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this review summarizes the current status of the energy conditions in general relativity and quantum field theory. we provide a historical review and a summary of technical results and applications, complemented with a few new derivations and discussions. we pay special attention to the role of the equations of motion ...
energy conditions in general relativity and quantum field theory
in this paper we derive for the first time the n3lo gravitational spin-orbit coupling at order g4 in the post-newtonian (pn) approximation within the effective field theory (eft) of gravitating spinning objects. this represents the first computation in a spinning sector involving three-loop integration. we provide a co...
n3lo gravitational spin-orbit coupling at order g4
teleparallel gravity and its popular generalization gravity can be formulated as fully invariant (under both coordinate transformations and local lorentz transformations) theories of gravity. several misconceptions about teleparallel gravity and its generalizations can be found in the literature, especially regarding t...
teleparallel theories of gravity: illuminating a fully invariant approach
we derive the conservative dynamics of nonspinning binaries to third post-minkowskian order, using the effective field theory (eft) approach introduced in [g. kälin and r. a. porto, j. high energy phys. 11 (2020) 106, 10.1007/jhep11(2020)106] together with the boundary-to-bound dictionary developed in [g. kälin and r. ...
conservative dynamics of binary systems to third post-minkowskian order from the effective field theory approach
we use the subleading soft-graviton theorem to construct an operator tz z whose insertion in the four-dimensional tree-level quantum gravity s matrix obeys the virasoro-ward identities of the energy momentum tensor of a two-dimensional conformal field theory (cft2 ). the celestial sphere at minkowskian null infinity pl...
2d stress tensor for 4d gravity
we complete the calculation of conservative two-body scattering dynamics at fourth post-minkowskian order, i.e., o (g4) and all orders in velocity, including radiative contributions corresponding to the tail effect in general relativity. as in previous calculations, we harness powerful tools from the modern scattering ...
scattering amplitudes, the tail effect, and conservative binary dynamics at o (g4)
unitary, lorentz-invariant quantum field theories in flat spacetime obey mi-crocausality: commutators vanish at spacelike separation. for interacting theories in more than two dimensions, we show that this implies that the averaged null energy, ∫ dutuu , must be non-negative. this non-local operator appears in the oper...
averaged null energy condition from causality
we compute the n3lo gravitational quadratic-in-spin interactions at g4 in the post-newtonian (pn) expansion via the effective field theory (eft) of gravitating spinning objects for the first time. this result contributes at the 5pn order for maximally-spinning compact objects, adding the spinning case to the static sec...
n3lo gravitational quadratic-in-spin interactions at g4
relativistic navier-stokes equations express the conservation of the energy-momentum tensor and the particle number current in terms of the local hydrodynamic variables: temperature, fluid velocity, and the chemical potential. we show that the viscous-fluid equations are stable and causal if one adopts suitable non-equ...
stable and causal relativistic navier-stokes equations
in the standard model, some combination of the baryon $\bf b$ and lepton $\bf l$ number symmetry is free of mixed anomalies with strong and electroweak $su(3) \times su(2) \times u(1)_{\tilde y}$ gauge forces. however, it can still suffer from a mixed gravitational anomaly, hypothetically pertinent to leptogenesis in t...
categorical symmetry of the standard model from gravitational anomaly
we study quantum effects in higher curvature extensions of general relativity using the functional renormalization group. new flow equations are derived for general classes of models involving ricci scalar, ricci tensor, and riemann tensor interactions. our method is applied to test the asymptotic safety conjecture for...
fixed points of quantum gravity and the dimensionality of the uv critical surface
we consider the twistor description of classical self-dual einstein gravity in the presence of a defect operator wrapping a certain ℂℙ1. the backreaction of this defect deforms the flat twistor space to that of eguchi-hanson space. we show that the celestial chiral algebra of self-dual gravity on the eguchi-hanson back...
the celestial chiral algebra of self-dual gravity on eguchi-hanson space
we study two-point functions of symmetric traceless local operators in the bulk of de sitter spacetime. we derive the källén-lehmann spectral decomposition for any spin and show that unitarity implies its spectral densities are nonnegative. in addition, we recover the källén-lehmann decomposition in minkowski space by ...
the källén-lehmann representation in de sitter spacetime
according to a number of arguments in quantum gravity, both model-dependent and model-independent, heisenberg's uncertainty principle is modified when approaching the planck scale. this deformation is attributed to the existence of a minimal length. the ensuing models have found entry into the literature under the term...
30 years in: quo vadis generalized uncertainty principle?
the double copy is a much-studied relationship between gauge theory and gravity amplitudes. recently, this was generalised to an infinite family of classical solutions to einstein's equations, namely stationary kerr-schild geometries. in this paper, we extend this to the taub-nut solution in gravity, which has a double...
the classical double copy for taub-nut spacetime
this topical review gives a comprehensive overview and assessment of recent results in causal dynamical triangulations, a modern formulation of lattice gravity, whose aim is to obtain a theory of quantum gravity nonperturbatively from a scaling limit of the lattice-regularized theory. in this manifestly diffeomorphism-...
quantum gravity from causal dynamical triangulations: a review
in this work, we revisit carrollian hydrodynamics, a type of non-lorentzian hydrodynamics which has recently gained increasing attentions due to its underlying connection with dynamics of spacetime near null boundaries, and we aim at exploring symmetries associated with conservation laws of carrollian fluids. with an e...
carrollian hydrodynamics from symmetries
we analyse the recent proposal of measuring a quantum gravity phenomenon in the lab by entangling two mesoscopic particles gravitationally. we give a generally covariant description of this phenomenon, where the relevant effect turns out to be a quantum superposition of proper times. we point out that if general relati...
on the possibility of laboratory evidence for quantum superposition of geometries
we perform a manifestly gauge-independent analysis of the vacuum stability in the standard model including two-loop matching, three-loop renormalization group evolution, and pure qcd corrections through four loops. all these ingredients are exact, except that light-fermion masses are neglected. we in turn apply the cri...
stability of the electroweak vacuum: gauge independence and advanced precision
new constraints are found that must necessarily hold for israel-stewart-like theories of fluid dynamics to be causal far away from equilibrium. conditions that are sufficient to ensure causality, local existence, and uniqueness of solutions in these theories are also presented. our results hold in the full nonlinear re...
nonlinear constraints on relativistic fluids far from equilibrium
background: r -process nucleosynthesis models rely, by necessity, on nuclear structure models for input. particularly important are β -decay half-lives of neutron-rich nuclei. at present only a single systematic calculation exists that provides values for all relevant nuclei making it difficult to test the sensitivity ...
large-scale evaluation of β -decay rates of r -process nuclei with the inclusion of first-forbidden transitions
we demonstrate the equivalence between observables in the kmoc and worldline formalisms for classical general relativity, highlighting the relation between the initial conditions in the two frameworks and how the keldysh-schwinger in-in formalism is contained in both of them even though the kmoc representation conventi...
the relation between kmoc and worldline formalisms for classical gravity
the current interest in laboratory detection of entanglement mediated by gravity was sparked by an information-theoretic argument: entanglement mediated by a local field certifies that the field is not classical. previous derivations of the effect modeled gravity as instantaneous; here we derive it from linearized quan...
locally mediated entanglement in linearized quantum gravity
a link between the semiclassical einstein equation and a maximal vacuum entanglement hypothesis is established. the hypothesis asserts that entanglement entropy in small geodesic balls is maximized at fixed volume in a locally maximally symmetric vacuum state of geometry and quantum fields. a qualitative argument sugge...
entanglement equilibrium and the einstein equation
recently, we introduced the "newman-penrose map", a novel correspondence between a certain class of solutions of einstein's equations and self-dual solutions of the vacuum maxwell equations, which we showed was closely related to the classical double copy. here, we give an alternative definition of this correspondence ...
twistor space origins of the newman-penrose map
no experiment to date has provided evidence for quantum features of the gravitational interaction. recently proposed tests suggest looking for the generation of quantum entanglement between massive objects as a possible route towards the observation of such features. motivated by advances in optical cooling of mirrors,...
observable quantum entanglement due to gravity
we propose a regularization procedure for the novel einstein-gauss-bonnet theory of gravity, which produces a set of field equations that can be written in closed form in four dimensions. our method consists of introducing a counterterm into the action, and does not rely on the embedding or compactification of any high...
derivation of regularized field equations for the einstein-gauss-bonnet theory in four dimensions
rastall gravity, originally developed in 1972, is currently undergoing a significant surge in popularity. rastall gravity purports to be a modified theory of gravity, with a non-conserved stress-energy tensor, and an unusual non-minimal coupling between matter and geometry, the rastall stress-energy satisfying
rastall gravity is equivalent to einstein gravity
recent times witnessed a significant interest in regularizing, a d →4 limit, of egb gravity initiated by glavan and lin [phys. rev. lett. 124, 081301 (2020)] by re-scaling gb coupling constant as α /(d -4 ) and taking limit d →4 , and in turn these regularized 4d gravities have nontrivial gravitational dynamics. intere...
wormholes in 4d einstein-gauss-bonnet gravity
schemes of gravitationally induced decoherence are being actively investigated as possible mechanisms for the quantum-to-classical transition. here, we introduce a decoherence process due to quantum gravity effects. we assume a foamy quantum spacetime with a fluctuating minimal length coinciding on average with the pla...
quantum gravitational decoherence from fluctuating minimal length and deformation parameter at the planck scale
euclidean wormholes—geometries which connect disconnected boundaries—present a challenge to a standard quantum mechanical interpretation of the theory. one potential resolution is that the gravitational path integral computes the ensemble average of many theories. the connected topologies contribute to the simplest pos...
free energy from replica wormholes
in this second paper of the series we continue to spell out a new program for quantum gravity, grounded in the notion of corner symmetry algebra and its representations. here we focus on tetrad gravity and its corner symplectic potential. we start by performing a detailed decomposition of the various geometrical quanti...
edge modes of gravity. part ii. corner metric and lorentz charges
we review both the kinematics and dynamics of non-lorentzian theories and their associated geometries. first, we introduce non-lorentzian kinematical spacetimes and their symmetry algebras. next, we construct actions describing the particle dynamics in some of these kinematical spaces using the method of nonlinear real...
a non-lorentzian primer
we perturbatively calculate classical radiation in yang-mills theory and dilaton gravity, to next-to-leading order in couplings. the radiation is sourced by the scattering of two relativistic massive scalar sources with the dynamical effect taken into account, corresponding to the post-minkowskian regime in gravity. we...
gravitational radiation from color-kinematics duality
this article aims to explain some of the basic facts about the questions raised in the title, without the technical details that are available in the literature. we provide a gentle introduction to some rather classical results about quantum field theory in curved spacetime and about the thermodynamic limit of quantum ...
why does quantum field theory in curved spacetime make sense? and what happens to the algebra of observables in the thermodynamic limit?
the classical double copy relates exact solutions of gauge, gravity, and other theories. although widely studied, its origins and domain of applicability have remained mysterious. in this letter, i show that a particular incarnation—the weyl double copy—can be derived using well-established ideas from twistor theory. a...
twistorial foundation for the classical double copy
using the gravitational decoupling by the minimal geometric deformation approach, we build an anisotropic version of the well-known tolman vii solution, determining an exact and physically acceptable interior two-fluid solution that can represent behavior of compact objects. comparison of the effective density and dens...
anisotropic tolman vii solution by gravitational decoupling
we consider two dimensional cft states that are produced by a gravitational path integral.as a first case, we consider a state produced by euclidean ads2 evolution followed by flat space evolution. we use the fine grained entropy formula to explore the nature of the state. we find that the naive hyperbolic space geomet...
bra-ket wormholes in gravitationally prepared states
in this note we show that models of natural inflation based on closed string axions are incompatible with the weak gravity conjecture (wgc). specifically, we use t- duality in order to map the bounds on the charge-to-mass ratio of particles imposed by the wgc, to constraints on the ratio between instanton actions and a...
fencing in the swampland: quantum gravity constraints on large field inflation
the observation of long-range rapidity correlations among particles in high-multiplicity p-p and p-pb collisions has created new opportunities for investigating novel high-density qcd phenomena in small colliding systems. we review experimental results related to the study of collective phenomena in small systems at rh...
novel collective phenomena in high-energy proton-proton and proton-nucleus collisions
hydrodynamics is a general theoretical framework for describing the long-time large-distance behaviors of various macroscopic physical systems, with its equations based on conservation laws such as energy-momentum conservation and charge conservation. recently there has been significant interest in understanding the im...
relativistic viscous hydrodynamics with angular momentum
we show that the upper bound of the classical qcd axion window can be significantly relaxed for low-scale inflation. if the gibbons-hawking temperature during inflation is lower than the qcd scale, the initial qcd axion misalignment angle follows the bunch-davies distribution. the distribution is peaked at the strong c...
qcd axion window and low-scale inflation
an early result of algebraic quantum field theory is that the algebra of any subregion in a qft is a von neumann factor of type iii$_1$, in which entropy cannot be well-defined because such algebras do not admit a trace or density states. however, associated to the algebra is a modular group of automorphisms characteri...
crossed product algebras and generalized entropy for subregions
we construct the on-shell amplitude basis and the corresponding effective operators for generic modified gravity theory, such as pure gravity with higher derivatives, scalar-tensor gravity, einstein-yang-mills, etc. taking the weyl tensor as the building block, we utilize the young tensor technique to obtain independen...
on-shell operator construction in the effective field theory of gravity
this paper points out the importance of the quantum nature of the gravitational interaction with matter in a linearized theory of quantum gravity induced entanglement of masses. we will show how the quantum interaction entangles the steady states of a closed system (eigenstates) of two test masses placed in the harmoni...
mechanism for the quantum natured gravitons to entangle masses
as a quantum gravity cut‑off, the species scale gets naturally compared to the energy scale of a scalar potential v in an eft. in this note, the species scale, its rate and their field dependence, to those of a scalar potential is compared. to that end, a string compactification leading to a scalar potential with the s...
bumping into the species scale with the scalar potential
ricci-flat solutions to einstein's equations in four dimensions are obtained as the flat limit of einstein spacetimes with negative cosmological constant. in the limiting process, the anti-de sitter energy-momentum tensor is expanded in laurent series in powers of the cosmological constant, endowing the system with the...
flat from anti de sitter
we introduce a covariant multipole expansion for the scattering of a massive particle emitting photons or gravitons in $d$ dimensions. we find that these amplitudes exhibit very powerful features such as universality, soft exponentiation, orbit and spin multipoles, etc. using ${\rm{so}}(d)$ representation theory we sho...
from scattering amplitudes to classical physics: universality, double copy and soft theorems
the m i c r o s c o p e mission was designed to test the weak equivalence principle (wep), stating the equality between the inertial and the gravitational masses, with a precision of 10-15 in terms of the eötvös ratio η . its experimental test consisted of comparing the accelerations undergone by two collocated test ma...
m i c r o s c o p e mission: final results of the test of the equivalence principle
the unification of quantum mechanics and general relativity has long been elusive. only recently have empirical predictions of various possible theories of quantum gravity been put to test. the dawn of multi-messenger high-energy astrophysics has been tremendously beneficial, as it allows us to study particles with muc...
white paper and roadmap for quantum gravity phenomenology in the multi-messenger era
we present a general procedure for constructing tensor networks that accurately reproduce holographic states in conformal field theories (cfts). given a state in a large-n cft with a static, semiclassical gravitational dual, we build a tensor network by an iterative series of approximations that eliminate redundant deg...
beyond toy models: distilling tensor networks in full ads/cft
the relativistic treatment of spin is a fundamental subject which has an old history. in various physical contexts it is necessary to separate the relativistic total angular momentum into an orbital and spin contribution. however, such decomposition is affected by ambiguities since one can always redefine the orbital a...
spin tensor and pseudo-gauges: from nuclear collisions to gravitational physics
following the recent theory of f(q) gravity, we continue to investigate the possible existence of wormhole geometries, where q is the non-metricity scalar. recently, the non-metricity scalar and the corresponding field equations have been studied for some spherically symmetric configurations in mustafa (phys lett b 821...
wormhole geometries in f(q) gravity and the energy conditions
we show that color-kinematics duality is a manifest property of the equations of motion governing currents and field strengths. for the nonlinear sigma model (nlsm), this insight enables an implementation of the double copy at the level of fields, as well as an explicit construction of the kinematic algebra and associa...
covariant color-kinematics duality
a comment on the letter by d. glavan and c. lin, einstein-gauss-bonnet gravity in 4-dimensional space-time, phys. rev. lett. 124, 081301 (2020)., 10.1103/physrevlett.124.081301 the authors of the letter offer a reply.
comment on "einstein-gauss-bonnet gravity in four-dimensional spacetime"
this review is dedicated to recent progress in the field of classical, interacting, massive spin-2 theories, with a focus on ghost-free bimetric theory. we will outline its history and its development as a nontrivial extension and generalisation of nonlinear massive gravity. we present a detailed discussion of the cons...
recent developments in bimetric theory
time has a fundamentally different character in quantum mechanics and in general relativity. in quantum theory events unfold in a fixed order while in general relativity temporal order is influenced by the distribution of matter. when matter requires a quantum description, temporal order is expected to become non-class...
bell's theorem for temporal order
in this contribution, we discuss the asymptotic safety scenario for quantum gravity with a functional renormalization group approach that disentangles dynamical metric fluctuations from the background metric. we review the state of the art in pure gravity and general gravity-matter systems. this includes the discussion...
quantum gravity: a fluctuating point of view
we construct a new yang-mills lagrangian based on a notion of minimal coupling that incorporates classical spin effects. the construction relies on the introduction of a new covariant derivative, which we name "classical spin covariant derivative", that is compatible with the three-point interaction of the $\sqrt{\math...
kerr binary dynamics from minimal coupling and double copy
we elaborate on the proposal of flat holography in which four-dimensional physics is encoded in two-dimensional celestial conformal field theory (ccft). the symmetry underlying ccft is the extended bms symmetry of (asymptotically) flat space­ time. we use soft and collinear theorems of einstein-yang-mills theory to der...
extended bms algebra of celestial cft
scrambling processes, which rapidly spread entanglement through many-body quantum systems, are difficult to investigate using standard techniques, but are relevant to quantum chaos and thermalization. in this letter, we ask if quantum machine learning (qml) could be used to investigate such processes. we prove a no-go ...
barren plateaus preclude learning scramblers
we compute the conservative dynamics of nonspinning binaries at fourth post-minkowskian order in the large-eccentricity limit, including both potential and radiation-reaction tail effects. this is achieved by obtaining the scattering angle in the worldline effective field theory approach and deriving the bound radial a...
conservative dynamics of binary systems at fourth post-minkowskian order in the large-eccentricity expansion
we discuss the presence of ghostly instabilities for metric-affine theories constructed with higher order curvature terms. we mainly focus on theories containing only the ricci tensor and show the crucial role played by the projective symmetry. the pathological modes arise from the absence of a pure kinetic term for th...
instabilities in metric-affine theories of gravity with higher order curvature terms
in this work, we propose the modeling of static wormholes within the f (r ,t ) extended theory of gravity perspective. we present some models of wormholes, which are constructed from different hypotheses for their matter content, i.e., different relations for their pressure components (radial and lateral) and different...
modeling wormholes in f (r ,t ) gravity
the success of relativistic hydrodynamics as an essential part of the phenomenological description of heavy-ion collisions at rhic and the lhc has motivated a significant body of theoretical work concerning its fundamental aspects. our review presents these developments from the perspective of the underlying microscopi...
new theories of relativistic hydrodynamics in the lhc era
we extend the perturbative double copy between radiating classical sources in gauge theory and gravity to the case of spinning particles. we construct, to linear order in spins, perturbative radiating solutions to the classical yang-mills equations sourced by a set of interacting color charges with chromomagnetic dipol...
spinning particles, axion radiation, and the classical double copy
in this paper, we study the von neumann entropy of hawking radiation sr for a d + 2-dimensional hyperscaling violating (hv) black brane which is coupled to two minkowski spacetimes as the thermal baths. we consider two different situations for the matter fields: first, they are described by a cftd+2 whose central charg...
entropy of hawking radiation for two-sided hyperscaling violating black branes
teleparallel gravity theories employ a tetrad and a lorentz spin connection as independent variables in their covariant formulation. in order to solve their field equations, it is helpful to search for solutions which exhibit certain amounts of symmetry, such as spherical or cosmological symmetry. in this article we pr...
modified teleparallel theories of gravity in symmetric spacetimes
<title>abstractfor a low energy effective theory to admit a standard local, unitary, analytic and lorentz-invariant uv completion, its scattering amplitudes must satisfy certain inequalities. while these bounds are known in the forward limit for real polarizations, any extension beyond this for particles with non...
uv complete me: positivity bounds for particles with spin
we give two double copy prescriptions which construct asymptotically flat solutions in gravity from asymptotically flat gauge fields. the first prescription applies to radiative fields, which are non-linear vacuum solutions determined by characteristic data at null infinity. for any two such radiative gauge fields (lin...
classical double copy at null infinity
nonrelativistic string theory in flat spacetime is described by a two-dimensional quantum field theory with a nonrelativistic global symmetry acting on the worldsheet fields. nonrelativistic string theory is unitary, ultraviolet complete and has a string spectrum and spacetime s-matrix enjoying nonrelativistic symmetry...
nonrelativistic string theory and t-duality
a number of diagrammatic "cutting rules" have recently been developed for the wavefunction of the universe which determines cosmological correlation functions. these leverage perturbative unitarity to relate particular "discontinuities" in feynman-witten diagrams (with cosmological boundary conditions) to simpler diagr...
the cosmological tree theorem
we drastically simplify the problem of linearizing a general higher-order theory of gravity. we reduce it to the evaluation of its lagrangian on a particular riemann tensor depending on two parameters, and the computation of two derivatives with respect to one of those parameters. we use our method to construct a d -di...
einsteinian cubic gravity
in [15] we proposed a generalization of the bms group which is a semi-direct product of supertranslations and smooth diffeomorphisms of the conformal sphere. although an extension of bms, is a symmetry group of asymptotically flat space times. by taking as a candidate symmetry group of the quantum gravity s-matrix, we ...
new symmetries for the gravitational s-matrix
we present a fully three-dimensional model providing initial conditions for energy and net-baryon density distributions in heavy-ion collisions at arbitrary collision energy. the model includes the dynamical deceleration of participating nucleons or valence quarks, depending on the implementation. the duration of the d...
dynamical initial-state model for relativistic heavy-ion collisions
grchombo is an open-source code for performing numerical relativity time evolutions, built on top of the publicly available chombo software for the solution of pdes. whilst grchombo uses standard techniques in nr, it focusses on applications in theoretical physics where adaptability, both in terms of grid structure, an...
grchombo: an adaptable numerical relativity code for fundamental physics
we disprove the widespread belief that higher order curvature theories of gravity in the metric-affine formalism are generally ghost-free. this is clarified by considering a sub-class of theories constructed only with the ricci tensor and showing that the non-projectively invariant sector propagates ghost-like degrees ...
ghosts in metric-affine higher order curvature gravity
in the semiclassical limit of de sitter gravity a separation of scales takes place that divides the theory into a "cosmic" sector and a "microscopic" sector. a similar separation takes place in the double-scaled limit of syk theory. we examine the scaling behaviors that accompany these limits and find parallels that su...
de sitter space, double-scaled syk, and the separation of scales in the semiclassical limit
the weyl double copy is a procedure for relating exact solutions in biadjoint scalar, gauge and gravity theories, and relates fields in spacetime directly. where this procedure comes from, and how general it is, have until recently remained mysterious. in this paper, we show how the current form and scope of the weyl d...
the weyl double copy from twistor space
asymptotically flat spacetimes have been studied in five separate regions: future/past timelike infinity $i^\pm$ , future/past null infinity $\mathcal{i}^\pm$ , and spatial infinity i 0. we formulate assumptions and definitions such that the five infinities share a single bondi-metzner-sachs (bms) group of asymptotic s...
an asymptotic framework for gravitational scattering
the present work studies one of einstein's alternative formulations based on the nonmetricity scalar q generalized as f (q ) theory. more specifically, we consider the power-law form of f (q ) gravity, i.e., f (q )=q +α qn. here, we analyze the behavior of the cosmological model at the background and perturbation level...
cosmological solutions and growth index of matter perturbations in f (q ) gravity
we explore the logarithmic terms in the soft theorem in four dimensions by analyzing classical scattering with generic incoming and outgoing states and one loop quantum scattering amplitudes. the classical and quantum results are consistent with each other. although most of our analysis in quantum theory is carried out...
classical and quantum results on logarithmic terms in the soft theorem in four dimensions
nonrelativistic string theory is described by a sigma model with a relativistic worldsheet and a nonrelativistic target spacetime geometry, that is called string newton-cartan geometry. in this paper we obtain string newton-cartan geometry as a limit of the riemannian geometry of general relativity with a fluxless two-...
string theory and string newton-cartan geometry
we perform a complete and systematic analysis of the solution space of six-dimensional einstein gravity. we show that a particular subclass of solutions — those that are analytic near i + — admit a non-trivial action of the generalised bondi-metzner-van der burg-sachs (gbms) group which contains infinite-dimensional su...
phase space renormalization and finite bms charges in six dimensions
we develop a general formalism for introducing stochastic fluctuations around thermodynamic equilibrium which takes into account, for the first time, recent developments in the causality and stability properties of relativistic hydrodynamic theories. the method is valid for any covariantly stable theory of relativistic...
stochastic fluctuations in relativistic fluids: causality, stability, and the information current
in this letter we consider a general quadratic parity-preserving theory for a general flat connection. imposing a local symmetry under the general linear group singles out the general teleparallel equivalent of general relativity carrying both torsion and non-metricity. we provide a detailed discussion on the teleparal...
general teleparallel quadratic gravity
relativity opens the door to a counterintuitive fact: a state can be stable to perturbations in one frame of reference and unstable in another one. for this reason, the job of testing the stability of states that are not lorentz invariant can be very cumbersome. we show that two observers can disagree on whether a stat...
can we make sense of dissipation without causality?
we find double-copy relations between classical radiating solutions in yang-mills theory coupled to dynamical color charges and their counterparts in a cubic bi-adjoint scalar field theory which interacts linearly with particles carrying bi-adjoint charge. the particular color-to-kinematics replacements we employ are m...
classical gluon and graviton radiation from the bi-adjoint scalar double copy
the double copy formalism provides an intriguing connection between gauge theories and gravity. it was first demonstrated in the perturbative context of scattering amplitudes but recently the formalism has been applied to exact classical solutions in gauge theories such as the monopole and instanton. in this paper we w...
s-duality and the double copy
the current interests in the universe motivate us to go beyond einstein's general theory of relativity. one of the interesting proposals comes from a new class of teleparallel gravity named symmetric teleparallel gravity, i.e., gravity, where the non-metricity term q is accountable for fundamental interaction. these al...
traversable wormhole geometries in gravity
we employ the minimal geometric deformation approach to gravitational decoupling (mgd-decoupling) in order to build an exact anisotropic version of the schwarzschild interior solution in a space-time with cosmological constant. contrary to the well-known schwarzschild interior, the matter density in the new solution is...
a causal schwarzschild-de sitter interior solution by gravitational decoupling
the vanishing affine connections have been used solely while adopting the modified f(q) gravity theory to the cosmology. consequently, researchers could not get beyond what is already known in f(t) theory earlier. to alleviate this problem, in the present manuscript we investigate a recently proposed construction of f(...
phase-space analysis of a novel cosmological model in f(q) theory
we identify in einstein gravity an asymptotic spin-2 charge aspect whose conservation equation gives rise, after quantization, to the sub-subleading soft theorem. our treatment reveals that this spin-2 charge generates a non-local spacetime symmetry represented at null infinity by pseudo-vector fields. moreover, we dem...
sub-subleading soft graviton theorem from asymptotic einstein's equations
we propose a technique to compute the deformation parameter of the generalized uncertainty principle by using the leading quantum corrections to the newtonian potential. we just assume general relativity as theory of gravitation, and the thermal nature of the gup corrections to the hawking spectrum. with these minimal ...
gup parameter from quantum corrections to the newtonian potential
the asymptotic safety scenario in gravity is accessed within the systematic vertex expansion scheme for functional renormalisation group flows put forward in christiansen et al. (phys lett b 728:114, 2014), christiansen et al. (phy rev d 93:044036, 2016), and implemented in christiansen et al. (phys rev d 92:121501, 20...
towards apparent convergence in asymptotically safe quantum gravity
we profit by a recent paper of visser claiming that rastall gravity is equivalent to einstein gravity to compare the two gravitational theories in a general way. our conclusions are different from visser's ones. we indeed argue that these two theories are not equivalent. in fact, rastall theory of gravity is an "open" ...
einstein and rastall theories of gravitation in comparison
we classify and relate unitary irreducible representations (uirs) of the carroll and dipole groups, i.e., we define elementary quantum carroll and fracton particles and establish a correspondence between them. whenever possible, we express the uirs in terms of fields on carroll/aristotle spacetime subject to their free...
quantum carroll/fracton particles
unimodular gravity (ug) is an alternative to general relativity (gr) which, however, is so closely related to the latter that one can wonder to what extent they are different. the different behaviour of the cosmological constant in the semiclassical regimes of both frameworks suggests the possible existence of addition...
unimodular gravity vs general relativity: a status report
we propose ħ-expansions as perturbative solutions of quantum extended snyder and yang models, with ħ-independent classical zero-th order terms responsible for the spontaneous breaking of d = 4 and d = 5 de sitter symmetries. in such models, with algebraic basis spanned by o ˆ (d , 1) lie algebra generators, we relate t...
quantum perturbative solutions of extended snyder and yang models with spontaneous symmetry breaking
in this work, we investigate the real-time dynamics of quenching a state from phase separation in a holographic model of first-order phase transition. in addition to the typical phase-separated and high-energy final states, we have discovered a novel dynamical process that drives the system to a low-temperature superco...
quench dynamics in holographic first-order phase transition