Field In Space Research Articles

Color-kinematics duality for nonlinear sigma models with nonsymmetric cosets

We propose an extension of the color-kinematics duality for nonlinear sigma models with nonymmetric cosets. The role of color is replaced with curvatures in field space. The duality between curvature and kinematics allows for a new double copy: the double copy of the nonlinear sigma model for nonsymmetric cosets is the general Galileon theory. We provide evidence for this new double copy of geometry. Published by the American Physical Society 2024

Quotient quiver subtraction

We develop the diagrammatic technique of quiver subtraction to facilitate the identification and evaluation of the SU(n) hyper-Kähler quotient (HKQ) of the Coulomb branch of a 3dN=4 unitary quiver theory. The target quivers are drawn from a wide range of theories, typically classified as “good” or “ugly”, which satisfy identified selection criteria. Our subtraction procedure uses quotient quivers that are “bad”, differing thereby from quiver subtractions based on Kraft-Procesi transitions. The simple diagrammatic procedure identifies one or more resultant quivers, the union of whose Coulomb branches corresponds to the desired HKQ. Examples include quivers whose Coulomb branches are moduli spaces of free fields, closures of nilpotent orbits of classical and exceptional type, and slices in the affine Grassmanian. We calculate the Hilbert Series and Highest Weight Generating functions for HKQ examples of low rank. For certain families of quivers, we are able to conjecture HWGs for arbitrary rank. We examine the commutation relations between quotient quiver subtraction and other diagrammatic techniques, such as Kraft-Procesi transitions, quiver folding, and discrete quotients.

Constraining dark matter from strong phase transitions in a U1Lμ−Lτ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \ extrm{U}{(1)}_{L_{\\mu }-{L}_{\ au }} $$\\end{document} model: implications for neutrino masses and muon g − 2

In this paper, we study a non-minimal gauged U1Lμ−Lτ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \ extrm{U}{(1)}_{L_{\\mu }-{L}_{\ au }} $$\\end{document} model, where we add two complex singlet scalars, three right-handed Majorana neutrinos (RHN), and a vector-like dark fermion to the Standard Model (SM), all non-trivially charged under the extra gauge symmetry. The model offers an easy resolution to the muon (g – 2) anomaly, which fixes the scale of spontaneous symmetry breaking. Furthermore, the two-zero minor structure in the RHN mass matrix provides successful predictions for neutrino oscillation parameters, including the Dirac phase. The extended scalar sector can easily induce first-order phase transitions. We identify all possible phase transition patterns in the three-dimensional field space. We quantify the associated gravitational waves from the sound wave source and demonstrate that the signatures can be observed in future space-based experiments. We find that strong first-order phase transitions require large values of scalar quartic couplings which constrain the scalar dark matter (DM) relic density to a maximum of 10−2 and 10−5 when we consider the DM direct detection bound. Nonetheless, the model successfully explains the DM relic density via contribution from the vector-like dark fermion. We show the allowed range of the model parameters that can address all the beyond SM issues targeted in this study.

Free Reflection Multiarrangements and Quasi-Invariants

Abstract To a complex reflection arrangement with an invariant multiplicity function one can relate the space of logarithmic vector fields and the space of quasi-invariants, which are both modules over invariant polynomials. We establish a close relation between these modules. Berest–Chalykh freeness results for the module of quasi-invariants lead to new free complex reflection multiarrangements. Saito’s primitive derivative gives a linear map between certain spaces of quasi-invariants. We also establish a close relation between non-homogeneous quasi-invariants for root systems and logarithmic vector fields for the extended Catalan arrangements. As an application, we prove the freeness of Catalan arrangements corresponding to the non-reduced root system $BC_{N}$.

Explicit A Posteriori Error Representation for Variational Problems and Application to TV-Minimization

AbstractIn this paper, we propose a general approach for explicit a posteriori error representation for convex minimization problems using basic convex duality relations. Exploiting discrete orthogonality relations in the space of element-wise constant vector fields as well as a discrete integration-by-parts formula between the Crouzeix–Raviart and the Raviart–Thomas element, all convex duality relations are transferred to a discrete level, making the explicit a posteriori error representation –initially based on continuous arguments only– practicable from a numerical point of view. In addition, we provide a generalized Marini formula that determines a discrete primal solution in terms of a given discrete dual solution. We benchmark all these concepts via the Rudin–Osher–Fatemi model. This leads to an adaptive algorithm that yields a (quasi-optimal) linear convergence rate.

Asymptotic Behavior of Saxion–Axion System in Stringy Quintessence Model

AbstractThe late time behavior of the slow‐roll parameter in the stringy quintessence model is studied when axion as well as saxion are allowed to move. Even though the potential is independent of the axion at tree level, the axion can move through its coupling to the saxion and the background geometry. Then the contributions of the axion kinetic energy to the slow‐roll parameter and the vacuum energy density are not negligible when the slow‐roll approximation does not hold. As the dimension of the field space is doubled, the fixed point at which the time variation of the slow‐roll parameter vanishes is not always stable. It is found that the fixed point in the saxion–axion system is at most partially stable, in particular when the volume modulus and the axio‐dilaton, the essential ingredients of the string compactification, are taken into account. It seems that as more saxion–axion pairs are considered, achieving the stability of the fixed point becomes difficult.

Remarks on 2D quantum cosmology

We consider two-dimensional quantum gravity endowed with a positive cosmological constant and coupled to a conformal field theory of large and positive central charge. We study cosmological properties at the classical and quantum level. We provide a complete ADM analysis of the classical phase space, revealing a family of either bouncing or big bang/crunch type cosmologies. At the quantum level, we solve the Wheeler-DeWitt equation exactly. In the semiclassical limit, we link the Wheeler-DeWitt state space to the classical phase space. Wavefunctionals of the Hartle-Hawking and Vilenkin type are identified, and we uncover a quantum version of the bouncing spacetime. We retrieve the Hartle-Hawking wavefunction from the disk path integral of timelike Liouville theory. To do so, we must select a particular contour in the space of complexified fields. The quantum information content of the big bang cosmology is discussed, and contrasted with the de Sitter horizon entropy as computed by a gravitational path integral over the two-sphere.

Influence of Campus Outdoor Spaces on Students Behavior: Enhancing Social Interaction and Learning at An-Najah University

This study examines how the physical features of university campus outdoor spaces affect student behavior, aiming to promote social interaction and improve learning outcomes. Two central questions guide the research: how student movements relate to open space features, and how campus layout influences student circulation and interaction. By employing a mixed-method approach, including field observations and space syntax analysis, five areas at An-Najah University Campus are studied. The findings highlight the importance of these insights in urban design and planning, especially for teaching staff, students, and visitors. Results indicate that spatial layout and physical features significantly affect space usage, with students favoring areas with seating, shade, and social opportunities, adapting to informal setups when formal options are limited. Visibility is key, with students favoring spaces offering maximum visibility for seating. This understanding informs architects and planners in creating engaging campus environments for social interaction and learning.

Analytic bounds on late-time axion-scalar cosmologies

The cosmological dynamics of multiple scalar/pseudoscalar fields are difficult to solve, especially when the field-space metric is curved. This presents a challenge in determining whether a given model can support cosmic acceleration, without solving for the on-shell solution. In this work, we present bounds on late-time FLRW-cosmologies in classes of theories that involve arbitrary numbers of scalar and pseudoscalar fields coupled both kinetically (leading to a curved field space metric) and through scalar potentials. Such bounds are proven analytically, independently of initial conditions, with no approximation in the field equations and without referring to explicit solutions. Besides their broad applications to cosmological model building, our bounds can be applied to studying asymptotic cosmologies of certain classes of string compactifications.

STRUCTURAL AND SEMANTIC ORIGINALITY OF THE SEMANTIC FIELD ‟POWER” IN VLADIMIR MAKSIMOV’S NOVEL ‟TO LOOK INTO THE ABYSS”

The article characterises the semantic field ‟Power” in the novel by the famous Russian prose writer of the 2nd half of the 20th century, Vladimir Maksimov (1930–1995). The purpose of the study is a comprehensive analysis of the structural and semantic features of the field, determination of the originality of the textual functioning of its core components, which are the semantic dominants of the work, actively involved in the organisation of the narrative, in the artistic depiction of historical events and the creation of images of literary characters. The theoretical concepts of the semantic field and semantic space of the text, which unites its conceptual, denotative and emotive meanings, are defined. Linguistic modelling of the field structure is based on the principles of discourse analysis of the text and is determined by the specific linguistic personality of the writer, genre-stylistic and plot-compositional features of the work. Characteristic of component composition of the field, its core, centre and periphery, microfields is given. Semantic connections and intersections of field components are determined with contextual synonymy and antonymy revealed. The core of the field includes the key lexemes “power”, “strength”, “leader”, “will”. The semantic field unites five microfields: the central part of the field structure includes the microfields ‟White-Guard Power of Alexander Kolchak” and ‟Soviet Power of Vladimir Lenin”; the peripheral zone includes the microfields ‟Power of Social Elements”, ‟Military Force of Foreign Intervention” and ‟Power of Selfless and unselfish Love”. The semantic dominants of the text, being the key components of the field, contribute to the dynamics of the narrative, create an artistic chronotope, reflect the author’s position, and convey the bright features of the writer’s linguistic personality.

Capacity of entanglement and volume law

We investigate various aspects of capacity of entanglement in certain setups whose entanglement entropy becomes extensive and obeys a volume law. In particular, considering geometric decomposition of the Hilbert space, we study this measure both in the vacuum state of a family of non-local scalar theories and also in the squeezed states of a local scalar theory. We also evaluate field space capacity of entanglement between interacting scalar field theories. We present both analytical and numerical evidences for the volume law scaling of this quantity in different setups and discuss how these results are consistent with the behavior of other entanglement measures including Renyi entropies. Our study reveals some generic properties of the capacity of entanglement and the corresponding reduced density matrix in the specific regimes of the parameter space. Finally, by comparing entanglement entropy and capacity of entanglement, we discuss some implications of our results on the existence of consistent holographic duals for the models in question.

Moduli dynamics in effective nested warped geometry in four dimensions and some cosmological implications

We analyze the effective four-dimensional dynamics of the extra-dimensional moduli fields in curved braneworlds having nested warping, with particular emphasis on the doubly warped model which is interesting in the light of current collider constraints on the mass of the Kaluza-Klein graviton. The presence of a non-zero brane cosmological constant (Ω) naturally induces an effective moduli potential in the four-dimensional action, which shows distinct features in dS (Ω > 0) and AdS (Ω < 0) branches. For the observationally interesting case of dS 4-branes, a metastable minimum in the potential arises along the first modulus, with no minima along the higher moduli. The underlying nested geometry also leads to interesting separable forms of the non-canonical kinetic terms in the Einstein frame, where the brane curvature directly impacts the kinetic properties of only the first modulus. The non-canonicity of the scenario has been illustrated via an explicit computation of the field space curvature. We subsequently explore the ability of curved multiply warped geometries to drive inflation with an in-built exit mechanism, by considering predominant slow roll along each modular direction on a case-by-case basis. We find slow roll on top of the metastable plateau along the first modular direction to be the most viable scenario, with the higher-dimensional moduli parametrically tuning the height of the potential without significant impact on the inflationary observables. On the other hand, while slow roll along the higher moduli can successfully inflate the background and eventually lead to an exit, consistency with observations seemingly requires unphysical hierarchies among the extra-dimensional radii, thus disfavouring such scenarios.

Hidden symmetries of power-law inflation

Abstract A scalar field with an exponential potential has been proposed as a model of inflation (called power-law inflation). Although it admits an exact solution, the integrability of the system has not been shown. We uncover the hidden symmetries behind the system by utilizing the Eisenhart lift of field theories. We find that a conformal Killing vector field in the field space exists only for a particular combination of exponential functions that includes a single exponential potential. This implies the existence of additional conserved quantity and explains the integrability of the system.

Magnetic field enhanced laser absorption on a metallic surface incorporated with shape-dependent nanostructures

Abstract This communication proposes an analytical model to investigate the nanoparticle-based nonlinear absorption phenomenon associated with an obliquely incident p-polarized laser beam on a metallic surface. In this scheme, the surface is ingrained with noble-metal spherical nanoparticles and cylindrical nanoparticles in the presence of an external static magnetic field. The absorption of laser energy in the presence of nanoparticles (NPs) is attributed to surface plasmon resonance and enhanced magnetic-field effects. The absorption phenomenon is significantly enhanced by the incorporation of nanostructures and a magnetic field. The ellipticity characterizing parameter, which significantly influences the resonant frequency of different nanometric structures, has also been analysed and discussed. The effects of varying the magnetic field intensity, incident angle, size, and spacing of the NP were examined to determine their influence on the anomalous absorption of the laser. Furthermore, a direct dependency was found between the absorption coefficient and transmission coefficient of the incident laser, as well as the dimensions of the NPs. Several applications have direct relevance to this study, including biosensors such as DNA sensors and immunosensors, photothermal therapy, photoacoustic imaging, optoelectronic devices, solar cells, and surface-enhanced Raman spectroscopy.

Variational aspect and kinetic theory of locally conformal dynamics

Abstract We present the locally conformal generalization of the Euler–Lagrange equations. We determine the dual space of the LCS Hamiltonian vector fields. Within this dual space, we formulate the Lie–Poisson equation that governs the kinetic motion of Hamiltonian systems in the context of local conformality. By expressing the Lie–Poisson dynamics in terms of density functions, we derive locally conformal Vlasov dynamics. In addition, we outline a geometric pathway that connects LCS Hamiltonian particle motion to locally conformal kinetic motion.

Geometry of N=2 Minkowski vacua of gauged N=2 supergravity theories in four dimensions

Gauging isometries of four-dimensional N=2 supergravity theories yields an N=2 supersymmetric theory with a scalar potential. In this paper, we study the well-known constraints for four-dimensional N=2 Minkowski vacua of such theories. We propose that classically a projective special Kähler submanifold of the projective Kähler target space of the ungauged theory describes the moduli space of the complex scalar fields of massless vector multiplets for N=2 Minkowski vacua configurations, which then receives quantum corrections from integrating out massive fields. Subloci of projective special Kähler manifolds appear as supersymmetric flux vacua in the context of type IIB Calabi–Yau threefold compactifications with background fluxes as well. While these flux vacua equations arise from the critical locus of an N=1 superpotential, we show that these equations can also be obtained from the N=2 supersymmetric Minkowski vacuum equations of gauged N=2 supergravity theories upon gauging suitable isometries in the semiclassical universal hypermultiplet sector of type IIB string Calabi–Yau threefold compactifications. Thus, we give an intrinsic N=2 supersymmetric interpretation to the flux vacua equations. Published by the American Physical Society 2024

Sl(2,C)×D symmetry and conformal primary basis for massless fields

Alternative to the embedding formalism, we provide a group theoretic approach to the conformal primary basis for the massless field with arbitrary helicity. To this end, we first point out that sl(2,C) isometry gets enhanced to sl(2,C)×D symmetry for the solution space of the massless field with D the bulk dilatation. Then, associated with sl(2,C)×D symmetry, we introduce the novel quadratic Casimirs and relevant tensor/spinor fields to derive two explicit constraints on the bulk dilatation and sl(2,C) Casimirs. With this, we further argue that the candidate conformal primary basis can be constructed out of the infinite tower of the descendants of the left and right highest (lowest) conformal primary wave function of sl(2,C) Lie algebra, and the corresponding celestial conformal weights are determined by the bulk scaling dimension through solving out the exact on-shell conformal primary wave functions, where on top of the two kinds of familiar-looking on-shell conformal primary wave functions, we also obtain another set of independent on-shell conformal primary wave functions for the massless field with helicity |s|≥1. In passing, we also develop the relationship between the four-dimensional Lorentz Lie algebra and two-dimensional conformal Lie algebra from scratch, and present an explicit derivation for the two important properties associated with the conformal primary wave functions. Published by the American Physical Society 2024

Контракции калибровочных групп и спонтанное нарушение симметрии

Contractions of gauge models with orthogonal Cayley-Klein groups SO(2; ϵ), SO(3; ϵ), unitary groups SU(2; ϵ) as gauge groups are studied. In the limit of zero contraction parameters, orthogonal groups are isomorphic to the nonsemisimple Euclidean and Newton groups of the corresponding dimension, and the spaces of matter fields become fibered spaces with a degenerate metric. Particular attention is paid to the coordination of spontaneous symmetry breaking with the group contraction procedure. It is shown that contracted gauge theories describe the same set of fields with the same masses as theories with the original simple groups, if the chosen vacuum in the corresponding limit belonged to the base of the fibered space of matter fields. Lagrangians of the models depending on the contraction parameters are obtained, which makes it possible to trace the order of zeroing of terms in the Lagrangians as the contraction parameters tend to zero.

Bird Habitat Suitability Analysis of The New City Centre Gede Bage Bandung Using Landscape Metrics

Abstract One focus of landscape ecology studies is the study of landscape patterns. Understanding the landscape patterns can help to find suitable habitat for the development or restoration of wildlife habitats, which can partly be expressed quantitatively with measurable or computable indicators by Geographic Information System, i.e. landscape metrics. This paper aims to analyze suitable habitat for bird habitat in The New City Centre in Gede Bage Bandung using statistical relationships between the occurrence of birds and the landscape pattern. Our study focus on habitat for Javan Pond Heron (A. speciosa) and Cattle Egret (B. ibis), two bird species which has been lived since 1970 in Ranca Bayawak Village inside The New City Centre Gede Bage Bandung. This study using landscape metrics software FRAGSTAT 4.2, parameter characterising landscape pattern were determined for the UTM 4 km x 4 km cells covering the whole of The New City Centre Gede Bage Bandung. The characteristic bird habitat define based on three types of landscape pattern : built-up areas, green spaces and water bodies. The study results based on statistical calculations found green spaces landscape metrics especially paddy field, forest and green open spaces are suitable for bird habitat, the type of patch that has the second largest patch size from total area. From statistical calculations also known built-up areas landscape metrics has the highest probability of fragmentation and the highest edge effect as a result of The New City Centre Gede Bage Bandung development.

An optimized MOPSA algorithm for highly accurate deterministic lateral displacement microfluidic sorting chip design

Abstract Deterministic lateral displacement (DLD) sorting is a passive sorting technology. Due to the advantages of small volume and high accuracy, the DLD devices have been used in many applications. The critical diameter (Dc) value of the DLD device depends on the geometric structure of the internal post array. However, the existing empirical formula cannot match all types of post-arrays. Achieving the desired Dc value typically involves multiple iterative processes, leading to increased labor and time costs. In this paper, we propose an optimized trajectory prediction algorithm based on the original MOPSA, which considers the impact of fluidic pressure on particle trajectories. The method is to stretch the 2D physical field space into 3D, the particle expands from a 2D circle into a 3D ball on the pressure analysis. The net pressure on the particle is calculated, and the displacement of the particle is predicted by combining Newton’s second law and the displacement formula. A DLD device with Dc=10.6 μm was designed using this optimized algorithm and fabricated. It is verified by separation of 10 μm and 11 μm polystyrene particles. The test results were consistent with the simulation results. Compared with the empirical formula and the original MOPSA, this optimized algorithm can improve the prediction accuracy of particle trajectories in DLD devices.