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We present a novel solution procedure for initial boundary value problems. The procedure is based on an action principle, in which coordinate maps are included as dynamical degrees of freedom. This reparametrization invariant action is formulated in an abstract parameter space and an energy density scale associated with the space-time coordinates s...
Quantum Space-Time Theory: Fundamentals by Matthew Eric Mackey Stanford and Isabelle Lee Stanford Mackey! Always a work in progress; however, the first version was completed and uploaded on 1/23/2024! Feel free to ask questions/comment here! Quantum Space-Time Theory is the science field of Reality Physics based on Quantum Physics and contains new...
In this study, we aim to investigate the interaction dynamics of a fermion–antifermion (ff) pair within a curved three-dimensional space–time with a non-zero cosmological constant (Λ>0). Our primary goal is to understand the relative motion of this pair by deriving a radial equation set and finding analytical solutions using the covariant many-body...
Reconnections of spatiotemporal optical vortices have been shown to occur between line vortices. Here, we show that reconnections also occur between spatiotemporal loop vortices in optical waves. As optical loop vortices propagate in a media with spatial diffraction and material group velocity dispersion, unique reconnections occur. The birth and d...
The analysis of [T.K. Das, Generalized Shock Solutions for Hydrodynamic Black Hole Accretion, ApJ. 577, 880 (2002)] is here applied to analytically study the General-Relativistic transonic behaviour of generic gravitating viscous accretion objects onto celestial bodies. The sonic points are written; the speed of sound is calculated; the gravitation...
This study develops a framework to evaluate real estate financial risk from three perspectives: internal risk factors, external risk factors, and interconnected risk factors, examining regional space–time differences and dynamic evolution laws across 30 provinces in China. The research finds that (1) interconnected risk factors are key contributors...
Populations of coupled oscillators can exhibit a wide range of complex dynamical behavior, from complete synchronization to chimera and chaotic states. We can, thus, expect complex dynamics to arise in networks of such populations. Here, we analyze the dynamics of networks of populations of heterogeneous mean-field coupled Kuramoto–Sakaguchi oscill...
Modern physics describes the universe in terms of particles, forces, and space-time, yet fundamental gaps remain. Quantum mechanics and general relativity remain incompatible, and the nature of consciousness and intelligence is still unresolved. This paper explores an alternative paradigm: the Computational Aether hypothesis, proposing that reality...
Using recent developments in expressing one-loop partition functions in Euclidean $AdS_2$ space-times in terms of character integrals, we relate the one-loop effective action for a free field theory in $AdS_2$ (comprised of a massless scalar field and a massless Majorana fermion field) to the partition function of the de Alfaro-Fubini-Furlan (DFF)...
A novel short-term time series forecasting scheme based on evolutionary interpolation of Chebyshev polynomials is presented in this paper. The uniqueness of the proposed scheme lies in the higher density of Chebyshev nodes at the ends of the interpolation interval. Thus, the structural representation of the algebraic interpolant closer to the prese...
The possibility of geometrization of the gravitational and electro magnetic fields in 4D Finsler space (the Model of Embedded Spaces -- MES) is investigated. The model postulates a proper metric set of an element of distributed matter and asserts that space-time is a mutual physical embedding of such sets. The simplest MES geometry is constructed (...
In this paper, we show the existence of an invariant minimum speed in space–time by forming the basis of a deformed special relativity so-called symmetrical special relativity (SSR). Such observer-independent minimum speed emerges from Dirac’s large number hypothesis (LNH), which leads us to build SSR-theory. This allows us to understand that the h...
In this paper, we have investigated bound state solutions for a scalar particle described in the space–time of a chiral cosmic string subjected to rotational effects in a Kaluza–Klein theory. We saw that combinations between the parameters that describe the generalized space–time impose upper and lower limits for the radial coordinate leading to we...
The nature of reality has long been debated across physics, philosophy, and theology, yet a truly unified framework remains elusive. Classical physics treats space-time as a passive backdrop, quantum mechanics reveals nonlocal probabilistic behavior, and emergent complexity suggests an intrinsic drive toward higher-order structures. In this paper,...
We extend the Quantum Memory Matrix (QMM) framework, originally developed to reconcile quantum mechanics and general relativity by treating space–time as a dynamic information reservoir, to incorporate the full suite of Standard Model gauge interactions. In this discretized, Planck-scale formulation, each space–time cell possesses a finite-dimensio...
In our investigation, we pioneer the development of geometrically deformed strange stars within the framework of teleparallel gravity theory through gravitational decoupling via the complete geometric deformation (CGD) technique. The significant finding is the precise solution for deformed strange star (SS) models achieved through the vanishing com...
In this work, we obtained exact solutions of Einstein’s field equations for plane symmetric cosmological models by assuming that they admit conformal motion. The space-time geometry of these solutions is found to be nonsingular, non-vacuum and conformally flat. We have shown that in the case of a perfect fluid, these solutions have an energy-moment...
This paper shows that lumped directed-area vectors at edges and dual control volumes required to implement the edge-based discretization can be computed without explicitly defining the dual control volume around each node for triangular and tetrahedral grids. It is a simpler implementation because there is no need to form a dual control volume by c...
The concept of solitons has found its way into various domains of physics, especially in the context of non-linear wave equations and field theory. In this paper, we extend the idea of solitons to the realm of general relativity, proposing the existence of soliton-type space-time defects. These defects are non-singular, localized perturbations in s...
Classical diffusion models rely on continuous field equations to describe energy propagation. However, recent advances in quantum gravity, string theory, and astrophysical observations suggest that energy transport at the Planck scale may be governed by a discrete geometric structure rather than continuous wave-like propagation. This work proposes...
In this article it is shown that the vacuum in general relativity is redundant, since the terms with the contribution of the vacuum cancel each other out. Because of this, general relativity is a classical and no quantum theory, in which the cosmological constant Λ in no way represents the energy density of the vacuum, but a scalar curvature of spa...
span>Transmit antenna selection (TAS) plays a crucial role in improving the performance and spectral efficiency of 5G/6G systems. This study proposes to use the GridSearchCV method for hyperparameter optimization in two supervised learning models, support vector machine (SVM) and K-nearest neighbors (KNN), to optimally select antenna peers based on...
This paper concerns the space–time decay rates of strong solution to a nonconservative compressible two–phase flow model in the whole space R3. Based on the previous temporal decay results, it is shown that the space–time decay rate of k(0 ≤ k ≤ N)–order spatial derivative of the strong solution in weighted Lebesgue space Lγ2 is t−34−k2+γ for any i...
Background
Proteases are essential in various industries due to their unique substrate specificities and robustness in different operational conditions. Bacillus strains consist of a genotype favorable for rapid growth whilst secreting enzymes extracellularly, thereby simplifying recombinant protease production. Despite the widespread use of batch...
This paper presents a parallelizable variant of the well-known Hierarchical Cooperative A* algorithm (HCA*) for the multi-agent path finding (MAPF) problem. In this variant, all agents initially find their shortest paths disregarding the presence of others. This is done using A*. Then an intersection graph (IG) is constructed; each agent is a node...
Space-time separability is commonly assumed in the theoretical description of laser beams. However, recent progresses have demonstrated that this assumption often breaks down for ultrashort realistic pulses, giving rise to spatio-temporal effects that modify both the spatial and temporal characteristics of the laser field. In this work, we introduc...
Poalo Portoghesi's opus can be perceived as segmented, fragmented, where a matrix is formed in the form of a fractal whose parts are a reduced copy of the whole. His creativity is such that it is a matter of a historian, an architect as well as a theoretician, where it is difficult to determine the primacy of dominance of an individual position. Th...
Highly dispersed Pt‐bimetallic sub‐nanometer catalysts are crucial for efficient propane dehydrogenation (PDH), but synthesizing them with cost‐effective Pt precursors is challenging due to Pt's tendency to agglomerate, reducing catalytic activity. This study presents a Cs⁺‐mediated vacancy‐anchoring strategy to fabricate sub‐nanometer Pt‐bimetalli...
Pulsar timing, i.e. the analysis of the arrival times of pulses from a pulsar, is a powerful tool in modern astrophysics. It allows us to measure the time delays of an electromagnetic signal caused by a number of physical processes as the signal propagates from the source to the observer. Joint analysis of an ensemble of pulsars (Pulsar Timing Arra...
This paper proposes a numerical scheme for solving a system of convection-reaction-diffusion equations describing the process of preparing a catalyst on a porous support by the impregnation method. In the case of a considered porous spherical pellet, the equations are defined on an interval, one end of which, associated with the front of the impreg...
Chemical conversion of CO2 is providing an opportunity to mitigate the global warming induced by the overconsumption of fossil fuel. Cu has been regarded as one of the most powerful contenders in catalyzing CO2 conversion, yet the precise manipulation of its surface state and the nearby chemical environment continues to pose a formidable challenge....
In this paper, we present a three-parameter model for the distributions of “dark matter” around local spherically symmetric and static distributions of normal matter, usually referred to as “dark matter halos”. The model is based on the assumption that the spontaneous symmetry breaking mechanism involving the Higgs field in the standard model of el...
Control of cell‐type‐specific gene activation requires the coordinated activity of distal regulatory elements, including enhancers, whose inputs must be temporally integrated. Dysregulation of this regulatory capacity, such as aberrant usage of enhancers, can result in malignant transformation of cells. In this review, we provide an overview of our...
In a previous paper, I described a new way of determining the high-latitude solar rotation rate statistically from space-time maps of polar faculae observed in the 6767 \r{A} continuum by the Michelson Doppler Interferometer (MDI) on the Solar and Heliospheric Observatory (SOHO) Sheeley (2024). Now, I have tested the technique by applying it to sim...
General relativistic Gauss equations for osculating elements for bound orbits under the influence of a perturbing force in an underlying Schwarzschild space-time have been derived in terms of Weierstrass elliptic functions. Thereby, the perturbation forces are restricted to act within the orbital plane only. These equations are analytically solved...
The type IIB matrix model is a promising nonperturbative formulation of superstring theory, which may elucidate the emergence of ( 3 + 1 )-dimensional space-time. However, the partition function is divergent due to the Lorentz symmetry, which is represented by a noncompact group. This divergence has been regularized conventionally by introducing so...
In special relativity space-time coordinates of two different observers are related by Lorentz transformations with magnitude of boost's speed smaller than speed of light. In this paper we give a mathematical representation of superluminal Lorentz transformations describing change of space-time coordinates for observers moving relatively to each ot...
In this paper, we investigate a series of topologically charged exponential traversable wormhole models described by the standard metric form:
where \(0< \alpha < 1\) is the global monopole chare parameter. We focus on the positivity of the energy density across these models, defined by the following functions: (i) \(\mathcal {A}(r)=\exp \left( -\f...
We consider the strong numerical approximation for a stochastic Cahn-Hilliard type nonlinear SPDE driven by space-time white noise on $2$-dimensional torus. We consider its full discretisation with a splitting scheme: a spectral Galerkin scheme in space and Euler scheme in time. We show the convergence with almost spatial rate $\frac{1}{2}$ and $1$...
Background: Warming temperatures add to the global health burden, with profound implications for vulnerable populations including pregnant women and newborns. Low birth weight is a major neonatal health issue in Pakistan leading to neonatal mortality and impaired long-term health. This study assessed the impact of extreme temperatures on low birth...
Background
The aim of this paper was to evaluate the distribution of HIV and TB in Ethiopia during four years (2015-2018) at the district level, considering both spatial and temporal patterns.
Methods
Consolidated data on the count of TB case notifications and the number of patients with HIV for four years, 2015-2018, were provided by the Ethiopia...
This is a translation of the Introduction and the second part of three chapters of my book, Thoughts and Behaviour on ‘Global Relations’ (Koyo Shobo, 2024). The first one was originally published in 2006, in Norihisa Yamashita ed., On Empire (Kodansha Sensho Metier). The second was originally published in 2016, in Norihisa Yamashita, Hiroaki Ataka,...
The increase of ground deformation, seismicity, and gas emission is underlining a remarkable unrest at Campi Flegrei caldera. The direct involvement of magma has been invoked to explain the deformation and space/time changes of velocity anomalies at shallow crustal depths. Here, we show that detailed imaging of seismicity, improved by phase detecti...
The type IIB matrix model is conjectured to describe superstring theory nonperturbatively in terms of ten $N \times N$ bosonic traceless Hermitian matrices $A_\mu$ ($\mu=0, \ldots , 9$), whose eigenvalues correspond to $(9+1)$-dimensional space-time. Quite often, this model has been investigated in its Euclidean version, which is well defined altho...
This paper presents an in-depth theoretical analysis of the orientation selectivity properties of simple cells and complex cells, that can be well modelled by the generalized Gaussian derivative model for visual receptive fields, with the purely spatial component of the receptive fields determined by oriented affine Gaussian derivatives for differe...
The integrated modulation of radiation and scattering provides an unprecedented opportunity to reduce the number of electromagnetic (EM) apertures in the platform while simultaneously enhancing communication and stealth performance. Nevertheless, achieving full‐polarization, arbitrary amplitude, and phase modulation of radiation scattering remains...
A bstract
We show that the Ward identities of a Carrollian CFT stress tensor at null infinity reproduce the leading and subleading soft graviton theorems for massless scattering in the bulk. We deduce the expressions of the stress tensor components in terms of the bulk radiative modes, and these components turn out to be local at $$ \mathcal{I} $$...
Spatio-temporal aspect is the most useful aspect of crime prevention as it is patterned and predictable. This study is mainly conducted to explore the spatio-temporal hotspots of burglary and to test whether spaces of burglary are constrained by time in Ahmednagar city. The temporal hotspots are identified by their frequency in hours. Spatial hotsp...
The self-catalytic branching Brownian motions (SBBM) are extensions of the classical one-dimensional branching Brownian motions by incorporating pairwise branchings catalyzed by the intersection local times of the particle pairs. These processes naturally arise as the moment duals of certain reaction-diffusion equations perturbed by multiplicative...
This paper investigates the evolving role of virtual reality (VR) in contemporary art, focusing on its aesthetic principles and transformative potential. By examining VR's immersive qualities, interactive elements, and historical development, the study examines how it reshapes artistic practices and audience engagement. Drawing parallels to expande...
This article focuses on characterizing warped product manifolds through the flatness and the symmetry of the concircular curvature tensor. It is proved that the factor manifolds of a concircularly-flat warped product manifold have constant sectional curvatures as well as they are concircularly-flat. It is shown that in a concircularly-symmetric war...
Polymers of intrinsic microporosity porosity (PIMs) represent a versatile class of materials first discovered over 20 years ago. Despite extensive studies resulting in the optimization of their synthesis, the underlying reaction kinetics have never been the focus of research. This study presents a detailed examination of the reaction kinetics invol...
This study introduces a novel space-time fractional diffusion equation with the capacity to model a diverse spectrum of diffusion processes. The equation incorporates Caputo-type time derivatives with an arbitrary order \(\beta\) and introduces a spatial-fractional operator known as the fractional Bessel operator. The fundamental solution of this e...
In order to study the influence of ventilation parameters on gas movement in large sections of highway tunnels, a mathematical model of gas movement in tunnels is established based on the Yijin Expressway’s Kahaluo No. 1 three-lane tunnel project in Sichuan Province, by using Fluent numerical simulation software to simulate gas tunnel construction....
The higher dimensional Fokas equation is the integrable expansion of the Davey-Stewartson and Kadomtsev-Petviashvili equations. In wave theory, the Fokas model plays a crucial role in explaining the physical phenomena of waves both inside and outside of water. The (4+1)-dimensional fractional-order Fokas equation is the subject of this article. Two...
Space-time methods promise more efficient time-domain simulations, in particular of electrical machines. However, most approaches require the motion to be known in advance so that it can be included in the space-time mesh. To overcome this problem, this paper proposes to use the well-known air-gap element for the rotor-stator coupling of an isogeom...
The practically insurmountable diculties of the interconversion between space and time are discussed here when this interconversion is not posed in mathematical terms, but in real physical terms. The supposed symmetry between space and time of the space-time continuum is also questioned in the same real physical terms.
Background
The success of the theories of special and general relativity in describing localised phenomena, such as objects undergoing high speed motion or located in gravitational fields, needs no further elaboration. However, when applied to the evolution of the universe several problems arise which can require an additional model, e.g., inflatio...
The purpose of the article is to analyze an accurate numerical technique to solve a space-time fractional-order Fisher equation in the Caputo sense. For this purpose, the spectral collocation technique is used, which is based on the Vieta–Lucas approximation. By using the properties of Vieta–Lucas polynomials, this technique reduces the nonlinear e...
Multiplication over binary fields is a crucial operation in quantum algorithms designed to solve the discrete logarithm problem for elliptic curve defined over $GF(2^n)$. In this paper, we present an algorithm for constructing quantum circuits that perform multiplication over $GF(2^n)$ with $\mathcal{O}(n^{\log_2(3)})$ Toffoli gates. We propose a v...
This study aims to investigate dispersion engineering mechanisms within unilateral and bilateral metasurface-based leaky-wave antennas, presenting methodologies focused on space-time modulation of impedance boundary conditions. Utilizing the generalized framework based on the Floquet-wave expansion method, the research precisely investigates the ef...
We investigate how the gravitational field generated by a four-dimensional electrovacuum cosmological space–time influences the dynamics of fermionic fields governed by the Dirac equation, while also considering the effects of topology. We derive the radial wave equation corresponding to the relativistic Dirac equation and obtain analytical solutio...
This paper proposes a novel 5D spacetime metric incorporating an additional time-like dimension, tx, to extend the traditional 4D framework of general relativity. The metric introduces two dynamical coupling functions, A(t, tx) and B(t, tx), which govern interactions between the traditional time dimension t and the new dimension tx. We analyze the...
In the framework of f(R,T) gravity proposed by Harko et al. spatially homogeneous and anisotropic Bianchi type -〖VI〗_0 cosmological model is considered when the source for energy momentum tensor is a bulk viscous fluid containing one dimensional cosmic string. To solve the field equations completely, we have considered three different cases: (i) th...
The celebrated theory of general relativity has inspired research on optical simulations using artificial microstructures to mimic curved space–times. The gravitational lensing that bends light close to large mass concentrations is one of the most fascinating predictions by general relativity. Herein, an optical lens is utilized to emulate the grav...
The measurement of momentum correlations of identical pions serves as a fundamental tool for probing the space-time properties of the particle emitting source created in high-energy collisions. Recent experimental results have shown that, in pp collisions, the size of the one-dimensional primordial source depends on the transverse mass (\mt) of had...
The arXiv preprint 2411.15164v1 \cite{Li:2024ltx} discusses how a weak Schwarzschild spacetime modifies Feynman diagram calculations and the governing equations of scalar and spinor particles. This short review offers an extended analysis on concerning points involving massless particles and limitations of weak-field approximation. Written for the...
As public concern for maritime safety grows, there is a pressing need to delve deeper into the root causes of maritime accidents and develop effective preventive strategies. Spatial-temporal analysis stands out as a powerful approach to pinpointing accident hot spots. While previous research has shed light on the spatial aspects of these incidents,...
We construct and analyse wormhole solutions in quantised space-time. The field equations are constructed from the deformed wormhole metric in the proper reference frame using tetrads. The spatial geometry of the wormhole is analysed in kappa space-time. Further, modifications to the conditions that ensure traversibility of the wormhole are studied...
In this paper, cosmic distance duality relation is probed without considering any background cosmological model. The only \textit{a priori} assumption is that the Universe is described by the Friedmann-Lema$\hat{i}$tre-Robertson-Walker (FLRW) metric The strong gravitational lensing (SGL) data is used to construct the dimensionless co-moving distanc...
Based on the economic importance of magnesium chloride for both industrial and domestic applications, this article have showed that apart from the use of various extraction technologies for magnesium chloride production, the economic viable product can also be produced via neutralization reaction between naturally occurring magnesium oxide and hydr...
My corpus-based research examines demonstratives in Norton Sound Kotlik Yup'ik and how the abundant semantics of the demonstrative system influences its use in temporal reference and discourse cohesion. Central Alaskan Yup'ik is purported to have one of the world's most complex spatial demonstrative systems with several dozen reflexes (Miyaoka, 201...
We are concerned with the "transfer of regularity" phenomenon for the incompressible Navier--Stokes Equations (NSE) in dimension $n \geq 3$; that is, the strong solutions of NSE on $\mathbb{R}^n$ can be nicely approximated by those on sufficiently large domains $\Omega \subset \mathbb{R}^n$ under the no-slip boundary condition. Based on the space-t...
Holography=holomorphy principle allows to solve the extremely nonlinear partial differential equations for the space-time surfaces exactly by reducing them to algebraic equations involving an identically vanishing contraction of two holomorphic tensors of different types. In this article, space-time counterparts for elliptic curves and doubly perio...
In this work we investigate the effect of complexity factor on the formation of photon spheres for spherically symmetric compact objects. The complexity factor obtained from the orthogonal splitting of the Riemann curvature tensor connects the geometric attributes of a compact spherically symmetric gravitating object with its matter inhomogeneity a...
Using the method of paracontrolled distributions, we show the local well-posedness of an additive-noise approximation to the fluctuating hydrodynamics of the Keller–Segel model on the two-dimensional torus. Our approximation is a non-linear, non-local, parabolic-elliptic stochastic PDE with an irregular, heterogeneous space-time noise. As a consequ...