astro-ph.CO papers | Gist.Science

A spinodal decomposition model for the large-scale structure of the universe

This paper proposes a novel thermodynamic framework for cosmic structure formation based on the Cahn-Hilliard model of spinodal decomposition, treating the universe as a binary fluid of matter and dark energy, which successfully reproduces key large-scale structure observables like void fractions and filamentarity while offering a computationally efficient alternative to traditional N-body simulations.

Nitish YadavThu, 12 Ma🔭 astro-ph

Interpretable and physics-informed emulator for the linear matter power spectrum from machine learning

This paper presents an interpretable, physics-informed emulator based on symbolic regression and genetic algorithms that generates compact, closed-form analytic expressions for the linear matter power spectrum in both $\Lambda$ CDM and modified gravity cosmologies, achieving sub-percent accuracy while offering a transparent alternative to traditional black-box emulators for large-scale structure analysis.

J. Bayron Orjuela-Quintana, Domenico Sapone, Savvas NesserisThu, 12 Ma🔭 astro-ph

Blind mitigation of foreground-induced biases on primordial $B$ modes for ground-based CMB experiments

This paper introduces and validates two extensions of the Needlet Internal Linear Combination (NILC) framework—deprojecting foreground moments and marginalizing over residual power via data-driven templates—which effectively eliminate foreground-induced biases in the estimation of the tensor-to-scalar ratio $r$ using Simons Observatory Small Aperture Telescope simulations.

Aliza Mustafa, Alessandro Carones, Nicoletta Krachmalnicoff, Marina Migliaccio, Carlo BaccigalupiThu, 12 Ma🔭 astro-ph

Euclid: The linear-construction covariance and cosmology

This paper validates the linear-construction method for estimating galaxy cluster covariance matrices as a computationally efficient alternative to standard sample covariance, demonstrating that it yields cosmological parameter constraints for $\Omega_{\rm m}$ and $\sigma_8$ that are statistically indistinguishable from those derived using the more expensive sample-covariance approach.

Multi-scale weak lensing detection of galaxy clusters with source redshift tomography

This paper investigates the potential of source redshift tomography to enhance weak lensing galaxy cluster detection using a multi-scale wavelet method, finding that while tomographic combinations do not outperform a single optimal redshift bin due to the accumulation of spurious detections and reduced purity, the approach remains viable despite challenges from large-scale structure contamination and photometric redshift errors.

L. Chappuis, S. Pires, G. W. Pratt, G. Leroy, A. Daurelle, C. Giocoli, C. CarboneThu, 12 Ma🔭 astro-ph

Calibration-independent consistency test of BAO and SNIa data: update

This paper presents a calibration-independent consistency test using Gaussian Processes and the Alcock-Paczynski variable, demonstrating that recent updates to DES SNIa data (DES-Dovekie) resolve previous tensions and confirm consistency across uncalibrated DESI DR2 BAO and multiple SNIa datasets within approximately 1σ.

Bikash R. Dinda, Roy Maartens, Chris ClarksonThu, 12 Ma⚛️ gr-qc

Bulk viscosity from early-time thermalization of cosmic fluids in light of DESI DR2 data

Using DESI DR2 BAO measurements, this paper constrains a model of interacting dark matter and radiation that induces bulk viscosity to resolve cosmic tensions, finding that the data disfavors such interactions prior to recombination and rules out the model as a solution to the Hubble tension.

Hermano Velten, William IaniaThu, 12 Ma⚛️ gr-qc

The analytical general solutions of power-law inflation

This paper revitalizes power-law inflation as a viable cosmological framework by deriving its complete set of general analytical solutions, demonstrating that previous incompatibilities with modern observations arose from considering only a particular solution rather than the full general case.

Yao Yu, Wen-Zhang Feng, Hong-Song Xie, Han Zhang, Bai-Cian KeThu, 12 Ma⚛️ gr-qc

Analytical Emulator for the Baryon Density Distribution inside the Fuzzy Dark Matter Soliton from Machine Learning

This paper develops a machine learning-based analytical emulator to model the baryon density distribution within fuzzy dark matter solitons, successfully reproducing empirical profiles with high accuracy and offering a viable alternative to explicit equations of motion for studying soliton formation and evolution.

Ke Wang, Jianbo Lu, Man Ho ChanThu, 12 Ma⚛️ hep-ph

Effects of dark dipole radiation on eccentric supermassive black hole binary inspirals

This paper investigates how dark dipole radiation from eccentric supermassive black hole binaries can accelerate their inspiral and alter the low-frequency stochastic gravitational-wave background, finding that while it cannot fully resolve the final-parsec problem, it remains detectable through Bayesian analysis of current pulsar timing array data.

Mu-Chun Chen, Yan CaoThu, 12 Ma⚛️ gr-qc

Addressing the Hubble Tension: Insights from Reversible and Irreversible Thermodynamic Processes

This paper investigates cosmological models incorporating reversible and irreversible thermodynamic processes, specifically gravitationally induced matter creation/annihilation and energy exchange with the cosmic horizon, finding that while these thermodynamically motivated interactions do not resolve the Hubble tension when local SH0ES measurements are included, they offer a dynamic dark energy alternative consistent with other cosmological datasets.

Hussain GoharThu, 12 Ma⚛️ gr-qc

New classification method for the dynamical state of galaxy clusters with a Gaussian mixture model

This paper introduces an enhanced, observation-applicable Bayesian classifier using Gaussian mixture models to reliably categorize galaxy cluster dynamical states into multiple merger stages, demonstrating that utilizing a larger set of indicators and projecting high-dimensional simulation data onto lower-dimensional spaces yields superior classification performance compared to previous methods.

Hyowon Kim, Marco Canducci, Rory Smith, Peter Tino, Yara Jaffe, Ho Seong Hwang, Jihye Shin, Kyungwon ChunThu, 12 Ma🔭 astro-ph

Non-minimally coupled scalar field dark sector of the universe: in-depth (Einstein frame) case study

Motivated by recent DESI DR2 results suggesting evolving dark energy, this study analyzes spatially flat FLRW cosmological models with non-minimally coupled scalar fields in the Einstein frame, employing dynamical system methods to examine the evolution and stability of five specific scalar field models under various coupling parameters to understand energy transfer between the scalar sector and matter.

Marcin PostolakThu, 12 Ma⚛️ gr-qc

Cosmological simulation of radio synchrotron bridge between pre-merging galaxy clusters

Using a high-resolution cosmological MHD simulation with improved Lagrangian tracer methods, the authors demonstrate that cosmic ray reacceleration by turbulence induced during the early stages of a galaxy cluster merger can successfully generate a Mpc-sized radio synchrotron bridge that matches the observed properties of the structure between Abell 399 and Abell 401.

Kosuke Nishiwaki, Gianfranco Brunetti, Franco Vazza, Claudio GhellerThu, 12 Ma🔭 astro-ph

Interacting dark sector from intrinsic entropy couplings

This paper introduces a new class of interacting dark sector models where dark matter's intrinsic entropy couples to scalar field dark energy, preserving the standard expansion history while generating distinctive, scale-dependent signatures in cosmological perturbations and structure growth that remain compatible with current observations.

Erik Jensko, Elsa M. Teixeira, Vivian PoulinThu, 12 Ma⚛️ gr-qc

Vector dark matter production during inflation in the gradient-expansion formalism

This paper extends the gradient-expansion formalism to massive vector fields to model their non-linear production during inflation via inflaton couplings, demonstrating that while pure mass coupling enhances only longitudinal modes, the inclusion of kinetic coupling allows transverse modes to dominate or drives the system into a strong backreaction regime depending on the coupling function's behavior.

A. V. Lysenko, O. O. Sobol, S. I. VilchinskiiThu, 12 Ma⚛️ hep-ph

A modern halo streaming model for redshift space distortions

This paper introduces a computationally efficient and physically interpretable halo streaming model for redshift-space distortions that combines a halo-model decomposition with $N$ -body trained emulators to accurately reproduce nonlinear galaxy clustering on small scales, thereby enabling precision cosmological analyses for upcoming surveys like DESI and Euclid.

Cheng-Zong Ruan, Baojiu Li, Carlton M. Baugh, Sownak Bose, Alexander Eggemeier, David F. MotaThu, 12 Ma🔭 astro-ph

Radio selection of heavily obscured AGN in the J1030 field: unraveling a missing Compton-thick population

This study demonstrates that radio selection effectively identifies a previously missed population of heavily obscured, Compton-thick AGNs at high redshifts ( $z>3$ ) in the J1030 field, revealing a number density significantly higher than X-ray-based predictions and highlighting the need for synergistic radio and X-ray observations to fully census these objects.

Giovanni Mazzolari, Roberto Gilli, Marco Mignoli, Marcella Brusa, Isabella Prandoni, Fabio Vito, Ivan Delvecchio, Giorgio Lanzuisi, Alessandro Peca, Andrea Comastri, Stefano Marchesi, Marco Chiaberge, Marisa Brienza, Cristian Vignali, Matilde Signorini, Quirino D'Amato, Fabrizio Gentile, Kazushi Iwasawa, Colin Norman, Alberto Traina, Federica Loiacono, Pietro Baldini, Marianna Annunziatella, Roberto DecarliThu, 12 Ma🔭 astro-ph

Thermal enhancement of inflationary magnetic fields

This paper proposes that assuming a thermal initial state for gauge fields during inflation, rather than the standard vacuum, introduces a dissipative boost that enhances primordial magnetic fields by up to $10^{16}$, suggesting that embedding this mechanism in a warm inflation framework offers a promising path to inflationary magnetogenesis without requiring non-minimal couplings or modified electrodynamics.

Arjun Berera, Suddhasattwa Brahma, Zizang Qiu, Rudnei O. RamosThu, 12 Ma🔭 astro-ph

Measuring neutrino mass in light of ACT DR6 and DESI DR2

This paper presents updated constraints on the total neutrino mass and its hierarchy across various cosmological models using ACT DR6, DESI DR2, and DESY5 data, revealing that while dark energy evolution significantly influences the tightness of upper limits, the inverted hierarchy consistently yields weaker constraints than the degenerate hierarchy.

Lu Feng, Tian-Nuo Li, Guo-Hong Du, Jing-Fei Zhang, Xin ZhangThu, 12 Ma⚛️ hep-ph

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