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In Gepner's pioneering work, the requirement that leads to a model having the desired N = 1 Spacetime supersymmetry and E (8) × E (6) Gauge symmetry was the requirement that the spacetime symmetry is compatible with modular invariance. In this work we show that the requirement for the simultaneous fulfillment of mutual locality of the left-moving vertices of physical states with the space-time symmetry generators and of right-moving vertices with generators of E (8) × E (6) -gauge symmetry, which arises after some special reduction together with the requirement of mutual locality of complete (left-right) vertices of physical states among themselves leads to the same Gepner models. [ABSTRACT FROM AUTHOR]

In this manuscript, we investigate the properties of Casimir wormholes within the framework of extended teleparallel gravity, incorporating the Generalized Uncertainty Principle. Both the Casimir effect and the Generalized Uncertainty Principle (GUP) originate from the concept of a fundamental minimum length. Our analysis explores the geometric and physical traits of these wormholes, examining two distinct GUP constructions namely the Kempf, Mangano, and Mann (KMM) model and the Detournay, Gabriel, and Spindel (DGS) model and their corresponding equations of state. We find that the resulting wormhole solutions exhibit anisotropic effects and violate the null energy condition, implying the presence of exotic fluid. By employing volume integral techniques, we compute the quantity of exotic fluid, providing new insights into the nature of these wormholes. Our study sheds light on the implications of GUP-corrected Casimir wormholes for our understanding of gravity and the structure of spacetime. [ABSTRACT FROM AUTHOR]

In this paper, we consider the Schwarzschild-Tangherlini black hole to investigate the process of scalar wave scattering by the black hole in a spacetime of (d + 1) dimensions and also with the generalized uncertainty principle (GUP). In this scenario, we analytically determine the phase shift and explore the effect of extra dimensions by calculating the differential scattering and absorption cross-section by applying the partial wave method at low and high-frequency limits. We show at high dimensions that the absorption is not zero as the mass parameter approaches zero. [ABSTRACT FROM AUTHOR]

Charged-flat black holes in the Rényi extended phase space demonstrate phase structures akin to those of a van der Waals fluid in four-dimensional spacetime and mirror the behaviors of Reissner-Nordstrom-Anti-de-Sitter black holes within the standard Gibbs-Boltzmann extended phase space. This study delves into the dynamics of states initially positioned within the unstable spinodal region of the phase space associated with the charged-flat black hole when subjected to time-periodic thermal perturbations. Our analysis based on the Mel'nikov method reveals that chaos emerges when the δ parameter surpasses a critical threshold, δ c. This critical quantity is dependent on the black hole charge; notably, a larger value of Q impedes the onset of chaos. Furthermore, we examine the effects of space-periodic thermal perturbations on its equilibrium state and find that chaos invariably occurs, irrespective of the perturbation amplitude. Hence, the chaotic dynamics observed in the analysis of charged-flat black holes under Rényi statistics exhibit resemblances to those of asymptotically AdS-charged black holes investigated via the Gibbs-Boltzmann formalism. This serves as yet another example of a potential and significant connection between the cosmological constant and the nonextensivity Rényi parameter. [ABSTRACT FROM AUTHOR]

We study the one-loop effective action of the higher-spin gauge theory induced by the IKKT matrix model on a M 1 , 3 × K background, where M 1 , 3 is an FLRW cosmological spacetime brane and K are compact fuzzy extra dimensions. In particular, we show that all non-abelian (hs -valued) gauge fields in this model acquire mass via quantum effects, thus avoiding no-go theorems. This leads to a massive non-abelian quantum hs -Yang-Mills theory, whose detailed structure depends on K. The stabilization of K at one loop is understood as a result of the coupling between K and the U (1) -flux bundle on space-time. This flux stabilization induces the KK scale into the N = 4 SYM sector of the model, which break superconformal symmetry. [ABSTRACT FROM AUTHOR]

We have discovered two unconstrained forms of free Lagrangian for continuous spin(CS) theory in arbitrary flat spacetime dimension for bosonic case. These Lagrangians, unlike that by Schuster and Toro, do not include delta functions and are conventional. The first form consists of five kinds of totally symmetric helicity fields and one kind of gauge parameter. By introducing auxiliary creation and annihilation operators, each is combined into a state vector in Fock space, including all ranks one by one. The Lagrangian imposes no constraints, such as trace conditions, on these fields or the gauge parameter field. Additionally, the Lagrangian does not contain higher-order derivative terms. In the limit as CS parameter μ approaches zero, it naturally reproduces a Lagrangian for helicity fields in higher spin(HS) theory, known as unconstrained quartet formulation. Permitting third-order derivatives, we also obtain the second unconstrained form of Lagrangian that can be written in terms of three kinds of fields, including μ , similar to the formulation by Francia and Sagnotti. Partial gauge fixing and partial use of equations of motion (EOM) on this Lagrangian yield a Fronsdal-like Lagrangian with a single double-traceless field, including μ. By imposing further gauge fixing on the field in the EOM with respect to divergence and trace, we confirm the reproduction of the modified Wigner equations already known in literature. [ABSTRACT FROM AUTHOR]

Spacetime singularity is not observed directly as it is covered by event horizon. Naked singularities may be formed due to gravitational collapse without an event horizon. Therefore, cosmic censorship conjecture entails advanced ascertainment. Recently, Joshi et al. have discovered a naked singularity solution (known as JMN naked singularity), which emerges from the dynamical gravitational collapse of a massive matter cloud. Since several studies are needed to know more extra characteristics that may help to test cosmic censorship conjecture in general relativity, therefore, we thought it is pertinent to study the deflection of massive particles by the naked singularity. We shall examine massive particles paths and deflection angles near naked singularities in this research. To get the deflection angle, we employ the Gauss-Bonet technique and the Rindler-Ishak method. The results of the two procedures are compared in detail. [ABSTRACT FROM AUTHOR]

In this manuscript, we study the relativistic dynamics of fermions and vector bosons within a (2+1)-dimensional magnetized space-time. We consider the Bonnor-Melvin magnetic space-time, characterized by a homogeneous magnetic field aligned along the symmetry axis and a non-zero cosmological constant. This space-time background, featuring cylindrical symmetry, retains the invariance of quantum field dynamics under Lorentz boosts along the z -direction. This enables us to explore (2+1)-dimensional realms, where the associated 2+1-dimensional spacetime background is recognized as the Bonnor-Melvin magnetic 2+1+0-brane solution within the framework of gravity coupled with nonlinear electrodynamics. We seek exact solutions for relativistic fermions and vector bosons within this space-time background. We have managed to derive the radial wave equations in both instances, securing precise eigenvalue solutions devoid of any approximations. Our findings extend seamlessly to massless fermions and vector bosons, ensuring generality. Moreover, we observe that the ground state energy of massless vector bosons (photons) within the examined space-time background is unequivocally zero. [ABSTRACT FROM AUTHOR]

In this paper, our focus is on investigating the impact of cosmological constant on relativistic quantum systems comprising spin-0 scalar particles. Our analysis centers around the Klein-Gordon equation, and we obtain both approximate and exact analytical solutions for spin-0 particles of the quantum system. Afterwards, we explore quantum oscillator fields by considering the Klein-Gordon oscillator within the same space-time characterized by a cosmological constant. We obtain an approximate expression for the energy eigenvalue of the oscillator fields. In fact, the energy spectra in both scenarios are examined and show the influences of the cosmological constant and geometry's topology. Our investigation is situated within the context of a magnetic universe-a four-dimensional cosmological space-time recognized as the Bonnor-Melvin universe. [ABSTRACT FROM AUTHOR]

We present local nilpotent fermionic symmetry with a vector-spinor as its gauge field in D = 2 + 2 space-time dimensions. Our field-content is (A μ I , ψ μ I , χ I) , where I = 1 , 2 , ⋯ , g ≡ dim G is the adjoint-index of a gauge group G , while ψ μ I and χ I are Majorana spinors. The field strengths F μ ν I of A μ I and R μ ν I of ψ μ I satisfy the self-duality conditions F μ ν I = + (1 / 2) ϵ μ ν ρ σ F ρ σ I and R μ ν I = + (1 / 2) ϵ μ ν ρ σ R ρ σ I. The lowest flow of super-KdV equations and super-KP equations are embedded into this system in ways more natural than the conventional supersymmetric self-dual theories in D = 2 + 2. This indicates that our theory even without supersymmetry in D = 2 + 2 can serve as the "Master Theory" of all supersymmetric integrable systems in lower dimensions. Our D = 2 + 2 result is further generalized to D = n + n (n = 3 , 4 , ⋯) with the field content (A μ I , ψ μ I , χ I , B μ 1 ⋯ μ n − 3 ) , with the (n − 3) -rank auxiliary Abelian tensor B μ 1 ⋯ μ n − 3 . The generalized self-dual conditions are ▪ and ▪. We conjecture that our theory in D = n + n is the "Grand-Master Theory" of all supersymmetric integrable systems in lower dimensions. [ABSTRACT FROM AUTHOR]

In this work, we study the rotating wormhole geometries supported by a three-form field. We demonstrate for particular choices of parameters that it is possible for the matter fields threading the wormhole to satisfy the null and weak energy conditions throughout the spacetime, when the three-form field is present. In this case, the form field is interpreted as supporting the wormhole and the energy condition violation is restricted only to the 3-form fields. Thus, the three-form curvature terms, which may be interpreted as a gravitational fluid, sustain these wormhole geometries. Additionally, we also address the ergoregion of the solutions. [ABSTRACT FROM AUTHOR]

Motivated by the principles of the conformal bootstrap, primarily the principle of Locality, simultaneously with the requirement of space-time supersymmetry, we reconsider constructions of compactified superstring models. Starting from requirements of space-time supersymmetry and mutual locality, we construct a complete set of physical fields of orbifolds of Gepner models. To technically implement this, we use spectral flow generators to construct all physical fields from the chiral primary fields. The set of these spectral flow operators forms a so-called admissible group G a d m , which defines a given orbifold. The action of these operators produces a collection of physical fields consistent with the action of supersymmetry generators. The selection of mutually local fields from this collection is carried out using the mirror group G a d m ⁎. The permutation of G a d m and G a d m ⁎ replaces the original orbifold with a mirror one that satisfies the same conditions as the original one. This also implies that the resulting model is modular invariant. [ABSTRACT FROM AUTHOR]

In this paper, we address the nature of spacetime in quantum gravity in light of a new version of the holographic principle that has established a relationship between string theory and polymer holonomy structures similar to Loop Quantum Cosmology spin networks. In front of the results found out, it is possible to argue that, for such a relationship to work, spacetime must be seen as emergent from a fundamental structure whose degrees of freedom correspond to quantum correlations only. [ABSTRACT FROM AUTHOR]

We show that the sigma models with target spaces supersymmetric heterotic backgrounds with S U (2) and S U (3) holonomy are invariant under a W-symmetry algebra generated by the covariantly constant forms of these backgrounds. The closure of the W-algebra requires additional generators that we identify. We prove that the chiral anomalies of all these symmetries are consistent at one-loop in perturbation theory. We also demonstrate that these anomalies cancel at the same loop level either by adding suitable finite local counterterms in the sigma model effective action or by assuming a plausible quantum correction to the transformations. Such a correction is compatible with both the cancellation mechanism for spacetime frame rotation and gauge transformation anomalies, and the correction to the heterotic supergravity up to two loops in the sigma model perturbation theory. [ABSTRACT FROM AUTHOR]

We continue our exploration of the holographic duality between string theory in backgrounds that interpolate between asymptotically linear dilaton spacetime in the UV and A d S 3 in the IR, and the corresponding boundary theories. In previous papers, [1,2] , we showed that states in the bulk theory that are described by non-trivial asymptotically linear dilaton geometries, such as black holes and deformed global A d S 3 , can be described in the boundary theory by a single-trace T T ¯ deformation of a symmetric product theory. In those papers, we restricted to states with vanishing (angular) momentum; in this paper, we extend the analysis to states with arbitrary momentum, and show that the picture presented in the earlier papers generalizes to this case. [ABSTRACT FROM AUTHOR]

In the extended phase space, Born-Infeld anti-de Sitter black holes exhibit diverse phase transitions including the van der Waals type and reentrant phase transitions. In this paper, we aim to investigate the potential thermodynamical features for Born-Infeld black holes when the cosmological constant vanishes. Quite differently, although there present the swallow tail behavior of the free energy and temperature-entropy criticality, no phase transition will occur when we consider the thermodynamical stability. Further, based on these findings, the phase structures are explicitly shown with the stable, unstable black hole, and non-black hole regions. After excluding the non-black hole region, we observe that the scalar curvature of the Ruppeiner geometry is always positive, indicating a dominant repulsive interaction for both the stable and unstable black holes. Particularly, we also establish the topology for the thermodynamical critical point. By calculating the topological number, we confirm that this critical point of the Born-Infeld black holes is a conventional one. Although it is not an indicator of the first small-large black hole phase transition, it does signify the emergence of stable intermediate black holes. All these results uncover the thermodynamical features of the Born-Infeld black holes in the absence of the cosmological constant. [ABSTRACT FROM AUTHOR]

We demonstrate the existence of the first-class constraints on the massless Abelian 3-form theory which generate the classical gauge symmetry transformations for this theory in any arbitrary D-dimension of spacetime. We write down the explicit expression for the generator in terms of these first-class constraints. Using the celebrated Noether theorem, corresponding to the gauge symmetry transformations, we derive the Noether conserved current and conserved charge. The latter is connected with the first-class constraints of the theory in a subtle manner as we demonstrate clearly in our present investigation. We comment on the first-class constraints within the framework of Becchi-Rouet-Stora-Tyutin (BRST) formalism where the conserved (anti-)BRST charges are the generalizations of the above generator for the classical gauge symmetry transformation. The standard Noether conserved (anti-)BRST charges are found to be non-nilpotent. We derive the nilpotent versions of the (anti-)BRST charges. One of the interesting observations of our present endeavor is the result that only the nilpotent versions of the conserved (anti-)BRST charges lead to the annihilation of the physical states by the operator form of the first-class constraints at the quantum level which is consistent with the Dirac quantization condition for the systems that are endowed with any kind of constraints. We comment on the existence of the Curci-Ferrari (CF) type restrictions from different theoretical angles, too. • Local gauge symmetry of the D-dimensional massless Abelian 3-form theory is elevated to (anti-)BRST symmetries. • Noether (anti-)BRST charges are found to be non-nilpotent. • Nilpotent versions of the (anti-)BRST charges are derived. • Physicality criteria w.r.t. (anti-)BRST charges lead to the annihilation of the physical states by the first-class constraints. [ABSTRACT FROM AUTHOR]

A fine tuned rainbow gravity describes both relativistic quantum particles and anti-particles alike. That is, the ratio y = E / E P in the rainbow functions g 0 (y) and g 1 (y) should be fine tuned into 0 ≤ y = E / E P ≤ 1 ⇒ y = | E | / E P , otherwise rainbow gravity will only secure Planck's energy scale E p as the maximal energy for relativistic particles and the anti-particles are left unfortunate (in the sense that their energies will be indefinitely unbounded). Using this fine tuning we discuss the rainbow gravity effect on Klein-Gordon (KG) oscillators in Som-Raychaudhuri cosmic string rainbow gravity spacetime background. We use the rainbow functions: (i) g 0 (y) = 1 , g 1 (y) = 1 − ϵ y n , n = 1 , 2 , loop quantum gravity motivated pairs, (ii) g 0 (y) = g 1 (y) = (1 − ϵ y) − 1 , a horizon problem motivated pair, and (iii) g 0 (y) = (e ϵ y − 1) / ϵ y , g 1 (y) = 1 , a gamma-ray bursts motivated pair. We show that the energies obtained using the first two rainbow functions in (i) completely comply with the rainbow gravity model and secure Planck's energy E p as the maximal energy for both particles and anti-particles. The rainbow function pair in (ii) has no effect on massless KG-oscillators. Whereas, the one in (iii) does not show any eminent tendency towards the Planck's energy as the maximal energy. [ABSTRACT FROM AUTHOR]

Abstract It is proved that dynamically formed Reissner-Nordström-de Sitter (RNdS) black holes, which have recently been claimed to provide counter-examples to the Penrose strong cosmic censorship conjecture, are characterized by unstable (singular) inner Cauchy horizons. The proof is based on analytical techniques which explicitly reveal the fact that charged massive scalar fields in the charged RNdS black-hole spacetime are characterized, in the large-coupling regime, by quasinormal resonant frequencies with ℑ ω min < 1 2 κ + , where κ + is the surface gravity of the black-hole event horizon. This result implies that the corresponding relaxation rate ψ ∼ e − ℑ ω min t of the collapsed charged fields is slow enough to guarantee, through the mass-inflation mechanism, the instability of the dynamically formed inner Cauchy horizons. Our results reveal the physically important fact that, taking into account the unavoidable presence of charged matter fields in dynamically formed charged spacetimes, non-asymptotically flat RNdS black holes are globally hyperbolic and therefore respect the fundamental strong cosmic censorship conjecture. [ABSTRACT FROM AUTHOR]

Abstract The theory of fractional calculus is attracting a lot of attention from mathematicians as well as physicists. The fractional generalisation of the well-known ordinary calculus is being used extensively in many fields, particularly in understanding stochastic process and fractal dynamics. In this paper, we apply the techniques of fractional calculus to study some specific modifications of the geometry of submanifolds. Our generalisation is applied to extend the Israel formalism which is used to glue together two spacetimes across a timelike, spacelike or a null hypersurface. In this context, we show that the fractional extrapolation leads to some striking new results. More precisely we demonstrate that, in contrast to the original Israel formalism, where many spacetimes can only be joined together through an intermediate thin hypersurface admitting effective matter fields violating standard energy conditions, the fractional generalisation allows these spacetimes to be smoothly sewed together without any such requirements on the stress tensor of the matter fields. We discuss the ramifications of these results for spacetime structure and the possible implications for gravitational physics. [ABSTRACT FROM AUTHOR]

Abstract We introduce gauge theories based on a class of disconnected gauge groups, called principal extensions. Although in this work we focus on 4d theories with N = 2 SUSY, such construction is independent of spacetime dimensions and supersymmetry. These groups implement in a consistent way the discrete gauging of charge conjugation, for arbitrary rank. Focusing on the principal extension of SU (N) , we explain how many of the exact methods for theories with 8 supercharges can be put into practice in that context. We then explore the physical consequences of having a disconnected gauge group: we find that the Coulomb branch is generically non-freely generated, and the global symmetry of the Higgs branch is modified in a non-trivial way. [ABSTRACT FROM AUTHOR]

Abstract We present an approach to analyze the scalar integrals of any Feynman diagrams in detail here. This method not only completely recovers some well-known results in the literature, but also produces some new results on the C 0 function. The approach can be employed to evaluate the coefficient of arbitrary power of ε in the expansion of a scalar integral, where D = 4 − 2 ε denotes the time–space dimension. [ABSTRACT FROM AUTHOR]

Abstract We continue our study of string theory in a background that interpolates between A d S 3 in the infrared and a linear dilaton spacetime IR 1 , 1 × IR ϕ in the UV. This background corresponds via holography to a C F T 2 deformed by an operator of dimension (2 , 2). We discuss the structure of spatial entanglement in this model, and compare it to the closely related T T ‾ deformed C F T 2. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we present the results of our investigation relating particle dynamics and non-commutativity of space–time by using Dirac's constraint analysis. In this study, we re-parameterise the time t = t (τ) along with x = x (τ) and treat both as configuration space variables. Here, τ is a monotonic increasing parameter and the system evolves with this parameter. After constraint analysis, we find the deformed Dirac brackets similar to the κ -deformed space–time and also, get the deformed Hamilton's equations of motion. Moreover, we study the effect of non-commutativity on the generators of Galilean group and Poincare group and find undeformed form of the algebra. Also, we work on the extended space analysis in the Lagrangian formalism. We find the primary as well as the secondary constraints. Strikingly on calculating the Dirac brackets among the phase space variables, we obtain the classical version of κ -Minkowski algebra. [ABSTRACT FROM AUTHOR]

The slow rotation of Kerr-NUT spacetime is explored by taking into account the linear form of rotation and NUT parameters in the dynamical Chern-Simon gravity theory, which can be formulated from a scalar field describing the background. We show that in the absence of the potential scalar field, the metric potential does not respect the effect of the NUT parameter, although the scalar field is affected by the rotation and NUT parameters. As a result, unlike the slowly rotating black hole solution presented in [1] , the cross term of the metric potential, which has both rotation and NUT parameters, has no contribution up to the leading order of the first order perturbation. [ABSTRACT FROM AUTHOR]

In this work we study the deformations into Lie bialgebras of the three relativistic Lie algebras: de Sitter, Anti-de Sitter and Poincaré, which describe the symmetries of the three maximally symmetric spacetimes. These algebras represent the centerpiece of the kinematics of special relativity (and its analogue in (Anti-)de Sitter spacetime), and provide the simplest framework to build physical models in which inertial observers are equivalent. Such a property can be expected to be preserved by Quantum Gravity, a theory which should build a length/energy scale into the microscopic structure of spacetime. Quantum groups, and their infinitesimal version ‘Lie bialgebras’, allow to encode such a scale into a noncommutativity of the algebra of functions over the group (and over spacetime, when the group acts on a homogeneous space). In 2+1 dimensions we have evidence that the vacuum state of Quantum Gravity is one such ‘noncommutative spacetime’ whose symmetries are described by a Lie bialgebra. It is then of great interest to study the possible Lie bialgebra deformations of the relativistic Lie algebras. In this paper, we develop a characterization of such deformations in 2, 3 and 4 spacetime dimensions motivated by physical requirements based on dimensional analysis, on various degrees of ‘manifest isotropy’ (which implies that certain symmetries, i.e. Lorentz transformations or rotations, are ‘more classical’), and on discrete symmetries like P and T. On top of a series of new results in 3 and 4 dimensions, we find a no-go theorem for the Lie bialgebras in 4 dimensions, which singles out the well-known ‘ κ -deformation’ as the only one that depends on the first power of the Planck length, or, alternatively, that possesses ‘manifest’ spatial isotropy. [ABSTRACT FROM AUTHOR]

In this paper, we have analytically computed the conductivity of holographic superconductors in the framework of Born–Infeld electrodynamics taking into account the backreaction of the matter fields on the bulk spacetime metric. The effect of the Born–Infeld electrodynamics is incorporated in the metric. The band gap energy is found to be corrected by the backreaction and Born–Infeld parameters. The conductivity expression is then compared with that obtained from a self-consistent approach. [ABSTRACT FROM AUTHOR]

The black-hole information puzzle, first discussed by Hawking four decades ago, has attracted much attention over the years from both physicists and mathematicians. One of the most intriguing suggestions to resolve the information paradox is due to Bekenstein, who has stressed the fact that the low-energy part of the semi-classical black-hole emission spectrum is partly blocked by the curvature potential that surrounds the black hole. As explicitly shown by Bekenstein, this fact implies that the gray-body emission spectrum of a ( 3 + 1 )-dimensional black hole is considerably less entropic than the corresponding radiation spectrum of a perfectly thermal black-body emitter. Using standard ideas from quantum information theory, it was shown by Bekenstein that, in principle, the filtered Hawking radiation emitted by a ( 3 + 1 )-dimensional Schwarzschild black hole may carry with it a substantial amount of information, the information which was suspected to be lost. It is of physical interest to test the general validity of the “information leak” scenario suggested by Bekenstein as a possible resolution to the Hawking information puzzle. To this end, in the present paper we analyze the semi-classical entropy emission properties of higher -dimensional black holes. In particular, we provide evidence that the characteristic Hawking quanta of ( D + 1 ) -dimensional Schwarzschild black holes in the large D ≫ 1 regime are almost unaffected by the spacetime curvature outside the black-hole horizon. This fact implies that, in the large- D regime, the Hawking black-hole radiation spectra are almost purely thermal, thus suggesting that the emitted quanta cannot carry the amount of (non-thermal) information which is required in order to resolve the information paradox. Our analysis therefore suggests that the elegant information leak scenario suggested by Bekenstein, which is based on the effective gray-body (rather than a black-body) nature of the black-hole emission spectra, cannot provide a generic resolution to the intriguing Hawking information paradox. [ABSTRACT FROM AUTHOR]

The ten-dimensional supergravity theory is a geometric low-energy effective theory and the equations of motion for its fields can be obtained from string theory by computing β functions. With d compact dimensions, an O ( d , d ; Z ) geometric structure can be added to it giving the supergravity theory with T-duality manifest. In this paper, this is constructed through the use of a suitable star product whose role is the one to implement the weak constraint on the fields and the gauge parameters in order to have a closed gauge symmetry algebra. The consistency of the action here proposed is based on the orthogonality of the momenta associated with fields in their triple star products in the cubic terms defined for d ≥ 1 . This orthogonality holds also for an arbitrary number of star products of fields for d = 1 . Finally, we extend our analysis to the double sigma model, non-commutative geometry and open string theory. [ABSTRACT FROM AUTHOR]

We explain a procedure to manifest the Bern–Carrasco–Johansson duality between color and kinematics in n -point one-loop amplitudes of a variety of supersymmetric gauge theories. Explicit amplitude representations are constructed through a systematic reorganization of the integrands in the Cachazo–He–Yuan formalism. Our construction holds for any nonzero number of supersymmetries and does not depend on the number of spacetime dimensions. The cancellations from supersymmetry multiplets in the loop as well as the resulting power counting of loop momenta is manifested along the lines of the corresponding superstring computations. The setup is used to derive the one-loop version of the Kawai–Lewellen–Tye formula for the loop integrands of gravitational amplitudes. [ABSTRACT FROM AUTHOR]

We explore the analytical structure of the generalized λ -deformation of AdS p × S p spaces and construct new integrable backgrounds which depend on ( p + 1 ) continuous parameters. [ABSTRACT FROM AUTHOR]

Most existing cosmological entanglement studies are focused on the isotropic Robertson–Walker (RW) spacetime. Here we go beyond this limitation and study the influence of anisotropy on entanglement generated by dynamical spacetime. Since the isotropic spacetime is viewed as a background medium and the anisotropy is incorporated as perturbation, we decompose entanglement entropy into isotropic and anisotropic contributions. The latter is shown to be non-negligible by analyzing two cosmological models with weak and conformal coupling. We also show the possibility of using entanglement to infer about universe features. [ABSTRACT FROM AUTHOR]

We investigate the dynamics of entanglement between two atoms in de Sitter spacetime and in thermal Minkowski spacetime. We treat the two-atom system as an open quantum system which is coupled to a conformally coupled massless scalar field in the de Sitter invariant vacuum or to a thermal bath in the Minkowski spacetime, and derive the master equation that governs its evolution. We compare the phenomena of entanglement creation, degradation, revival and enhancement for the de Sitter spacetime case with that for the thermal Minkowski spacetime case. We find that the entanglement dynamics of two atoms for these two spacetime cases behave quite differently. In particular, the two atoms interacting with the field in the thermal Minkowski spacetime (with the field in the de Sitter-invariant vacuum), under certain conditions, could be entangled, while they would not become entangled in the corresponding de Sitter case (in the corresponding thermal Minkowski case). Thus, although a single static atom in the de Sitter-invariant vacuum responds as if it were bathed in thermal radiation in a Minkowski universe, with the help of the different dynamic evolution behaviors of entanglement for two atoms one can in principle distinguish these two universes. [ABSTRACT FROM AUTHOR]

The absence, so far, of any graviton signatures at the LHC imposes severe constraints on the Randall–Sundrum scenario. Although a generalization to higher dimensions with nested warpings has been shown to avoid these constraints, apart from incorporating several other phenomenologically interesting features, moduli stabilization in such models has been an open question. We demonstrate here how both the moduli involved can be stabilized, employing slightly different mechanisms for the two branches of the theory. This also offers a dynamical mechanism to generate and stabilise the scale for the Universal Extra Dimensions, another long-standing issue. [ABSTRACT FROM AUTHOR]

We show that the uncertainty in distance and time measurements found by the heuristic combination of quantum mechanics and general relativity is reproduced in a purely classical and flat multi-fractal spacetime whose geometry changes with the probed scale (dimensional flow) and has non-zero imaginary dimension, corresponding to a discrete scale invariance at short distances. Thus, dimensional flow can manifest itself as an intrinsic measurement uncertainty and, conversely, measurement-uncertainty estimates are generally valid because they rely on this universal property of quantum geometries. These general results affect multi-fractional theories, a recent proposal related to quantum gravity, in two ways: they can fix two parameters previously left free (in particular, the value of the spacetime dimension at short scales) and point towards a reinterpretation of the ultraviolet structure of geometry as a stochastic foam or fuzziness. This is also confirmed by a correspondence we establish between Nottale scale relativity and the stochastic geometry of multi-fractional models. [ABSTRACT FROM AUTHOR]

In non-relativistic quantum mechanics, the Heisenberg Uncertainty Principle states a fundamental limit to the accuracy in the measurement of pairs of conjugate variables, such as position and momentum. Based on a semiclassical geometric approach, it has been recently proposed a generalization of the uncertainty principle under the relativistic case, which could be extended to General Relativity. This formalism was applied to the Schwarzschild and de Sitter spacetime, showing that the uncertainty relations obtained can be mapped into deformations of Generalized Heisenberg principles well-known in the literature and obtained from the different models of quantum gravity proposed. In the present study, the generalized Heisenberg Principle is derived from the commutator relation, and has been applied to the classical gravitational tests and the derived consequences are framed and analyzed. [ABSTRACT FROM AUTHOR]

We study W 3 toroidal conformal blocks for degenerate primary fields in AdS/CFT context. In the large central charge limit W 3 algebra reduces to sl 3 algebra and sl 3 blocks are defined as contributions to W 3 blocks coming from the generators of sl 3 subalgebra. We consider the construction of sl 3 toroidal blocks in terms of Wilson lines operators of 3 d Chern-Simons gravity in the thermal AdS 3 space-time. According to the correspondence, degenerate primary fields are associated with Wilson lines operators acting in the corresponding finite-dimensional sl 3 representations. We verify this dual construction for one-point toroidal block using sl 3 tensor technique in the bulk theory and an algorithm based on AGT correspondence in the boundary CFT. [ABSTRACT FROM AUTHOR]

Light radions constitute one of the few surviving possibilities for observable new particle states at the sub-TeV level which arise in models with extra spacetime dimensions. It is already known that the 125 GeV state discovered at CERN is unlikely to be a pure radion state, since its decays resemble those of the Standard Model Higgs boson too closely. However, due to experimental errors in the measured decay widths, the possibility still remains that it could be a mixture of the radion with one (or more) Higgs states. We use the existing LHC data at 8 and 13 TeV to make a thorough investigation of this possibility. Not surprisingly, it turns out that this model is already constrained quite effectively by direct LHC searches for an additional scalar heavier than 125 GeV. We then make a detailed study of the so-called ‘conformal point’, where this heavy state practically decouples from (most of) the Standard Model fields. Some projections for the future are also included. [ABSTRACT FROM AUTHOR]

The conformal gravity remarkably boosts our prehension of gravity theories. We find a series of dynamical solutions in the W 2 -conformal gravity, including generalized Schwarzschild–Friedmann–Robertson–Walker (GSFRW), charged generalized Schwarzschild–Friedmann–Robertson–Walker (CGSFRW), especially rotating Friedmann–Robertson–Walker (RFRW), charged rotating Friedmann–Robertson–Walker (CRFRW), and a dynamical cylindrically symmetric solutions. The RFRW, CRFRW and the dynamical cylindrically symmetric solutions are never found in the Einstein gravity and modified gravities. The GSFRW and CGSFRW solutions take different forms from the corresponding solutions in the Einstein gravity. [ABSTRACT FROM AUTHOR]

This paper is mainly concerned with the construction of new off-shell higher spin N = 1 supermultiplets in three spacetime dimensions. We elaborate on the gauge prepotentials and linearised super-Cotton tensors for higher spin N = 1 superconformal geometry and propose compensating superfields required to formulate off-shell massless higher spin supermultiplets. The corresponding gauge-invariant actions are worked out explicitly using an auxiliary oscillator realisation. We construct, for the first time, off-shell massive higher spin supermultiplets. The gauge-invariant actions for these supermultiplets are obtained by adding Chern–Simons like mass terms (that is, higher spin extensions of the linearised action for N = 1 conformal supergravity) to the actions for the massless supermultiplets. For each of the massive gravitino and supergravity multiplets, we propose two dually equivalent formulations. [ABSTRACT FROM AUTHOR]

For every prime number p it is possible to define a p -adic version of the Veneziano amplitude and its higher-point generalizations. Multiplying together the real amplitude with all its p -adic counterparts yields the adelic amplitude. At four points it has been argued that the adelic amplitude, after regulating the product that defines it, equals one. For the adelic 5-point amplitude, there exist kinematic regimes where no regularization is needed. This paper demonstrates that in special cases within this regime, the adelic product can be explicitly evaluated in terms of ratios of the Riemann zeta function, and observes that the 5-point adelic amplitude is not given by a single analytic function. Motivated by this fact to study new regularization procedures for the 4-point amplitude, an alternative formalism is presented, resulting in non-constant amplitudes that are piecewise analytic in the three scattering channels, including one non-constant adelic amplitude previously suggested in the literature. Decomposing the residues of these amplitudes into weighted sums of Gegenbauer polynomials, numerical evidence indicates that in special ranges of spacetime dimensions all the coefficients are positive, as required by unitarity. [ABSTRACT FROM AUTHOR]

In this paper we develop the frame-like gauge invariant formulation for the massive two-column bosonic fields in (anti) de Sitter space-times. We begin with the partially massless cases in AdS and dS and then we combine these results into the general massive theory. Separate section is devoted to the special case where both columns have equal number of indices. [ABSTRACT FROM AUTHOR]

In applying the gauge–gravity duality to the quark–gluon plasma, one models the plasma using a particular kind of field theory with specified values of the temperature, magnetic field, and so forth. One then assumes that the bulk, an asymptotically AdS black hole spacetime with properties chosen to match those of the boundary field theory, can be embedded in string theory. But this is not always the case: there are field theories with no bulk dual. The question is whether these theories might include those used to study the actual plasmas produced at such facilities as the RHIC experiment or the relevant experiments at the LHC. We argue that, provided that due care is taken to include the effects of the angular momentum associated with the magnetic fields experienced by the plasmas produced by peripheral collisions, the existence of the dual can be established for the RHIC plasmas. In the case of the LHC plasmas, the situation is much more doubtful. [ABSTRACT FROM AUTHOR]

We analyze the critical behavior of isotropic systems with dipole-dipole interaction by renormalization-group methods in fixed space-time dimensions. Working in three-dimensional theory we analytically find three-loop expressions for critical exponents in the limit of dominating dipole-dipole forces. Resummation of the series obtained provides numerical values close to O (3) -theory predictions, justifying the applicability of such a simplified model to systems with strong dipole-dipole interaction. [ABSTRACT FROM AUTHOR]

The thermodynamics for a quantum corrected Schwarzschild black hole with AdS background is investigated. First, the black hole metric is introduced and given when the spherical symmetric quantum fluctuations of spacetime are considered for Schwarzschild AdS black hole. Then, based on AdS background, we get the free energy for the quantum corrected black hole by AdS gravity renormalization and saddle-point approximation. By the spherical symmetric quantum fluctuation in AdS spacetime is considered, there are three main results found. Firstly, due to quantum fluctuation, there is a divergence term in the Euclidean action, which contributes to the energy of spacetime. Secondly, the entropy of the modified black hole is still proportional to the horizon area. But when the contribution of quantum fluctuations is deducted, the relationship between entropy and area is not so. It shows that, the area entropy theorem for the black hole is the both effect of quantum fluctuations and black hole. Thirdly, quantum fluctuation doesn't affect the temperature of Hawking-Page transition, but the radius of the black hole of Hawking-Page transition will be corrected. • A quantum corrected Schwarzschild black hole in AdS spacetime is introduced. • Due to quantum fluctuation, there is a divergence term in the Euclidean action which contributes to the energy of spacetime. • We got the reduced free energy and thermodynamic quantity when the contribution of quantum fluctuations is deducted. • Based on quantum fluctuation, we find that the area entropy theorem is both effect of quantum fluctuations and black hole. [ABSTRACT FROM AUTHOR]

In general, a finite metric function at the center of a black hole describes a non-singular spacetime but an infinite metric at the center gives a singular spacetime, where the former is associated with convergent Ricci and Kretschmann scalars together with complete radial geodesics, while the latter is related to divergent Ricci and Kretschmann scalars together with incomplete radial geodesics. For the charged black hole in the four-dimensional Einstein-Gauss-Bonnet theory, we find that its metric function is finite at its center in one region of parameters but complex in the other region of parameters. The finite case describes a strange spacetime which presents the Ricci and Kretschmann scalars of a singular spacetime and the radial geodesics of a non-singular spacetime, while the complex case gives rise to the similar situation. We verify that the cosmic censorship conjecture is maintained for the black hole model. Further, we investigate the second-order phase transition, quasinormal modes of perturbation of a test scalar field in the eikonal limit, and shadow radius for the black hole and find that the thermodynamic and dynamic properties depend on the metrics. In this way, we connect the internal structure with the thermodynamics and dynamics for this black hole. Moreover, we compare such a black hole of modified gravity with the Reissner-Nordström black hole of Einstein's general relativity in these thermodynamic and dynamic properties. [ABSTRACT FROM AUTHOR]

We apply a generalized field ansatz to describe the spherically symmetric sector of classical solutions in the electroweak theory. This sector contains Abelian magnetic monopoles labeled by their magnetic charge n = ± 1 , ± 2 , ... , the non-Abelian monopole for n = ± 2 found previously by Cho and Maison (CM), and also the electric oscillating solutions. All magnetic monopoles have infinite energy. We analyze their perturbative stability and use the method of complex spacetime tetrad to separate variables and reduce the perturbation equations to multi-channel Schroedinger-type eigenvalue problems. The spectra of perturbations around the CM monopole do not contain negative modes, hence this solution is stable. The n = ± 1 Abelian monopole is also stable, but all monopoles with | n | ≥ 2 are unstable with respect to perturbations with angular momentum j = | n | / 2 − 1. The Abelian | n | = 2 monopole is unstable only within the j = 0 sector whereas the CM monopole also has | n | = 2 and belongs to the same sector, hence it may be viewed as a stable remnant of the decay of the Abelian monopole. One may similarly conjecture that stable remnants exist also for monopoles with | n | > 2 , hence the CM monopole is just the first member of a sequence of non-Abelian monopoles with higher magnetic charges. Only the CM monopole is spherically symmetric while all non-Abelian monopoles with | n | > 2 are not rotationally invariant. [ABSTRACT FROM AUTHOR]

The photon ring, shadow and observational appearance of the emission originating near a charged black-bounce are investigated. Based on the geodesic analysis, we determine the upper and lower limits of critical impact parameters of a charged black-bounce. In particular, we find that the charged black-bounce shares the same critical impact parameter with the Reissner-Nordström black hole. In addition, we classify the light trajectories coming from the region near the charged black-bounce by utilizing the rays tracing procedure, and then investigate the observational appearance of the emissions from a thin disk accretion and a spherically symmetric infalling accretion. We reveal that a large charge increases the observed intensity but decreases the apparent size of shadows, and that the photon ring presents the intrinsic property of a spacetime geometry, which is independent of the types of the two accretions. Our results are in good agreement with the recent observations. [ABSTRACT FROM AUTHOR]

We study analytically the role of initial conditions in nonequilibrium quantum dynamics considering the one-dimensional ferromagnets in the regime of spontaneously broken symmetry. We analyze the expectation value of local operators for the infinite-dimensional space of initial conditions of domain wall type, generally intended as initial conditions spatially interpolating between two different ground states. At large times the unitary time evolution takes place inside a light cone produced by the spatial inhomogeneity of the initial condition. In the innermost part of the light cone the form of the space-time dependence is universal, in the sense that it is specified by data of the equilibrium universality class. The global limit shape in the variable x / t changes with the initial condition. In systems with more than two ground states the tuning of an interaction parameter can induce a transition which is the nonequilibrium quantum analog of the interfacial wetting transition occurring in classical systems at equilibrium. We illustrate the general results through the examples of the Ising, Potts and Ashkin-Teller chains. [ABSTRACT FROM AUTHOR]

We present a number of explicit calculations of Renyi and entanglement entropies in situations where the entangling surface intersects the boundary of d -dimensional Minkowski spacetime. When the boundary is a single plane we compute the contribution to the entropy due to this intersection, first in the case of the Neumann and Dirichlet boundary conditions, and then in the case of a generic Robin type boundary condition. The flow in the boundary coupling between the Neumann and Dirichlet phases is analyzed in arbitrary dimension d and is shown to be monotonic, the peculiarity of d = 3 case is noted. We argue that the translational symmetry along the entangling surface is broken due the presence of the boundary which reveals that the entanglement is not homogeneous. In order to characterize this quantitatively, we introduce a density of entanglement entropy and compute it explicitly. This quantity clearly indicates that the entanglement is maximal near the boundary. We then consider the situation where the boundary is composed of two parallel planes at a finite separation and compute the entanglement entropy as well as its density in this case. The complete contribution to entanglement entropy due to the boundaries is shown not to depend on the distance between the planes and is simply twice the entropy in the case of single plane boundary. Additionally, we find how the area law, the part in the entropy proportional to the area of entire entangling surface, depends on the size of the separation between the two boundaries. The latter is shown to appear in the UV finite part of the entropy. [ABSTRACT FROM AUTHOR]