Tootfinder

Conservation Laws and Boundedness for Linearised Einstein--Maxwell Equations on the Reissner--Nordstr\"om Black Hole
Marios A. Apetroaie, Sam C. Collingbourne, Elena Giorgi
https://arxiv.org/abs/2506.04812

Conservation Laws and Boundedness for Linearised Einstein--Maxwell Equations on the Reissner--Nordström Black Hole
We study the linearised Einstein--Maxwell equations on the Reissner--Nordström spacetime and derive the canonical energy conservation law in double null gauge. In the spirit of the work of Holzegel and the second author, we avoid any use of the hyperbolic nature of the Teukolsky equations and rely solely on the conservation law to establish control of energy fluxes for the gauge-invariant Teukolsky variables, previously identified by the third author, along all outgoing null hypersurfaces, for…

Nobel Prize Laureate Kip Thorne speaking yesterday at the Albert Einstein Institute in Postdam, Germany:
"Donald Trump is destroying America's capacity for [leading science].
We are counting on Europe to take over here and elsewhere." ⚛️
https://bsky.app/profile/abazajian.n…

Kev Abazajian (@abazajian.net)
Nobel Prize Laureate Kip Thorne speaking yesterday at the Albert Einstein Institute in Postdam, Germany: "Donald Trump is destroying America's capacity for [leading science]. We are counting on Europe to take over here and elsewhere." ⚛️ 🧪

This https://arxiv.org/abs/2502.12687 has been replaced.
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Black Hole Chemistry Knows Extra Dimensions
: In this note, we study an extra dimension effect on the black hole chemistry in the 8-dimensional Einstein-Yang-Mills-Maxwell theory. The base spacetime contains 4- dimensional compact manifolds and an instanton on top of those. We demonstrate how the extra dimensions affect the phase transition and viable black hole sizes in the 4-dimensional Einstein frame through the black hole chemistry. We focus on asymptotically anti-de Sitter spacetimes for the effective 4-dimensional model obtained by…

This https://arxiv.org/abs/2505.24502 has been replaced.
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Predictability of quantum observables: Applications in QKD and top quarks
We quantify and optimize the predictability of local observables in bipartite quantum systems by employing the Bayes risk and the inference variance, two measures rooted in statistical learning theory. Specifically, we minimized these quantities when the prediction is improved by an additional quantum system, providing analytical expressions for arbitrary two-qubit states, and showcasing a connection with Einstein-Podolsky-Rosen steering criteria. Then, we embed our Bayes risk minimization into…

Stable supersolids and boselets in spin-orbit-coupled Bose-Einstein condensates with three-body interactions
Rajamanickam Ravisankar, Sanu Kumar Gangwar, Henrique Fabrelli, Yongping Zhang, Paulsamy Muruganandam, Pankaj Kumar Mishra, Emmanuel Kengne, Gao Xianlong, Boris A. Malomed
https://arxiv.org/abs/2506.03505

Stable supersolids and boselets in spin-orbit-coupled Bose-Einstein condensates with three-body interactions
We explore the stability of supersolid striped waves, plane-wave boselets, and other extended states in one-dimensional spin-orbit-coupled Bose-Einstein condensates with repulsive three-body interactions (R3BIs), modeled by quintic terms in the framework of the corresponding Gross-Pitaevskii equations. In the absence of R3BIs, the extended states are susceptible to the modulational instability (MI) induced by the cubic attractive nonlinearity. Using the linearized Bogoliubov-de-Gennes equations…

Three-pion Bose-Einstein correlations measured in proton-proton collisions
LHCb collaboration
https://arxiv.org/abs/2506.03072 https://

Three-pion Bose-Einstein correlations measured in proton-proton collisions
A study on the Bose-Einstein correlations for triplets of same-sign pions is presented. The analysis is performed using proton-proton collisions at a centre-of-mass energy of $\sqrt{s}$ = 7 TeV, recorded by the LHCb experiment, corresponding to an integrated luminosity of 1.0 fb$^{-1}$. For the first time, the results are interpreted in the core-halo model. The parameters of the model are determined in regions of charged-particle multiplicity. This measurement provides insight into the nature o…

Viscosity in Isotropic Cosmological Backgrounds in General Relativity and Starobinsky Gravity
Eliseo Pavone, Luigi Tedesco
https://arxiv.org/abs/2506.05180

Viscosity in Isotropic Cosmological Backgrounds in General Relativity and Starobinsky Gravity
We present a general analysis of the role of shear viscosity in cosmological backgrounds, focusing on isotropic space-time in both Einstein and $f(R)$ gravity. By computing the divergence of the stress-energy tensor in a general class of isotropic (but not necessarily homogeneous) geometries, we show that shear viscosity does not contribute to the background dynamics when the fluid is comoving. This result holds in both the Jordan and Einstein frames, and implies that shear viscosity cannot aff…

Prospects for the Detection of High-Redshift Gamma-Ray Bursts in the Era of EP and SVOM
Jun-Jie Wei, Xue-Feng Wu
https://arxiv.org/abs/2506.04709 https://

Prospects for the Detection of High-Redshift Gamma-Ray Bursts in the Era of EP and SVOM
Gamma-ray bursts (GRBs) are a promising probe of the high-redshift Universe, but their detection remains observationally challenging. In this work, we explore the detectability of high-$z$ GRBs by the Wide-field X-ray Telescope (WXT) aboard the Einstein Probe (\emph{EP}) and the coded-mask gamma-ray imager (ECLAIRs) aboard the Space-based multi-band astronomical Variable Objects Monitor (\emph{SVOM}). Using a population synthesis model calibrated to $Swift$ GRB observations, we develop a tool t…

On a linear equation arising in the study of phase separation of BEC's
Christos Sourdis
https://arxiv.org/abs/2506.05299 https://…

On a linear equation arising in the study of phase separation of BEC's
We consider the inner limit system describing the phase separation in two-component Bose-Einstein condensates linearized around the one-dimensional solution in an infinite strip with zero and periodic boundary conditions, and obtain optimal invertibility estimates for the Fourier modes without necessarily assuming orthogonality conditions.

Testing gravity with wide binaries -- 3D velocities and distances of wide binaries from Gaia and HARPS
R. Saglia, L. Pasquini, F. Patat, H. -G. Ludwig, R. Giribaldi, I. Leao, J. R. de Medeiros, Michael T. Murphy
https://arxiv.org/abs/2506.05049

Testing gravity with wide binaries -- 3D velocities and distances of wide binaries from Gaia and HARPS
Wide Binaries (WBs) are interesting systems to test Newton-Einstein gravity in low potentials. The basic concept is to verify whether the difference in velocity between the WB components is compatible with what is expected from the Newton law. Previous attempts, based solely on Gaia proper motion differences scaled to transverse velocity differences using mean parallax distances, do not provide conclusive results. Here we add to the Gaia transverse velocities precise measurements of the third v…

Bose-Einstein Condensation, Fluctuations and Spontaneous Symmetry Breaking
A. Crisanti, A. Sarracino, M. Zannetti
https://arxiv.org/abs/2505.24228 https://…

Bose-Einstein Condensation, Fluctuations and Spontaneous Symmetry Breaking
The realisation of Bose-Einstein condensation under grand-canonical conditions has provided the experimental evidence for the simultaneous occurrence of macroscopic fluctuations and phase coherence of the condensate. The observation of these two features, against a consolidated tradition which wants the fluctuations to be pathological (grand-canonical catastrophe) and incompatible with spontaneous symmetry braking, calls for a comprehensive rethinking of the approach to the problem. In this pap…

Crockett questions Melania Trump's reported 'Einstein visa': 'The math ain't mathin" (Tara Suter/The Hill)
https://thehill.com/homenews/house/5370991-crockett-melania-einstein-visa-question/
http://www.memeorandum.com/250626/p81#a250626p81

Explicit Symplectic Integrators for Massive Point Vortex Dynamics in Binary Mixture of Bose--Einstein Condensates
Tomoki Ohsawa
https://arxiv.org/abs/2506.03486

Explicit Symplectic Integrators for Massive Point Vortex Dynamics in Binary Mixture of Bose--Einstein Condensates
We construct explicit integrators for massive point vortex dynamics in binary mixture of Bose--Einstein condensates proposed by Richaud et al. The integrators are symplectic and preserve the angular momentum of the system exactly. Our main focus is the small-mass regime in which the minor component of the binary mixture comprises a very small fraction of the total mass. The solution behaviors in this regime change significantly depending on the initial momenta: they are highly oscillatory unles…

This https://arxiv.org/abs/2503.17248 has been replaced.
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Einstein's Cat -- A Thought Experiment Against Anti-Relativist Claims
When faced with overwhelming evidence supporting the reality of time dilation, confirmed in particular by the Hafele-Keating experiment, some anti-relativists reluctantly concede that time dilation applies to light clocks. However, they argue that the Theory of Relativity remains flawed, claiming that time dilation applies to light clocks only, not to massive objects. They assert that atomic clocks, which operate based on microwave radiation, merely create the illusion that the Hafele-Keating e…

Compact binary systems in Einstein-{\AE}ther gravity. II. Radiation reaction to 2.5 post-Newtonian order
Fatemeh Taherasghari, Clifford M. Will
https://arxiv.org/abs/2506.03843

Compact binary systems in Einstein-Æther gravity. II. Radiation reaction to 2.5 post-Newtonian order
We obtain the equations of motion for compact binary systems (black holes or neutron stars) in an alternative theory of gravity known as Einstein-AEther theory, which supplements the standard spacetime metric with a timelike four-vector (the AEther field) that is constrained to have unit norm. The equations make use of solutions obtained in Paper I for the gravitational and AEther field potentials within the near zone of the system, evaluated to 2.5 post-Newtonian (PN) order ($O(v/c)^5$ beyond …

This https://arxiv.org/abs/2505.05432 has been replaced.
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Boundary Energy-Momentum Tensors for Asymptotically Flat Spacetimes
We consider 3D and 4D asymptotically flat spacetimes near future null infinity endowed with the most general allowed Carroll geometry. We define a boundary energy-momentum tensor by varying the on-shell action with respect to the Carroll metric data. This requires adding counterterms to the Einstein-Hilbert action. We show that, in 4D, the shear is on par with the Carroll metric data. Their combined response defines a boundary energy-momentum-news complex whose diffeomorphism Ward identity is e…

Conformally compact metrics and the Lovelock tensors
Xinran Yu
https://arxiv.org/abs/2505.24188 https://arxiv.org/pdf/2505.24188

Conformally compact metrics and the Lovelock tensors
We study conformally compact metrics satisfying the Lovelock equations, which generalize the Einstein equation. We show that these metrics admit polyhomogeneous expansions, thereby naturally realizing the Fefferman-Graham expansion, which is an important tool in conformal geometry and the AdS/CFT correspondence. In even dimensions, we identify a boundary obstruction to smoothness near the boundary that generalizes the ambient obstruction tensor in the Einstein setting. Under appropriate regular…

I am against any nationalism, even in the guise of mere patriotism. Privileges based on position and property have always seemed to me unjust and pernicious, as did any exaggerated personality cult.
- Albert Einstein, My Credo, 1932
https://youtube.com/watch?v=9nRbyxVx3o0&si=hFh2vIVO_wqKkydM

This https://arxiv.org/abs/2506.00525 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hept…

Gravitomagnetism from Temporal Dimensional Reduction
We propose that the Taub-NUT metric can be envisaged as a (3+1) dimensional analog of the Kaluza-Klein (4+1) dimensional metric. After dimensional reduction of the Taub-NUT metric to (3) spatial dimensions, by treating time as the extra curled dimension (since the closed time-like curves can exist in the Taub-NUT framework, such a dimensional reduction is justified), we end up with three dimensional Einstein field equations plus the Maxwell equations for the gravitomagnetic field, which also ac…

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High-frequency backreaction for the Einstein equations under $\mathbb U(1)$ symmetry: from Einstein-dust to Einstein-Vlasov
C\'ecile Huneau, Jonathan Luk
https://arxiv.org/abs/2506.21779

High-frequency backreaction for the Einstein equations under $\mathbb U(1)$ symmetry: from Einstein-dust to Einstein-Vlasov
Given suitable small, localized, $\mathbb U(1)$-symmetric solutions to the Einstein-massless Vlasov system in an elliptic gauge, we prove that they can be approximated by high-frequency vacuum spacetimes. This extends previous constructions where the limiting spacetime solves the Einstein-(multiple) null dust system (i.e., where the limiting massless Vlasov field can be written as a finite sum of delta measures). The proof proceeds by first approximating solutions to the Einstein-massless Vlaso…

Timing and spectral studies of SRGA J144459.2$-$604207 with NICER, Einstein Probe, IXPE, NuSTAR, Insight-HXMT and INTEGRAL during its 2024 outburst
Zhaosheng Li, Lucien Kuiper, Yuanyue Pan, Renxin Xu, Yong Chen, Mingyu Ge, Yue Huang, Shumei Jia, Xiaobo Li, Liming Song, Jinlu Qu, Shu Zhang, Lian Tao, Hua Feng, Shuang-Nan Zhang, Maurizio Falanga
https:…

Timing and spectral studies of SRGA J144459.2$-$604207 with NICER, Einstein Probe, IXPE, NuSTAR, Insight-HXMT and INTEGRAL during its 2024 outburst
SRGA J144459.2$-$604207 is a newly confirmed accreting millisecond X-ray pulsar and type I X-ray burster. We present the broadband X-ray timing and spectral behaviors of SRGA J144459.2$-$604207 during its 2024 outburst. The data were collected from NICER, Einstein Probe, IXPE, Insight-HXMT, NuSTAR and INTEGRAL observations. X-ray pulsations have been detected for the 1.5$-$90 keV energy range throughout the `ON' phase of the outburst from MJD $\sim 60355-60385$. We refined the orbital and spi…

How One Quiet Man Became Everyone's Sage: The Spiritual Recasting of Einstein
Galina Weinstein
https://arxiv.org/abs/2505.19695 https://

How One Quiet Man Became Everyone's Sage: The Spiritual Recasting of Einstein
This paper critically examines the central thesis of Kieran Fox's "I Am a Part of Infinity: The Spiritual Journey of Albert Einstein"-namely, that Einstein's intellectual development constitutes a coherent spiritual path culminating in a form of pantheistic mysticism shaped by both Western and Eastern traditions. Fox presents Einstein as the modern heir to a long-suppressed lineage of rational spirituality, extending from Pythagoras and Spinoza to Vedanta and Buddhism, unified by wonder, revere…

Scalable inference of large-scale random kronecker graphs via tensor decomposition and Einstein summation
Sanaa Khobizy
https://arxiv.org/abs/2506.22292 ht…

Scalable inference of large-scale random kronecker graphs via tensor decomposition and Einstein summation
In this paper, we extend the analysis of random Kronecker graphs to multi-dimensional networks represented as tensors, enabling a more detailed and nuanced understanding of complex network structures. We decompose the adjacency tensor of such networks into two components: a low-rank signal tensor that captures the essential network structure and a zero-mean noise tensor that accounts for random variations. Building on recent advancements in tensor decomposition and random tensor theory, we intr…

Multi-mode cooling of a Bose-Einstein condensate with linear quantum feedback
Zain Mehdi, Matthew L. Goh, Matthew J. Blacker, Joseph J. Hope, Stuart S. Szigeti
https://arxiv.org/abs/2506.02377

Multi-mode cooling of a Bose-Einstein condensate with linear quantum feedback
We theoretically investigate measurement-based feedback control over the motional degrees of freedom of an oblate quasi-2D atomic Bose-Einstein condensate (BEC) subject to continuous density monitoring. We develop a linear-quadratic-Gaussian (LQG) model that describes the multi-mode dynamics of the condensate's collective excitations under continuous measurement and control. Crucially, the multi-mode cold-damping feedback control we consider uses a realistic state-estimation scheme that does no…

This https://arxiv.org/abs/2412.08693 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hept…

Random Circuits in the Black Hole Interior
In this paper, we present a quantitative holographic relation between a microscopic measure of randomness and the geometric length of the wormhole in the black hole interior. To this end, we perturb an AdS black hole with Brownian semiclassical sources, implementing the continuous version of a random quantum circuit for the black hole. We use the random circuit to prepare ensembles of states of the black hole whose semiclassical duals contain Einstein-Rosen (ER) caterpillars: long cylindrical w…

This https://arxiv.org/abs/2501.18787 has been replaced.
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Quantitative Derivation of the Two-Component Gross--Pitaevskii Equation in the Hard-Core Limit with Uniform-in-Time Convergence Rate
We derive the time-dependent two-component Gross--Pitaevskii (GP) equation as an effective description of the dynamics of a dilute two-component Bose gas near its ground state, which exhibits a two-component Bose-Einstein condensate, in the GP limit. Our main result establishes a uniform-in-time bound on the convergence rate between the many-body dynamics and the effective description, explicitly quantified in terms of the particle number $N$, and also implies a uniform-in-time bound for the on…

Dynamical dark energy in the no-scale Brans-Dicke gravity
Muzi Hong, Kyohei Mukaida, Tsutomu T. Yanagida
https://arxiv.org/abs/2506.01543 https://

Dynamical dark energy in the no-scale Brans-Dicke gravity
We add a new scalar field in the no-scale Brans-Dicke gravity and require it to have a global O(2) symmetry with the original scalar field in the Brans-Dicke gravity. This gives us a new massless scalar field in the Einstein frame due to the SO(2) symmetry. We then explicitly break the O(2) symmetry to a $D_4$ symmetry, and this scalar field gains a periodic potential. This scalar field can serve as the quintessence field to explain dark energy. If we further add the $R^2$ term and the non-mini…

Zahlen, bitte! Albert Einsteins 8-Minuten-Streit um die Sonne
Wirkt sich die explodierende Sonne sofort oder erst nach 8 Minuten auf die Erde aus? Zu der Diskussion schuf Einstein 1915 die Allgemeine Relativitätstheorie.

ML-Driven Strong Lens Discoveries: Down to $\theta_E \sim 0.03''$ and $M_\mathrm{halo}< 10^{11} M_\odot$
Ethan Silver, R. Wang, Xiaosheng Huang, A. Bolton, C. Storfer, S. Banka
https://arxiv.org/abs/2507.01943

ML-Driven Strong Lens Discoveries: Down to $θ_E \sim 0.03''$ and $M_\mathrm{halo}< 10^{11} M_\odot$
We present results on extending the strong lens discovery space down to much smaller Einstein radii ($θ_E\lesssim0.03''$) and much lower halo mass ($M_\mathrm{halo}<10^{11}M_\odot$) through the combination of JWST observations and machine learning (ML) techniques. First, we forecast detectable strong lenses with JWST using CosmoDC2 as the lens catalog, and a source catalog down to 29th magnitude. By further incorporating the VELA hydrodynamical simulations of high-redshift galaxies, we simulat…

Super high capacity of silicon carbon anode over 6500 mAh g-1 for lithium battery
Shisheng Lin, Minhui Yang, Zhuang Zhao, Mingjia Zhi, Xiaokai Bai
https://arxiv.org/abs/2507.02704

Super high capacity of silicon carbon anode over 6500 mAh g-1 for lithium battery
As silicon is approaching its theoretical limit for the anode materials in lithium battery, searching for a higher limit is indispensable. Herein, we demonstrate the possible of achieving ultrahigh capacity over 6500 mAh g-1 in silicon-carbon composites. Considering the numerous defects inside the silicon nanostructures, it is deduced the formation of quasi-Bose Einstein condensation should be possible, which can lead to the low viscosity flow of lithium-ions through the anode. At a charge-disc…

On the polemic assessment of what Bell did
Justo Pastor Lambare
https://arxiv.org/abs/2506.22915 https://arxiv.org/pdf/2506.22915

On the polemic assessment of what Bell did
Despite their Nobel Prize-winning empirical falsification, the interpretation of the Bell inequality remains a subject of controversy. This article discusses and attempts to clarify the reasons John S. Bell and A. Einstein claimed that quantum entanglement implies puzzling nonlocal correlations that Einstein famously termed ``spooky action at a distance.'' The issue remains highly controversial and has roughly divided the scientific community into localists and nonlocalists. Without taking a st…

Perturbations of Einstein-Maxwell-phantom spacetime: Instabilities of charged Ellis wormholes and quasinormal modes of black holes
Guan-Yu Wu, Si-Yu Wang, Yan-Gang Miao
https://arxiv.org/abs/2507.02258

Perturbations of Einstein-Maxwell-phantom spacetime: Instabilities of charged Ellis wormholes and quasinormal modes of black holes
Phantom scalar fields, as a viable candidate for dark energy, have been instrumental in eliminating spacetime singularities and constructing wormholes and regular black holes. We investigate the Einstein-Maxwell-phantom (EMP) framework, in which the Ellis wormholes can be charged and regular black holes can be admitted. While the previous study has shown the stability of EMP wormholes under massless scalar field perturbations, we further perform a comprehensive linear analysis of the EMP spacet…

Hidden Bose-Einstein Singularities in Correlated Electron Systems: III. Thermodynamic Signals
Takafumi Kita
https://arxiv.org/abs/2506.19211 https://

Hidden Bose-Einstein Singularities in Correlated Electron Systems: III. Thermodynamic Signals
We study thermodynamic consequences of the hidden Bose-Einstein singularities, which have been predicted to cause a pseudogap phase, based on quantum field theory of ordered phases. Starting from the Luttinger-Ward functional for the grand thermodynamic potential, we derive expressions of the Helmholtz free energy, internal energy, entropy, and heat capacity in a form suitable for numerical studies. They are applied to the weakly attractive Hubbard model in three dimensions to calculate the the…

Wish I could vote for her.
‘Math ain’t mathin’: Jasmine Crockett torches Melania Trump over 'Einstein visa' - Raw Story
https://www.rawstory.com/jasmine-crockett-trump-2672436329/

New modeling of the stray light noise in the main arms of the Einstein Telescope
M. Andr\'es-Carcasona, J. Grandes Umbert, D. Gonz\'alez-Lociga, M. Mart\'inez, Ll. M. Mir, H. Yamamoto
https://arxiv.org/abs/2506.18083

New modeling of the stray light noise in the main arms of the Einstein Telescope
Stray light represents a significant noise source for gravitational wave detectors, requiring an accurate modeling and mitigation to preserve the experiment's sensitivity. In this article, we present an updated and improved analysis of the stray-light induced noise in the Einstein Telescope main arm. The results presented here supersede previous studies taking into account a number of improvements, including baffle clipping effects, new numerical calculations for computing diffraction contribut…

The idea is to provide a safe haven and a fertile ground for the next generation of scientists to work in peace and freedom to solve the most significant challenges of our time; but the geopolitical argument will prevail. As Jorge Luis Borges said in his short story “Nathaniel Hawthorne” from his book “Other Inquisitions” (1952):
“The past is indestructible; sooner or later all things return, and one of the things that return is the project to abolish the past.”

William Aspray
There was a moment in which Kurt Gödel, Albert Einstein, and John von Neumann were all roaming the halls of the Institute for Advanced Studies in Princeton at the same time. Let that information sink in. Humanity experiences such gatherings of brilliant minds in a remote location of the space-time continuum only every so often; maybe the ancient Greeks and the men of the Renaissance witnessed such periods in time, as did the IAS staff at the end of World War II. How much will we have to wait f…

Novel black holes with scalar hair in the Einstein-Maxwell-Scalar Theory with positive coupling
Hong Guo, Wei-Liang Qian, Bean Wang
https://arxiv.org/abs/2506.02445

Novel black holes with scalar hair in the Einstein-Maxwell-Scalar Theory with positive coupling
In this work, we find a new branch of hairy black hole solutions in the Einstein-Maxwell-Scalar (EMS) theory in four-dimensional asymptotically flat spacetimes. Different from spontaneous scalarization induced by tachyonic instabilities in Reissner-Nordström (RN) black holes with a negative coupling parameter, these scalar-hairy black hole solutions arise when the coupling parameter is positive, where nonlinear coupling plays the dominant role, meaning that the coupling is positively correlate…

The Instrumental Background of EP/FXT
Juan Zhang, Yong Chen, Shumei Jia, Haisheng Zhao, WeiWei Cui, Tianxiang Chen, Juan Wang, Hao Wang, Jin Wang, Chengkui Li, Xiaofan Zhao, Ju Guan, Dawei Han, Jingjing Xu, Liming Song, Hua Feng, Shuangnan Zhang, Weimin Yuan
https://arxiv.org/abs/2507.00510

The Instrumental Background of EP/FXT
The in-flight instrumental background of the Follow-up X-ray Telescope (FXT) onboard Einstein Probe (EP) mission is analysed in this work by utilizing observations collected during Performance Verification phase and subsequent dedicated filter wheel closed observations. The instrumental backgrounds of the two FXT modules are consistent with each other, with an average rate of $\sim 4\times10^{-2}$\,counts/s/keV at 0.5--10\,keV for each module. The background is nearly uniformly distributed acro…

This https://arxiv.org/abs/2410.23818 has been replaced.
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Acceleration-induced transport of quantum vortices in joined atomtronic circuits
Persistent currents--inviscid quantized flow around an atomic circuit--are a crucial building block of atomtronic devices. We investigate how acceleration influences the transfer of persistent currents between two density-connected, ring-shaped atomic Bose-Einstein condensates, joined by a tunable weak link that controls system topology. We find that the acceleration of this system modifies both the density and phase dynamics between the rings, leading to a bias in the periodic vortex oscillati…

#EinsteinQuotes

On the Parallels Between Minimal Surfaces and Einstein Four-Manifolds
Mia Beard
https://arxiv.org/abs/2506.14972 https://arxiv.org/pd…

On the Parallels Between Minimal Surfaces and Einstein Four-Manifolds
Minimal surfaces and Einstein manifolds are among the most natural structures in differential geometry. Whilst minimal surfaces are well understood, Einstein manifolds remain far less so. This exposition synthesises together a set of parallels between minimal surfaces embedded in an ambient three-manifold, and Einstein four-manifolds. These parallels include variational formulations, topological constraints, monotonicity formulae, compactness and epsilon-regularity theorems, and decompositions …

Semiclassical evolution of a dynamically formed spherical black hole with an inner horizon
Valentin Boyanov, David Hilditch, Artur Semi\~ao
https://arxiv.org/abs/2506.04845

Semiclassical evolution of a dynamically formed spherical black hole with an inner horizon
In this work we obtain a numerical self-consistent spherical solution of the semiclassical Einstein equations representing the evaporation of a trapped region which initially has both an outer and an inner horizon. The classical matter source used is a static electromagnetic field, allowing for an approximately Reissner-Nordström black hole as the initial configuration, where the charge sets the initial scale of the inner horizon. The semiclassical contribution is that of a quantum scalar fiel…

Moir\'e-Polaritons in a Dark Bose-Einstein Condensate
Moroni Santiago-Garc\'ia, Shunashi G. Castillo-L\'opez, David A. Ruiz-Tijerina, Arturo Camacho-Guardian
https://arxiv.org/abs/2506.15083

Moiré-Polaritons in a Dark Bose-Einstein Condensate
Quantum mixtures of moiré excitons have arisen as a platform for realizing novel phases of light and matter. Here, we study moiré polaritons coupled to a Bose-Einstein condensate of dark-state excitons confined to a moiré superlattice. We develop a variational approach to analyze the optical response of the system and demonstrate that strong exciton-exciton interactions significantly modify the character of moiré polaritons, leading to sizable energy shifts of the avoided crossing between t…

Se os fatos não de adaptam Š teoria, mude os fatos.
-- Albert Einstein

This https://arxiv.org/abs/2504.04979 has been replaced.
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Light quark energy loss in the flavor-dependent systems from holography
Using the holographic model of finite-endpoint-momentum shooting string approach, we study the instantaneous energy loss of light quarks for the flavor-dependent systems with $N_f = 0$, $N_f = 2$, and $N_f = 2+1$ in the Einstein-Maxwell-dilaton (EMD) framework. In particular, we investigate for the first time the impact of the flavor content of the strongly coupled QGP medium on the instantaneous energy loss of light quarks. It turns out that the instantaneous energy loss of light quarks is sma…

Multi-mode feedback cooling of the collective modes of a Bose-Einstein condensate
Ryan J. Thomas, Jordan A. McMahon, Zain Mehdi, Stuart S. Szigeti, Simon A. Haine, Samuel Legge, John D. Close, Joseph J. Hope
https://arxiv.org/abs/2506.19739

Multi-mode feedback cooling of the collective modes of a Bose-Einstein condensate
We experimentally demonstrate cavity-free feedback cooling of the three lowest-lying collective modes of a Bose-Einstein condensate in a prolate harmonic trap. Using shadowgraph imaging as an \textit{in situ} probe of the atomic density, we measure the time-dependent centers-of-mass and widths of the condensate in two dimensions and use these measurements to damp oscillations in the two visible dipole modes and the low-frequency quadrupole mode. By inducing oscillations in the condensate, we sh…

Dynamics of a dark soliton in a curved 1D Bose-Einstein condensate
Jorge A. G. Attie, Emanuel A. L. Henn
https://arxiv.org/abs/2507.01157 https://

Dynamics of a dark soliton in a curved 1D Bose-Einstein condensate
We investigate the nonlinear dynamics of dark solitons in a one-dimensional Bose-Einstein condensate confined to a curved geometry. Using the Gross-Pitaevskii equation in curvilinear coordinates and a perturbative expansion in the local curvature, we derive a set of coupled evolution equations for the soliton velocity and the curvature. For the case of constant curvature, such as circular geometries, the soliton dynamics is governed solely by the initial velocity and curvature. Remarkably, the …

Shadow constraints of charged black hole with scalar hair and gravitational waves from extreme mass ratio inspirals
Lai Zhao, Meirong Tang, Zhaoyi Xu
https://arxiv.org/abs/2506.04971

Shadow constraints of charged black hole with scalar hair and gravitational waves from extreme mass ratio inspirals
Black hole (BH) shadow observations and gravitational wave astronomy have become crucial approaches for exploring BH physics and testing gravitational theories in extreme environments. This paper investigates the charged black hole with scalar hair (CBH-SH) derived from the Einstein-Maxwell-conformal coupled scalar (EMCS) theory. We first constrain the parameter space $(Q/M, s/M^2)$ of the BH using the Event Horizon Telescope (EHT) observations of M87* and Sgr A*. The results show that M87* pro…

Shape Shifting Light Dark Matter Solitons
Dor Ben-Amotz
https://arxiv.org/abs/2506.01282 https://arxiv.org/pdf/2506.01282

Shape Shifting Light Dark Matter Solitons
Dark matter consisting of a Bose-Einstein-Condensate (BEC) of ultra-light particles is predicted to have a soliton shape that shifts with the dark matter mass fraction in galaxies with a centrally localized stellar mass (such as a black hole). In the self-gravitating dark matter limit, the predicted cored soliton shape is consistent with previous numerical predictions and analytical approximations. As the dark matter mass fraction decreases, the soliton is predicted to become increasingly cusp …

Multi-messenger observations of binary neutron star mergers: synergies between the next generation gravitational wave interferometers and wide-field, high-multiplex spectroscopic facilities
S. Bisero, S. D. Vergani, E. Loffredo, M. Branchesi, N. Hazra, U. Dupletsa, R. I. Anderson
https://arxiv.org/abs/2507.02055

Multi-messenger observations of binary neutron star mergers: synergies between the next generation gravitational wave interferometers and wide-field, high-multiplex spectroscopic facilities
Third-generation gravitational wave (GW) observatories such as the Einstein Telescope (ET) and Cosmic Explorer (CE) will detect hundreds of thousands of binary neutron star (BNS) mergers, reaching redshifts beyond $z\sim3$. To fully exploit joint GW and electromagnetic (EM) detections, dedicated strategies and adapted EM facilities are essential. We investigate the role of Integral Field and Multi-Object Spectroscopy (IFS and MOS) with the Wide-field Spectroscopic Telescope (WST) on next genera…

Detectability and Parameter Estimation for Einstein Telescope Configurations with GWJulia
Andrea Begnoni, Stefano Anselmi, Mauro Pieroni, Alessandro Renzi, Angelo Ricciardone
https://arxiv.org/abs/2506.21530

Detectability and Parameter Estimation for Einstein Telescope Configurations with GWJulia
Future gravitational-wave (GW) detectors are expected to detect tens of thousands of compact binary coalescences (CBC) per year, depending also on the final detectors layout. For this reason, it is essential to have a fast, reliable tool for forecasting how different detector layouts will affect parameter estimation for these events. The Fisher Information Matrix (FIM) is a common tool for tackling this problem. In this paper, we present a new open source code GWJulia to perform FIM analysis of…

Gravitational Wave Signatures of Periodic Motion near Higher-Derivative Einstein-\AE ther Black Holes
Sayantan Choudhury, Md Khalid Hossain, Gulnur Bauyrzhan, Koblandy Yerzhanov
https://arxiv.org/abs/2507.00904

Gravitational Wave Signatures of Periodic Motion near Higher-Derivative Einstein-Æther Black Holes
Higher-derivative modifications of general relativity are generically expected from effective field theory approaches to quantum gravity, and they arise naturally in Lorentz-violating theories such as Einstein-Ether gravity. In this work, we investigate black hole spacetimes within Einstein-Ether theory supplemented by quadratic curvature corrections, including terms proportional to $R^2$, $R_{μν} R^{μν}$, and $R_{μνλρ} R^{μνλρ}$. We derive the corrected static, spherically symmetri…

The first of four videos by Dr Jorge Diaz:
Einstein's groundbreaking work on radiation that set the basis of the laser and paved the way to Heisenberg's Matrix Mechanics 🧪⚛️ #chemsky
https://youtu.be/_lC6-RUI7PQ

Locally Rotationally Symmetric Spacetimes in Einstein-Cartan Theory and Their Classification
Ujjwal Agarwal, Sante Carloni
https://arxiv.org/abs/2507.01840

Locally Rotationally Symmetric Spacetimes in Einstein-Cartan Theory and Their Classification
We present the complete set of covariant equations that govern the locally rotationally symmetric torsion spacetimes sourced by Weyssenhoff fluid in Einstein-Cartan-Sciama-Kibble gravity. Using these equations, we can explore in detail the peculiar relationship between conformal structure and torsion. We develop a comprehensive scheme to categorize these torsional spacetimes into distinct classes. We explicitly analyze the properties of each class and obtain novel analytical solutions to the gr…

Comparison of total $\sigma_k$-curvature
Jiaqi Chen, Yufei Shan, Yinghui Ye
https://arxiv.org/abs/2505.23440 https://arxiv.org/pdf/25…

Comparison of total $σ_k$-curvature
Volume comparison theorem is a type of fundamental results in Riemannian geometry. In this article, we extend the volume comparison result in \cite{Besse2008} to the comparison of total $σ_l$-curvature with respect to $σ_k$-curvature ($l

This https://arxiv.org/abs/2306.15290 has been replaced.
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On boundary degrees of freedom in three dimensional Anti-de Sitter spacetime and thermofield-double
We will give two representations for thermofield-double (TFD). The first representation is the well-known Kerr-BTZ black hole geometry, which is the solution of Einstein's equation. The second representation is a disjoint union of two circles, which is a solution to two copies of the Schwarzian theory. This representation, in particular, admits the reparametrization modes, which are absent in any two dimensional CFT on a torus, and are essential for (dis-)entangling the TFD. Since the two repre…

Computing the Bogoliubov-de Gennes excitations of two-component Bose-Einstein condensates
Manting Xie, Yong Zhang
https://arxiv.org/abs/2506.12688 https://…

Computing the Bogoliubov-de Gennes excitations of two-component Bose-Einstein condensates
In this paper, we present an efficient and spectrally accurate numerical method to compute elementary/collective excitations in two-component Bose-Einstein condensates (BEC), around their mean-field ground state, by solving the associated Bogoliubov-de Gennes (BdG) equation. The BdG equation is essentially an eigenvalue problem for a non-Hermitian differential operator with an eigenfunction normalization constraint. Firstly, we investigate its analytical properties, including the exact eigenpai…

Spontaneous Quantum Turbulence in a Newborn Bose-Einstein Condensate via the Kibble-Zurek Mechanism
Seong-Ho Shinn, Matteo Massaro, Mithun Thudiyangal, Adolfo del Campo
https://arxiv.org/abs/2506.21670

Spontaneous Quantum Turbulence in a Newborn Bose-Einstein Condensate via the Kibble-Zurek Mechanism
The Kibble-Zurek mechanism (KZM) predicts the spontaneous formation of topological defects in a continuous phase transition driven at a finite rate. We propose the generation of spontaneous quantum turbulence (SQT) via the KZM during Bose-Einstein condensation induced by a thermal quench. Using numerical simulations of the stochastic projected Gross-Pitaevskii equation in two spatial dimensions, we describe the formation of a newborn Bose-Einstein condensate proliferated by quantum vortices. We…

This https://arxiv.org/abs/2407.02313 has been replaced.
link: https://scholar.google.com/scholar?q=a

A Casimir-like probe for 4D Einstein-Gauss-Bonnet gravity
Virtual transitions in a Casimir-like configuration are utilized to probe quantum aspects of four-dimensional Einstein-Gauss-Bonnet (4D EGB) gravity. This study employs a quantum optics-based approach, wherein an Unruh-DeWitt detector (modeled as a two-level atom) follows a radial timelike geodesic, falling freely into an uncharged, nonrotating black hole described by 4D EGB gravity, becoming thermalized in the usual Unruh manner. The black hole, asymptotically Minkowskian, is enclosed by a Cas…

Predictability of quantum observables: Applications in QKD and top quarks
Dennis I. Mart\'inez-Moreno, Miguel Castillo-Celeita, Diego G. Bussandri
https://arxiv.org/abs/2505.24502

Predictability of quantum observables: Applications in QKD and top quarks
We quantify and optimize the predictability of local observables in bipartite quantum systems by employing the Bayes risk and the inference variance, two measures rooted in statistical learning theory. Specifically, we minimized these quantities when the prediction is improved by an additional quantum system, providing analytical expressions for arbitrary two-qubit states, and showcasing a connection with Einstein-Podolsky-Rosen steering criteria. Then, we embed our Bayes risk minimization into…

Stability of non-supersymmetric vacua from calibrations
Vincent Menet, Alessandro Tomasiello
https://arxiv.org/abs/2507.02787 https://

Stability of non-supersymmetric vacua from calibrations
Supersymmetric vacua are protected from vacuum decay by energy positivity. No such argument is known for any non-supersymmetric vacua. In this paper, we try to extend to the latter a simpler argument based on calibrations, to at least protect them from decays mediated by D-brane bubbles, including their abelian bound states. We examine several classes of AdS$_4$ and AdS$_5$ solutions in type II string theory, including some new ones, involving coset spaces, sphere fibrations, Kähler--Einstein …

Rotating Black Holes in Einstein-Born-Infeld Theory
Lang Cheng, Peng Wang
https://arxiv.org/abs/2507.00879 https://arxiv.org/pdf/2507…

Rotating Black Holes in Einstein-Born-Infeld Theory
We numerically construct a family of stationary, axisymmetric black hole solutions in Einstein-Born-Infeld theory, incorporating both electric charge and rotation. Our results indicate that when nonlinear electromagnetic effects are weak, rotating BI black holes with fixed spin approach the extremal limit as the electric charge increases. In contrast, strong nonlinear effects lead to the termination of solutions at configurations corresponding to naked singularities. We demonstrate that nonline…

Some isolation and stability results for Einstein manifolds
Letizia Branca, Klaus Kroencke
https://arxiv.org/abs/2506.13248 https://a…

Some isolation and stability results for Einstein manifolds
We prove new isolation and stability results for Einstein manifolds in a variety of settings. Imposing conditions on the Weyl tensor, we establish new stability criteria for compact, asymptotically hyperbolic (AH) and asymptotically locally Euclidean (ALE) manifolds and an isolation result in the latter setting. For compact Kähler and Sasaki $η$-Einstein manifolds, we provide similar results which involve the Bochner tensor and the contact Bochner tensor, respectively.

The 60-year-old man lying on the street, as far as anyone knew, was just a janitor hit by a drunk driver.
There was no mention of it on the local news, no obituary in the morning paper.
His name might have been Anonymous. But it wasn’t. 
His name was Peter Putnam.
He was a physicist who’d hung out with Albert Einstein, John Archibald Wheeler, and Niels Bohr,
and two blocks from the crash, in his run-down apartment, where his partner, Claude, was startled by a scr…

Finding Peter Putnam
The forgotten janitor who discovered the logic of the mind

Einstein causality of quantum measurements in the Tomonaga-Schwinger picture
Samuel Fedida
https://arxiv.org/abs/2506.14693 https://a…

Einstein causality of quantum measurements in the Tomonaga-Schwinger picture
When quantum measurements are conducted over spacelike-separated regions of spacetime, a natural and commonly assumed physical postulate, called Einstein causality, asserts that they should commute. In this paper, we provide a generalisation to Lüders' rule à la Aharonov-Albert in those globally hyperbolic spacetimes which allow unitarily equivalent Hilbert spaces to be defined along Cauchy hypersurfaces, thus relying on the existence of an interaction picture à la Tomonaga-Schwinger. We sho…

Entanglement on a Sphere
Konstantinos Boutivas, Dimitrios Katsinis, Georgios Pastras, Nikolaos Prountzos, Nikolaos Tetradis
https://arxiv.org/abs/2507.01174

Entanglement on a Sphere
We study the entanglement entropy of a massive scalar field in the background of the Einstein universe. We determine numerically the structure of the UV-divergent terms. We study analytically the IR term that originates in the long-range correlations arising from the field zero mode on the sphere. We compare with previous results for a scalar field in a dS or AdS background.

Linear stability of Perelman's $\nu$-entropy of standard Einstein manifolds
Emilio A. Lauret, Alejandro Tolcachier
https://arxiv.org/abs/2506.12435 htt…

Linear stability of Perelman's $ν$-entropy of standard Einstein manifolds
Paul Schwahn recently exhibited 112 non-symmetric, connected, simply connected, compact Einstein manifolds that are stable with respect to the total scalar curvature functional restricted to the space of Riemannian metrics with constant scalar curvature and fixed volume. This stability follows from the inequality $λ_L > 2E$, where $λ_L$ denotes the smallest eigenvalue of the Lichnerowicz Laplacian on TT-tensors and $E$ is the corresponding Einstein factor. In this paper, we estimate the sma…

This https://arxiv.org/abs/2502.17267 has been replaced.
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Global monopole in a Ricci-coupled Kalb-Ramond bumblebee gravity
In this paper, we investigate black hole solutions in Einstein-Kalb-Ramond (EKR) bumblebee gravity sourced by a global monopole characterized by the charge $η$. This modified theory of gravity possesses the notable feature of incorporating local Lorentz symmetry breaking (LSB) via a spontaneous symmetry-breaking mechanism. We solve the field equations for a static and spherically symmetric metric with the Kalb-Ramond (KR) field fixed at its VEV, thereby obtaining new black hole solutions. Thes…

This https://arxiv.org/abs/2504.05549 has been replaced.
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Fast and direct preparation of a genuine lattice BEC via the quantum Mpemba effect
We present an efficient method for dissipatively preparing a Bose-Einstein condensate (BEC) directly on a lattice, avoiding the need for a two-staged preparation procedure currently used in ultracold-atom platforms. Our protocol is based on driving the lattice-subsystem into a non-equilibrium steady state, which we show to exhibit a lattice analog of a true BEC, where the depletion can be controlled via the dissipation strength. Furthermore, exploiting a symmetry-based Mpemba effect, we analyti…

Bose-Einstein Condensate Dark Matter in the Core of Neutron Stars: Implications for Gravitational-wave Observations
Samanwaya Mukherjee, P. S. Aswathi, Chiranjeeb Singha, Apratim Ganguly
https://arxiv.org/abs/2506.22353

Bose-Einstein Condensate Dark Matter in the Core of Neutron Stars: Implications for Gravitational-wave Observations
We thoroughly investigate the scenario where dark matter is admixed with the ordinary nuclear matter in a neutron star, focusing on the finite temperature Bose-Einstein condensate (BEC) as the dark matter candidate. These hybrid configurations yield masses and radii that match observed values of pulsar mass-radius observation and adhere to dimensionless tidal Love number constraints from the binary neutron star merger event GW170817. By analyzing possible, stable mass-radius configurations and …

Gravitomagnetism from Temporal Dimensional Reduction
Mehran Z-Abyaneh, Mehrdad Farhoudi
https://arxiv.org/abs/2506.00525 https://arxi…

Gravitomagnetism from Temporal Dimensional Reduction
We propose that the Taub-NUT metric can be envisaged as a (3+1) dimensional analog of the Kaluza-Klein (4+1) dimensional metric. After dimensional reduction of the Taub-NUT metric to (3) spatial dimensions, by treating time as the extra curled dimension (since the closed time-like curves can exist in the Taub-NUT framework, such a dimensional reduction is justified), we end up with three dimensional Einstein field equations plus the Maxwell equations for the gravitomagnetic field, which also ac…

Analytic Phase Solution and Point Vortex Model for Dipolar Quantum Vortices
Ryan Doran, Thomas Bland
https://arxiv.org/abs/2507.02779 https://

Analytic Phase Solution and Point Vortex Model for Dipolar Quantum Vortices
We derive an analytic expression for the phase of a quantum vortex in a dipolar Bose-Einstein condensate, capturing anisotropic effects from long-range dipole-dipole interactions. This solution provides a foundation for a dipolar point vortex model (DPVM), incorporating both phase-driven flow and dipolar forces. The DPVM reproduces key features of vortex pair dynamics seen in full simulations, including anisotropic velocities, deformed orbits, and directional motion, offering a minimal and accu…

Polarization properties of photon Bose-Einstein condensates
Sven Enns, Julian Schulz, Kirankumar Karkihalli Umesh, Frank Vewinger, Georg von Freymann
https://arxiv.org/abs/2506.06141

Polarization properties of photon Bose-Einstein condensates
The first experimental realization of a photon Bose-Einstein condensate was demonstrated more than a decade ago. However, the polarization of the condensate has not been fully understood and measured in this weakly driven-dissipative system. In this letter, we experimentally investigate the polarization of thermal and condensed light depending on the power and polarization of the pump beam. With full control over the polarization of the pump, it is possible to create arbitrary states on the sur…

Synergistic Effects of Spin-Orbit Coupling and Intercomponent Interactions in Two-Component (2 1)D Photonic Fields
Suri Deekshita, S. Sanjay, S. Saravana Veni, Conrad B. Tabi, Timoleon C. Kofane
https://arxiv.org/abs/2507.02505

Synergistic Effects of Spin-Orbit Coupling and Intercomponent Interactions in Two-Component (2+1)D Photonic Fields
The study investigates the formation, stability and dynamic advancement of two-dimensional vortex quantum droplets within binary Bose-Einstein condensates (BECs), shaped by the interplay of photonic spin-orbit coupling (SOC) and quantum fluctuation effects. SOC leads to significant droplet stretching, resulting in vortex clusters forming in each component. The competition between photonic SOC and Lee-Huang-Yang (LHY) interactions introduces vortices into the condensate, described by the numeric…

This https://arxiv.org/abs/2505.23679 has been replaced.
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Boundary terms in cosmology
In the derivation of the Einstein field equations via Hamilton's principle, the inclusion of a boundary term is essential to render the variational problem well-posed, as it addresses variations that do not vanish at the boundary of the spacetime manifold. Typically, this term is chosen as the Gibbons-Hawking-York boundary term. In this work, we propose an alternative treatment of the boundary term within a cosmological framework by employing the Lagrange multiplier method. This approach enforc…

Hermitian-Einstein Metrics on Parabolic Bundles over compact complex surfaces
Xilun Li, Gang Tian
https://arxiv.org/abs/2506.15458 https://

Hermitian-Einstein Metrics on Parabolic Bundles over compact complex surfaces
We prove the Kobayashi-Hitchin correspondence for parabolic bundles over compact nonKähler surfaces with simple normal crossing divisor or compact nonKähler manifolds of any dimension with smooth divisor.

Strong hyperboloidal compactification for the spherical DF-GHG formulation of GR
Christian Peterson, David Hilditch
https://arxiv.org/abs/2506.03078 https:…

Strong hyperboloidal compactification for the spherical DF-GHG formulation of GR
The use of compactified hyperboloidal coordinates for metric formulations of the Einstein field Equations introduces formally singular terms in the equations of motion whose numerical treatment requires care. In this paper we study a particular choice of constraint addition, choice of gauge and reduction fields in order to minimize the number of these terms in a spherically symmetric reduction of the Dual-Foliation Generalized Harmonic Gauge formulation of General Relativity. We proceed to the …

Progress in Einstein-Cartan gravity
Mikhail Shaposhnikov
https://arxiv.org/abs/2506.11847 https://arxiv.org/pdf/2506.11847

Progress in Einstein-Cartan gravity
It is well-known that the gravitational force can be obtained by gauging the Lorentz group, which puts gravity on the same footing as the Standard Model fields. The resulting theory - Einstein-Cartan gravity - has several crucial advantages. I will overview the construction of the Weyl-invariant version of this theory and discuss its applications in particle physics and cosmology, in particular for inflation and the strong CP problem.

Performance of multiple filter-cavity schemes for frequency-dependent squeezing in gravitational-wave detectors
Jacques Ding, Eleonora Capocasa, Isander Ahrend, Fangfei Liu, Yuhang Zhao, Matteo Barsuglia
https://arxiv.org/abs/2506.02222

Performance of multiple filter-cavity schemes for frequency-dependent squeezing in gravitational-wave detectors
Gravitational-wave detectors use state-of-the-art quantum technologies to circumvent vacuum fluctuations via squeezed states of light. Future detectors such as Einstein Telescope may require the use of two filter cavities or a 3-mirror, coupled filter cavity to achieve a complex rotation of the squeezing ellipse in order to reduce the quantum noise over the whole detector bandwidth. In this work, we compare the theoretical feasibility and performances of these two systems and their resilience w…

Quintessence dark energy model in non-linear $f(Q)$ theory with bulk-viscosity
Dinesh Chandra Maurya
https://arxiv.org/abs/2506.02543 https://

Quintessence dark energy model in non-linear $f(Q)$ theory with bulk-viscosity
In this study, we investigate a locally rotationally symmetric (LRS) Bianchi type-I cosmological model in non-linear form of $f(Q)$ gravity with observational constraints. We solved the modified Einstein's field equations with a viscous fluid source and got a hyperbolic solution. First, we apply MCMC analysis to the cosmic chronometer (CC) and Pantheon datasets to place observational constraints on model parameters. Using approximated model parameters, we study the cosmological parameters, such…

Detecting Collective Excitations in Self-Gravitating Bose-Einstein Condensates via Faraday Waves
Ning Liu, Guodong Cheng
https://arxiv.org/abs/2506.18593 h…

Detecting Collective Excitations in Self-Gravitating Bose-Einstein Condensates via Faraday Waves
We propose Faraday waves as a probe for collective excitations in self-gravitating Bose-Einstein condensates (SGBECs), driven by periodic modulation of the $s$-wave scattering length. Linear stability analysis of the driven Gross-Pitaevskii-Newton equations reveals that parametric instability follows a Mathieu-like equation, with Faraday waves emerging resonantly when half the driving frequency matches the collective excitation frequency of the SGBEC. This framework yields a stability phase dia…

Expansion-contraction duality breaking in a Planck-scale sensitive cosmological quantum simulator
S. Mahesh Chandran, Uwe R. Fischer
https://arxiv.org/abs/2506.02719

Expansion-contraction duality breaking in a Planck-scale sensitive cosmological quantum simulator
We propose the experimental simulation of cosmological perturbations governed by a Planck-scale induced Lorentz violating dispersion, aimed at distinguishing between early-universe models with similar power spectra. Employing a novel variant of the scaling approach for the evolution of a Bose-Einstein condensate with both contact and dipolar interactions, we show that scale invariance, and in turn, the duality of the power spectrum is broken at large momenta for an inflating gas, and at small m…

Dynamical Dark Energy from $F(R)$ Gravity Models Unifying Inflation with Dark Energy: Confronting the Latest Observational Data
S. D. Odintsov, V. K. Oikonomou, G. S. Sharov
https://arxiv.org/abs/2506.02245

Dynamical Dark Energy from $F(R)$ Gravity Models Unifying Inflation with Dark Energy: Confronting the Latest Observational Data
A class of viable $F(R)$ gravity models which can provide a unified description of inflation with the dark energy era is confronted with the latest observational data on the dark energy era. These models have the unique characteristic that the de Sitter scalaron mass in the Einstein frame counterpart theory is a monotonic function of the curvature, which renders them viable descriptions for both the inflationary and the late-time acceleration eras. We also compare these models with other well-k…

Quantum droplets in rapidly rotating two-dimensional Bose-Einstein condensates
Zhen Cao, Siying Li, Zhendong Li, Xinyi Liu, Zhigang Wu, Mingyuan Sun
https://arxiv.org/abs/2506.17081

Quantum droplets in rapidly rotating two-dimensional Bose-Einstein condensates
Recent experiments demonstrate that rapidly rotating Bose-Einstein condensates (BECs) near the lowest Landau level can self-organize into interaction-driven persistent droplet arrays. Inspired by this discovery, we investigate the formation and dynamics of single droplet and droplet arrays in rapidly rotating BECs. Guided by a rigorous theorem on localized many-body states for 2D interacting systems in a magnetic field, we construct single droplet and droplet arrays states which are shown to be…

A Kaleidoscope of Topological Structures in Dipolar Bose-Einstein Condensates with Weyl-Like Spin-Orbit Coupling in Anharmonic Trap
Yun Liu, Zu-Jian Ying
https://arxiv.org/abs/2506.16734

A Kaleidoscope of Topological Structures in Dipolar Bose-Einstein Condensates with Weyl-Like Spin-Orbit Coupling in Anharmonic Trap
Dipole-dipole interaction (DDI) possesses characteristics different from the conventional isotropic s-wave interaction in Bose-Einstein condensates (BECs), the interplay of DDI with spin-orbit coupling (SOC) and rotation may induce novel quantum properties. We systematically analyze the effects of the DDI, Weyl-like SOC, rotation and trap anharmonicity in the ground state of two-componen BECs. The interplay of these factors leads to a kaleidoscope of quantum states of quantum defects and quantu…

Nonequilibrium quench dynamics of Bose-Einstein condensates of microwave-shielded polar molecules
Abdelaali Boudjemaa
https://arxiv.org/abs/2506.20835 http…

Nonequilibrium quench dynamics of Bose-Einstein condensates of microwave-shielded polar molecules
We theoretically investigate the non-equilibrium dynamics of homogeneous ultracold Bose gases of microwave-shielded polar molecules following a sudden quench of the scattering length at zero temperature. We calculate in particular the quantum depletion, the anomalous density, the condensate fluctuations, and the pair correlation function using both the time-dependent Bogoliubov approach and the self-consistent time-dependent Hartree-Fock-Bogoliubov approximation. During their time evolution, th…

Gravitational memory effects in Tachyon gravity
Pouneh Safarzadeh Ilkhchi, Amin Rezaei Akbarieh, Ali Seraj
https://arxiv.org/abs/2507.01879 https://…

Gravitational memory effects in Tachyon gravity
In this paper, we explore how a massless Tachyon field, when non-minimally coupled to gravity, affects gravitational memory, soft theorems, and symmetries near null infinity. We set up the model using both the Jordan and Einstein frames, work out the equations of motion and study the behavior of fields at large distances with the Bondi-Sachs gauge. The Tachyon adds a ``breathing'' polarization mode to the gravitational radiation, which modifies the Bondi mass loss formula and leaves a trace in …

Quantum Carpets of Higgs particles in a Supersolid
Koushik Mukherjee, Malte Schubert, Ralf Klemt, Thomas Bland, Tilman Pfau, Stephanie Reimann
https://arxiv.org/abs/2507.00989

Quantum Carpets of Higgs particles in a Supersolid
Supersolids formed from dipolar Bose-Einstein condensates (BECs) exhibit spontaneous density modulation while maintaining global phase coherence. This state of matter supports gapped amplitude (Higgs) excitations featuring a quadratic dispersion relation. While Higgs modes are typically strongly damped due to coupling with other amplitude and phase modes, imposing an experimentally realistic toroidal geometry allows us to numerically study the time evolution and dispersion of a localized Higgs …

Stealth black hole solutions in higher-order Maxwell-Einstein theories
Masato Minamitsuji
https://arxiv.org/abs/2506.11353 https://ar…

Stealth black hole solutions in higher-order Maxwell-Einstein theories
We study static and spherically symmetric black hole solutions in higher-order Maxwell-Einstein theories. We do not particularly focus on the degenerate classes of theories. For several specific choices of the coupling functions, we show that in the presence of the ordinary Maxwell kinetic term the Reissner-Nordström-(anti-)de Sitter solution in the pure Maxwell-Einstein theory can also be a solution in generic classes of higher-order Maxwell-Einstein theories, and in the absence of the ordina…

Weak null singularity for the Einstein-Euler system
Yuefeng Song
https://arxiv.org/abs/2506.16635 https://arxiv.org/pdf/2506.16635

Weak null singularity for the Einstein-Euler system
We study the behavior of a self-gravitating perfect relativistic fluid satisfying the Einstein-Euler system in the presence of a weak null terminal spacetime singularity. This type of singularities is expected in the interior of generic dynamical black holes. In the vacuum case, weak null singularities have been constructed locally by Luk, where the metrics extend continuously to the singularities while the Christoffel symbols fail to be square integrable in any neighborhood of any point on the…

This https://arxiv.org/abs/2412.07250 has been replaced.
initial toot: https://mastoxiv.page/@…

Control, competition and coexistence of effective magnetic orders by interactions in Bose-Einstein condensates with high-Q cavities
Ultracold atomic systems confined in optical cavities have been demonstrated as a laboratory for the control of quantum matter properties and analog quantum simulation. Often neglected, but soon amenable to manipulation in a new generation of experiments, we show that atomic many-body interactions allow additional control in the cavity driven self-organization of effective spinor Bose-Einstein condensates (BEC). We theoretically show that a rich landscape of magnetic ordering configurations eme…

This https://arxiv.org/abs/2412.06043 has been replaced.
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Probing Gravity -- Fundamental Aspects of Metric Theories and their Implications for Tests of General Relativity
Guided by the Einstein equivalence principle that identifies the phenomenon of gravitation as a manifestation of the dynamics of spacetime in contrast to a localizable force, we review and explore its consequences on formulating a theory of gravity. The resulting space of metric theories of gravity may address open conceptual and observational puzzles through a wealth of effects beyond general relativity, whose traces can be searched for within today's and tomorrow's gravitational testing groun…

This https://arxiv.org/abs/2505.14446 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_grqc_…

Light deflection in unified gravity and measurable deviation from general relativity
Light, though massless, does not travel in a perfectly straight line when it passes near a massive object. Instead, it follows the curvature of spacetime - a phenomenon predicted by Einstein's general theory of relativity. This effect, known as gravitational lensing, occurs because massive bodies like stars, galaxies, or black holes distort the fabric of spacetime around them, bending the path of light much like a lens bends rays in optics. In this work, we study gravitational lensing using the…

LQG inspired spacetimes as solutions of the Einstein equations
Marcos V. de S. Silva, Carlos F. S. Pereira, G. Alencar, Celio R. Muniz
https://arxiv.org/abs/2506.19818

LQG inspired spacetimes as solutions of the Einstein equations
Black bounces are compact objects with a wormhole structure hidden behind an event horizon. This type of metric can be obtained through general relativity by considering the presence of exotic matter. Such spacetimes can also arise within the framework of effective theories inspired by loop quantum gravity. In this work, we verify the possibility of obtaining black bounce models inspired by loop quantum gravity as solutions of general relativity. For this, we examine which sources can generate …

Quantum Uncertainties of Static Spherically Symmetric Spacetimes
Benjamin Koch, Ali Riahinia
https://arxiv.org/abs/2506.22545 https://

Quantum Uncertainties of Static Spherically Symmetric Spacetimes
We present a canonical quantization framework for static spherically symmetric spacetimes described by the Einstein-Hilbert action with a cosmological constant. In addition to recovering the classical Schwarzschild-(Anti)-de Sitter solutions via the Ehrenfest theorem, we investigate the quantum uncertainty relations that arise among the geometric operators in this setup. Our analysis uncovers an intriguing relation to black hole thermodynamics and opens a new angle towards generalized uncertain…

Helically twisted spacetime: study of geometric and wave optics, and physical analysis
Edilberto O. Silva, Frankbelson dos S. Azevedo, Faizuddin Ahmed
https://arxiv.org/abs/2506.23291

Helically twisted spacetime: study of geometric and wave optics, and physical analysis
We analyse a stationary, cylindrically symmetric spacetime endowed with an intrinsic helical twist, $ds^{2} = -dt^{2} + dr^{2} + r^{2} dϕ^{2} + (dz + ω\, r\,dϕ)^{2}$. Solving the Einstein equations exactly yields an anisotropic energy-momentum tensor whose density is negative and decays as $r^{-2}$, thus violating the weak energy condition near the axis. Three notable features emerge: (i) axis-centred negative energy; (ii) unequal transverse stresses; (iii) a torsional momentum flux $T_{ϕz}…

GW170817 Viable Einstein-Gauss-Bonnet Inflation Compatible with the Atacama Cosmology Telescope Data
S. D. Odintsov, V. K. Oikonomou
https://arxiv.org/abs/2506.08193

GW170817 Viable Einstein-Gauss-Bonnet Inflation Compatible with the Atacama Cosmology Telescope Data
In this work we investigate several Einstein-Gauss-Bonnet models that are compatible with the GW170817 event, the Atacama Cosmology Telescope data and the BICEP/Keck updated Planck constraints on the tensor-to-scalar ratio. We consider two distinct classes of Einstein-Gauss-Bonnet theories, which are equally successful for GW170817-compatible model building and we examine their viability against the Atacama Cosmology Telescope data and the updated Planck constraints on the tensor-to-scalar rati…

Measurements in stochastic gravity and thermal variance
Markus B. Fr\"ob, Dra\v{z}en Glavan, Paolo Meda
https://arxiv.org/abs/2506.23193 https://

Measurements in stochastic gravity and thermal variance
We analyze the thermal fluctuations of a free, conformally invariant, Maxwell quantum field (photon) interacting with a cosmological background spacetime, in the framework of quantum field theory in curved spacetimes and semiclassical and stochastic gravity. The thermal fluctuations give rise to backreaction effects upon the spacetime geometry, which are incorporated in the semiclassical Einstein-Langevin equation, evaluated in the cosmological Friedmann-Lemaître-Robertson-Walker spacetime. We…

Cosmology with Distinct Functions $f$ of the Non-metricity Scalar $Q$ : A Dynamical System Approach
Promila Biswas, Subhajit Pal, Ritabrata Biswas, Satyajit Pal
https://arxiv.org/abs/2506.21646

Cosmology with Distinct Functions $f$ of the Non-metricity Scalar $Q$ : A Dynamical System Approach
Symmetric teleparallel gravity is one among the general relativistic trinity which deals with the non-metricity scalar $Q$. In the Einstein Hilbert action, a function of $Q$ is chosen to be the main contributory part of the Lagrangian and a modified theory of gravity is constructed. In literature, different structures of the function of $Q$ are found which sustain several astrophysical observations like Big Bang nucleosynthesis, late-time cosmic acceleration etc. Autonomous systems for each suc…