, time also embodies this duality. Imagine time as a vast ocean where each moment is a droplet, (...) a particle influencing and being influenced by countless others. At the same time, this ocean flows in waves, carrying the essence of past, present, and future in a seamless continuum. To grasp the concept of time in this way is to see it not as a straight line or a simple cycle, but as an intricate, multidimensional web where each node, each moment, is connected to all others. Just as a spider’s web vibrates with the slightest touch, so too does the time web respond to every action, decision, and thought. This idea transforms our understanding of time, suggesting that it is not merely a series of sequential events but a living, breathing network where the past, present, and future are in constant dialogue, reshaping each other. The Bible provides profound insights into the nature of time, portraying it as both linear and cyclical. The linear perspective is seen in the narrative arc from creation to eschatology, emphasizing a purposeful progression toward an ultimate goal. Meanwhile, the cyclical view is evident in the rhythms of festivals, seasons, and natural cycles, which emphasize the eternal return and renewal inherent in creation. These dual aspects reflect a divine balance, suggesting that time encompasses both the journey toward fulfillment and the repetition of sacred cycles. This duality mirrors the qualities of time as both web and wave—each thread and flow interconnected, each cycle and line carrying its own significance. (shrink)

Objective: To clarify whether long time constant is useful for detecting the after-slow activity of epileptiform discharges : sharp waves and spikes and for differentiating EDs from sharp transients.Methods: We employed 68 after-slow activities preceded by 32 EDs and 36 Sts from 52 patients with partial and generalized epilepsy defined by visual inspection. High-frequency activity associated with the apical component of EDs and Sts was also investigated to endorse two groups. After separating nine Sts that were labeled by (...) visual inspection but did not fulfill the amplitude criteria for after-slow of Sts, 59 activities were analyzed about the total area of after-slow under three TCs.Results: Compared to Sts, HFA was found significantly more with the apical component of EDs. The total area of after-slow in all 32 EDs under TC 2 s was significantly larger than those under TC 0.3 s and 0.1 s. Conversely, no significant differences were observed in the same parameter of 27 Sts among the three different TCs. Regarding separated nine Sts, the total area of after-slow showed a similar tendency to that of 27 Sts under three different TCs.Significance: These results suggest that long TC could be useful for selectively endorsing after-slow of EDs and differentiating EDs from Sts. These findings are concordant with the results of the HFA analysis. Visual inspection is also equally good as the total area of after-slow analysis. (shrink)

We investigate the meaning of the wave function by analyzing the mass and charge density distributions of a quantum system. According to protective measurement, a charged quantum system has effective mass and charge density distributing in space, proportional to the square of the absolute value of its wave function. In a realistic interpretation, the wave function of a quantum system can be taken as a description of either a physical field or the ergodic motion of a particle. The essential difference (...) between a field and the ergodic motion of a particle lies in the property of simultaneity; a field exists throughout space simultaneously, whereas the ergodic motion of a particle exists throughout space in a time-divided way. If the wave function is a physical field, then the mass and charge density will be distributed in space simultaneously for a charged quantum system, and thus there will exist gravitational and electrostatic self-interactions of its wave function. This not only violates the superposition principle of quantum mechanics but also contradicts experimental observations. Thus the wave function cannot be a description of a physical field but a description of the ergodic motion of a particle. For the later there is only a localized particle with mass and charge at every instant, and thus there will not exist any self-interaction for the wave function. Which kind of ergodic motion of particles then? It is argued that the classical ergodic models, which assume continuous motion of particles, cannot be consistent with quantum mechanics. Based on the negative result, we suggest that the wave function is a description of the quantum motion of particles, which is random and discontinuous in nature. On this interpretation, the square of the absolute value of the wave function not only gives the probability of the particle being found in certain locations, but also gives the probability of the particle being there. We show that this new interpretation of the wave function provides a natural realistic alternative to the orthodox interpretation, and its implications for other realistic interpretations of quantum mechanics are also briefly discussed. (shrink)

When Einstein formulated his special relativity, he developed his dynamics for point particles. Of course, many valiant efforts have been made to extend his relativity to rigid bodies, but this subject is forgotten in history. This is largely because of the emergence of quantum mechanics with wave-particle duality. Instead of Lorentz-boosting rigid bodies, we now boost waves and have to deal with Lorentz transformations of waves. We now have some nderstanding of plane waves or running waves (...) in the covariant picture, but we do not yet have a clear picture of standing waves. In this report, we show that there is one set of standing waves which can be Lorentz-transformed while being consistent with all physical principle of quantum mechanics and relativity. It is possible to construct a representation of the Poincaré group using harmonic oscillator wave functions satisfying space-time boundary conditions. This set of wave functions is capable of explaining the quantum bound state for both slow and fast hadrons. In particular it can explain the quark model for hadrons at rest, and Feynman’s parton model hadrons moving with a speed close to that of light. (shrink)

We apply a method analogous to the eikonal approximation to the Maxwell wave equations in an inhomogeneous anisotropic medium and geodesic motion in a three dimensional Riemannian manifold, using a method which identifies the symplectic structure of the corresponding mechanics, to the five dimensional generalization of Maxwell theory required by the gauge invariance of Stueckelberg's covariant classical and quantum dynamics. In this way, we demonstrate, in the eikonal approximation, the existence of geodesic motion for the flow of mass in a (...) four dimensional pseudo-Riemannian manifold. These results provide a foundation for the geometrical optics of the five dimensional radiation theory and establish a model in which there is mass flow along geodesics. We then discuss the interesting case of relativistic quantum theory in an anisotropic medium as well. In this case the eikonal approximation to the relativistic quantum mechanical current coincides with the geodesic flow governed by the pseudo-Riemannian metric obtained from the eikonal approximation to solutions of the Stueckelberg–Schrödinger equation. The locally symplectic structure which emerges is that of a generally covariant form of Stueckelberg's mechanics on this manifold. (shrink)

The single-particle wave function ψ=ReiS/h has been interpreted classically: At a given point the particle momentum is ▽S, and the relative particle density in an ensemble is R 2 . It is first proposed to modify this interpretation by assuming that physical variables undergo rapid fluctuations, so that ▽S is the average of the momentum over a short time interval. However, it appears that this is not enough. It seems necessary to assume that the density also fluctuates. The fluctuations (...) are taken to be random and to satisfy conditions required for agreement with quantum mechanics. In some cases the fluctuating density may take on instantaneous negative values. One gets agreement with quantum mechanics for the spin correlations of two particles in a singlet state. This comes about because of the correlations between the fluctuations of the variables of the two particles, the effect of which is equivalent to an action at a distance. The relation to Bell's inequality is discussed. (shrink)

Scientific endeavour has often tried to localize superior cerebral functions either in areas like the ones described by Broca as being those connected with language in the left hemisphere, or in the huge array of the hundred billion of interconnected neurons. But in this last case the coined description of the grandmother neuron, tends to show humorously that hopes have fallen short of their target.Along the same lines, the specific timing of electric neural activity is known to take place around (...) a few milliseconds, which seems to be insufficient to account for the high potential speed necessary to sustain the very massive and complex process which is involved in mental activity. (shrink)

One argument for the moving spotlight theory is that it better explains certain aspects of our temporal phenomenology than does any static theory of time. Call this the argument from passage phenomenology. In this paper it is argued that insofar as moving spotlight theorists take this to be a sound argument they ought embrace a new version of the moving spotlight theory according to which the moving spotlight is a cresting wave of causal efficacy. On this view it is (...) more than just presentness that is temporary: a range of other fundamental properties are also temporary because presentness synchronically changes the fundamental properties that are instantiated in the present moment, from those instantiated when that moment is future, or past. On this view having experiences as of presentness co-varies with the presence of presentness, allowing the moving spotlight theorist to provide a compelling explanation for why we have the temporal phenomenology we do, and to explain how we can know that we are present by reflecting on the nature of said phenomenology. (shrink)

Scientific realism is the view that our best scientific theories can be regarded as (approximately) true. This is connected with the view that science, physics in particular, and metaphysics could (and should) inform one another: on the one hand, science tells us what the world is like, and on the other hand, metaphysical principles allow us to select between the various possible theories which are underdetermined by the data. Nonetheless, quantum mechanics has always been regarded as, at best, puzzling, if (...) not contradictory. As such, it has been considered for a long time at odds with scientific realism, and thus a naturalized quantum metaphysics was deemed impossible. Luckily, now we have many quantum theories compatible with a realist interpretation. However, scientific realists assumed that the wave-function, regarded as the principal ingredient of quantum theories, had to represent a physical entity, and because of this they struggled with quantum superpositions. In this paper I discuss a particular approach which makes quantum mechanics compatible with scientific realism without doing that. In this approach, the wave-function does not represent matter which is instead represented by some spatio-temporal entity dubbed the primitive ontology: point-particles, continuous matter fields, space-time events. I argue how within this framework one develops a distinctive theory-construction schema, which allows to perform a more informed theory evaluation by analyzing the various ingredients of the approach and their inter-relations. (shrink)

This volume collects many of the major essays of feminist theory of the past forty years. The essays included here are those which have made key contributions to feminist theory during this period and which have generated extensive discussion. The volume organizes these essays historically, so as to provide a sense of the major turning points in feminist theory. Beginning with those essays which have provoked widespread discussion in the early days of the second wave, the volume then presents essays (...) which have been central to major discussions since that time. The essays present the complex relationship between feminism and Marxism, the second wave's "gynocentric turn," the theoretical elaboration of differences among women, and the essentialist debate, as these have occupied the attention of feminist theorists. Through this collection, the reader is able to gain a sense of the diverse directions feminist theory has taken over the past forty years, where feminist theory stands at the moment, and the questions which are just now beginning to emerge. (shrink)

This selection of new approaches to the comparative study of religious ethics provides an accessible introduction to the most current research in the field. The essays in this book show that a variety of approaches to religious ethics are worth pursuing in our contemporary, profusely interconnected world. They also demonstrate that many sorts of analysis are shaped by comparison and comparative interests, even when they focus on a single topic or question, as long as they are informed by analogous studies (...) of other traditions, cultures, or religions. The volume exemplifies a thought-provoking, multidisciplinary engagement with global ethics today. (shrink)

This paper defends wave function realism against the charge that the view is empirically incoherent because our evidence for quantum theory involves facts about objects in three-dimensional space or space-time . It also criticizes previous attempts to defend wave function realism against this charge by claiming that the wave function is capable of grounding local beables as elements of a derivative ontology.

It is hypothesized that de Broglie’s ‘matter waves’ provide a dynamical basis for Minkowski spacetime in an antisubstantivalist or relational account. The relativity of simultaneity is seen as an effect of the de Broglie oscillation together with a basic relativity postulate, while the dispersion relation from finite rest mass gives rise to the differentiation of spatial and temporal axes. Thus spacetime is seen as not fundamental, but rather as emergent from the quantum level. A result by Solov’ev which demonstrates (...) that time is not an applicable concept at the quantum level is adduced in support of this claim. Finally, it is noted that de Broglie waves can be seen as the “bridge of becoming” discussed by ( 2005 ). (shrink)

The Hoffmann reflex (H-wave) is produced by alpha-motoneuron activation in the spinal cord. A feature of this electromyography response is that it exhibits fluctuations in amplitude even during repetitive stimulation with the same intensity of current. We herein explore the hypothesis that physical training induces plastic changes in the motor system. Such changes are evaluated with the fractal dimension (FD) analysis of the H-wave amplitude-fluctuations (H-wave FD) and the cross-covariance (CCV) between the bilateral H-wave amplitudes. The aim of this study (...) was to compare the H-wave FD as well as the CCV before and after track training in sedentary individuals and athletes. The training modality in all subjects consisted of running three times per week (for 13 weeks) in a concrete road of 5 km. Given the different physical condition of sedentary vs. athletes, the running time between sedentary and athletes was different. After training, the FD was significantly increased in sedentary individuals but significantly reduced in athletes, although there were no changes in spinal excitability in either group of subjects. Moreover, the CCV between bilateral H-waves exhibited a significant increase in athletes but not in sedentary individuals. These differential changes in the FD and CCV indicate that the plastic changes in the complexity of the H-wave amplitude fluctuations as well as the synaptic inputs to the Ia-motoneuron systems of both legs were correlated to the previous fitness history of the subjects. Furthermore, these findings demonstrate that the FD and CCV can be employed as indexes to study plastic changes in the human motor system. (shrink)

During the communist era, Radio Free Europe (RFE) was Romania's favorite radio station. This paper analyzes the role of RFE in everyday life in the strictly controlled Romanian communist state by looking at the broadcasts of RFE's Romanian Department, their audience, and their impact. Drawing largely on the RFE archives at the Vera and Donald Blinken Open Society Archives (OSA) and the former secret police files at the National Council for the Study of the Securitate Archives (CNSAS), it investigates how (...) radio waves mediated and channeled information while preparing people to embrace political and cultural change. The paper focuses on the circulation of knowledge, media confluences, and human agency. The rituals that developed around the secrecy which governed the listening process, the personal requests, attitudes, and opinions expressed in letters to RFE, and oral and written testimonies, coupled with the disproportionate and, at times, extreme reactions of the communist state, together reveal the carving out of individual spaces that allowed for the preservation of the “self” during Nicolae Ceausescu's dictatorship. At such critical historical moments, the connection became visible. Through an analysis of recent media representations in which RFE figures, such as Cold Waves, this study also looks at how RFE shaped personal memories of communist times. (shrink)

The article explores the rich and varied experiences of a collective writing project, unfolding through an anecdote involving Charlie, a young boy who creatively disrupted conventional photography methods. This incident, during an evening promenade by the sea in Ericeira (Portugal), epitomizes the project's embrace of playfulness and exploration of diverse perspectives–materialized through Charlie's playful insistence on experimenting with different angles. The event embodied the group’s approach to writing, leading to a collective inquiry into the interplay of ages, angles, and other (...) themes like waves, threads, shadows, and liminal spaces. The project, driven by the Between Ages Collective, began with informal gatherings in Plymouth, UK, and expanded into a year-long online reading group. Participants, spanning different generations and academic stages, shared various materials, including films, picture books, and scholarly texts, which inspired individual contributions. Influenced by the Collective's collaborative spirit, these contributions explore the concept of 'between ages' – a metaphorical and literal space of transition and fluidity. Contributors were invited to craft pieces that delve into the 'between ages' theme, often exploring serendipitous moments that transform interactions and experiences. The writing tries to capture a sense of openness and curiosity, embracing the uncertainties and ambiguities inherent in the process. The works do not strictly adhere to conventional academic or narrative forms but rather emerge from the collective's shared experiences, including cooking, eating, swimming and walking together. The article suggests that these writings are not meant to be definitive or conclusive but are explorations that invite readers to engage with the mundane and profound textures of everyday life. The stories and themes explored are marked by their diversity in style, rhythm, and imagery, ranging from reflections on the philosophy of shadows to the profound implications of intergenerational and interspecies relationships. The Collective’s work is presented as an ongoing experiment in thinking and writing together, with each piece offering unique insights into the fluid and often blurred boundaries between different states of being. This openness to the in-between spaces brings into question the notion of fixed identities and experiences, inviting a more nuanced understanding of the relational dynamics that shape existence. The article allows the readers to delve into these narratives and engage with the myriad ways they resonate with broader themes of being, storying, and connecting. (shrink)

The representation of a quantum system as the spatial configuration of its constituents evolving in time as a trajectory under the action of the wave-function, is the main objective of the de Broglie–Bohm theory. However, its standard formulation is referred to the statistical ensemble of its possible trajectories. The statistical ensemble is introduced in order to establish the exact correspondence between the probability density on the spatial configurations and the quantum distribution, that is the squared modulus of the wave-function. (...) In this work we explore the possibility of using the pilot wave theory at the level of a single Bohm’s trajectory, that is a single realization of the time dependent configuration which should be representative of a single realization of the quantum system. The pilot wave theory allows a formally self-consistent representation of quantum systems as a single Bohm’s trajectory, but in this case there is no room for the Born’s rule at least in its standard form. We will show that a correspondence exists between the statistical distribution of configurations along the single Bohm’s trajectory and the quantum distribution for a subsystem interacting with the environment in a multicomponent system. To this aim, we present the numerical results of the single Bohm’s trajectory description of the model system of six confined planar rotors with random interactions. We find a rather close correspondence between the coordinate distribution of one rotor, the others representing the environment, along its trajectory and the time averaged marginal quantum distribution for the same rotor. This might be considered as the counterpart of the standard Born’s rule when the pilot wave theory is applied at the level of single Bohm’s trajectory. Furthermore a strongly fluctuating behavior with a fast loss of correlation is found for the evolution of each rotor coordinate. This suggests that a Markov process might well approximate the evolution of the Bohm’s coordinate of a single rotor and, under this condition, it is shown that the correspondence between coordinate distribution and quantum distribution of the rotor is exactly verified. (shrink)

This textbook offers the first unified treatment of wave propagation in electronic and electromagnetic systems and introduces readers to the essentials of the transfer matrix method, a powerful analytical tool that can be used to model and study an array of problems pertaining to wave propagation in electrons and photons. It is aimed at graduate and advanced undergraduate students in physics, materials science, electrical and computer engineering, and mathematics, and is ideal for researchers in photonic crystals, negative index materials, left-handed (...) materials, plasmonics, nonlinear effects, and optics. Peter Markos and Costas Soukoulis begin by establishing the analogy between wave propagation in electronic systems and electromagnetic media and then show how the transfer matrix can be easily applied to any type of wave propagation, such as electromagnetic, acoustic, and elastic waves. The transfer matrix approach of the tight-binding model allows readers to understand its implementation quickly and all the concepts of solid-state physics are clearly introduced. Markos and Soukoulis then build the discussion of such topics as random systems and localized and delocalized modes around the transfer matrix, bringing remarkable clarity to the subject. Total internal reflection, Brewster angles, evanescent waves, surface waves, and resonant tunneling in left-handed materials are introduced and treated in detail, as are important new developments like photonic crystals, negative index materials, and surface plasmons. Problem sets aid students working through the subject for the first time. (shrink)

In the approximation that every inertial observer experiences a homogeneous, uniform flow of time and sees a space that is Euclidean, the arena of physics is Minkowskian and one speed is the same in all intertial frames. If a given intertial observer finds an infinitesimal source or particle traveling faster than this fundamental speed near a given event, the source must appear in some inertial frame spread over neighboring positions at a given time as a spacelike structure. If (...) this structure persists over a period of proper time, it can be interpreted as a wave group. If it is conserved, it can be interpreted as a line or tube of force. (shrink)

It is assumed that the motion of a particle in spacetime does not depend on the motion relative to it of any observer or of any frame of reference. Thus if the particle has an internal vibration of the type hypothesized by de Broglie, the phase of that vibration at any point in spacetime must appear to be the same to all observers, i.e., the same in all frames of reference. Each observer or reference frame will have its own de (...) Broglie wave for the particle. The phase of the particle's vibration must, by definition, be the same as that of all possible de Broglie waves at the point where the particle is. By superimposing all these possible de Broglie waves, a wave packet is formed centered in space on the particle. The formation of such a packet is discussed with the help of spacetime diagrams; the packet does not spread with time. The relevance of this packet to the wave mechanics of Schrödinger is discussed; it is also pointed out that any vibration can lead to such a packet. (shrink)

This paper reviews recent applications of the Einstein- Rosen type space-times to some problems of modern cosmology. An extensive overview of inhomogeneous universes filled with gravitational waves, classical fields, and relativistic fluids is given. The dynamics of primordial inhomogeneities, such as gravitational and matter waves and shocks, their interactions, and the global evolution of the models considered, is presented in detail.

A Schrödinger-like relativistic wave equation of motion for the Lorentz-scalar potential is formulated based on a Lagrangian formalism of relativistic mechanics with a scaled time as the evolution parameter. Applications of this Schrödinger-like formalism for the Lorentz-scalar potential are given: For the square-step potential, the predictions of this formalism are free from the Klein paradox, and for the Coulomb potential, this formalism yields the exact bound-state eigenenergies and eigenfunctions.

We investigate and develop further two models, the GRW model and the K model, in which the Schrödinger evolution of the wave function is spontaneously and repeatedly interrupted by random, approximate localizations, also called “self-reductions” below. In these models the center of mass of a macroscopic solid body is well localized even if one disregards the interactions with the environment. The motion of the body shows a small departure from the classical motion. We discuss the prospects and the difficulties of (...) observing this anomaly. As far a the influence of the surroundings on submacroscopic objects (like dust particles) is concerned, we show that the estimates obtained recently in the theory of continuous measurements and in the K model are compatible. Also, we elaborate upon the relationship between the models. Firstly, borrowing a line of thought from the K model, we find the transition region between macroscopic and microscopic behaviors in the GRW model. Secondly, we refine the propagation rule of the wave function in the K model with the help of the time-evolution equation proposed in the GRW model. (shrink)

Isolated neutron stars undergoing non-radial oscillations are expected to emit gravitational waves in the kilohertz frequency range. To date, radio astronomers have located about 1,300 pulsars, and can estimate that there are about 2×108 neutron stars in the galaxy. Many of these are surely old and cold enough that their interiors will contain matter in the superfluid or superconducting state. In fact, the so-called glitch phenomenon in pulsars (a sudden spin-up of the pulsar's crust) is best described by assuming (...) the presence of superfluid neutrons and superconducting protons in the inner crusts and cores of the pulsars. Recently there has been much progress on modelling the dynamics of superfluid neutron stars in both the Newtonian and general relativistic regimes. We will discuss some of the main results of this recent work, perhaps the most important being that superfluidity should affect the gravitational waves from neutron stars (emitted, for instance, during a glitch) by modifying both the rotational properties of the background star and the modes of oscillation of the perturbed configuration. Finally, we present an analysis of the so-called zero-frequency subspace (i.e., the space of time-independent perturbations) and determine that it is spanned by two sets of polar (or spheroidal) and two sets of axial (or toroidal) degenerate perturbations for the general relativistic system. As in the Newtonian case, the polar perturbations are the g-modes which are missing from the pulsation spectrum of a non-rotating configuration, and the axial perturbations should lead to two sets of r-modes when the degeneracy of the frequencies is broken by having the background rotate. (shrink)

A practical experiment using coincidence techniques is suggested to test the validity of the following concepts:(1) wave packet reduction and(2) the measurement-uncertainty principle for position and momentum. The suggested experiment uses the time-of-flight method to determine an electron's momentum and a coincident photon, emitted from a system excited by the electron, to determine its initial position. It is shown that this method does constitute a simultaneous measurement of position and momentum for a single system. Also, it is pointed out (...) that the traditional statement of the measurementuncertainty principle must be slightly modified even within the Copenhagen interpretation of quantum mechanics. (shrink)