Relativistic Spacetime Research Articles

Relationship Between Conical Perspective, Hyperbolic Curves, and Hyperbolic Medicine

Perspective” is the art of representing objects in such a way that they are visualized from the observer’s point of view. Using this technique, a three-dimensional (3D) world is projected onto a two-dimensional (2D) Surface. “Conical perspective” is the one that interests us in hyperbolic medicine since it is the one that most closely approximates the reality we see. We call “hyperbolic medicine” (abbreviated “Medipérbola”) to the study of hyperbolic curves that occur in the physiology of a living being, especially in humans, about other hyperbolic curves that may be in nature, such as electromagnetic fields, expansion-contraction systems in motion, circadian rhythms, and space-time relativity. We think that when we observe an object, the conical perspective of that image is not parallel lines that converge at a point, but hyperbolic curves of space-time, and the hyperbolic curves that occur in human physiology would be related to them. The relationships between conic perspective, hyperbolic curves of space-time, and hyperbolic curves of human physiology have been studied. Conclusions: 1. Conic perspective represents images that travel at the speed of light to the eye of the observer, following hyperbolic curves of space-time. 2. Human vision is hyperbolic because the space in which we live is deformed by “hyperbolic curves”, which exist in any longitude and latitude of the earth’s geography. 3. Human physiology can be conditioned by these hyperbolic curves, to adapt to this hyperbolic deformation of the space in which we live.

Оркестрове письмо в опері «Соловей» І. Стравінського як засіб об’єктивації просторово-часових відносин

The aim of the article is to study principles of orchestral writing (that is individual system of technological devices and principles, aimed at objectivation of certain spacetime relations in timbral and textural structure of the work) in the opera “The Nightingale” by I. Stravinsky. In this research the author uses such methods as functional, comparative, stylistic. Scientific novelty of the article lies in the following: 1) in examination of orchestral writing in opera “The Nightingale” from the standpoint of stylistic turning point; 2) in comparative analysis of principles of orchestral writing in C. Debussy’s “Nuages” (“Clouds")” and I act of “The Nightingale”; 3) in revealing of specifics of orchestral writing in the II and III acts of beforementioned opera as a tool to objectify spacetime relations. Conclusions. In the I act the orchestral writing inclines to follow impressionistic writing (C. Debussy’s “Nuages”), which can be seen in creation of the spatial characteristic of the sound matter, obscuring the distinction between the relief and background, simultaneous usage of several elements bearing different functions, constructing of continuity through variant transfiguration of the motive invariants as well as by sustaining texture and timbres. It is stressed, that multi-figure principle functions from the I act. In the orchestral texture of II and III acts (written after acquiring experience of ballet composing) multi-elemental structure is applied, due to usage of timbre mixtures (often presented as rhythmical or intonational variants), splitting of orchestral functions, principle of multifigure composition and complementarity, thematization of the background, causing complex organisation of space and “dense” time, rich with events. Some principles of impressionistic writing are developed by I. Stravinsky in accordance with his individual stylistic beliefs. His orchestration shows further development of such principles, as: 1) modelling of heterogeneous sonic space; 2) obscuring of the border between the relief and background due to thematization of the musical texture.

Relativity Isoframes—A Useful and Potentially Unifying Conceptual Framework

This brief note introduces the conceptual framework of special and general relativity isoclocks and isoframes. Isoclocks and isoframes, as defined herein, can be used to create geometrical maps of space and time (“space-time”) with and without matter embedded. They are useful for having a mental picture of space-time relationships without having to picture 4-dimensional manifolds, which very few students and scientists are able to do. With the aid of the optical lensing definition of curvature as inverse radius, a new gravitational force equation is derived, which also incorporates Einstein’s mass/energy relation in the mx term. Thus, one may see how it is that gravitational force correlates with its time-embedded curvature-squared (Cx2) space in a more accurate formulation than could be envisioned by Newton. This becomes more apparent in high gamma fields, such as found near a black hole horizon. It is hoped that probability theories, such as quantum field theories in curved space-time, might be adaptable to the general relativity isoframe concept introduced herein.

HISTORICAL AND CULTURAL LANDSCAPE OF A SMALL URAL TOWN: IMAGES OF THE IRBIT FAIR IN THE ESSAY ON THE 19TH CENTURY

The article is devoted to the key image of the historical and cultural landscape of Irbit — the Irbit fair. Based on the essays of the 19th century, three main trends in the depiction of the fair seasons of Irbit, which are dominant in different decades, are considered. In the economic essays by E. A. Verderevsky and A. G. Khitrov, the distinctive features of the Irbit Fair were first identified, and the topics of “trust” and “riddles” of the fair that were important for the trading community were declared. The second tendency of description, developing in the letters of E. A. Verderevsky and travel sketches of N. D. Teleshov developed the image of the fair season as a carnival, providing rich material for understanding the fair as a dystopia (M. Foucault), with special space-time relations, interconnection isolation and permeability. The third tendency of the image is found in the sketches of the Uralites D. N. Mamin-Sibiryak and K. D. Nosilov, aimed at improving public mores. In their texts, the fair becomes a kind of provocative landscape, both attracting and repulsive to the authors. Throughout its history, the Irbit Fair has retained its attractiveness for ethnographers, writers and folklorists as a representation of a wide range of social strata and ethnic groups. At the same time, there is no single narrative about the fair. By the end of the 19th century, the Ural literature focused on describing and exposing the spontaneous destructive forces that seize the community and the person during the days of the fair, while it was at this time that the local merchant class used the language of architecture to manifest their own collective identity. The growing gap reveals its adherence to principles during a radical rethinking of the historical and cultural heritage of Irbit in the 1920s-1930s. The article connects local “fair plots”, compares the views “from the outside” and “from the inside”, condenses the description of the regional literary context.

ЭВОЛЮЦИЯ ПРОСТРАНСТВЕННО-ВРЕМЕННЫХ ПАРАМЕТРОВ АУДИОВИЗУАЛЬНЫХ ОБРАЗОВ В ПРОЦЕССЕ СОЗДАНИЯ ЭКРАННЫХ ПРОИЗВЕДЕНИЙ (НА МАТЕРИАЛЕ ФОТОГРАФИИ, КИНО, ТЕЛЕВИДЕНИЯ, ВИДЕО

On-screen creativity is a single cultural-aesthetic system, operating with the language of visual and audiovisual images, the basic source of which is inseparably linked with such categories of reality as space and time. Their special position is determined by the fact that they are attributes of the existence of life forms and without their reflection any on-screen creativity becomes impossible. At certain stages of its historical evolution, screen creativity grew by new typical formations. The photography appeared first, then the cinema, and later on television, in the depths of which, after a while, the video was parted. Each new type at the level of space-time relations with the reality preceeding the camera formed its own special principles of screen narration. At the same time, they depended on the features of the new technological system, and on the dominant modes of visuality on an individual and collective levels. In this process, the cultural-aesthetic progress in on-screen creativity was reflected. The general logic of the relationship of the author of the screen work and the displayed reality in terms of its on-screen chronotope organization has evolved from a single, instantaneous discretization of it, to a total space-time continuity. From the author’s point of view, the more speculative picture of this process looked as follows: the photographic chronotope is characterized by a single spatial appearance of the displayed object and its temporary immobility (static); the cinematic chronotope is characterized by an editorial multiplicity of forms of the displayed object, which recreates conditional space and conditional time on the screen; the television chronotope is characterized by a simultaneous multiplicity of forms of the displayed object, which recreates the conditional space and real time on the screen; the video chronotype is characterized by a continual multiplicity of shapes of the displayed object, which recreates real space and real time on the screen. It is obvious that the evolution of screen creativity stimulated the development of new creative possibilities in terms of the spatial and temporal organization of audiovisual images, which in turn contributed to the establishment and enrichment of specific cultural aesthetic formations. Their common aspiration was focused on achieving natural integrity and authenticity in presenting life forms on the screen.

Weyl geometry, topology of space-time and reality of electromagnetic potentials, and new perspective on particle physics

Consistency of Weyl natural gauge, Lorentz gauge and nonlinear gauge is studied in Weyl geometry. Field equations in generalized Weyl-Dirac theory show that spinless electron and photon are topological defects. Statistical metric and fluctuating metric in 3D space with time as a measure of spatial relations are discussed to propose a statistical interpretation of Maxwell field equations. It is argued that physical geometry is an approximation to mathematical geometry, and 4D relativistic spacetime is essentially 3D space with changing spatial relations. The present work is suggested to have radical new outlook on elementary particle physics.

Combining 3-Momentum and Kinetic Energy on Galilei/Newton Spacetime

Without the mass-energy equivalence available on Minkowski spacetime M, it is not possible on 4-dimensional non-relativistic Galilei/Newton spacetime G to combine 3-momentum and total mass-energy in a single tensor object. However, given a fiducial frame, it is possible to combine 3-momentum and kinetic energy into a linear form (particle) or (1,1) tensor (continuum) in a manner that exhibits increased unity of classical mechanics on flat relativistic and non-relativistic spacetimes M and G. As on M, for a material continuum on G, the first law of thermodynamics can be considered a consequence of a unified dynamical law for energy-momentum rather than an independent postulate.

The Drift Chamber detector of the FOOT experiment: Performance analysis and external calibration

The study that we present is part of the preparation work for the setup of the FOOT (FragmentatiOn Of Target) experiment whose main goal is the measurement of the double differential cross sections of fragments produced in nuclear interactions of particles with energies relevant for particle therapy. The present work is focused on the characterization of the gas-filled drift chamber detector composed of 36 sensitive cells, distributed over two perpendicular views. Each view consists of six consecutive and staggered layers with three cells per layer. We investigated the detector efficiency and we performed an external calibration of the space–time relations at the level of single cells. This information was then used to evaluate the drift chamber resolution. An external tracking system realized with microstrip silicon detectors was adopted to have a track measurement independent on the drift chamber. The characterization was performed with a proton beam at the energies of 228 and 80 MeV. The overall hit detection efficiency of the drift chamber has been found to be 0.929±0.008, independent on the proton beam energy. The spatial resolution in the central part of the cell is about 150±10μ m and 300±10μ m and the corresponding detector angular resolution has been measured to be 1.62±0.16 mrad and 2.1±0.4 mrad for the higher and lower beam energies, respectively. In addition, the best value on the intrinsic drift chamber resolution has been evaluated to be in the range 60−100μ m. In the framework of the FOOT experiment, the drift chamber will be adopted in the pre-target region, and will be exploited to measure the projectile direction and position, as well as for the identification of pre-target fragmentation events.

Conformal Invariance of the Newtonian Weyl Tensor

It is well-known that the conformal structure of a relativistic spacetime is of profound physical and conceptual interest. In this note, we consider the analogous structure for Newtonian theories. We show that the Newtonian Weyl tensor is an invariant of this structure.

Мысль и ее «одеяния»

The article develops a methodological conception. It is based on the principles of the philosophy of complexity. The author believes that the discussion of the problems of rationality in the space of cultural diversity will be futile if we do not take into account the cognitive and socio-cultural aspects of meaning generation. The author draws attention to the communicative nature of meaning formation, which is increasing in the context of globalization. Such forms of organization of collective thinking as an interdisciplinary and transdiciplinary dialogue spread to the philosophical community. A distinctive feature of historical and philosophical research remains a special attention to textual artifacts, but modern methodologies must also contribute to the understanding of ancient knowledge and mentality. The author offers a methodological model of meaning generation. The coordinate grid of axes is its basis. As bearing axes, the author introduces: conscious-unconscious, explicit-implicit (hidden), external-internal, linear-nonlinear, order-chaos, simple-complex, reflexive-pre-reflexive, discrete-continuum. The Genesis of ethno-cultural mentalities took place in unique natural, cultural, historical and linguistic conditions. As a result, cultures can differ in the types of perception of space-time relations. This is reflected in the variety of space-time models. The problem of pairing the personal, environmental and social worlds of time by A.A. Krushinskiy. He presented the hexagram model of time as a game of player-personality and player-society. In the complex process of meaning formation, the author identifies the conscious layer of language and speech, the semi-conscious layer of images, the unconscious layer of states and pre-reflexive understanding. In the course of global cognitive evolution, there were revolutionary turns towards the development of conscious speech from the depths of the unconscious. At the same time, different cultures had their own trajectories of rationality development, developing specific languages and mental models. Ideographic language such as Chinese stimulated the development of spatial-imaginative thinking based on visual algorithms. In alphabetic languages of Indo-European type, the linearity of speech is only the external plan of expression, while the nonlinear spatiality (geometric style) of meaning formation works in internal dimensions. Discussing the noumenal sources of meaning formation, the author addresses the understanding of the nature of thought in spiritual philosophies and modern cognitive research. Scientific research of deep, pre-reflexive layers of understanding in the general structure and dynamics of meaning formation can bring a new dimension to the discussion on the «geography of rationality». In the global world, when unique cultures interact, new harmonics of the general planetary consciousness are formed.

Derivation of Lighthill’s Eighth Power Law of an Aeroacoustic Quadrupole in Acoustic Spacetime

Acoustic spacetime is a four-dimensional manifold analogue to the relativistic spacetime with the reference speed of light replaced by the speed of sound. It has been established primarily for the indirect studies of relativistic phenomena by means of their better understood acoustic analogues. More recently, it has also been used for the analytical treatment of sound propagation in various uniform and non-uniform flows of the background fluid. In this paper the analogy is extended and utilized to derive Lighthill’s eight power law for sound generation of an aeroacoustic quadrupole. Adding to the existing analogue theory, propagating sound waves are described in terms of a weak perturbation of the background acoustic spacetime metric. The obtained result proves that the acoustic analogy can be extended to cover both weak perturbation of the fluid due to the sound waves and certain sound generation mechanisms, at least in incompressible low Mach number flows.

Solving the curvature and Hubble parameter inconsistencies through structure formation-induced curvature

Recently it has been noted by Di Valentino, Melchiorri and Silk (2019) that the enhanced lensing signal relative to that expected in the spatially flat ΛCDM model poses a possible crisis for the Friedmann–Lemaître–Robertson–Walker (FLRW) class of models usually used to interpret cosmological data. The ‘crisis’ amounts to inconsistencies between cosmological datasets arising when the FLRW curvature parameter Ω k0 is determined from the data rather than constrained to be zero a priori. Moreover, the already substantial discrepancy between the Hubble parameter as determined by Planck and local observations increases to the level of 5σ. While such inconsistencies might arise from systematic effects of astrophysical origin affecting the Planck cosmic microwave background (CMB) power spectra at small angular scales, it is an option that the inconsistencies are due to the failure of the FLRW assumption. In this paper we recall how the FLRW curvature ansatz is expected to be violated for generic relativistic spacetimes. We explain how the FLRW conservation equation for volume-averaged spatial curvature is modified through structure formation, and we illustrate in a simple framework how the curvature tension in a FLRW spacetime can be resolved—and is even expected to occur—from the point of view of general relativity. Requiring early-time convergence towards a Friedmannian model with a spatial curvature parameter Ω k0 equal to that preferred from the Planck power spectra resolves the Hubble tension within our dark energy-free model.

The Panasqueira Rare Metal Granite Suites and Their Involvement in the Genesis of the World-Class Panasqueira W–Sn–Cu Vein Deposit: A Petrographic, Mineralogical, and Geochemical Study

Elucidation of time-space relationships between a given wolframite deposit and the associated granites, the nature of the latter, and their alterations, is a prerequisite to establishing a genetic model. In the case of the world-class Panasqueira deposit, the problem is complicated because the associated granites are concealed and until now poorly known. The study of samples from a recent drill hole and a new gallery allowed a new approach of the Panasqueira granite system. Detailed petrographic, mineralogical, and geochemical studies were conducted, involving bulk major and trace analyses, BSE and CL imaging, EPMA, and SEM-EDS analyses of minerals. The apical part of the Pansqueira pluton consisted of a layered sequence of separate granite pulses, strongly affected by polyphase alteration. The use of pertinent geochemical diagrams (major and trace elements) facilitated the discrimination of magmatic and alteration trends. The studied samples were representative of a magmatic suite of the high-phosphorus peraluminous rare-metal granite type. The less fractionated members were porphyritic protolithionite granites (G1), the more evolved member was an albite-Li-muscovite rare metal granite (G4). Granites showed three types of alteration processes. Early muscovitisation (Ms0) affected the protolithionite in G1. Intense silicification affected the upper G4 cupola. Late muscovitisation (Fe–Li–Ms1) was pervasive in all facies, more intense in the G4 cupola, where quartz replacement yielded quartz-muscovite (pseudo-greisen) and muscovite only (episyenite) rocks. These alterations were prone to yield rare metals to the coeval quartz-wolframite veins.

Advancing Computational Methods to Understand the Dynamics of Ejection, Accretion, Winds, and Jets in Binary Neutron Star Mergers

AbstractWe introduce the HandOff, a set of computational tools to transfer general relativistic magnetohydrodynamic and spacetime data from the numerical code IllinoisGRMHD to Harm3d. While the former simulates binary neutron star (BNS) mergers in full dynamical General Relativity, the latter specializes in modeling accretion disks around black holes (BH) over long timescales. The HandOff, then, enables us to transfer the outcome of BNS mergers after BH formation from IllinoisGRMHD to Harm3d and to evolve the post-merger system efficiently over long timescales. We show our latest results in this respect, for matter modeled as a magnetized ideal-fluid, and discuss our future plans which involve incorporating advanced equations of state and neutrino physics into BNS simulations using the HandOff approach.

QUANTUM FIELD THEORY FROM FIRST PRINCIPLES

The mathematical description of quantum systems univocally identies their nature. In other words we treat a system as quantum if we describe its behaviour adopting Hilbert spaces and structures thereof, as prescribed by the postulates of quantum theory. The choice of using quantum systems as the elementary systems of physics can be justied in terms of informational principles, thanks to results of the last decade. Such results come as the conclusion of a research program that lasted almost one century, with the aim of reformulating quantum theory in terms of operational principles. This achievement now poses a new challenge, that we face here. If the systems of quantum theory are thought of as elementary information carriers in the rst place, rather than elementary constituents of matter, and their connections are logical connections within a given algorithm, rather than space-time relations, then we need to nd the origin of mechanical concepts—that characterise quantum mechanics as a theory of physical systems. To this end,we will illustrate howphysical laws can be viewed as algorithms for the update of memory registers that make a physical system. Imposing the characteristic properties of physical laws to such an algorithm, i.e. homogeneity, reversibility and isotropy, we will show that the physical laws thus selected are particular algorithms known as cellular automata. Further assumptions regarding maximal simplicity of the algorithm lead to two cellular automata only, that in a suitable regime can be described by Weyl’s dierential equations, lying at the basis of the dynamics of relativistic quantum elds. We will nally discuss how the same cellular automaton can give rise to both Fermionic eld dynamics and to Maxwell’s equations, that rule the dynamics of the electromagnetic eld. We will conclude reviewing the discussion of the relativity principle, that must be suitably adapted to the scenario where space-time is not an elementary notion, through the denition of a change of inertial reference frame, and whose formulation leads to the recovery of the symmetry of Minkowski space-time, identied with Poincar´e’s group. Space-time thus emerges as one of the manifestations of physical laws, rather than the background where they occur, and its features are determined by the dynamics of systems, necessarily equipped with dierential equations that express it. In brief, there is no space-time unless an evolution rule requires it.

Cosmology in f(Q) geometry

The universal character of the gravitational interaction provided by the equivalence principle motivates a geometrical description of gravity. The standard formulation of General Relativity \`a la Einstein attributes gravity to the spacetime curvature, to which we have grown accustomed. However, this perception has masked the fact that two alternative, though equivalent, formulations of General Relativity in flat spacetimes exist, where gravity can be fully ascribed either to torsion or to non-metricity. The latter allows a simpler geometrical formulation of General Relativity that is oblivious to the affine spacetime structure. Generalisations along this line permit to generate teleparallel and symmetric teleparallel theories of gravity with exceptional properties. In this work we explore modified gravity theories based on non-linear extensions of the non-metricity scalar. After presenting some general properties and briefly studying some interesting background cosmologies (including accelerating solutions with relevance for inflation and dark energy), we analyse the behaviour of the cosmological perturbations. Tensor perturbations feature a re-scaling of the corresponding Newton's constant, while vector perturbations do not contribute in the absence of vector sources. In the scalar sector we find two additional propagating modes, hinting that $f(Q)$ theories introduce, at least, two additional degrees of freedom. These scalar modes disappear around maximally symmetric backgrounds because of the appearance of an accidental residual gauge symmetry corresponding to a restricted diffeomorphism. We finally discuss the potential strong coupling problems of these maximally symmetric backgrounds caused by the discontinuity in the number of propagating modes.

Foundations of Finsler Spacetimes from the Observers’ Viewpoint

Physical foundations for relativistic spacetimes are revisited in order to check at what extent Finsler spacetimes lie in their framework. Arguments based on inertial observers (as in the foundations of special relativity and classical mechanics) are shown to correspond with a double linear approximation in the measurement of space and time. While general relativity appears by dropping the first linearization, Finsler spacetimes appear by dropping the second one. The classical Ehlers–Pirani–Schild approach is carefully discussed and shown to be compatible with the Lorentz–Finsler case. The precise mathematical definition of Finsler spacetime is discussed by using the space of observers. Special care is taken in some issues such as the fact that a Lorentz–Finsler metric would be physically measurable only on the causal directions for a cone structure, the implications for models of spacetimes of some apparently innocuous hypotheses on differentiability, or the possibilities of measurement of a varying speed of light.

Masonic symbolism in the context of philosophical anthropology searches

The article is dedicated to the Masonic ideas influence on a symbolism interpretation in anthropology, vision of the Masonic symbolism in Masonic ideas influence on a modern philosophical discourse. The symbolic codes investigation was opening space for a philosophical discourse, human identity and self-equivalence searches. Masons and philosophers of the 20th century had been working on a same cultural and semantic field, with the same cultural, historical and epistemological universals, considering symbols as a priori language and a priori form of learning. The existence archetypes, sense-creating codes search led Masons to the vision that symbols did not contain the final content, but gave a wide field of the interpretation possibilities, were a gnoseological key, a tool for a self-learning and a “super-reality” learning, for the adept’s gnoseological qualities forming. Masonic ideology was based on “ascribing” to the certain objects some special symbolic meaning, on conviction that by means of symbols it was possible to teach laymen the basics of the independent and free learning process. Masonic convictions say that symbol is marking the space-time relations, performing the communicative processes. Philosophers of the 20th century (C. Levi-Strauss, E. Cassirer, N. Berdyaev and others) gave to the symbols meanings of the objective character and of the values, they opened the reality levels, for which a non-symbolic language did not fit. They considered a person to perceive the symbols of the object and not the object itself. Walking a “Masonic path”, these philosophers supposed that symbols were forming the goal-setting senses which could be conceived by civilizations, values, tastes, fashion. So, for people of Modernity, “society” became a symbol of the people’s uniting in the name of the progress and the democracy. Philosophers began looking at the society as at the historical self-realization process, as at the knowledge and self-knowing tool. It can be assumed that “Masonic phenomenon” in European philosophy influenced the scientific search directions forming. The classified masonic discourses gave birth to the thoughts which later transformed into philosophical concepts of the 20th century.

Minimal and maximal lengths from position-dependent non-commutativity

Fring et al (2010 J. Phys. A: Math. Theor. 43 345401) have introduced a new set of noncommutative space-time commutation relations in two space dimensions. It had been shown that any fundamental objects introduced in this space-space noncommutativity are string-like. Taking this result into account, we generalize the seminal work of Fring et al to the case that there is also a maximal length from position-dependent noncommutativity and a minimal momentum arising from generalized versions of Heisenberg’s uncertainty relations. The existence of maximal length is related to the presence of an extra, first order term in particle’s length that provides the basic difference of our analysis with theirs. This maximal length breaks up the well known singularity problem of space time. We establish different representations of this noncommutative space and finally we study some basic and interesting quantum mechanical systems in these new variables.

Spacetimes with different forms of energy–momentum tensor

The object of the present paper is to characterize spacetimes with different types of energy–momentum tensor. At first we consider spacetimes with pseudo symmetric energy–momentum tensor T. We obtain a necessary and sufficient condition for a spacetime with pseudo symmetric energy–momentum tensor to be a pseudo Ricci symmetric spacetime. Next we consider the spacetimes with Codazzi type of energy–momentum tensor and several interesting results are pointed out. Moreover, some results related to perfect fluid spacetimes with different forms of energy–momentum tensors have been obtained. We study spacetimes with quadratic Killing energy–momentum tensor T and show that a GRW spacetime with quadratic Killing energy–momentum tensor is an Einstein space. Finally, we have considered general relativistic spacetimes with semisymmetric energy–momentum tensor and obtained some important results.