Tootfinder

Some geometrical aspects of gravitational waves using continuum mechanics analogy: State of the art and potential consequences
David Izabel, Yves Remond, Matteo Luca Ruggiero
https://arxiv.org/abs/2508.09279

Some geometrical aspects of gravitational waves using continuum mechanics analogy: State of the art and potential consequences
In this study, the authors employ the analogy between continuum mechanics and general relativity to investigate, from the perspective of elasticity and crystal plasticity, the deformations of space measured by LIGO/VIRGO interferometers during the passage of gravitational waves over Earth. The results of different innovative or existing mechanical models are compared with each other and compared with the observations in the framework of general relativity and Einstein-Cartan theory. Despite lim…

The charge-singlet measurement toolbox
Abhijit Chakraborty, Randy Lewis, Christine A. Muschik
https://arxiv.org/abs/2510.08718 https://arxiv.org/pdf/2510.0…

The charge-singlet measurement toolbox
Symmetry is fundamental to physical laws across different scales$\unicode{x2014}$from spacetime structure in general relativity to particle interactions in quantum field theory. Local symmetries, described by gauge theories, are central to phenomena such as superconductivity, topological phases, and the Standard Model of particle physics. Emerging simulation techniques using tensor network states or quantum computers offer exciting new possibilities of exploring the physics of these gauge theor…

Foundational Structure of Local Amplitudes in Quantum Gravity
Charalampos Theofilis, Wolfgang Wieland
https://arxiv.org/abs/2508.09679 https://arxiv.org/pd…

Foundational Structure of Local Amplitudes in Quantum Gravity
There has been recently renewed interest in the quantisation of gravity by considering local subsystems on light-like hypersurfaces. The main purpose of this paper is to present a theory-independent perspective on these developments assuming only basic knowledge of quantum theory and general relativity. In addition, we present a top-down approach to constructing local amplitudes in causal diamonds. The fundamental building block is a slab of light-like geometry (e.g. a segment of a light cone e…

Sandwich Construction of Symmetry TFTs for the Centre Symmetries of Chern-Simons, Yang-Mills, and Einstein Gravity
Leron Borsten, Dimitri Kanakaris, Hyungrok Kim
https://arxiv.org/abs/2509.08819

Sandwich Construction of Symmetry TFTs for the Centre Symmetries of Chern-Simons, Yang-Mills, and Einstein Gravity
We construct symmetry topological field theories (SymTFTs) using the sandwich construction of Pulmann-Ševera-Valach that manifest the centre symmetries of Chern-Simons theory and Yang-Mills theory as well as general relativity in the MacDowell-Mansouri formulation. The 'filling' of the sandwich is an AKSZ sigma model whose target space is a Weil algebra, augmented with discrete degrees of freedom given by a choice of topological boundary condition.

Isentropic processes for axisymmetric Black Holes
Nitesh K. Dubey, Sanved Kolekar
https://arxiv.org/abs/2507.08547 https://arxiv.org/…

Isentropic processes for axisymmetric Black Holes
We demonstrate that the isentropic absorption of a classical charged test particle is classically forbidden for all 3+1 dimensional stationary, non-extremal, axisymmetric black holes in any diffeomorphism invariant theory of gravity. This result is derived purely from the near-horizon geometry and thermodynamic properties of the black hole spacetime, independent of the specific gravitational theory. We further consider the Kerr-Newman black hole in general relativity and analyze within the semi…

Relativity of Time in Earthquake Physics
A. V. Guglielmi, O. D. Zotov
https://arxiv.org/abs/2509.04858 https://arxiv.org/pdf/2509.04858

Relativity of Time in Earthquake Physics
In this paper we develop an understanding of the proper time of the Tohoku earthquake source. The paper is dedicated to the 120th anniversary of Einstein's theory of relativity, but the dedication is symbolic, since we are investigating a purely non-relativistic geophysical object. We still found it possible to borrow the terms time relativity and proper time from the theory of relativity. The concept of the proper time of the source is developed by us within the framework of the phenomenologic…

Thermodynamics of Einstein-Geometric Proca AdS compact objects
Asalkhon Alimova, Elham Ghorani, Beyhan Puli\c{c}e, Farruh Atamurotov, Ahmadjon Abdujabbarov
https://arxiv.org/abs/2509.09389

Thermodynamics of Einstein-Geometric Proca AdS compact objects
In this study we explore metric-Palatini gravity extended by the antisymmetric component of the affine curvature. This gravitational theory results in general relativity plus a geometric Proca field. Building on our previous work, where we constructed its static spherically symmetric solutions in the Anti-de Sitter (AdS) background (Eur. Phys. J. C 83(4):318, 2023), we conduct a comprehensive analysis of the system's thermodynamics. We examine the thermodynamic properties of the Einstein-Geomet…

On Andr\'eka's Conjecture that special relativity is the only possible conceptual reduct of classical kinematics
Judit Madar\'asz, Mike Stannett, Gergely Sz\'ekely
https://arxiv.org/abs/2507.21180

On Andréka's Conjecture that special relativity is the only possible conceptual reduct of classical kinematics
In this paper, we prove a pure mathematical result which has important implications for the history and philosophy of classical physics and the conceptual origins of relativity theory. In formal terms, we show that, up to definitional equivalence, there is no intermediate model of spacetime lying strictly between special relativity and late classical kinematics. Informally, this means that there was essentially no other option but to switch to special relativity to resolve the conflict between …

Precision gravity constraints on large dark sectors
Christopher Ewasiuk, Stefano Profumo
https://arxiv.org/abs/2509.02801 https://arxiv.org/pdf/2509.02801

Precision gravity constraints on large dark sectors
General relativity, treated as a low-energy effective field theory, predicts quantum corrections to Newton's law of gravitation arising from loops of matter and graviton fields. While these corrections are utterly negligible when considering the Standard Model particle content, the situation changes dramatically in the presence of a hidden or dark sector containing a very large number of light degrees of freedom. In such cases, loop-induced modifications to the Newtonian potential can accumulat…

General Relativity in IIB Matrix Model
Pei-Ming Ho, Hikaru Kawai, Harold C. Steinacker
https://arxiv.org/abs/2509.06646 https://arxiv.org/pdf/2509.06646

General Relativity in IIB Matrix Model
The matrix models are non-perturbative formulations of string theory, from which many believe that spacetime arises. The matrix fluctuations around the spacetime thus created should represent both matter and gravitational fields. In this paper, we discuss how the gravitational field emerges from the IIB matrix model. In particular, we consider how diffeomorphism invariance arises and how unitarity is guaranteed in this theory. Specifically, we consider matrices as bilocal fields and discuss how…

Stable Islands of Weak Gravity
Linus Thummel, Benjamin Bose, Alkistis Pourtsidou
https://arxiv.org/abs/2508.05729 https://arxiv.org/pdf/2508.05729

Stable Islands of Weak Gravity
We present an exploration of the phenomenology of Horndeski gravity, focusing on regimes that produce weak gravity compared to General Relativity. This letter introduces a novel method to generate models of modified gravity theories that produce a specific observational behaviour while fulfilling stability criteria, without imposing a fixed parametrisation. We start from the inherently stable basis of linear Horndeski theory, implemented in the recently released Einstein-Boltzmann solver mochi_…

Pascual Jordan's "Erweiterte Gravitationstheorie" - A Historical Analysis of its Mathematical Framework
Bernadette Lessel
https://arxiv.org/abs/2507.23758 https://…

Pascual Jordan's "Erweiterte Gravitationstheorie" - A Historical Analysis of its Mathematical Framework
This paper aims to highlight Pascual Jordan's axiomatic definition of the covariant derivative, as set out in his 1952 textbook "Schwerkraft und Weltall". Developed in light of his \emph{Erweiterte Gravitationstheorie} - a projective reformulation of relativity theory that incorporates a variable gravitational constant - Jordan's definition resembles those in contemporary usage. The paper contextualises Jordan's work within the broader historical frameworks of differential geometry and projecti…

Dwarf galaxies in non-local gravity
Ivan De Martino, Riccardo Della Monica, Mahmood Roshan
https://arxiv.org/abs/2507.21986 https://arxiv.org/pdf/2507.2198…

Dwarf galaxies in non-local gravity
The nature of dark matter remains one of the most pressing open questions in modern cosmology. Despite extensive experimental efforts, no direct or indirect detection of dark matter particles has been confirmed. This has motivated alternative approaches, including modifications to the underlying theory of gravity. In this work, we investigate the implications of a specific non-local gravity (NLG) theory, which modifies General Relativity by introducing non-local effects that manifest as an effe…

Conformal Gravity as a Deformed Topological Field Theory
James A. Reid
https://arxiv.org/abs/2508.05683 https://arxiv.org/pdf/2508.05683

Conformal Gravity as a Deformed Topological Field Theory
In the MacDowell-Mansouri formulation of general relativity, the spin connection and coframe variables are incorporated into a single Lie algebra-valued connection called the MacDowell-Mansouri connection, $ω$. From the curvature form $F$ of $ω$ and an auxiliary field, $B$, one may formulate general relativity as a deformed topological field theory by constructing an action functional whose variation yields a set of field equations that are equivalent to the Einstein equations on shell. In th…

On the Determination of Collisional Stopping Power via Kaluza-Klein Theory
Seyda Elife G\"on\"ul, Huriye G\"ursel
https://arxiv.org/abs/2508.05701 https://…

On the Determination of Collisional Stopping Power via Kaluza-Klein Theory
In this work, the tools of general relativity are used to analytically derive collisional stopping power. We start from a Kaluza-Klein inspired, five-dimensional diffeomorphism-invariant action, and upon compactification, obtain a four-dimensional effective theory in which the matter fields are treated to be brane-localized. The medium response to the projected electron is encoded in symmetric tensor fields coupled covariantly to both electromagnetic and fermionic parts via Lagrangian-derived i…

Einstein's Hidden Scaffolding, with a Glance at Poincar\'e
Galina Weinstein
https://arxiv.org/abs/2509.02456 https://arxiv.org/pdf/2509.02456

Einstein's Hidden Scaffolding, with a Glance at Poincaré
This paper reconstructs the derivations underlying the kinematical part of Einstein's 1905 special relativity paper, emphasizing their operational clarity and minimalist use of mathematics. Einstein employed modest tools-algebraic manipulations, Taylor expansions, partial differentials, and functional arguments-yet his method was guided by principles of linearity, symmetry, and invariance rather than the elaborate frameworks of electron theory. The published text in "Annalen der Physik" conceal…

Reconciling Inflation with Hubble Anisotropies
Brett McInnes
https://arxiv.org/abs/2508.06796 https://arxiv.org/pdf/2508.06796

Reconciling Inflation with Hubble Anisotropies
There have been persistent suggestions, based on several diverse data sets, that the cosmic expansion is not exactly isotropic. It is not easy to develop a coherent theoretical account of such a ``Hubble anisotropy'', for, in standard General Relativity, intuition suggests that it contradicts the predictions of the very successful Inflationary hypothesis. We put this intuition on a firm basis, by proving that if we [a] make use of an Inflationary theory in which Inflation isotropises spatial ge…

Design of high-efficiency UHV loading of nanodiamonds into a Paul trap: Towards Matter-Wave Interferometry with Massive Objects
Rafael Benjaminov, Sela Liran, Or Dobkowski, Yaniv Bar-Haim, Michael Averbukh, Ron Folman
https://arxiv.org/abs/2508.14722

Design of high-efficiency UHV loading of nanodiamonds into a Paul trap: Towards Matter-Wave Interferometry with Massive Objects
Quantum mechanics (QM) and General relativity (GR), also known as the theory of gravity, are the two pillars of modern physics. A matter-wave interferometer with a massive particle, can test numerous fundamental ideas, including the spatial superposition principle - a foundational concept in QM - in completely new regimes, as well as the interface between QM and GR, e.g., testing the quantization of gravity. Consequently, there exists an intensive effort to realize such an interferometer. While…

Ringdown mode amplitudes of charged binary black holes
Zexin Hu, Daniela D. Doneva, Ziming Wang, Vasileios Paschalidis, Gabriele Bozzola, Stoytcho S. Yazadjiev, Lijing Shao
https://arxiv.org/abs/2509.07111

Ringdown mode amplitudes of charged binary black holes
The ringdown phase of the binary black hole (BBH) merger provides a clean and direct probe of strong-field gravity and tests of the nature of black holes. The quasinormal mode (QNM) frequencies in modified gravity theories, as well as their amplitudes and phases, might deviate from the Kerr ones in general relativity. Charged black holes (BHs) in Einstein-Maxwell theory provide an excellent example of a beyond-Kerr solution with direct astrophysical and fundamental physics applications. In this…

Near-Extremal Black Holes in Modified Gravity via Spectral Methods
Kelvin Ka-Ho Lam, Adrian Ka-Wai Chung, Nicol\'as Yunes
https://arxiv.org/abs/2509.07061 https://

Near-Extremal Black Holes in Modified Gravity via Spectral Methods
Rapidly-rotating black-hole spacetimes outside general relativity are key to many tests of Einstein's theory. We here develop an efficient spectral method to represent such spacetimes analytically, in closed-form, and to high accuracy, in a large class of effective-field-theory extensions of general relativity. We exemplify this method by constructing, for the first time, closed-form and analytic representations of spinning black holes in scalar-Gauss-Bonnet, dynamical Chern-Simons, and axidila…

Tracing Signatures of Modified Gravity in Redshift-Space Galaxy Bispectrum Multipoles: Prospects for Euclid
Sourav Pal, Debanjan Sarkar
https://arxiv.org/abs/2508.19106 https://…

Tracing Signatures of Modified Gravity in Redshift-Space Galaxy Bispectrum Multipoles: Prospects for Euclid
We study the galaxy bispectrum multipoles in the Hu-Sawicki $f(R)$ gravity model, where a scalar degree of freedom mediates a fifth force that is screened in high-density environments. The model is specified by $f_{R0}$, the present-day background value of the scalar field, which controls the strength of deviations from General Relativity (GR). Using perturbation theory, we compute the redshift-space galaxy bispectrum with the full scale- and time-dependent second-order kernels, incorporating c…

A Parametrized Test of General Relativity for LISA Massive Black Hole Binary Inspirals
Manuel Piarulli, Sylvain Marsat, Elise M. S\"anger, Alessandra Buonanno, Jan Steinhoff, Nicola Tamanini
https://arxiv.org/abs/2510.06330

A Parametrized Test of General Relativity for LISA Massive Black Hole Binary Inspirals
Laser Interferometer Space Antenna (LISA) observations of massive black hole binaries (MBHBs) will provide long duration inspiral signals with high signal-to-noise ratio (SNR) data, ideal for testing general relativity (GR) in the strong-field and high-velocity regime. We present an extension of the Flexible Theory-Independent (FTI) framework, adapted to gravitational waves (GWs) from MBHBs observed with LISA, to perform parametrized inspiral tests of GR. This approach introduces generic deviat…

Parametric feedback cooling of librations of a nanodiamond in a Paul trap: Towards matter-wave interferometry with massive objects
Maria Muretova, Yonathan Japha, Marko Toros, Ron Folman
https://arxiv.org/abs/2508.13723

Parametric feedback cooling of librations of a nanodiamond in a Paul trap: Towards matter-wave interferometry with massive objects
Quantum mechanics (QM) and General relativity (GR), also known as the theory of gravity, are the two pillars of modern physics. A matter-wave interferometer with a massive particle can test numerous fundamental ideas, including the spatial superposition principle - a foundational concept in QM - in completely new regimes, as well as the interface between QM and GR, e.g., testing the quantization of gravity. Consequently, there exists an intensive effort to realize such an interferometer. While …

Thermal description of braneworld effective theories
Soham Bhattacharyya, Soumitra SenGupta
https://arxiv.org/abs/2508.14228 https://arxiv.org/pdf/2508.142…

Thermal description of braneworld effective theories
Low-energy effective theories provide the natural description of four-dimensional physics in higher-dimensional geometries, where the imprint of the bulk appears as parameters of the lower dimensional theory. Motivated by the recent progress in the first-order thermodynamic formulation of modified gravity theories, we investigate the thermodynamics of effective theories in braneworld scenarios and thereby the attractor mechanism towards general relativity in such theories. We consider the two-b…

Quantum control of Nitrogen-Vacancy spin in Diamonds: Towards matter-wave interferometry with massive objects
N. Levi, O. Feldman, Y. Rosenzweig, D. Groswasser, A. Elgarat, M. Gal-Katizri, R. Folman
https://arxiv.org/abs/2508.15504

Quantum control of Nitrogen-Vacancy spin in Diamonds: Towards matter-wave interferometry with massive objects
Quantum mechanics (QM) and General relativity (GR), also known as the theory of gravity, are the two pillars of modern physics. A matter-wave interferometer with a massive particle can test numerous fundamental ideas, including the spatial superposition principle - a foundational concept in QM - in previously unexplored regimes. It also opens the possibility of probing the interface between QM and GR, such as testing the quantization of gravity. Consequently, there exists an intensive effort to…

Simulating Binary Neutron Star Mergers with Finite-temperature Equations of State: The influences of the slope of the symmetry energy and artificial heating
Henrique Gieg, Maximiliano Ujevic, Armen Sedrakian, Tim Dietrich
https://arxiv.org/abs/2507.23684

Simulating Binary Neutron Star Mergers with Finite-temperature Equations of State: The influences of the slope of the symmetry energy and artificial heating
We present a new set of numerical-relativity simulations of merging binary neutron stars, aiming to identify possible observable signatures of the slope of the symmetry energy $L_{\rm sym}$. To achieve this goal, we employ a set of equations of state based on a parameterization of the covariant density functional theory of nuclear matter that allows controlled variations of $L_{\rm sym}$ and the skewness $Q_{\rm sat}$, holding the latter fixed. For a set of our simulations, we identify a steep …

Covariant and Gauge-invariant Metric-based Gravitational-waves Extraction in Numerical Relativity
Joan Fontbut\'e, Sebastiano Bernuzzi, Simone Albanesi, David Radice, Alireza Rashti, William Cook, Boris Daszuta, Alessandro Nagar
https://arxiv.org/abs/2508.03799

Covariant and Gauge-invariant Metric-based Gravitational-waves Extraction in Numerical Relativity
We revisit the problem of gravitational-wave extraction in numerical relativity with gauge-invariant metric perturbation theory of spherical spacetimes. Our extraction algorithm allows the computation of even-parity (Zerilli-Moncrief) and odd-parity (Regge-Wheeler) multipoles of the strain from a (3+1) metric without the assumption that the spherical background is in Schwarzschild coordinates. The algorithm is validated with a comprehensive suite of 3D problems including fluid ($f$-modes) and s…

A Theory of the Big Bang in McTaggart's Time
Paul Merriam
https://arxiv.org/abs/2508.15863 https://arxiv.org/pdf/2508.15863

A Theory of the Big Bang in McTaggart's Time
There are long standing questions about the Big Bang What were its properties? Was there nothing before it? Was the universe always here? Many conceptual issues revolve around time. This paper gives a novel model based on McTaggarts temporal distinction between the A-series future-present-past and B-series earlier-times to later times. These series are useful while situated in a Presentist and Fragmentalist account of quantum mechanics, one in which the consistency with the Special Relativity i…

Affine Gauge Theory: A Diffeomorphism Invariant Gauge Theory of Gravity
Kurniawan Tjandra, Kuldip Singh
https://arxiv.org/abs/2509.26410 https://arxiv.org/…

Affine Gauge Theory: A Diffeomorphism Invariant Gauge Theory of Gravity
This paper is a comprehensive investigation of the Affine Gauge Theory (AGT) as a gauge theory of gravity having the same mathematical structure as gauge theories of the other fundamental forces of nature. This mathematical structure consists of a principal fiber bundle over the spacetime manifold that is endowed with an affine connection. The relationship between AGT and various formulations of teleparallel theories of gravity, which are alternatives to General Relativity, are examined. Here, …

Trapping and cooling of nanodiamonds in a Paul trap under ultra-high vacuum: Towards matter-wave interferometry with massive objects
Omer Feldman, Ben Baruch Shultz, Maria Muretova, Or Dobkowski, Yonathan Japha, David Grosswasser, Ron Folman
https://arxiv.org/abs/2508.14687

Trapping and cooling of nanodiamonds in a Paul trap under ultra-high vacuum: Towards matter-wave interferometry with massive objects
Quantum mechanics (QM) and General relativity (GR), also known as the theory of gravity, are the two pillars of modern physics. A matter-wave interferometer with a massive particle can test numerous fundamental ideas, including the spatial superposition principle - a foundational concept in QM - in previously unexplored regimes. It also opens the possibility of probing the interface between QM and GR, such as testing the quantization of gravity. Consequently, there exists an intensive effort to…

Analytic and accurate approximate metrics for black holes with arbitrary rotation in beyond-Einstein gravity using spectral methods
Kelvin Ka-Ho Lam, Adrian Ka-Wai Chung, Nicol\'as Yunes
https://arxiv.org/abs/2510.05208

Analytic and accurate approximate metrics for black holes with arbitrary rotation in beyond-Einstein gravity using spectral methods
A key obstacle for theory-specific tests of general relativity is the lack of accurate black-hole solutions in beyond-Einstein theories, especially for moderate to high spins. We address this by developing a general framework--based on spectral and pseudospectral methods--to obtain analytic, closed-form spacetimes representing stationary, axisymmetric black holes in effective-field-theory extensions of general relativity to leading order in the coupling constants. The approach models the spacet…

Fabrication of nano-diamonds with a single NV center: Towards matter-wave interferometry with massive objects
Menachem Givon, Yaniv Bar-Haim, David Groswasser, Asi Solodar, Nadav Aharon, Michael Belman, Amit Yosefi, Erez Golan, Jurgen Jopp, Ron Folman
https://arxiv.org/abs/2508.13662

Fabrication of nano-diamonds with a single NV center: Towards matter-wave interferometry with massive objects
Quantum mechanics (QM) and General relativity (GR), also known as the theory of gravity, are the two pillars of modern physics. A matter-wave interferometer with a massive particle can test numerous fundamental ideas, including the spatial superposition principle - a foundational concept in QM - in previously unexplored regimes. It also opens the possibility of probing the interface between QM and GR, such as testing the quantization of gravity. Consequently, there exists an intensive effort to…

Spin versus Magic: Lessons from Gluon and Graviton Scattering
John Gargalionis, Nathan Moynihan, Sokratis Trifinopoulos, Ewan N. V. Wallace, Chris D. White, Martin J. White
https://arxiv.org/abs/2508.14967

Spin versus Magic: Lessons from Gluon and Graviton Scattering
The quantum property of non-stabiliserness, also known as magic, plays a key role in designing quantum computing systems. How to produce, manipulate and enhance magic remains mysterious, such that concrete examples of physical systems that manifest magic behaviour are sought after. In this paper, we study two-particle scattering of gluons and gravitons in Yang--Mills theory and General Relativity, as well as their supersymmetric extensions. This provides an interesting case of two-qubit systems…

Wormholes in Einstein-Dirac-Maxwell theory with identical spacetime asymptotics
Vladimir Dzhunushaliev, Vladimir Folomeev, Nurzada Beissen, Adilet Nurmukhamedov
https://arxiv.org/abs/2510.03656

Wormholes in Einstein-Dirac-Maxwell theory with identical spacetime asymptotics
Within general relativity, we study spherically symmetric configurations with wormhole topology consisting of spinor fields and a Maxwell electric field. For such a system, we construct complete families of regular asymmetric solutions describing wormholes connecting two identical Minkowski spacetimes. The physical properties of such systems are completely determined by the values of three input quantities: the throat parameter, the spinor frequency, and the coupling constant. Depending on the …

Neutralization of Levitated Charged Nanodiamond: Towards matter-wave interferometry with massive objects
Sela Liran, Or Dobkowski, Rafael Benjaminov, Peter Skakunenko, Michael Averbukh, Yaniv Bar-Haim, David Groswasser, Joshua H. Baraban, Ron Folman
https://arxiv.org/abs/2508.15625

Neutralization of Levitated Charged Nanodiamond: Towards matter-wave interferometry with massive objects
Quantum mechanics (QM) and General relativity (GR), also known as the theory of gravity, are the two pillars of modern physics. A matter-wave interferometer with a massive particle, can test numerous fundamental ideas, including the spatial superposition principle - a foundational concept in QM - in completely new regimes, as well as the interface between QM and GR, e.g., testing the quantization of gravity. Consequently, there exists an intensive effort to realize such an interferometer. While…

Kullback-Leibler Divergence as a Measure of Irreversible Information Loss Near Black Hole Horizons
Tatsuaki Tsuruyama
https://arxiv.org/abs/2508.04348 https://

Kullback-Leibler Divergence as a Measure of Irreversible Information Loss Near Black Hole Horizons
We present a unified theoretical framework that integrates information theory, thermodynamics, and general relativity to analyze the fundamental limit of decoding time-encoded signals in curved spacetime. In particular, we introduce the Kullback-Leibler divergence (KLD) as a quantitative measure of the mismatch between the transmitted and received symbol distributions induced by gravitational time dilation. Using a minimal communication model, we derive the critical radius at which information …

Strong Confinement of a Nanoparticle in a Needle Paul Trap: Towards Matter-Wave Interferometry with Nanodiamonds
Peter Skakunenko, Daniel Folman, Yaniv Bar-Haim, Ron Folman
https://arxiv.org/abs/2508.14272

Strong Confinement of a Nanoparticle in a Needle Paul Trap: Towards Matter-Wave Interferometry with Nanodiamonds
Quantum mechanics (QM) and General relativity (GR), also known as the theory of gravity, are the two pillars of modern physics. A matter-wave interferometer with a massive particle, can test numerous fundamental ideas, including the spatial superposition principle - a foundational concept in QM - in completely new regimes, as well as the interface between QM and GR, e.g., testing the quantization of gravity. Consequently, there exists an intensive effort to realize such an interferometer. While…

Consequences of Undecidability in Physics on the Theory of Everything
Mir Faizal, Lawrence M. Krauss, Arshid Shabir, Francesco Marino
https://arxiv.org/abs/2507.22950 https://…

Consequences of Undecidability in Physics on the Theory of Everything
General relativity treats spacetime as dynamical and exhibits its breakdown at singularities. This failure is interpreted as evidence that quantum gravity is not a theory formulated within spacetime; instead, it must explain the very emergence of spacetime from deeper quantum degrees of freedom, thereby resolving singularities. Quantum gravity is therefore envisaged as an axiomatic structure, and algorithmic calculations acting on these axioms are expected to generate spacetime. However, Gödel…

The double copy as a doppelg\"{a}nger
Nathan Moynihan, Michael L. Reichenberg Ashby, Chris D. White
https://arxiv.org/abs/2509.22350 https://arxiv.org…

The double copy as a doppelgänger
The double copy relates scattering amplitudes and classical solutions in non-abelian gauge theories and gravity. As such, it is usually expressed in the conventional second-order formalisms in both theories corresponding to standard Yang-Mills theory, and the Einstein--Hilbert action in General Relativity. In this paper, we instead consider alternative formulations of gravity, which are known to terminate at finite order in the coupling at Lagrangian level. We focus in particular on the Chern--…

Dirac, Schroedinger, and Maxwell equations in scalar and vector field quantum mechanics
Boris Chichkov
https://arxiv.org/abs/2508.14583 https://arxiv.org/p…

Dirac, Schroedinger, and Maxwell equations in scalar and vector field quantum mechanics
The quantum theory of relativistic particles, based on the first quantization technique similar to that used by Schroedinger and Dirac in formulating quantum mechanics, is reconsidered on the basis of a photon-like dispersion relation corresponding to the energy conservation equation of Einstein's special relativity. First, scalar quantum mechanics of particles operating with their wave functions is discussed. Using the first quantization of the photon-like dispersion relation, very simple new …

On the viability of minimal Ho\v{r}ava gravity
Ted Jacobson, Pranav Pulakkat
https://arxiv.org/abs/2508.03106 https://arxiv.org/pdf/2508.03106

On the viability of minimal Hořava gravity
Hořava gravity is a Lorentz-violating modification of general relativity (GR) with a preferred spacelike foliation. Observational evidence has put strong constraints on the parameter values in this model, so that the remaining viable sector is well-characterized by the Newton constant and a single additional parameter. We analyze this restricted theory, which is called minimal Hořava gravity ($\mathrm{mHg}$), from the Hamiltonian point of view. We find that in order to eliminate a pathologica…

Post-Carrollian Mechanics, Ideal Gas, and Gravity
Mojtaba Najafizadeh
https://arxiv.org/abs/2509.14330 https://arxiv.org/pdf/2509.14330

Post-Carrollian Mechanics, Ideal Gas, and Gravity
Energy and momentum in Newtonian mechanics have the familiar relations, ($\mathrm{E}=mv^2/2$) and ($\mathbf{P}=m\mathbf{v}$), derived from the non-relativistic limit of special relativity. In this study, we find the corresponding relations to formulate the so-called ``post-Carrollian mechanics'' by applying the ultra-relativistic limit to tachyon theory, resulting in ($\mathrm{E}={m\,c^{\,3}}/{v}$) and ($\mathbf{P}=\mathbf{\hat{v}}\,{m\,c^{\,3}}/{2\,v^{\,2}}$). Using these, we determine the ene…

Consistency of spin effects between numerical relativity and perturbation theory for inspiraling comparable-mass black hole binaries
Tousif Islam, Gaurav Khanna, Scott E. Field
https://arxiv.org/abs/2510.00531

Consistency of spin effects between numerical relativity and perturbation theory for inspiraling comparable-mass black hole binaries
Numerical relativity (NR) provides the most accurate waveforms for comparable-mass binary black holes but becomes prohibitively expensive for increasingly asymmetric mass ratios. Point-particle black hole perturbation theory (ppBHPT), which expands the Einstein equations in the small-mass-ratio limit, offers a computationally efficient alternative but is expected to break down in the comparable-mass regime because it neglects nonlinear effects. Nonetheless, several recent studies have shown tha…

Dynamical Love numbers of black holes: theory and gravitational waveforms
Sumanta Chakraborty, Valerio De Luca, Leonardo Gualtieri, Paolo Pani
https://arxiv.org/abs/2507.22994 h…

Dynamical Love numbers of black holes: theory and gravitational waveforms
In General Relativity, the static tidal Love numbers of black holes vanish identically. Whether this remains true for time-dependent tidal fields -- i.e., in the case of dynamical tidal Love numbers -- is an open question, complicated by subtle issues in the definition and computation of the tidal response at finite frequency. In this work, we compute the dynamical tidal perturbations of a Schwarzschild black hole to quadratic order in the tidal frequency. By employing the Teukolsky formalism i…

Lunar Reference Timescale
Adrien Bourgoin (LTE, Observatoire de Paris, Universit\'e PSL, CNRS, Sorbonne Universit\'e, LNE, Paris, France), Pascale Defraigne (Royal Observatory of Belgium, Brussels, Belgium), Fr\'ed\'eric Meynadier (Time Department, BIPM, Pavillon de Breteuil, S\`evres, France)
https://arxiv.org/abs/2507.215…

Lunar Reference Timescale
Setting up a relativistic lunar reference frame is of a prime importance in the context of future exploration missions to the Moon. If the procedure for building a consistent reference frame within the framework of the general theory of relativity is well established (cf. resolutions B.3 of IAU 2000), there is still some freedom in the choice of the coordinate timescale to be adopted as reference in the cislunar region. In this paper, we review the orders of magnitude of the relativistic effect…

Loop Quantum Vector-Tensor Gravity and Its Spherically Symmetric Model
Shengzhi Li, Yongge Ma
https://arxiv.org/abs/2509.02056 https://arxiv.org/pdf/2509.0…

Loop Quantum Vector-Tensor Gravity and Its Spherically Symmetric Model
The Hamiltoinian analysis of the vector-tensor theory of gravity is performed. The resulting geometrical dynamics is reformulated into the connection dynamics, with the real SU(2)-connection serving as one of the configuration variables. This formulation allows us to extend the loop quantization scheme of general relativity to the vector-tensor theory, thereby rigorously constructing its quantum kinematical framework. The scalar constraint is promoted to a well-defined operator in the vertex Hi…

Prospect on constraining string-theory-inspired model from gravitational redshift measurements
Li Hu, Rong-Gen Cai, Song He, Li-Fang Li, Tong Liu, Peng Xu, Shao-Jiang Wang
https://arxiv.org/abs/2509.24622

Prospect on constraining string-theory-inspired model from gravitational redshift measurements
Scalar-tensor gravity represents a natural extension of general relativity. Testing such models experimentally provides a crucial pathway to probing physics at high-energy scales, particularly in the context of string theory. This paper investigates a string-theory-inspired scalar-tensor gravity -- the dilaton model -- and identifies regions of its parameter space potentially constrained by gravitational redshift experiments in future. By further modeling the mass distribution in low-density en…

Yukawa-Casimir wormholes within Einstein-Cartan gravity framework
Nayan Sarkar, Susmita Sarkar, Abdelmalek Bouzenada
https://arxiv.org/abs/2509.02631 https://

Yukawa-Casimir wormholes within Einstein-Cartan gravity framework
The Einstein-Cartan (EC) theory of gravity provides a natural extension of general relativity by incorporating spacetime torsion to account for the intrinsic spin of matter. In this work, we investigate Yukawa-Casimir traversable wormholes supported by three distinct Yukawa-Casimir energy density profiles within the framework of EC gravity. The resulting shape functions are shown to satisfy all the fundamental requirements for traversable wormhole geometries. Our analysis reveals that the prese…

Toward a Theory of Gravitational Wave Turbulence
Holly Krynicki, Jiaxi Wu, Elias R. Most
https://arxiv.org/abs/2509.19769 https://arxiv.org/pdf/2509.19769

Toward a Theory of Gravitational Wave Turbulence
General relativity describes the dynamics of gravitational waves, which can feature nonlinear interactions, such as those underlying turbulent processes. Theoretical and numerical explorations have demonstrated the existence of gravitational wave turbulence, of which a full and general mathematical description is currently not known. Here, we take essential steps towards such a theory. Leveraging a formulation exactly recasting general relativity as a set of nonlinear electrodynamics equations,…

Schwarzschild Spacetime and the Local Limit of Nonlocal Gravity
Yahya Mohammadi, Javad Tabatabaei, Shant Baghram, Bahram Mashhoon
https://arxiv.org/abs/2509.20089 https://

Schwarzschild Spacetime and the Local Limit of Nonlocal Gravity
We investigate static spherically symmetric solutions within the framework of the local limit of nonlocal gravity. This theory departs from Einstein's general relativity (GR) through the introduction of a scalar gravitational susceptibility function $S(x)$, $1+S > 0$, which is a new feature of the spacetime that vanishes in the GR limit. It is shown that the Schwarzschild spacetime constitutes an exact solution of the modified source-free gravitational field equations provided $S$ is a constant…

Quantum Gravity and Inflation as an Open System: A New Paradigm
Alan Sebasti\'an Morales, Mauricio Bellini, Juan Ignacio Musmarra
https://arxiv.org/abs/2509.19507 https://…

Quantum Gravity and Inflation as an Open System: A New Paradigm
As part of our program to develop a general theory of relativity for open systems, we introduce a covariant theory that incorporates the effects of classical and quantum spacetime alterations in a new metric tensor that effectively includes these alterations, thereby generating a Riemannian manifold from a new varied action without boundary terms. We illustrate the theory by studying an inflationary model which incorporates the quantum feedback effects of spacetime on the dynamics of the inflat…

Teleparallel gravity from the principal bundle viewpoint
Sebastian Brezina, Eugenia Boffo, Martin Kr\v{s}\v{s}\'ak
https://arxiv.org/abs/2507.23672 https://

Teleparallel gravity from the principal bundle viewpoint
We examine whether the Teleparallel Equivalent of General Relativity (TEGR) can be formulated as a gauge theory in the language of connections on principal bundles. We argue in favor of using either the affine bundle with the Poincaré group or, equivalently, the orthonormal frame bundle with the Lorentz group as the structure group. Following the framework of Trautman--where gauge symmetries are determined using the absolute elements--we set to identify the absolute elements and gauge symmetri…

Probing missing physics from inspiralling compact binaries via time-frequency tracks
Debtroy Das, Soumen Roy, Anand S. Sengupta, Cosimo Bambi
https://arxiv.org/abs/2507.21566 ht…

Probing missing physics from inspiralling compact binaries via time-frequency tracks
The orbital evolution of binary black hole (BBH) systems is determined by the component masses and spins of the black holes and the governing gravity theory. Gravitational wave (GW) signals from the evolution of BBH orbits offer an unparalleled opportunity for examining the predictions of General Relativity (GR) and for searching for missing physics in the current waveform models. We present a method of stacking up the time-frequency pixel energies through the orbital frequency evolution with t…

Doubly regular black holes
Arthur G. Suvorov, Pedro Bargue\~no
https://arxiv.org/abs/2507.23250 https://arxiv.org/pdf/2507.23250

Doubly regular black holes
In addition to curvature singularities, electrovacuum black holes in general relativity exhibit thermodynamic singularities. These so-called Davies' points occur at non-extremal values of charge and spin where the heat capacity diverges and may indicate a type of theoretical incompleteness. The thermodynamic regularity of several families of static, asymptotically-flat spacetimes with bounded curvature invariants is examined using a theory-agnostic framework, showing that while they may be regu…

Generic EFT-motivated beyond General Relativity gravitational wave tests and their curvature dependence: from observation to interpretation
Laura Bernard, Suvendu Giri, Luis Lehner, Riccardo Sturani
https://arxiv.org/abs/2507.17143

Generic EFT-motivated beyond General Relativity gravitational wave tests and their curvature dependence: from observation to interpretation
We present a "dictionary" to expedite the identification of potential deviations in gravitational waveforms from those predicted by General Relativity (GR) during the inspiral phase of black hole binaries. Assuming deviations from GR can be described by a local Effective Field Theory (EFT) formulated in terms of curvature operators (and possibly additional scalar fields), this dictionary characterizes how deviations scale with the masses of the binary components and identifies the leading order…

Relativistic second gradient theory of continuous media
Mina Chapon (LMPS), Lionel Darondeau (IMJ-PRG), Rodrigue Desmorat (LMT, LMPS), Cl\'ement Ecker (LMPS), Boris Kolev (LMPS)
https://arxiv.org/abs/2507.13030

Relativistic second gradient theory of continuous media
Variational Relativity is a framework developed by Souriau in the sixties to better formulate General Relativity and its classical limit\,: Classical Continuum Mechanics. It has been used, for instance, to formulate Hyperelasticity in General Relativity. In that case, two primary variables are involved, the universe (Lorentzian) metric $g$ and the matter field $Ψ$. A Lagrangian density depending on the 1-jet of these variables is then introduced which must satisfy the principle of General Cova…

Functional inference on deviations from General Relativity
Costantino Pacilio, Riccardo Buscicchio
https://arxiv.org/abs/2507.13454 https://

Functional inference on deviations from General Relativity
Extensions of general relativity often predict modifications to gravitational waveform morphology that depend functionally on source parameters, such as the masses and spins of coalescing black holes. However, current analyses of strong-field gravity lack robust, data-driven methods to infer such functional dependencies. In this work, we introduce GRANITA, a non-perturbative, theory-agnostic framework to characterize parameter-dependent deviations from general relativity using Gaussian process …

An Introduction to Gravitational Wave Theory
Simone Speziale, Dani\`ele A. Steer
https://arxiv.org/abs/2508.21817 https://arxiv.org/pdf/2508.21817

An Introduction to Gravitational Wave Theory
Introduction to the theoretical foundations of gravitational waves: from general relativity to detection and binary system waveforms. Lecture notes prepared for the MaNiTou summer school on gravitational waves. Draft chapter for the CNRS contemporary Encyclopaedia Sciences to be published by ISTE.

The fundamental physical importance of generic off-diagonal solutions and Grigori Perelman entropy in the Einstein gravity theory
Sergiu I. Vacaru, El\c{s}en V. Veliev
https://arxiv.org/abs/2508.10939 …

The fundamental physical importance of generic off-diagonal solutions and Grigori Perelman entropy in the Einstein gravity theory
The gravitational field equations in general relativity (GR) consist of a sophisticated system of nonlinear partial differential equations. Solving such equations in some generic off-diagonal forms is usually a hard analytic or numeric task. Physically important solutions in GR were constructed using a diagonal ansatz for metrics with a maximum of 4 independent coefficients. The Einstein equations can be solved in exact or parametric forms determined by some integration constants for correspond…

Dynamical theory for spherical black holes in modified gravity
Asier Alonso-Bardaji, David Brizuela
https://arxiv.org/abs/2507.19380 https://arxiv.org/pdf/…

Dynamical theory for spherical black holes in modified gravity
We provide a general algorithm to construct a Hamiltonian, such that its dynamical flow covariantly defines any given spherically symmetric and static metric. This Hamiltonian is defined as a linear combination of the standard (general relativistic) radial diffeomorphism constraint plus a Hamiltonian constraint that is appropriately deformed as compared to its corresponding form in general relativity though it does not include higher-derivative terms. Therefore, given a static model of spherica…

General form of $f(R)$ and $(2 1)$-dimensional charge/non-charge black hole solutions
G. G. L. Nashed
https://arxiv.org/abs/2509.15282 https://arxiv.org/pd…

General form of $f(R)$ and $(2+1)$-dimensional charge/non-charge black hole solutions
We introduce novel black hole (BH) solutions, charge/non-charge, within the framework of $f(R)$ gravity, a theory that does not inherently include a cosmological constant, using equal/diffirent metric ansatzs. Remarkably, these solutions exhibit asymptotically Anti-de Sitter (AdS) or de Sitter (dS) behavior, depending on their parameter values. Unlike the BTZ solutions of General Relativity, which feature a causal singularity and constant scalar invariants, our solutions display strong spacetim…

Master field equations for spherically symmetric gravitational fields beyond general relativity
Ra\'ul Carballo-Rubio
https://arxiv.org/abs/2507.15920 …

Master field equations for spherically symmetric gravitational fields beyond general relativity
I construct a set of master field equations encompassing all possible second-order field equations for spherically symmetric spacetimes beyond general relativity. The structure of 2-dimensional Horndeski theory is leveraged to define a spherically symmetric gravitational tensor that is identically conserved and can play an equivalent role as the Einstein tensor in the coupling to spherically symmetric stress-energy tensors. The master field equations provide a framework in which to study a wide…

Emergent field theory
Erick I. Duque
https://arxiv.org/abs/2507.16163 https://arxiv.org/pdf/2507.16163…

Emergent field theory
The uniqueness theorems for general relativity and Yang-Mills theories can be circumvented by dropping the ubiquitous, yet often implicit, assumption that physical fields, such as the spacetime metric, are fundamental. The novel concept of emergent fields makes it possible to construct modified theories of gravity and forces where the spacetime metric and strength tensor fields emerge from a covariance analysis in the canonical formulation with nontrivial relations to the fundamental phase spac…

Gravitational waveforms from inspiraling compact binaries in quadratic gravity and their parameterized post-Einstein characterization
Matheus F. S. Alves, L. G. Medeiros, Davi C. Rodrigues
https://arxiv.org/abs/2507.15571

Gravitational waveforms from inspiraling compact binaries in quadratic gravity and their parameterized post-Einstein characterization
We investigate gravitational waveforms from the inspiral phase of compact binary systems within the framework of quadratic gravity and map their deviations from general relativity into the parameterized post-Einstein (PPE) formalism to constrain the theory parameters. Quadratic gravity generically includes a massive spin-2 ghost, which leads to ill-defined energy and angular momentum fluxes. Following earlier proposals, we remove these unphysical features by imposing a constraint on the massive…

Replaced article(s) found for gr-qc. https://arxiv.org/list/gr-qc/new
[2/2]:
- Holomorphic Unified Field Theory of Gravity and the Standard Model
John. W. Moffat, Ethan. J. Thompson