General equilibrium second-order hydrodynamic coefficients for free quantum fields

This paper presents a systematic calculation of non-dissipative, quantum-origin second-order hydrodynamic corrections to the stress-energy tensor and currents for free boson and Dirac fields in thermal vorticity, deriving their Kubo formulae via equilibrium correlators and demonstrating that the axial current receives vorticity-proportional corrections independent of anomalous terms.

M. Buzzegoli (U. Florence), E. Grossi (U. Heidelberg), F. Becattini (U. Florence)2026-04-14⚛️ nucl-th

Validating Prior-informed Fisher-matrix Analyses against GWTC Data

This paper validates the accuracy of prior-informed Fisher-matrix analyses by comparing them against real gravitational-wave data from GWTCs, demonstrating that while priors are crucial for handling parameter degeneracies, the Fisher approximation remains a reliable tool for future Einstein Telescope science-case studies.

Ulyana Dupletsa, Jan Harms, Ken K. Y. Ng, Jacopo Tissino, Filippo Santoliquido, Andrea Cozzumbo2026-04-14⚛️ gr-qc

Optomechanical vector sensing of new forces at 6 micron separation

This paper reports a 100-fold improvement in sensitivity for detecting new gravity-like forces at micrometer scales using optically levitated microspheres, establishing the first multi-component vector force measurements and setting stringent new upper limits on Yukawa-type interactions in the 5–10 μm range.

Gautam Venugopalan, Clarke A. Hardy, Kenneth Kohn, Yuqi Zhu, Charles P. Blakemore, Alexander Fieguth, Jacqueline Huang, Chengjie Jia, Meimei Liu, Lorenzo Magrini, Nadav Priel, Zhengruilong Wang, Giorgio Gratta2026-04-14⚛️ hep-ex

Non-adiabatic dynamics of eccentric black-hole binaries in post-Newtonian theory

This paper introduces a new set of non-orbit-averaged, gauge-invariant post-Newtonian equations up to 2.5 order that accurately describe the non-adiabatic evolution of eccentric black-hole binaries across all eccentricities, revealing the limitations of traditional orbit-averaged approximations like Peters' equations at the first pericenter passage.

Giulia Fumagalli, Nicholas Loutrel, Davide Gerosa, Matteo Boschini2026-04-14⚛️ gr-qc

Introduction of Vacuum Fields to Cavity with Diffraction Loss

This paper establishes a rigorous quantum optical framework for analyzing diffraction-induced vacuum field injection in DECIGO's Fabry-Perot cavities, demonstrating that while such losses slightly increase radiation pressure noise, cavity detuning combined with homodyne detection and optical-spring locking can effectively mitigate these effects to enhance the detector's sensitivity to primordial gravitational waves.

Kurumi Umemura, Tomohiro Ishikawa, Kenji Tsuji, Shoki Iwaguchi, Yutaro Enomoto, Yuta Michimura, Kentaro Komori, Keiko Kokeyama, Seiji Kawamura2026-04-14🔬 physics.optics

Possible evidences for physics beyond Λ\LambdaCDM from DESI DR2 data

This paper analyzes DESI DR2 data using a model-independent method to present potential evidence for physics beyond the standard Λ\LambdaCDM model, specifically suggesting a temporary acceleration of the universe's expansion at z(0.51,0.955)z \in (0.51, 0.955), a subsequent deceleration at z(0.955,1.484)z \in (0.955, 1.484), and a dark energy equation of state parameter wxw_x less than -1 at z(0.922,0.955)z \in (0.922, 0.955).

Rong-Jia Yang2026-04-14⚛️ gr-qc

Non-relativistic effective theories for fields with general potentials and their implications for cosmology

This paper presents a systematic framework for deriving non-relativistic effective field theories from relativistic theories with generic, potentially non-analytic self-interactions, establishing an effective fluid description and extending the formalism to cosmological settings to analyze ultra-light dark matter models, boson stars, and dark matter halo cores.

H. S. Modirzadeh, R. Moti, M. H. Namjoo2026-04-14⚛️ hep-ph

Comparative Study of Early-Universe Epochs in an f(R,Lm)f(R,L_m) Gravity Model with Effective Curvature--Matter Interaction and Λ\LambdaCDM Cosmology

This paper investigates a specific f(R,Lm)f(R, L_m) gravity model with effective curvature-matter interaction, demonstrating through statistical analysis of distance modulus data and a comparative study of early-Universe epochs that it predicts an earlier onset of structure formation and a higher matter-radiation equality redshift than standard Λ\LambdaCDM cosmology while remaining consistent with observed recombination data.

G. K. Goswami, J. P. Saini2026-04-14⚛️ gr-qc

Comparing astrophysical models to gravitational-wave data in the observable space

This paper advocates for comparing astrophysical population-synthesis models directly to gravitational-wave data in observable space rather than reconstructing the underlying population, demonstrating that this approach respects model validity domains and enables unbiased inference of the observable compact-binary population using LIGO-Virgo-KAGRA data.

Alexandre Toubiana, Davide Gerosa, Matthew Mould, Stefano Rinaldi, Manuel Arca Sedda, Tristan Bruel, Riccardo Buscicchio, Jonathan Gair, Lavinia Paiella, Filippo Santoliquido, Rodrigo Tenorio, Cristiano Ugolini2026-04-14⚛️ gr-qc

On primordial matter production induced by spatial curvature in the early universe

This paper demonstrates that nonvanishing spatial curvature in an initially empty universe generates primordial matter through quantum gravity effects, which is characterized by a stiff equation of state and alters the early universe's expansion history via modified Friedmann equations.

V. E. Kuzmichev (Bogolyubov Institute for Theoretical Physics), V. V. Kuzmichev (Bogolyubov Institute for Theoretical Physics)2026-04-14⚛️ gr-qc

Interacting kk-essence field with non-pressureless Dark Matter: Cosmological Dynamics and Observational Constraints

This paper investigates interacting kk-essence dark energy models with non-pressureless dark matter under two interaction scenarios, demonstrating through autonomous system analysis and extensive observational constraints that these models successfully reproduce cosmological evolution, yield H0H_0 values of 67–70 km/s/Mpc, and remain statistically competitive with the standard Λ\LambdaCDM model.

Saddam Hussain, Qiang Wu, Tao Zhu2026-04-14⚛️ gr-qc

Scattering of massive particles from black holes and naked singularities

This paper presents a numerical study demonstrating that while massive particles scattering off Reissner-Nordström black holes are confined to a narrow range of deflection angles due to an event horizon, those interacting with naked singularities are scattered in all directions by a repulsive core, leading to distinct observable signatures in tidal disruption events.

Angelos Karakonstantakis, Włodek Kluzniak, Maciek Wielgus2026-04-14⚛️ gr-qc