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Correlations and signaling in the Schrödinger–Newton model Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-20 Jacek Aleksander Gruca, Ankit Kumar, Ray Ganardi, Paramasivan Arumugam, Karolina Kropielnicka and Tomasz Paterek
The Schrödinger–Newton (SN) model is a semi-classical theory in which, in addition to mutual attraction, massive quantum particles interact with their own gravitational fields. While there are many studies on the phenomenology of single particles, correlation dynamics in multipartite systems is largely unexplored. Here, we show that the SN interactions preserve the product form of the initial state
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Existence and absence of Killing horizons in static solutions with symmetries Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-19 Hideki Maeda and Cristián Martínez
Without specifying a matter field nor imposing energy conditions, we study Killing horizons in -dimensional static solutions in general relativity with an -dimensional Einstein base manifold. Assuming linear relations and near a Killing horizon between the energy density ρ, radial pressure , and tangential pressure p2 of the matter field, we prove that any non-vacuum solution satisfying ( ) or does
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A rapid multi-modal parameter estimation technique for LISA Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-19 Charlie Hoy, Connor R Weaving, Laura K Nuttall and Ian Harry
The laser interferometer space antenna (LISA) will observe gravitational-wave (GW) signals from a wide range of sources, including massive black hole binaries (MBHBs). Although numerous techniques have been developed to perform Bayesian inference for LISA, they are often computationally expensive; analyses often take at least ∼1 month on a single CPU, even when using accelerated techniques. Not only
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Estimating false alarm rates of sub-dominant quasi-normal modes in GW190521 Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-18 Collin D Capano, Jahed Abedi, Shilpa Kastha, Alexander H Nitz, Julian Westerweck, Yi-Fan Wang, Miriam Cabero, Alex B Nielsen and Badri Krishnan
A major aim of gravitational wave astronomy is to test observationally the Kerr nature of black holes. The strongest such test, with minimal additional assumptions, is provided by observations of multiple ringdown modes, also known as black hole spectroscopy. For the gravitational wave merger event GW190521, we have previously claimed the detection of two ringdown modes emitted by the remnant black
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Strong-lensing cosmography using third-generation gravitational-wave detectors Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-18 Souvik Jana, Shasvath J Kapadia, Tejaswi Venumadhav, Surhud More and Parameswaran Ajith
We present a detailed exposition of a statistical method for estimating cosmological parameters from the observation of a large number of strongly lensed binary-black-hole (BBH) mergers observable by next (third) generation (XG) gravitational-wave (GW) detectors. This method, first presented in Jana (2023 Phys. Rev. Lett.130 261401), compares the observed number of strongly lensed GW events and their
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Charged Nariai black holes on the dark bubble Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-18 Ulf Danielsson and Vincent Van Hemelryck
In this paper, we realise the charged Nariai black hole on a braneworld from a nucleated bubble in AdS5, known as the dark bubble model. Geometrically, the black hole takes the form of a cylindrical spacetime pulling on the dark bubble. This is realised by a brane embedding in an AdS5 black string background. Identifying the brane with a D3-brane in string theory allows us to determine a relation between
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Suppression of clock-jitter noise and laser phase noise in arm locking Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-15 Zhang-Qi Wu, Pan-Pan Wang, Jun Ke and Cheng-Gang Shao
Arm-locking technique has been a focus of attention as one of the means to suppress the laser phase noise in space-based gravitational wave detector. The main idea of the arm-locking technique is to transfer the stability of the detector arm length to laser frequency by introducing a feedback control loop. Generally, laser phase noise will be suppressed by an amount similar to the magnitude of the
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Conversion of 30 W laser light at 1064 nm to 20 W at 2128 nm and comparison of relative power noise Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-15 Julian Gurs, Nina Bode, Christian Darsow-Fromm, Henning Vahlbruch, Pascal Gewecke, Sebastian Steinlechner, Benno Willke and Roman Schnabel
All current gravitational wave (GW) observatories operate with Nd:YAG lasers with a wavelength of 1064 nm. The sensitivity of future GW observatories could benefit significantly from changing the laser wavelength to approximately 2 µm combined with exchanging the current room temperature test mass mirrors with cryogenically cooled crystalline silicon test masses with mirror coatings from amorphous
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Role of decoupling and Rastall parameters on Krori–Barua and Tolman IV models generated by isotropization and complexity factor Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-13 Tayyab Naseer and M Sharif
We develop multiple analytical solutions to the Rastall field equations using a recently proposed scheme, named the gravitational decoupling. In order to do this, we assume a spherical distribution that possesses anisotropic pressure in its interior and extend it by incorporating an additional gravitating source through the corresponding Lagrangian density. Such addition in the initial fluid distribution
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Classical characters of spinor fields in torsion gravity Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-13 Luca Fabbri
We consider the problem of having relativistic quantum mechanics re-formulated with hydrodynamic variables, and specifically the problem of deriving the Mathisson–Papapetrou–Dixon equations (describing the motion of a massive spinning body moving in a gravitational field) from the Dirac equation. The problem will be answered on a general manifold with torsion and gravity. We will demonstrate that when
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The accelerating universe in a noncommutative analytically continued foliated quantum gravity Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-12 César A Zen Vasconcellos, Peter O Hess, José de Freitas Pacheco, Fridolin Weber, Benno Bodmann, Dimiter Hadjimichef, Geovane Naysinger, Marcelo Netz-Marzola and Moisés Razeira
Based on an analytically continued Riemannian foliated quantum gravity super-Hamiltonian, known as branch cut quantum gravity (BCQG) we propose a novel approach to investigating the effects of noncommutative geometry on a minisuperspace of variables, influencing the acceleration behavior of the Universe’s wave function and the cosmic scale factor. Noncommutativity is introduced through a deformation
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On the role of fiducial structures in minisuperspace reduction and quantum fluctuations in LQC Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-12 Fabio M Mele and Johannes Münch
In spatially non-compact homogeneous minisuperpace models, spatial integrals in the Hamiltonian and symplectic form must be regularised by confining them to a finite volume Vo, known as the fiducial cell. As this restriction is unnecessary in the complete field theory before homogeneous reduction, the physical significance of the fiducial cell has been largely debated, especially in the context of
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Binary neutron star mergers using a discontinuous Galerkin-finite difference hybrid method Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-11 Nils Deppe, Francois Foucart, Marceline S Bonilla, Michael Boyle, Nicholas J Corso, Matthew D Duez, Matthew Giesler, François Hébert, Lawrence E Kidder, Yoonsoo Kim, Prayush Kumar, Isaac Legred, Geoffrey Lovelace, Elias R Most, Jordan Moxon, Kyle C Nelli, Harald P Pfeiffer, Mark A Scheel, Saul A Teukolsky, William Throwe and Nils L Vu
We present a discontinuous Galerkin-finite difference hybrid scheme that allows high-order shock capturing with the discontinuous Galerkin method for general relativistic magnetohydrodynamics in dynamical spacetimes. We present several optimizations and stability improvements to our algorithm that allow the hybrid method to successfully simulate single, rotating, and binary neutron stars. The hybrid
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Characterizing gravitational wave detector networks: from A ♯ to cosmic explorer Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-08 Ish Gupta, Chaitanya Afle, K G Arun, Ananya Bandopadhyay, Masha Baryakhtar, Sylvia Biscoveanu, Ssohrab Borhanian, Floor Broekgaarden, Alessandra Corsi, Arnab Dhani, Matthew Evans, Evan D Hall, Otto A Hannuksela, Keisi Kacanja, Rahul Kashyap, Sanika Khadkikar, Kevin Kuns, Tjonnie G F Li, Andrew L Miller, Alexander Harvey Nitz, Benjamin J Owen, Cristiano Palomba, Anthony Pearce, Hemantakumar Phurailatpam
Gravitational-wave observations by the laser interferometer gravitational-wave observatory (LIGO) and Virgo have provided us a new tool to explore the Universe on all scales from nuclear physics to the cosmos and have the massive potential to further impact fundamental physics, astrophysics, and cosmology for decades to come. In this paper we have studied the science capabilities of a network of LIGO
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Towards the solution of coating loss measurements using thermoelastic-dominated substrates Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-07 L Silenzi, F Fabrizi, M Granata, L Mereni, M Montani, F Piergiovanni, A Trapananti, F Travasso, G Cagnoli
The characterization of thin film parameters derives from the measurement difference between the coated and bare substrate. This method of comparison is based on the stationarity of the substrate: the characteristics of the substrate do not depend on the presence of the film. However, the thermoelastic loss of a coated substrate depends on the thermo-mechanical parameters of the film as well, which
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Dynamical system analysis in modified Galileon cosmology Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-07 L K Duchaniya, B Mishra, I V Fomin, S V Chervon
In this paper, we have investigated the phase space analysis in modified Galileon cosmology, where the Galileon term is considered a coupled scalar field, F(ϕ). We focus on the exponential type function of F(ϕ) and the three well-motivated potential functions V(ϕ). We obtain the critical points of the autonomous system, along with their stability conditions and cosmological properties. The critical
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On the convergence of cosmographic expansions in Lemaître–Tolman–Bondi models Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-07 Asha B Modan, S M Koksbang
We study cosmographic expansions of the luminosity distance for a variety of Lemaître–Tolman–Bondi (LTB) models which we specify inspired by local large-scale structures of the Universe. We consider cosmographic expansions valid for general spacetimes and compare to the Friedmann–Lemaître–Robertson–Walker (FLRW) limit of the expansions as well as to its naive isotropic extrapolation to an inhomogeneous
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The pseudospectrum and transient of Kaluza–Klein black holes in Einstein–Gauss–Bonnet gravity Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-06 Jia-Ning Chen, Liang-Bi Wu, Zong-Kuan Guo
The spectrum and dynamical instability, as well as the transient effect of the tensor perturbation for the so-called Maeda–Dadhich black hole, a type of Kaluza–Klein black hole, in Einstein–Gauss–Bonnet gravity have been investigated in framework of pseudospectrum. We cast the problem of solving quasinormal modes (QNMs) in AdS-like spacetime as the linear evolution problem of the non-normal operator
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The model of the local Universe in the framework of the second-order perturbation theory Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-06 Szymon Sikora, Jan J Ostrowski
Recently, we constructed the specific solution to the second-order cosmological perturbation theory, around any Friedmann–Lemaître–Robertson–Walker background filled with dust matter and a positive cosmological constant. In this paper, we use the Cosmicflows-4 sample of galaxies from the Extragalactic Distance Database to constrain this metric tensor. We obtain an approximation to the local matter
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Dynamical friction in rotating ultralight dark matter galactic cores Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-06 V M Gorkavenko, O V Barabash, T V Gorkavenko, O M Teslyk, A O Zaporozhchenko, Junji Jia, A I Yakimenko, E V Gorbar
Dynamical friction and stellar orbital motion in spiral galaxies with dark matter composed of ultralight bosons in the state of rotating Bose–Einstein condensate (BEC) are studied. It is found that the dynamical friction force is significantly affected by the topological charge of the vortex structure of the BEC core with the strongest effect at distances near the galactic center. It is also shown
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Gauge invariant perturbations of static spatially compact LRS II spacetimes Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-06 Paulo Luz, Sante Carloni
We present a framework to describe completely general first-order perturbations of static, spatially compact, and locally rotationally symmetric class II spacetimes within the theory of general relativity. The perturbation variables are by construction covariant and identification gauge invariant and encompass the geometry and the thermodynamics of the fluid sources. The new equations are then applied
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The universal thermodynamic properties of extremely compact objects Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-05 Samir D Mathur, Madhur Mehta
An extremely compact object (ECO) is defined as a quantum object without horizon, whose radius is just a small distance s outside its Schwarzschild radius. We show that any ECO of mass M in d + 1 dimensions with s≪(M/mp)2/(d−2)(d+1)lp must have (at leading order) the same thermodynamic properties—temperature, entropy and radiation rates—as the corresponding semiclassical black hole of mass M. An essential
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Gauss–Bonnet AdS planar and spherical black hole thermodynamics and holography Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-05 Souvik Paul, Sunandan Gangopadhyay, Ashis Saha
In this work, we extend the study in Bilic and Fabris (2022 J. High Energy Phys. JHEP11(2022)013) incorporating the AdS/CFT duality to establish a relationship between the local temperatures (Tolman temperatures) of a large (AdS) spherical and a (AdS) planar Schwarzschild black hole near the AdS boundary considering Gauss–Bonnet (GB) curvature correction in the gravitational action. We have shown that
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Effective Lifshitz black holes, hydrodynamics, and transport coefficients in fluid/gravity correspondence Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-04 D C Moreira, R da Rocha
Effective Lifshitz black holes with arbitrary dynamical exponent are addressed in the fluid/gravity membrane paradigm. The transport and the response coefficients in the dual Lifshitz field theory are calculated and analyzed, including the charge diffusion constant and the shear mode damping constant, along with the shear-viscosity-to-entropy density ratio. The Kubo formula is employed to obtain the
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Quantum gravity phenomenology and the blackbody radiation Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-04 R Turcati, I Soares, S B Duarte
We analyze the blackbody radiation problem in the presence of quantum gravity effects encoded in modified dispersion relations. The spectral radiance and the generalized Stefan–Boltzmann law are studied in this context. Furthermore, the regime of low temperatures is also contemplated, where features related to the blackbody thermal laws and the thermodynamic quantities such as energy, pressure, entropy
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On the nonequilibrium dynamics of gravitational algebras Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-01 Michele Cirafici
We explore nonequilibrium features of certain operator algebras which appear in quantum gravity. The algebra of observables in a black hole background is a Type II∞ von Neumann algebra. We discuss how this algebra can be coupled to the algebra of observable of an infinite reservoir within the canonical ensemble, aiming to induce nonequilibrium dynamics. The resulting dynamics can lead the system towards
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General relativistic gravitational induction and causal temperatures Classical Quant. Grav. (IF 3.6) Pub Date : 2024-11-01 Jonathan Hakata, Rituparno Goswami, Chevarra Hansraj, Sunil D Maharaj
In this paper, we describe the process of general relativistic gravitational induction in spherically symmetric spacetimes by defining an energy momentum tensor for the induction process, which is divergence-free and hence conserved. The aforementioned tensor explicitly describes how the matter-free gravity, as measured by the geometrical Weyl curvature, interacts with the matter. This tensor is clearly
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Schrödinger connections: from mathematical foundations towards Yano–Schrödinger cosmology Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-30 Lehel Csillag, Anish Agashe, Damianos Iosifidis
Schrödinger connections are a special class of affine connections, which despite being metric incompatible, preserve length of vectors under autoparallel transport. In the present paper, we introduce a novel coordinate-free formulation of Schrödinger connections. After recasting their basic properties in the language of differential geometry, we show that Schrödinger connections can be realized through
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Spherical accretion onto higher-dimensional Reissner–Nordström black hole Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-30 Bibhash Das, Anirban Chanda, Bikash Chandra Paul
We obtain relativistic solutions of spherically symmetric accretion by a dynamical analysis of a generalised Hamiltonian for higher-dimensional Reissner–Nordström (RN) Black Hole (BH). We consider two different fluids namely, an isotropic fluid and a non-linear polytropic fluid to analyse the critical points in a higher-dimensional RN BH. The flow dynamics of the fluids are studied in different spacetime
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Relativistic fluids in cosmological spacetimes Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-29 David Fajman, Maximilian Ofner, Zoe Wyatt
We review the status of mathematical research on the dynamical properties of relativistic fluids in cosmological spacetimes–both, in the presence of gravitational backreaction as well as the evolution on fixed cosmological backgrounds. We focus in particular on the phenomenon of fluid stabilization, which describes the taming effect of spacetime expansion on the fluid. While fluids are in general known
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The Virgo Newtonian calibration system for the O4 observing run Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-29 F Aubin, E Dangelser, D Estevez, A Masserot, B Mours, T Pradier, A Syx, P Van Hove
After initial tests performed during previous observing runs, a Newtonian calibrator (NCal) system was developed and installed on the Virgo gravitational wave detector for the O4 observing run. This system, which is continuously operated, provides the absolute calibration of Virgo for this run. Its 1-σ uncertainty of 0.17% on the amplitudes of the injected signals is better than that obtained with
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Mass octupole and current quadrupole corrections to gravitational wave emission from close hyperbolic encounters Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-25 Alexander Roskill, Marienza Caldarola, Sachiko Kuroyanagi, Savvas Nesseris
In this paper, we study the next-to-leading order corrections in the mass multipole expansion, i.e. the mass octupole and current quadrupole, to gravitational wave production by close hyperbolic encounters of compact objects. We find that the signal is again, as in the simple quadrupole case, a burst event with the majority of the released energy occurring during the closest approach. In particular
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Deflection of light by wormholes and its shadow due to dark matter within modified symmetric teleparallel gravity formalism Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-25 G Mustafa, Zinnat Hassan, P K Sahoo
We explore the possibility of traversable wormhole formation in the dark matter halos in the context of f(Q) gravity. We obtain the exact wormhole solutions with anisotropic matter source based on the Bose–Einstein condensate, Navarro-Frenk-White, and pseudo-isothermal matter density profiles. Notably, we present a novel wormhole solution supported by these dark matters using the expressions for the
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Atomic electron transitions of hydrogen-like atoms induced by gravitational waves Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-23 Bo-Hung Chen, Dah-Wei Chiou
As a realistic model of a quantum system of matter, this paper investigates the gravitational-wave effects on a hydrogen-like atom using a first-principles approach. By formulating the tetrad formalism of linearized gravity, we naturally incorporate gravitational-wave effects through minimal coupling in the covariant Dirac equation. The atomic electron transition rates induced by the gravitational
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Non-linear charged dS spacetime and its thermodynamics and Schottky Anomaly Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-23 Hai-Long Zhen, Yun-Zhi Du, Huai-Fan Li, Li-Chun Zhang, Yu-Bo Ma
In this paper, firstly, the conditions and existence region for the coexistence of the black hole and cosmological horizons in Non-linear charged dS (NLC-dS) spacetime are discussed, subsequently, the thermodynamic quantities for which the boundary conditions are satisfied in spacetime in the coexistence region of the two horizons are discussed, and the effective thermodynamic quantities in the NLC-dS
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Efficient Bayesian inference and model selection for continuous gravitational waves in pulsar timing array data Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-23 Bence Bécsy
Finding and characterizing gravitational waves from individual supermassive black hole binaries is a central goal of pulsar timing array experiments, which will require analysis methods that can be efficient on our rapidly growing datasets. Here we present a novel approach built on three key elements: (i) precalculating and interpolating expensive matrix operations; (ii) semi-analytically marginalizing
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Anomalous higher order Ward identities in tensorial group field theories without closure constraint Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-22 Bio Wahabou Kpera, Vincent Lahoche, Dine Ousmane Samary, Seke Fawaaz Zime Yerima
The Ward–Takahashi identities are considered as the generalization of the Noether currents available to quantum field theory and include quantum fluctuation effects. Usually, they take the form of relations between correlation functions, which ultimately correspond to the relation between coupling constants of the theory. For this reason, they play a central role in the construction of renormalized
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A review of gravitational memory and BMS frame fixing in numerical relativity Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-22 Keefe Mitman, Michael Boyle, Leo C Stein, Nils Deppe, Lawrence E Kidder, Jordan Moxon, Harald P Pfeiffer, Mark A Scheel, Saul A Teukolsky, William Throwe, Nils L Vu
Gravitational memory effects and the BMS freedoms exhibited at future null infinity have recently been resolved and utilized in numerical relativity simulations. With this, gravitational wave models and our understanding of the fundamental nature of general relativity have been vastly improved. In this paper, we review the history and intuition behind memory effects and BMS symmetries, how they manifest
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Towards quantum gravity with neural networks: solving the quantum Hamilton constraint of U(1) BF theory Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-22 Hanno Sahlmann, Waleed Sherif
In the canonical approach of loop quantum gravity, arguably the most important outstanding problem is finding and interpreting solutions to the Hamiltonian constraint. In this work, we demonstrate that methods of machine learning are in principle applicable to this problem. We consider U(1) BF theory in three dimensions, quantised with loop quantum gravity methods. In particular, we formulate a master
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Self-gravitating matter in stationary and axisymmetric black hole spacetimes Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-21 Prashant Kocherlakota, Ramesh Narayan
All black holes (BHs) in nature are expected to be described by the Kerr vacuum solution of general relativity. However, the Kerr BH interior contains several problematic features such as a Cauchy horizon, a curvature singularity, and a causality-violating region. Non-Kerr BH models, which are used to examine the genericity of these features, typically contain nontrivial matter content. When such self-gravitating
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de Sitter Teukolsky waves Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-21 Harsh1harsh22@cmi.ac.in, Sk Jahanur Hoque, Sitender Pratap Kashyap, Amitabh Virmani
We present de Sitter Teukolsky waves—linearised quadrupolar gravitational waves in the transverse-traceless gauge in de Sitter spacetime. In the cosmological constant Λ going to zero limit, our solutions match to Teukolsky solutions. For non-zero Λ, we compare our solutions to the wider literature, where different authors have constructed linearised gravitational perturbations in de Sitter spacetime
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Two-dimensional (bi-)scalar gravities from four-dimensional Horndeski Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-21 M Shams Nejati, M H Vahidinia
We develop a classical two-dimensional bi-scalar gravity based on the Kaluza–Klein reduction applied to the four-dimensional Horndeski theory. One of the scalar fields arises from the original four-dimensional theory, while the extra scalar emerges from the reduction process. We also introduce a two-dimensional bi-scalar identity that allows for a more concise and elegant reformulation of the resulting
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A natural model for curved inflation Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-21 Quentin Vigneron, Julien Larena
Inflationary models with a non-zero background curvature require additional hypothesis or parameters compared to flat inflation and the procedure to construct them cannot be as simple as in the flat case. For this reason, there is no consensus on the primordial power spectrum that should be considered at large scales in a curved Universe. In this letter, we propose a model of curved inflation in which
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Spin-2 Green’s functions on Kerr in radiation gauge Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-18 Marc Casals, Stefan Hollands, Adam Pound, Vahid Toomani
We construct retarded and advanced Green’s functions for gravitational perturbations in Kerr in an ingoing radiation gauge. Our Green’s functions have a frequency domain piece that has previously been obtained by Ori (2003 Phys. Rev. D 67) based on the Chrzanowski-Cohen-Kegeles metric reconstruction method. As is well known, this piece by itself is not sufficient to obtain an actual Green’s function
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Hopfion-like solutions in de Sitter spacetime Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-18 Adam Grzela, Jacek Jezierski, Tomasz Smołka
We construct electromagnetic field with non-trivial topological properties on de Sitter background. The field is closely related with Hopf fibration. We analyze energy, angular momentum and topological charges for this solution. The paper is a generalization of Smołka and Jezierski (2018 Class. Quantum Grav. 35 245010) to de Sitter spacetime.
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An experiment to measure electromagnetic memory Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-18 Lydia Bieri, David Garfinkle
We describe an experiment to measure the electromagnetic analog of gravitational wave memory, the so-called electromagnetic (EM) memory. Whereas gravitational wave memory is a residual displacement of test masses, EM memory is a residual velocity (i.e. kick) of test charges. The source of gravitational wave memory is energy that is not confined to any bounded spatial region: in the case of binary black
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Boosted Kerr–Newman black holes Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-17 Rafael F Aranha, Rodrigo Maier
In this paper we obtain a new solution of Einstein field equations which describes a boosted Kerr–Newman black hole relative to a Lorentz frame at future null infinity. To simplify our analysis we consider a particular configuration in which the boost is aligned with the black hole angular momentum. The boosted Kerr–Newman black hole is obtained considering the complete asymptotic Lorentz transformations
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Boosting gravitational waves: a review of kinematic effects on amplitude, polarization, frequency and energy density Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-16 Giulia Cusin, Cyril Pitrou, Camille Bonvin, Aurélien Barrau, Killian Martineau
We review the kinematic effects on a gravitational wave due to either a peculiar motion of the astrophysical source emitting it or a local motion of the observer. Working in the context of general relativity, we show at fully non-linear order in velocity, that the amplitude of the wave is amplified by the Doppler factor in the case in which the source moves with respect to a reference frame, while
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Quantum and classical properties of the Universe according to unimodular quantum cosmology Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-16 Natascha Riahi
We investigate the dynamical behavior of wavepacket solutions due to unimodular quantum cosmology. We find early and late time quantum eras of the Universe. An Ehrenfest theorem ensures quasi-classical behavior for the late time Universe if the quantum uncertainties are small. The surprising prediction of late time quantum effects for a flat, homogeneous and isotropic Universe with a scalar field with
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Estimate of in-band eddy current effect in space gravitational wave detection Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-16 Jia-Hao Xu, Li-Na Zhang, Jun Ke, Cheng-Zong Li, Wen-Long Ma
In space detection of gravitational waves (GWs), the presence of a low-frequency varying magnetic field will generate eddy currents in the test mass, resulting in a varying magnetic moment. This magnetic moment will couple with a constant magnetic field gradient, producing residual acceleration within the frequency band of GW detection, causing the test mass to deviate from the free-falling mode. However
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Comparison of arm cavity optical losses for the two wavelengths of the Einstein telescope gravitational wave detector Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-15 Maxime Le Jean, Jerome Degallaix, David Hofman, Laurent Pinard, Danièle Forest, Massimo Granata, Christophe Michel, Jessica Steinlechner, Claude Amra, Michel Lequime, Myriam Zerrad
A new generation of gravitational wave detectors is currently being designed with the likely use of a different laser wavelength compared to current instruments. The estimation of the optical losses for this new wavelength is particularly relevant to derive the detector sensitivity and also to anticipate the optical performances of future instruments. In this article, we measured the absorption and
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Measuring neutron star radius with second and third generation gravitational wave detector networks Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-15 Ananya Bandopadhyay, Keisi Kacanja, Rahul Somasundaram, Alexander H Nitz, Duncan A Brown
The next generation of ground-based interferometric gravitational wave detectors will observe mergers of black holes and neutron stars throughout cosmic time. A large number of the binary neutron star merger events will be observed with extreme high fidelity, and will provide stringent constraints on the equation of state of nuclear matter. In this paper, we investigate the systematic improvement in
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Fast inspirals and the treatment of orbital resonances Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-14 Philip Lynch, Vojtěch Witzany, Maarten van de Meent, Niels Warburton
Extreme mass ratio inspirals (EMRIs), where a compact object orbits a massive black hole, are a key source of gravitational waves for the future Laser Interferometer Space Antenna (LISA). Due to their small mass ratio, ( ϵ∼10−4–10−7), the binary evolves slowly and EMRI signals will be in-band for years. Additionally, astrophysical EMRIs are expected to have complex dynamics featuring both spin-precession
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Analytical solutions to the cylindrically symmetric compressible isothermal Euler–Poisson equations of galaxies Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-14 Qiao Zhang, Jianwei Dong
In this paper, we study the cylindrically symmetric compressible isothermal Euler–Poisson equations of galaxies with a negative cosmological constant. By using some ansatzes, we construct a family of analytical periodic solutions to the system, which partially complements the result in Yuen (2009 Class. Quantum Grav. 26 235011), where a family of analytical periodic solutions to the system with spherical
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Torsional regularization of self-energy and bare mass of electron Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-11 Michael Del Grosso, Nikodem Popławski
In the presence of spacetime torsion, the momentum components do not commute; therefore, in quantum field theory, summation over the momentum eigenvalues will replace integration over the momentum. In the Einstein–Cartan theory of gravity, in which torsion is coupled to spin, the separation between the eigenvalues increases with the magnitude of the momentum. Consequently, this replacement regularizes
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KSW criterion in large field models Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-11 Oliver Janssen
We extend the analytic description of complex no-boundary solutions in the context of inflation to large field models. We discuss the Kontsevich–Segal–Witten (KSW) criterion and find it is satisfied in small field models, while in large field models it depends on an integral involving V′(ϕ) over the range of inflation. It follows that although particular models are ruled out, e.g. quadratic inflation
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Feasibility of loop-gain tuning for general measurement systems inspired by quantum locking for DECIGO Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-10 T Ishikawa, Y Kawasaki, K Tsuji, R Shimizu, K Umemura, B Wu, S Iwaguchi, Y Michimura, K Nagano, Y Enomoto, K Komori, S Doki, A Furusawa, S Kawamura
A series of quantum locking theories have been proposed to enhance the quantum-noise-limited target sensitivity of the DECi-hertz Interferometer Gravitational wave Observatory. The quantum locking that uses a square completion optimizes the sensitivity across all frequencies. However, a substantial amount of data-series must be post-processed since the square completion is a form of signal processing
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Finiteness of 3D higher spin gravity Landscape Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-10 Rajae Sammani, Youssra Boujakhrout, El Hassan Saidi, Rachid Ahl Laamara, Lalla Btissam Drissi
We give Swampland constraints on the three dimensional Landscape of Anti-de Sitter higher spin gravity in the Chern–Simons formulation with connection valued in various split real forms of Lie algebras. We derive the finiteness conjecture by computing the upper bound on the rank of possible gauge groups then we refine it using the AdS distance conjecture. We discuss the implications of this Swampland
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Graviton-photon oscillations as a probe of quantum gravity Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-10 Andrea Palessandro
The Gertsenshtein effect could in principle be used to detect a single graviton by firing it through a region filled with a constant magnetic field that enables its conversion to a photon, which can be efficiently detected via standard techniques. The quantization of the gravitational field could then be inferred indirectly. We show that for currently available single-photon detector technology, the
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Smooth Gowdy-symmetric generalised Taub–NUT solutions with polynomial initial data Classical Quant. Grav. (IF 3.6) Pub Date : 2024-10-09 Jörg Hennig
We consider smooth Gowdy-symmetric generalised Taub–NUT solutions, a class of inhomogeneous cosmological models with spatial three-sphere topology. They are characterised by existence of a smooth past Cauchy horizon and, with the exception of certain singular cases, they also develop a regular future Cauchy horizon. Several examples of exact solutions were previously constructed, where the initial