Tootfinder

The Filament Rift: $\Lambda$CDM's Structural Challenge Against Observation
Saeed Tavasoli, Parsa Ghafour
https://arxiv.org/abs/2508.07480 https://arxiv…

The Filament Rift: $Λ$CDM's Structural Challenge Against Observation
This study presents the first extended comparison of cosmic filaments identified in SDSS DR10 observations ($z < 0.05$) and the IllustrisTNG300-1 $Λ$CDM simulation ($z = 0$), utilizing the novel GrAviPaSt filament-finder method. The analyses are performed on both macro- and micro-filaments, each characterized by their length, thickness, and contrast in mass density. In addition to total sample comparisons, two subcategories of micro-filaments, GG (linking galaxy groups) and CC (linking galaxy …

Topological defects as effective dynamical dark energy
Haipeng An, Chengcheng Han, Borui Zhang
https://arxiv.org/abs/2506.10075 https://

Topological defects as effective dynamical dark energy
In this work, we consider the possibility that the dynamical dark energy hinted at by recent DESI data may be mimicked by the effects of additional components in the universe, potentially arising from topological defects. We find that the data does not show a particular preference for the existence of cosmic strings. However, a domain wall contribution at the percent level can improve the fit, yielding a $Δχ^2= -1.72$ compared to the $Λ\rm{CDM}$ model. The improvement indicates that topologi…

On the Reliability of Quasars as Cosmological Distance Indicators
Ariadna Montiel, Sofia Samario-Nava, Juan Carlos Hidalgo, Jose Ignacio Cabrera
https://arxiv.org/abs/2509.08983

On the Reliability of Quasars as Cosmological Distance Indicators
The goal of the present paper is to assess the usefulness of quasars as cosmological distance indicators. We calibrate, in a model-independent way, the non-linear relation between X-ray and UV emission to derive quasar luminosity distances. Using this calibration, we construct the Hubble diagram up to redshift $z \sim 7.5$, and test the ability of quasars to constrain the $Λ$CDM and $ω$CDM models at low and high redshifts, in combination with the Type Ia supernova Pantheon Plus sample, as wel…

Soundtoys 5.5 update, free window resizing, everything explained
https://cdm.link/soundtoys-5-5-update-free-window-resizing-everything-explained/?utm_source=flipboard&utm_conten…

Soundtoys 5.5 update, free window resizing, everything explained - CDM Create Digital Music
Soundtoys is here with the 5.5 upgrade of their flagship suite, plus a free update for everyone with resizable UIs. Here's a breakdown of what's new, what's free, what's paid, and more. And there's a sale on, too.

Growth Rate Analysis in $f(R,L_m)$ Gravity: A Comparative Study with \boldmath$\Lambda$CDM Cosmology
G. K. Goswami, J. P. Saini
https://arxiv.org/abs/2507.04079

Growth Rate Analysis in $f(R,L_m)$ Gravity: A Comparative Study with \boldmath$Λ$CDM Cosmology
We investigate the evolution of cosmic structures within the framework of modified gravity, specifically focusing on theories described by the function $f(R, L_m)$, where $R$ is the Ricci scalar and $L_m$ is the matter Lagrangian. This class of models introduces a non-minimal coupling between geometry and matter, leading to modifications in the dynamics of density perturbations. We derive the linear growth equation and compute the observable growth rate $fσ_8(z)$, which is directly accessible …

An Agentic Model Context Protocol Framework for Medical Concept Standardization
Jaerong Ahn, Andrew Wen, Nan Wang, Heling Jia, Zhiyi Yue, Sunyang Fu, Hongfang Liu
https://arxiv.org/abs/2509.03828

An Agentic Model Context Protocol Framework for Medical Concept Standardization
The Observational Medical Outcomes Partnership (OMOP) common data model (CDM) provides a standardized representation of heterogeneous health data to support large-scale, multi-institutional research. One critical step in data standardization using OMOP CDM is the mapping of source medical terms to OMOP standard concepts, a procedure that is resource-intensive and error-prone. While large language models (LLMs) have the potential to facilitate this process, their tendency toward hallucination ma…

Constraining $\Lambda$CDM, $\omega$CDM, and $\omega_0\omega_a$CDM models with DESI DR2 BAO: Redshift-Resolved Diagnostics and the Role of $r_d$
Seokcheon Lee
https://arxiv.org/abs/2507.01380

Constraining $Λ$CDM, $ω$CDM, and $ω_0ω_a$CDM models with DESI DR2 BAO: Redshift-Resolved Diagnostics and the Role of $r_d$
We present a detailed comparison of $Λ$CDM, $ω$CDM, and $ω_0ω_a$CDM cosmologies using the latest redshift-resolved BAO measurements from DESI DR2. By separating $r_d$-dependent and $r_d$-independent observables and applying both fixed and model-derived sound horizon values, we test the consistency of each model across 24 observables spanning redshift 0.2 to 2.3. Our results show that the $ω$CDM model is statistically favored over $Λ$CDM, with lower $χ^2$, AIC, and BIC values and reduced…

Trump tariffs bring chaos, as shipments halted from Europe, Asia https://cdm.link/trump-de-minimis-chaos/

Trump tariffs bring chaos, as shipments halted from Europe, Asia - CDM Create Digital Music
The Trump administration's trade policies do more than increase costs for US consumers. Their historic scale and disorganized rollout are causing global disruptions. That hurts independent music gear makers and label owners. It's also ironically likely to cripple manufacturers trying to work in the USA. The only (sort of) good news: shippers and exporters are trying to find solutions, and at least some of the disruptions should be temporary. But those solutions won't come free.

Matter power spectrum reconstruction with KiDS-Legacy: Improved internal $\Lambda$CDM consistency and preference for strong baryonic feedback
Jeger C. Broxterman, Patrick Simon, Lucas Porth, Konrad Kuijken, Angus H. Wright, Marika Asgari, Maciej Bilicki, Catherine Heymans, Hendrik Hildebrandt, Henk Hoekstra, Benjamin Joachimi, Shun-Sheng Li, Matteo Maturi, Lauro Moscardini, Mario Radovich, Robert Reischke, Maximilian Von Wietersheim-Kramsta

Matter power spectrum reconstruction with KiDS-Legacy: Improved internal $Λ$CDM consistency and preference for strong baryonic feedback
Direct measurements of the matter power spectrum, $P_\mathrm{m}(k,z)$, provide a powerful tool to investigate observed tensions between models of structure growth while also testing the internal consistency of cosmological probes. We analyse cosmic shear data from the final data release of the Kilo-Degree Survey (KiDS), presenting a deprojected $P_\mathrm{m}(k,z)$, measured in up to three redshift bins. Compared to analyses using previous KiDS releases, we find improved internal consistency in …

An Interpretable AI Framework to Disentangle Self-Interacting and Cold Dark Matter in Galaxy Clusters: The CKAN Approach
Zhenyang Huang, Haihao Shi, Zhiyong Liu, Na Wang
https://arxiv.org/abs/2509.06788

An Interpretable AI Framework to Disentangle Self-Interacting and Cold Dark Matter in Galaxy Clusters: The CKAN Approach
Convolutional neural networks have shown their ability to differentiate between self-interacting dark matter (SIDM) and cold dark matter (CDM) on galaxy cluster scales. However, their large parameter counts and ''black-box'' nature make it difficult to assess whether their decisions adhere to physical principles. To address this issue, we have built a Convolutional Kolmogorov-Arnold Network (CKAN) that reduces parameter count and enhances interpretability, and propose a novel analytical framewo…

Reionization optical depth and CMB-BAO tension in punctuated inflation
Zhiqi Huang
https://arxiv.org/abs/2509.09086 https://arxiv.org/pdf/2509.09086…

Reionization optical depth and CMB-BAO tension in punctuated inflation
Within the standard six-parameter Lambda cold dark matter ($Λ$CDM) model, a $2$-$3σ$ tension persists between baryon acoustic oscillation (BAO) measurements from the Dark Energy Spectroscopic Instrument (DESI) and observations of the cosmic microwave background (CMB). Although this tension has often been interpreted as evidence for dynamical dark energy or a sum of neutrino masses below the established minimum, recent studies suggest it may instead originate from an underestimation of the rei…

Cosmology inference with perturbative forward modeling at the field level: a comparison with joint power spectrum and bispectrum analyses
Kazuyuki Akitsu, Marko Simonovi\'c, Shi-Fan Chen, Giovanni Cabass, Matias Zaldarriaga
https://arxiv.org/abs/2509.09673

Cosmology inference with perturbative forward modeling at the field level: a comparison with joint power spectrum and bispectrum analyses
We extend field-level inference to jointly constrain the cosmological parameters $\{A,ω_{\rm cdm},H_0\}$, in both real and redshift space. Our analyses are based on mock data generated using a perturbative forward model, with noise drawn from a Gaussian distribution with a constant power spectrum. This idealized setting, where the field-level likelihood is exactly Gaussian, allows us to precisely quantify the information content in the nonlinear field on large scales. We find that field-level …

Far beyond the Lounge, with Lounge Lizard EP-5’s new physical modeling
#MusicianTips #MusicTech

Far beyond the Lounge, with Lounge Lizard EP-5's new physical modeling - CDM Create Digital Music
AAS' Lounge Lizard EP-5 refreshes one of the definitive electric keyboards in software with a redesigned physical modeling core for tine and reed instruments. What sets this particular plug-in apart is deep modeling and diverse presets, which can take the instrument way beyond the lounge. Yes, it can be an accurate electric keyboard, but it can also imagine new keyboard instrument sounds that you've never heard before.

Challenging $\Lambda$CDM with Higher-Order GUP Corrections
Andronikos Paliathanasis, Genly Leon, Yoelsy Leyva, Giuseppe Gaetano Luciano, Amare Abebe
https://arxiv.org/abs/2508.20644

Challenging $Λ$CDM with Higher-Order GUP Corrections
We study quantum corrections to the $Λ$CDM model model arising from a minimum measurable length in Heisenberg's uncertainty principle. We focus on a higher-order Generalized Uncertainty Principle, beyond the quadratic form. This generalized GUP introduces two free parameters, and we determine the modified Friedmann equation. This framework leads to a perturbative cosmological model that naturally reduces to $Λ$CDM in an appropriate limiting case of the deformation parameters. We construct the…

Charged Particle Oscillations around a Black Hole Surrounded by CDM Halos
Zakaria Ahal, Hasan El Moumni, Karima Masmar
https://arxiv.org/abs/2507.11139 htt…

Charged Particle Oscillations around a Black Hole Surrounded by CDM Halos
HF QPOs are among the most intriguing phenomena observed in LMXBs containing BHs or neutron stars. In this work, we investigate charged particles' dynamics in the nearby of a Schwarzschild-like BH embedded in a uniform magnetic field and surrounded on all sides by CDM. Thereby gaining deeper insight into the influence of magnetic and DM distributions on observable phenomena near compact objects. We first present a modified metric, which incorporates the effects of a CDM ... We compute the fun…

Evolution of linear matter perturbations with error-bounded bundle physics-informed neural networks
Luca Gomez Bachar, Augusto T. Chantada, Susana J. Landau, Claudia G. Sc\'occola, Pavlos Protopapas
https://arxiv.org/abs/2508.08443

Evolution of linear matter perturbations with error-bounded bundle physics-informed neural networks
We consider the evolution of linear matter perturbations in the context of the standard cosmological model ($Λ$CDM) and a phenomenological modified gravity model. We use the physics-informed neural network (PINN) bundle method, which allows to integrate differential systems as an alternative to the traditional numerical method. We apply the PINN bundle method to the equation that describes the matter perturbation evolution, to compare its outcomes with recent data on structure growth, $fσ_8$.…

Listen to 8 hours of sound dedicated to Palestine - and act -
#DoingGood #EndGenocide
https://

Listen to 8 hours of sound dedicated to Palestine - and act - CDM Create Digital Music
Music and sound are not action -- at least, not normally. But sound can recenter you, rewire your brain, and let you catch your breath before that action. So I find myself returning to this eight-hour broadcast by London's Sister Midnight FM, which includes Palestinian artists who have long been featured on CDM, including Muqata'a, bint mbareh, and Dakn.

#COZMIC - Cosmological Zoom-in Simulations with Initial Conditions Beyond Cold Dark Matter / Cosmological Zoom-in Simulations with Fractional non-CDM Initial Conditions / Cosmological Zoom-in Simulations of Self-interacting Dark Matter with Suppressed Initial Conditions: https://iopscience.iop.org/article/10.3847/1538-4357/adceef / https://iopscience.iop.org/article/10.3847/1538-4357/adce83 / https://iopscience.iop.org/article/10.3847/1538-4357/adce82 -> Scientists code Milky Way twin galaxies to better understand dark matter: https://today.usc.edu/scientists-code-milky-way-twin-galaxies-to-better-understand-dark-matter - USC researchers led the development of a computer simulation that gives astrophysicists a mechanism for testing ideas about dark matter and its behavior in the Milky Way and other galaxies.

Laser-Driven Annular Shock Waves as Laboratory Analogues of $w$CDM Cosmologies and Cosmological Gravitational Waves
Felipe A. Asenjo, Felipe Veloso, Julio C. Valenzuela
https://arxiv.org/abs/2506.15493

Laser-Driven Annular Shock Waves as Laboratory Analogues of $w$CDM Cosmologies and Cosmological Gravitational Waves
We demonstrate that the experimental evolution of an annular, laser-driven plasma shock wave, expanding over time and undergoing self-interaction gives rise to multiple shock structures that evolve analogously to a multicomponent cosmological universe. Different propagation trajectories along the shock surface correspond to various forms of $w$CDM cosmologies, enabling the study of scenarios ranging from simple radiation- or matter-dominated universes to those including dark energy. We further …

Hierarchical assembly impedes the inference of stellar mass growth histories for individual galaxies
R. K. Cochrane
https://arxiv.org/abs/2509.02700 https://

Hierarchical assembly impedes the inference of stellar mass growth histories for individual galaxies
Some massive, quiescent galaxies at z>3 appear to contain considerable numbers of old stars (forming at z>7). Works inferring the star formation histories of at least one such galaxy observed with JWST have suggested that the assembly of so much stellar mass so early may challenge the well-established Cold Dark Matter (CDM) cosmological framework, or else indicate extraordinarily high past star formation efficiencies. However, these studies implicitly assume that all the stars in place at the e…

A simple ghost free and caustic free mimetic scalar field dark matter model
Emmanuel Kanambaye
https://arxiv.org/abs/2507.05290 https://

A simple ghost free and caustic free mimetic scalar field dark matter model
Chamseddine and Mukhanov have promoted the concept of mimetic dark matter as alternative dark matter candidate coming from gravitation. Unfortunately although being very interesting, their proposition turned out to have weakness among which ghost and caustic instabilities. In this paper I propose among the simplest ghost free and caustic free scalar field dark matter extension of their model; a proposition capable of challenging $Λ$CDM model or even capable of doing better.

RIP, Mark Snow: listen to the composer talk about scoring X-Files and more
https://cdm.link/rip-mark-snow/?utm_source=flipboard&utm_content=muz4now/magazine/music

RIP, Mark Snow: listen to the composer talk about scoring X-Files and more - CDM Create Digital Music
Mark Snow, the mind-bogglingly prolific composer behind scores for Blue Bloods, Smallville, and the X-Files has died at age 78. From TV to film to games, Snow's take on electronic music scoring has left a mark on many of us. Here he is talking about his take on music, and some reflections on that unforgettable X-Files score.

Braneworld Dark Energy in light of DESI DR2
Swagat S. Mishra, William L. Matthewson, Varun Sahni, Arman Shafieloo, Yuri Shtanov
https://arxiv.org/abs/2507.07193

Braneworld Dark Energy in light of DESI DR2
Recent observational results from the DESI collaboration reveal tensions with the standard $Λ$CDM model and favor a scenario in which dark energy (DE) decays over time. The DESI DR2 data also suggest that the DE equation of state (EoS) may have been phantom-like ($w < - 1$) in the past, evolving to $w > - 1$ at present, implying a recent crossing of the phantom divide at $w = - 1$. Scalar field models of DE naturally emerge in ultraviolet-complete theories such as string theory, which is typic…

Constraints on Dark Matter Models from Supermassive Black Hole Evolution
John Ellis, Malcolm Fairbairn, Juan Urrutia, Ville Vaskonen
https://arxiv.org/abs/2509.06955 https://

Constraints on Dark Matter Models from Supermassive Black Hole Evolution
A semi-analytical model for the evolution of galaxies and supermassive black holes (SMBHs) within the $Λ$CDM paradigm has been shown to yield stellar mass-BH mass relations that reproduce both the JWST and pre-JWST observations. Either fuzzy or warm dark matter (FDM or WDM) would suppress the formation of the smaller galactic halos that play important roles in the CDM fit to the high-redshift SMBH data. Our analysis of the stellar mass-BH mass relation disfavours FDM fields with masses $< 2.0\…

Dynamical dark energy in models close to $\Lambda$CDM
Saikat Chakraborty, Charlotte Louw, Peter K. S. Dunsby, Kelly MacDevette, Alvaro de la Cruz Dombriz
https://arxiv.org/abs/2508.09813

Dynamical dark energy in models close to $Λ$CDM
In this communication we address whether or not there is an equivalence between the kinematical and dynamical descriptions of the spatially flat $Λ$CDM model. We address this by investigating whether an almost $Λ$CDM expansion history ($j(z)\approx1$) corresponds to an almost $Λ$CDM model ($w_{\rm DE}(z)\approx-1$) by considering two particular explicit examples. At least for the cases considered, this turns out not to be the case. Instead, what we find is that an almost $Λ$CDM cosmic evolu…

Can dynamic dark energy explain the $S_8$ tension, the `lensing is low' effect, or strong baryon feedback?
S. Heydenreich, A. Leauthaud, J. DeRose
https://arxiv.org/abs/2508.05746

Can dynamic dark energy explain the $S_8$ tension, the `lensing is low' effect, or strong baryon feedback?
We investigate the impact of a DESI motivated dynamic dark energy cosmology on three cosmological anomalies, the $S_8$ tension, the `lensing is low' effect, and observations of strong baryonic feedback. We analyze how these observations vary in $Λ$CDM versus dynamic dark energy. We find that the galaxy-galaxy lensing signal is reduced by up to 7% with respect to galaxy clustering and that cosmic shear is suppressed by 14%. These differences are primarily caused by changes to cosmological dista…

Ten-dimensional neural network emulator for the nonlinear matter power spectrum
Yanhui Yang, Simeon Bird, Ming-Feng Ho, Mahdi Qezlou
https://arxiv.org/abs/2507.07177

Ten-dimensional neural network emulator for the nonlinear matter power spectrum
We present GokuNEmu, a ten-dimensional neural network emulator for the nonlinear matter power spectrum, designed to support next-generation cosmological analyses. Built on the Goku $N$-body simulation suite and the T2N-MusE emulation framework, GokuNEmu predicts the matter power spectrum with $\sim 0.5 \%$ average accuracy for redshifts $0 \leq z \leq 3$ and scales $0.006 \leq k/(h\,\mathrm{Mpc}^{-1}) \leq 10$. The emulator models a 10D parameter space that extends beyond $Λ$CDM to include dyn…

Alleviating the $H_0$ tension in Rastall gravity
R. Mohebi, Kh. Saaidi T. Golanbari, K. Karami
https://arxiv.org/abs/2508.20129 https://arxiv.org/pdf/2508.…

Alleviating the $H_0$ tension in Rastall gravity
The tension between measurements of the Hubble constant $H_0$ locally and the value inferred from Planck satellite have provided a strong motivation to explore theoretical frameworks beyond the standard cosmological model ($Λ$CDM). To this aim, we investigate the $H_0$ tension in the Rastall $Λ$CDM model (R-$Λ$CDM), formulated within the Rastall gravity framework as a phenomenological extension of General Relativity featuring a non-conserved energy-momentum tensor. To constrain the cosmologi…

High-redshift Galaxies from JWST Observations in More Realistic Dark Matter Halo Models
Saeed Fakhry, Reyhaneh Vojoudi Salmani, Javad T. Firouzjaee
https://arxiv.org/abs/2507.23742

High-redshift Galaxies from JWST Observations in More Realistic Dark Matter Halo Models
The James Webb Space Telescope (JWST) has unveiled unexpectedly massive galaxy candidates at high redshifts, challenging standard $Λ$CDM cosmological predictions. In this work, we study the predictions of more realistic dark matter halo models combined with modified matter power spectra for interpreting JWST observations of high-redshift galaxies. We employ three halo mass functions: the conventional Sheth-Tormen (ST) model and two physically motivated alternatives introduced by Del Popolo (DP…

A dynamical systems perspective on the thermodynamics of late-time cosmology
Dipayan Mukherjee, Harkirat Singh Sahota, Swati Gavas
https://arxiv.org/abs/2509.04964 https://

A dynamical systems perspective on the thermodynamics of late-time cosmology
A thermodynamic description of cosmological spacetimes may provide insights into the fundamentals of the cosmic evolution that remain otherwise obscure, in close analogy with 'black hole thermodynamics'. We investigate the thermodynamic properties of late-time cosmological evolution using the dynamical systems approach, focusing on the $Λ$CDM model and quintessence models with an exponential potential. Thermodynamic quantities obtained through the Hayward-Kodama formalism are mapped onto the p…

Is $\omega_0 \omega_a$CDM a good model for the clumpy Universe?
Fernanda Oliveira, Felipe Avila, Camila Franco, Armando Bernui
https://arxiv.org/abs/2507.00779

Is $ω_0 ω_a$CDM a good model for the clumpy Universe?
The DESI collaboration just obtained a set of precise BAO measurements, that combined with CMB and SNIa datasets show that the $ω_0 ω_a$CDM model is preferred over $Λ$CDM, at more than $4\,σ$, to describe the dynamics of the expanding Universe. This raises the question whether this model also suitably describes the clumpy Universe. Also lately, detailed analyses of diverse cosmic tracers resulted in a new dataset of measurements of an observable from the clumpy Universe: $σ_8(z)$, spanning…

Resolving the Planck-DESI tension by non-minimally coupled quintessence
Jia-Qi Wang, Rong-Gen Cai, Zong-Kuan Guo, Shao-Jiang Wang
https://arxiv.org/abs/2508.01759 https://

Resolving the Planck-DESI tension by non-minimally coupled quintessence
The Planck measurement of the cosmic microwave background (CMB) has established the $Λ$-cold-dark-matter ($Λ$CDM) model as the concordant model along with other observations. However, recent measurements of baryon acoustic oscillations (BAO) from the Dark Energy Spectroscopic Instrument (DESI) collaboration have renewed the matter fraction $Ω_\mathrm{m}$ tension between DESI-$Λ$CDM and Planck-$Λ$CDM. Directly reconciling this CMB-BAO tension with a dynamical DE in Chevallier-Polarski-Linde…

Topological dark energy from spacetime foam: A challenge for $\Lambda$CDM
Fotios K. Anagnostopoulos, Stylianos A. Tsilioukas, Emmanuel N. Saridakis
https://arxiv.org/abs/2507.18389

Topological dark energy from spacetime foam: A challenge for $Λ$CDM
Using only the standard considerations of spacetime foam and the Euclidean Quantum Gravity techniques known long ago, we result to a model of Topological Dark Energy (TDE) that outperforms the standard $Λ$CDM paradigm with regard to data fitting efficiency. Specifically, it is known that at the foam level, topologically non-trivial solutions such as instantons appear. In the particular case of Einstein-Gauss-Bonnet gravity, we obtain an effective dynamical dark energy term proportional to the …

Is this the fall of the $\Lambda$CDM throne? Evidence for dynamical dark energy rising from combinations of different types of datasets
Mustapha Ishak, Leonel Medina-Varela
https://arxiv.org/abs/2507.22856

Is this the fall of the $Λ$CDM throne? Evidence for dynamical dark energy rising from combinations of different types of datasets
We derive multiple constraints on dark energy and compare dynamical dark energy models with a time-varying equation of state ($w_0 w_a$CDM) versus a cosmological constant model ($Λ$CDM). We use Baryon Acoustic Oscillation (BAO) from DESI and DES, Cosmic Microwave Background (Planck) with and without lensing from Planck and ACT (noted CMB and CMBL, respectively), supernova (SN), and cross-correlations between galaxy positions and galaxy lensing from DES. First, we use pairs or trios of datasets…

Beyond Extreme Burstiness: Evolving Star Formation Efficiency as the Key to Early Galaxy Abundance
Abhijnan Kar, Shadab Alam, Joseph Silk
https://arxiv.org/abs/2507.20606 https:…

Beyond Extreme Burstiness: Evolving Star Formation Efficiency as the Key to Early Galaxy Abundance
JWST observations have revealed an overabundance of bright galaxies at $z \geq 9$, creating apparent tensions with theoretical predictions within standard $Λ$CDM cosmology. We address this challenge using a semi-empirical approach that connects dark matter halos to observed UV luminosity through physically motivated double power-law star formation efficiency (SFE) model as a function of halo mass, redshift and perform joint Bayesian analysis of luminosity functions spanning $z = 4 - 16$ using …

Does DESI DR2 challenge $\Lambda$CDM paradigm ?
Himanshu Chaudhary, Salvatore Capozziello, Vipin Kumar Sharma, Ghulam Mustafa
https://arxiv.org/abs/2507.21607 https://

Does DESI DR2 challenge $Λ$CDM paradigm ?
Although the debate about the systematic errors of DESI DR1 is still open, recent DESI DR2 is consistent with DESI DR1 and further strengthens the results of DESI DR1. In this analysis, we present a $\sim 2.38 σ$ discrepancy between Planck $Λ$ CDM cosmology and the DESI DR2 Luminous Red Galaxy (LRG1) data at $z_{\text{eff}} = 0.51$, which predicts an unexpectedly large value for $Ω_m$, $Ω_m = 0.471^{+0.119}_{-0.065}$. We find that the $w_0 w_a$CDM model, using DESI DR2 data, suggests $w_0 >…

Euclid: Forecasts on $\Lambda$CDM consistency tests with growth rate data
I. Ocampo, D. Sapone, S. Nesseris, G. Alestas, J. Garc\'ia-Bellido, Z. Sakr, C. J. A. P. Martins, J. P. Mimoso, A. Carvalho, A. Da Silva, A. Blanchard, S. Casas, S. Camera, M. Martinelli, V. Pettorino, A. Amara, S. Andreon, N. Auricchio, C. Baccigalupi, M. Baldi, A. Balestra, S. Bardelli, P. Battaglia, F. Bernardeau, A. Biviano, E. Branchini, M. Brescia, G. Ca\~nas-Herrera, V. Capobianco, C. Carbone, V. F. Ca…

Euclid: Forecasts on $Λ$CDM consistency tests with growth rate data
The large-scale structure (LSS) of the Universe is an important probe for deviations from the canonical cosmological constant $Λ$ and cold dark matter ($Λ$CDM) model. A statistically significant detection of any deviations would signify the presence of new physics or the breakdown of any number of the underlying assumptions of the standard cosmological model or possible systematic errors in the data. In this paper, we quantify the ability of the LSS data products of the spectroscopic survey o…

Uncertainty-Aware Neural Networks for Fuzzy Dark Matter Model Selection from \texorpdfstring{$x_{\rm HI}$}{x_HI} Measurements
Bahareh Soleimanpour Salmasi, S. Mobina Hosseini
https://arxiv.org/abs/2509.05551

Uncertainty-Aware Neural Networks for Fuzzy Dark Matter Model Selection from \texorpdfstring{$x_{\rm HI}$}{x_HI} Measurements
The nature of dark matter remains a central question in cosmology, with fuzzy dark matter (FDM) models offering a compelling alternative to the cold dark matter (CDM) paradigm. We explore FDM scenarios by performing 21-cm simulations across a parameter space with \texorpdfstring{$f_{\rm FDM} \in [0.02, 0.10]$}{f_FDM in [0.02, 0.10]} and \texorpdfstring{$m_{\rm FDM} \in [10^{-24}, 10^{-21}]\,\mathrm{eV}$}{m_FDM in [10^-24, 10^-21] eV}, obtaining global neutral hydrogen fractions (\texorpdfstring…

Constraining parameters of spinor field dark energy: An alternative to $\Lambda$CDM model under the spherically symmetric FLRW space-time
Bijan Saha, Mahendra Goray
https://arxiv.org/abs/2506.16323

Constraining parameters of spinor field dark energy: An alternative to $Λ$CDM model under the spherically symmetric FLRW space-time
This study constrains the cosmological parameters within the scope of a spherically symmetric FLRW cosmological model, the role of a nonlinear spinor field in the universe's evolution. To test this approach, we incorporate the recent Cosmic chronometers, Supernova, and Sloan Digital Sky Survey data. It is found that if spherical coordinates give the FLRW model, the energy-momentum tensor (EMT) of the spinor field possesses nontrivial non-diagonal components. These non-diagonal components of EMT…

A Promise for the JWST era: Massive black holes directly collapsed from wave dark matter haloes, and Star formation in and around their accretion flows
Xiaobo Dong, Yongda Zhu, Marcia Rieke, George Rieke, Xinyu Li, Peter Behroozi, Haixia Ma, Runyu Meng, Zhiying Mao, Zhe Sun
https://arxiv.org/abs/2508.09258

A Promise for the JWST era: Massive black holes directly collapsed from wave dark matter haloes, and Star formation in and around their accretion flows
There are several puzzling phenomena from recent JWST observations, which seem to push the standard ΛCDM cosmology over the edge. All those puzzles can be understood in a coherent way if we assume that first massive black holes (MBHs, the "heavy eggs") formed by directly collapsing from wave CDM haloes, which can be even earlier than the formation of first galaxies (the "chickens"). We elucidate two false obstacles that have been believed to prevent wave CDM haloes from collapsing into black h…

Comment on "Dynamical Dark Energy at Late Time $\Lambda$CDM"
James M. Cline
https://arxiv.org/abs/2507.21278 https://arxiv.org/pdf/2507.21278

Comment on "Dynamical Dark Energy at Late Time $Λ$CDM"
In arXiv:2505.18900 it was claimed that an apparent evolution of the dark energy equation of state occurs within the standard $Λ$CDM cosmological model. I point out that this erroneous conclusion is due to a mathematical error.

Cosmological perturbations for smooth sign-switching dark energy models
Mariam Bouhmadi-L\'opez, Be\~nat Ibarra-Uriondo
https://arxiv.org/abs/2506.18992

Cosmological perturbations for smooth sign-switching dark energy models
In this work, we carry out a comprehensive perturbative analysis of four cosmological models featuring a sign-switching cosmological constant. Among these, we include the well-known $Λ_{\rm s}$CDM model, characterised by an abrupt transition from a negative to a positive cosmological constant. We also consider the L$Λ$CDM model, which exhibits a generalised ladder-step evolution, as well as the SSCDM and ECDM models, both of which undergo a smooth sign change at comparable redshifts. We solve…

Looking beyond lambda
Alexie Leauthaud, Adam Riess
https://arxiv.org/abs/2509.00359 https://arxiv.org/pdf/2509.00359

Looking beyond lambda
Widening cracks are appearing in the $Λ$CDM model and it is becoming increasingly clear that the standard cosmological model struggles to describe the full expansion history of the Universe as revealed by the Cosmic Microwave Background, Baryon Acoustic Oscillation measurements, and locally calibrated Type Ia supernovae. Taken at face value, recent results suggest a dark sector that may be more complex than commonly assumed. We must prepare for the possibility of moving beyond the $Λ$CDM era,…

Quantum stress-energy at timelike boundaries: testing a new beyond-$\Lambda$CDM parameter with cosmological data
Oliver H. E. Philcox, Eva Silverstein, Gonzalo Torroba
https://arxiv.org/abs/2507.00115

Quantum stress-energy at timelike boundaries: testing a new beyond-$Λ$CDM parameter with cosmological data
We analyze the basic cosmological effects of a population of timelike boundaries -- a form of nontrivial spacetime topology -- containing a boundary layer of quantum stress energy. This accumulation of vacuum fluctuations of quantum fields can be consistently negative and UV sensitive, providing an additional source of cosmic energy density strong enough to compete with matter and dark energy. For boundary conditions enabling a solution with fixed comoving boundary size, this effect contributes…

Constraints on transition redshift utilizing the latest H(z) measurements and comments on the Hubble tension
Jianping Hu, Xuandong Jia, DaoHong Gao, Jiaze Gao, Baoquan Gao, Fayin Wang
https://arxiv.org/abs/2508.05389

Constraints on transition redshift utilizing the latest H(z) measurements and comments on the Hubble tension
The motivation of this paper is to obtain reliable constraints of transition redshift ($z_{ztr}$) and, in combination with the evolution of the Hubble constant ($H_{0}$) that could alleviate the Hubble tension, discuss the possible origin of the tension. Utilizing the latest H(z) measurements and different methods ($Λ$CDM model, Cosmography, and Gaussian process method), we investigated the impact of methodology and dataset on $z_{ztr}$ constraints, and find that the choice of method has a gre…

Bimetric gravity improves the fit to DESI BAO and eases the Hubble tension
Marcus H\"og{\aa}s, Edvard M\"ortsell
https://arxiv.org/abs/2507.03743

Bimetric gravity improves the fit to DESI BAO and eases the Hubble tension
We investigate whether the latest combination of DESI DR2 baryon acoustic oscillation (BAO) measurements, cosmic microwave background (CMB) data (Planck 2018 + ACT), and Type Ia supernovae (SNe Ia) compilations (Pantheon+, Union3, and DES Y5) favor a dynamical dark energy component, and explore if such a scenario can simultaneously help resolve the Hubble tension. We contrast two frameworks: the widely used phenomenological $w_0 w_a$CDM model, and bimetric gravity, a fundamental modification of…

Cosmological effect of coherent oscillation of ultralight scalar fields in a multicomponent universe
Priyanka Saha, Dipanjan Dey, Kaushik Bhattacharya
https://arxiv.org/abs/2506.12863

Cosmological effect of coherent oscillation of ultralight scalar fields in a multicomponent universe
The idea that coherent oscillations of a scalar field, oscillating over a time period that is much shorter than the cosmological timescale, can exhibit cold dark matter (CDM) like behavior was previously established. In our work we first show that this equivalence between the oscillating scalar field model and the CDM sector is exact only in a flat Friedmann-Lemaitre-Robertson-Walker (FLRW) spacetime in the absence of cosmological constant and any other possible matter components in the univers…

Comparison of $R_h=ct$ and $\Lambda$CDM using DESI DR1 measurements
Kunj Panchal, Shantanu Desai
https://arxiv.org/abs/2506.18445 https://

Comparison of $R_h=ct$ and $Λ$CDM using DESI DR1 measurements
We use DESI DR1 BAO measurements of the ratio of tranvserse comoving distance to Hubble distance in order to test the compatibility of $R_h=ct$ over flat $Λ$CDM. For this purpose, we used Bayesian model selection to evaluate the efficacy of these models given the observed data. When we consider the BAO measurements up to redshift of 1.3, both models are equally favored. However, when we consider the Lyman-$α$ QSO measurement at redshift of 2.33, we find Bayes factors of greater than 100 for f…

Probing the Type 3 interacting dark-energy model using matter pairwise velocity
Kin Ho Luo, Ming-chung Chu, Wangzheng Zhang
https://arxiv.org/abs/2508.04312 https://

Probing the Type 3 interacting dark-energy model using matter pairwise velocity
Dark sector interactions can be explored via the so-called Type 3 model where dark matter and dark energy exchange momentum only, so as to minimize deviations from the $Λ$CDM background expansion history. Using N-body simulations, we analyze the imprint of Type 3 model parameters, the momentum exchange coupling constant $β$ and the slope of scalar field potential $λ$, on large-scale structure (LSS) observables, particularly the matter pairwise velocity statistics. We find that the effects of…

Stability Analysis of Four $f(Q)$ Gravity Models : A Cosmological Review in the Background of Bianchi-I Anisotropy
Subhajit Pal, Atanu Mukherjee, Ritabrata Biswas, Farook Rahaman
https://arxiv.org/abs/2506.21715

Stability Analysis of Four $f(Q)$ Gravity Models : A Cosmological Review in the Background of Bianchi-I Anisotropy
With the non-metricity scalar $Q$ as the functional argument, several $f(Q)$ gravity models is found to be proposed which are perfectly able to mimic the late time accelerated expansion as pointed out by the type Ia supernovae observations. Temperature fluctuation differences for two celestial hemispheres, Hubble tension, voids, dipole modulation, anisotropic inflation etc motivates us to think beyond the $Λ$CDM model and cosmological principle. Bianchi-I model portrays anisotropic universe im…

Revisiting $\Lambda$CDM extensions in light of re-analyzed CMB data
Jacobo Asorey, Javier de Cruz P\'erez
https://arxiv.org/abs/2506.13537 https://

Revisiting $Λ$CDM extensions in light of re-analyzed CMB data
In the last years with the increasing precision in cosmological observations we have been able to establish an standard model of cosmology, the so-called $Λ$CDM, but also find some tensions between cosmological probes that are difficult to explain within the context of this model. We tested several phenomenological extensions of the $Λ$CDM with the newest datasets from the chain CMB+BAO+SNIa, to see whether they are able to alleviate the aforementioned tensions. We find that when the updated …

Stringent constraint on the CCC TL cosmology with $H(z)$ Measurements
Lei Lei (Purple Mountain Observatory, University of Science and Technology of China), Ze-Fan Wang (Purple Mountain Observatory, University of Science and Technology of China), Tong-Lin Wang (Purple Mountain Observatory, University of Science and Technology of China), Yi-Ying Wang (Purple Mountain Observatory), Guan-Wen Yuan (University of Trento, Trento Institute for Fundamental Physics and Applications), Wei-Long Li…

Stringent constraint on the CCC+TL cosmology with $H(z)$ Measurements
Recently, the Covarying Coupling Constants and Tired Light (CCC+TL) hybrid model was proposed to explain the unexpectedly small angular diameters of high-redshift galaxies observed by the James Webb Space Telescope (JWST) that are challenging to reconcile with the $Λ$CDM model. In this work, we test the CCC+TL model against model-independent Hubble parameter [$H(z)$] measurements obtained from cosmic chronometers. It turns out that the parameter set optimized for the type-Ia supernova (SN Ia) …

Preventing Singularity Problem in $f(R)$ Dark Energy Models
Romy Hanang Setya Budhi, Nehla Shobcha, Norma Sidik Risdianto
https://arxiv.org/abs/2508.20430 https://

Preventing Singularity Problem in $f(R)$ Dark Energy Models
The curvature singularity problem in $f(R)$ dark energy models poses a significant challenge to their viability as alternatives to the $Λ$CDM paradigm. In this work, we investigate the possibility of resolving this issue by incorporating higher-order corrections that are compatible with the inflationary phase. We analyze the effects of adding $R^2$, $R^{\frac{m+2}{m+1}}$ and $α$-attractor representation in $f(R)$ gravity terms to types of dark energy $f(R)$ models, focusing on their ability t…

Warm Dark Matter meets Cold Dark Matter Isocurvature
Sai Chaitanya Tadepalli, Tomo Takahashi
https://arxiv.org/abs/2508.03805 https://arxiv.org/pdf/2508.03…

Warm Dark Matter meets Cold Dark Matter Isocurvature
Isocurvature fluctuations can be generated in various scenarios in the early Universe. In particular, some specific models predict those with a blue-tilted spectrum, which is consistent with the constraints from cosmic microwave background such as Planck, although isocurvature fluctuations with an almost scale-invariant spectrum are severely constrained. We argue that cold dark matter (CDM) isocurvature fluctuations with blue-tilted spectrum are not only consistent with current cosmological dat…

Forecast constraints on null tests of the $\Lambda$CDM model with SPHEREx
Alejandro Mata Rom\'an, Indira Ocampo, Savvas Nesseris
https://arxiv.org/abs/2507.16604

Forecast constraints on null tests of the $Λ$CDM model with SPHEREx
In this work we quantify the ability of the upcoming SPHEREx survey to constrain cosmological observables and test the internal consistency of the cosmological constant and cold dark matter ($Λ$CDM) model. Using Fisher matrix forecasting, we assess the expected precision on Baryon Acoustic Oscillations (BAO) observables, such as the angular diameter distance $D_\mathrm{A}(z)$ and the Hubble parameter $H(z)$. We further explore SPHEREx's potential to probe some of the fundamental assumptions of…

Growth Index in the $\gamma\delta$CDM model
Cemsinan Deliduman, Furkan \c{S}akir Dilsiz, Selinay Sude Binici
https://arxiv.org/abs/2508.14749 https://arxiv…

Growth Index in the $γδ$CDM model
To better distinguish the nature of $H_0$ and $S_8$ tensions, it is necessary to separate the effects of expansion and the growth of structure. The growth index $γ$ was identified as the single parameter that characterizes the growth of density fluctuations independently of the effects of cosmic expansion. Analyses performed with various cosmological datasets indicate that the growth index has to be larger than its theoretically predicted value in the $Λ$CDM model. Cosmological models based o…

Position drift with Gaia
Andreas Tsigkas Kouvelis, Asta Heinesen, Shashank Shalgar, Miko{\l}aj Korzy\'nski
https://arxiv.org/abs/2508.02810 https://arx…

Position drift with Gaia
The proper motion (also known as position drift) field of extragalactic sources at cosmological distances across our sky can be used to measure the acceleration of the Solar System through the aberration effect. If measured very precisely, the signal would also hold cosmological information, for instance about bulk flows of distant sources or the presence of tensor modes. In the $Λ$ cold dark matter ($Λ$CDM) model, the acceleration of the Solar System is by far the dominant contributor to the…

Constraining deviations from $\Lambda$CDM in the Hubble expansion rate
Yupeng Yang
https://arxiv.org/abs/2508.17848 https://arxiv.org/pdf/2508.17848…

Constraining deviations from $Λ$CDM in the Hubble expansion rate
(abridged)We explore a phenomenological model that quantifies the deviation of the Hubble expansion rate from the standard scenario. The specific form of this model is expressed as $H^{2}(z) = H^{2}_{\rm ΛCDM}(Ω_m, z)[1+δ(z)]$. We consider three forms of $δ(z)$: model I, $δ(z)=δ_c$; model II, $δ(z)=δ_{c}z/(1+z)$, and model III, $δ(z)=δ_{c}{\rm ln}(1+z)$. Here, $δ_c$ represents a constant value. To constrain the models, we utilize a comprehensive set of observational data, including D…

Addressing Dipole Tension via Clustering in $\Lambda$CDM and beyond
Arefeh Daei Rasouli, Haniyeh S. Tadayyoni, Shant Baghram, Sohrab Rahvar
https://arxiv.org/abs/2508.18259 http…

Addressing Dipole Tension via Clustering in $Λ$CDM and beyond
The dipole in the angular distribution of the cosmic microwave background (CMB) is typically attributed to the Doppler effect and our motion relative to the CMB rest frame. It is expected that observations of large-scale structures would also exhibit a related kinematic dipole, helping to confirm the kinematic origin of the CMB dipole. However, numerous studies of the large-scale structure dipole have shown significant discrepancies with predictions based on the CMB. In this work, we investigat…

Observational Constraints on Scalar Field--Matter Interaction in Weyl Integrable Spacetime
Andronikos Paliathanasis
https://arxiv.org/abs/2506.16223 https:…

Observational Constraints on Scalar Field--Matter Interaction in Weyl Integrable Spacetime
We test an analytic cosmological solution within the framework of Weyl Integrable Spacetime using current observational data. In this model, dark energy is described by a pressureless fluid, while a scalar field arises naturally through the definition of the connection. This gravitational theory reveals a Chameleon Mechanism leading to a nonzero interaction between the scalar field and the matter sector. This model extends the standard $Λ$CDM cosmology by introducing one additional degree of f…

Lensing amplitude anomaly and varying electron mass alleviate the Hubble and $S_8$ tensions
Yi-Ying Wang, Lei Lei, Shao-Peng Tang, Yi-Zhong Fan
https://arxiv.org/abs/2508.19081 …

Lensing amplitude anomaly and varying electron mass alleviate the Hubble and $S_8$ tensions
Cosmological measurements have revealed tensions within the standard $Λ$CDM model, notably discrepancies in the Hubble constant and $S_8$ parameter. Additionally, recent observations suggested evidence of a possible non-flat spatial curvature and an anomalous CMB lensing amplitude that beyond the $Λ$CDM framework. In this study, we explore whether introducing a variation in the electron mass $m_e$, allowing non-zero spatial curvature $Ω_K$, and a free lensing amplitude $A_{\rm lens}$ can res…

Fractal Properties of the Cosmic Web
Jaan Einasto
https://arxiv.org/abs/2509.04252 https://arxiv.org/pdf/2509.04252…

Fractal Properties of the Cosmic Web
The cosmic web is one of the most complex systems in nature, consisting of galaxies and clusters of galaxies joined by filaments and walls, leaving large empty regions called cosmic voids. The most common method of describing the web is a correlation function and its derivative, the fractal function. In this paper, I provide a review of the fractal properties of the cosmic web from the observational point of view within the Newtonian concordance $Λ$CDM Universe framework. I give a brief histor…

Nearly Full-Sky Low-Multipole CMB Temperature Anisotropy: II. Angular Power Spectra and Likelihood
Hayley C. Nofi, Graeme E. Addison, Charles L. Bennett, Laura Herold, J. L. Weiland
https://arxiv.org/abs/2509.03719

Nearly Full-Sky Low-Multipole CMB Temperature Anisotropy: II. Angular Power Spectra and Likelihood
We present a CMB temperature power spectrum measurement at large angular scales from WMAP and Planck maps that were cleaned of foregrounds using a template-based approach described in a companion paper. We recover essentially the full-sky CMB information at multipoles $\ell<30$ with only 1% of pixels near the Galactic plane masked and no inpainting. Notable features continue to appear: (a) a low quadrupole power compared to the best-fit Planck 2018 $Λ$CDM spectrum at $2.2σ$, (b) a dip in the …

The Dark Energy Camera All Data Everywhere cosmic shear project V: Constraints on cosmology and astrophysics from 270 million galaxies across 13,000 deg$^2$ of the sky
D. Anbajagane, C. Chang, A. Drlica-Wagner, C. Y. Tan, M. Adamow, R. A. Gruendl, L. F. Secco, Z. Zhang, M. R. Becker, P. S. Ferguson, N. Chicoine, K. Herron, A. Alarcon, R. Teixeira, D. Suson, A. J. Shajib, J. A. Frieman, A. N. Alsina, A. Amon, F. Andrade-Oliveira, J. Blazek, C. R. Bom, H. Camacho, J. A. Carballo-Bello, A…

The Dark Energy Camera All Data Everywhere cosmic shear project V: Constraints on cosmology and astrophysics from 270 million galaxies across 13,000 deg$^2$ of the sky
We present constraints on models of cosmology and astrophysics using cosmic shear data vectors from three datasets: the northern and southern Galactic cap of the Dark Energy Camera All Data Everywhere (DECADE) project, and the Dark Energy Survey (DES) Year 3. These data vectors combined consist of 270 million galaxies spread across 13,000 ${\rm deg}^2$ of the sky. We first extract constraints for $Λ$CDM cosmology and find $S_8= 0.805^{+0.019}_{-0.019}$ and $Ω_{\rm m} = 0.262^{+0.023}_{-0.036}…

Dark energy era with a resolution of Hubble tension in generalized entropic cosmology
Priyanka Adhikary, Sudipta Das, Sergei D. Odintsov, Tanmoy Paul
https://arxiv.org/abs/2507.15273

Dark energy era with a resolution of Hubble tension in generalized entropic cosmology
We propose a new dark energy (DE) model from four parameter generalized entropy function of apparent horizon in a spatially flat universe. Such kind of generalized entropy is able to generalize all the known entropies proposed so far, for suitable representations of the entropic parameters. It turns out that the scenario can describe the correct thermal history of the universe, with the sequence of matter and dark energy epochs. Comparing with the $Λ$CDM model, the proposed generalized entropi…

Rapid cosmological inference with the two-loop matter power spectrum
Thomas Bakx, Henrique Rubira, Nora Elisa Chisari, Zvonimir Vlah
https://arxiv.org/abs/2508.00611 https://

Rapid cosmological inference with the two-loop matter power spectrum
We compute the two-loop effective field theory (EFT) power spectrum of dark matter density fluctuations in $Λ$CDM using the recently proposed COBRA method (Bakx. et al, 2025). With COBRA, we are able to evaluate the two-loop matter power spectrum in $\sim 1$ millisecond at $ \sim 0.1 \%$ precision on one CPU for arbitrary redshifts and on scales where perturbation theory applies. As an application, we use the nonlinear matter power spectrum from the Dark Sky simulation to assess the performanc…

Unveiling the Pitfalls of CPL Parametrization at High Redshifts: A Critical Assessment of the $\omega_{0}$$\omega_a$CDM Model with DESI DR2 BAO Data
Seokcheon Lee
https://arxiv.org/abs/2506.18230

Unveiling the Pitfalls of CPL Parametrization at High Redshifts: A Critical Assessment of the $ω_{0}$$ω_a$CDM Model with DESI DR2 BAO Data
We critically assess the w0waCDM model, employing the Chevallier-Polarski-Linder (CPL) parametrization, w(z) = w0 + wa * z / (1 + z), using Baryon Acoustic Oscillation (BAO) measurements from DESI Data Release 2 (DR2). While DESI BAO data broadly align with the standard LambdaCDM model, giving Omega_m = 0.3, our Markov Chain Monte Carlo fits show notable variation in best-fit values and degeneracy directions for w0waCDM across combinations of BAO observables (DV/rd, DM/rd, DH/rd, and DM/DH). …

Cosmographical analysis of sign-switching dark energy
Mariam Bouhmadi-L\'opez, Be\~nat Ibarra-Uriondo
https://arxiv.org/abs/2506.12139 https://

Cosmographical analysis of sign-switching dark energy
Inspired by the well-studied $Λ_{\rm s}$CDM model, we propose and investigate a class of dynamical dark energy models that evolve from a negative cosmological constant, transitioning to a positive value at low redshifts. Specifically, we introduce a dark energy framework based on a generalised ladder-step function for the cosmological constant. Furthermore, we present two additional models in which the cosmological constant undergoes a smooth sign change at a specified redshift. We provide a d…

Replaced article(s) found for astro-ph.CO. https://arxiv.org/list/astro-ph.CO/new
[1/1]:
- Is the $w_0w_a$CDM cosmological parameterization evidence for dark energy dynamics partially caus...
Chan-Gyung Park, Javier de Cruz Perez, Bharat Ratra

Neutrino mass tension or suppressed growth rate of matter perturbations?
William Giar\`e, Olga Mena, Enrico Specogna, Eleonora Di Valentino
https://arxiv.org/abs/2507.01848

Neutrino mass tension or suppressed growth rate of matter perturbations?
Assuming a minimal $Λ$CDM cosmology with three massive neutrinos, the joint analysis of Planck cosmic microwave background data, DESI baryon acoustic oscillations, and distance moduli measurements of Type Ia supernovae from the Pantheon+ sample sets an upper bound on the total neutrino mass, $\sum m_ν\lesssim 0.06$-$0.07$ eV, that lies barely above the lower limit from oscillation experiments. These constraints are mainly driven by mild differences in the inferred values of the matter density…

Modified cosmology through generalized mass-to-horizon entropy: observational constraints from DESI DR2 BAO data
Giuseppe Gaetano Luciano, Andronikos Paliathanasis
https://arxiv.org/abs/2508.13260

Modified cosmology through generalized mass-to-horizon entropy: observational constraints from DESI DR2 BAO data
A generalized mass-to-horizon entropy has recently been proposed as an extension of the Bekenstein-Hawking area law, derived from a modified mass-horizon relation constructed to ensure consistency with the Clausius equation. Within the gravity-thermodynamics conjecture, this entropy formulation yields modified Friedmann equations, which recover the standard $Λ$CDM cosmology in the appropriate limit of the model's two free parameters. In the present study, we constrain this framework using obse…

Can cosmic rotation resolve the Hubble tension? Constraints from CMB and large-scale structure
Micol Benetti, David A. Cook, Saulo Carneiro
https://arxiv.org/abs/2508.00759 http…

Can cosmic rotation resolve the Hubble tension? Constraints from CMB and large-scale structure
We investigate a relativistic cosmological model with background rotation, sourced by a non-perfect fluid with anisotropic stress. A modified version of the CLASS Boltzmann code is employed to perform MCMC analyses against Cosmic Microwave Background (CMB) and late-time datasets. The results show that current CMB data constrain the present-day rotation parameter to be negligible. As a consequence, the derived cosmological parameters remain consistent with the standard $Λ$CDM values. In contras…

Variational autoencoder for generating realistic $N$-body simulations for dark matter halos
Jazhiel Chac\'on-Lavanderos, Isidro G\'omez-Vargas, Ricardo Menchaca-Mendez, J. Alberto V\'azquez
https://arxiv.org/abs/2507.18054

Variational autoencoder for generating realistic $N$-body simulations for dark matter halos
In this paper, we explore the use of a variational autoencoder (VAE), a deep generative model, to compress and generate images of dark matter density fields from $Λ$CDM like cosmological simulations. The VAE learns a compact, low-dimensional representation of the large-scale structure, enabling both accurate reconstruction and generation of statistically realistic samples. We evaluated the generated images by comparing their power spectra to those of real simulations and the theoretical $Λ$CD…

Can an Anti-de Sitter Vacuum in the Dark Energy Sector Explain JWST High-Redshift Galaxy and Reionization Observations?
Anirban Chakraborty, Tirthankar Roy Choudhury, Anjan Ananda Sen, Purba Mukherjee
https://arxiv.org/abs/2509.02431

Can an Anti-de Sitter Vacuum in the Dark Energy Sector Explain JWST High-Redshift Galaxy and Reionization Observations?
The James Webb Space Telescope's (JWST) discovery of an unexpectedly high abundance of UV-bright galaxies at redshifts $z > 10$ poses a significant challenge to the standard $Λ$CDM cosmology. This work tests whether this tension can be resolved solely by modifying the cosmological background, without invoking significant evolution in the astrophysical properties of early galaxies. We investigate an alternative framework featuring the presence of an anti-de Sitter vacuum in the dark energy sect…

Reanalyzing DESI DR1: 1. $\Lambda$CDM Constraints from the Power Spectrum and Bispectrum
Anton Chudaykin, Mikhail M. Ivanov, Oliver H. E. Philcox
https://arxiv.org/abs/2507.13433 …

Reanalyzing DESI DR1: 1. $Λ$CDM Constraints from the Power Spectrum and Bispectrum
We present the first independent re-analysis of the galaxy clustering data from DESI Data Release 1, utilizing an effective field theory (EFT)-based full-shape model. We analyze the power spectra and bispectra of the public catalogs using a custom-built pipeline based on window-deconvolved quasi-optimal estimators, carefully accounting for all relevant systematic effects. Compared to the official collaboration analysis, we add the galaxy power spectrum hexadecapole and the bispectrum monopole, …

Probing Generalized Emergent Dark Energy with DESI DR2
Vipin kumar Sharma, Himanshu Chaudhary, Sanved Kolekar
https://arxiv.org/abs/2507.00835 https://

Probing Generalized Emergent Dark Energy with DESI DR2
As an update on the initial findings of DESI, the new results provide the first hint of potential deviations from a cosmological constant ($w=-1$), which, if confirmed with significance $>5σ$, will falsify the $Λ$CDM model. We consider a novel generalised form of an emergent dark energy model and confront this through various data sets (Baryon Acoustic Oscillation (BAO) data from Dark Energy Spectroscopic Instrument Data Release (DESI DR2), Type Ia Supernovae (SNe Ia) compilation, and Cosmic …

Dark Energy Survey Year 3 results: $w$CDM cosmology from simulation-based inference with persistent homology on the sphere
J. Prat (DES Collaboration), M. Gatti (DES Collaboration), C. Doux (DES Collaboration), P. Pranav (DES Collaboration), C. Chang (DES Collaboration), N. Jeffrey (DES Collaboration), L. Whiteway (DES Collaboration), D. Anbajagane (DES Collaboration), S. Sugiyama (DES Collaboration), A. Thomsen (DES Collaboration), A. Alarcon (DES Collaboration), A. Amon (DES Collabor…

Dark Energy Survey Year 3 results: $w$CDM cosmology from simulation-based inference with persistent homology on the sphere
We present cosmological constraints from Dark Energy Survey Year 3 (DES Y3) weak lensing data using persistent homology, a topological data analysis technique that tracks how features like clusters and voids evolve across density thresholds. For the first time, we apply spherical persistent homology to galaxy survey data through the algorithm TopoS2, which is optimized for curved-sky analyses and HEALPix compatibility. Employing a simulation-based inference framework with the Gower Street simul…

Mixed Dark Matter and Galaxy Clustering: The Importance of Relative Perturbations
\c{S}afak \c{C}elik, Fabian Schmidt
https://arxiv.org/abs/2508.21481 https://

Mixed Dark Matter and Galaxy Clustering: The Importance of Relative Perturbations
We develop a perturbative model to describe large-scale structure in cosmologies where dark matter consists of a mixture of cold (CDM) and warm (WDM) components. In such mixed dark matter (MDM) scenarios, even a subdominant warm component can introduce distinctive signatures via its free-streaming effects, altering the evolution of density and velocity perturbations. We present linear-order solutions for both total and relative perturbations in the two-fluid system, identifying novel contributi…

Revisiting cosmic acceleration with DESI BAO
Jincheng Wang, Hongwei Yu, Puxun Wu
https://arxiv.org/abs/2507.22575 https://arxiv.org/pdf/2507.22575

Revisiting cosmic acceleration with DESI BAO
We revisit the evolution of cosmic acceleration in a spatially flat $w_0w_a$CDM universe, in which the equation of state of dark energy takes the CPL parametrization, using the latest baryon acoustic oscillation (BAO) measurements from the Dark Energy Spectroscopic Instrument (DESI), in combination with Planck cosmic microwave background (CMB) data and several type Ia supernova datasets, including PantheonPlus, Union3, and DESY5. We analyze the deceleration parameter $q(z)$ and the jerk paramet…

Cosmography with DESI DR2 and SN data
Gabriel Rodrigues, Rayff de Souza, Jailson Alcaniz
https://arxiv.org/abs/2506.22373 https://arx…

Cosmography with DESI DR2 and SN data
In this paper, we present a kinematic analysis of the Universe's expansion history using cosmography, with a particular emphasis on the jerk parameter $j_0$, which is equal to one in the standard $Λ$CDM scenario. We use distance measurements from DESI DR2, both independently and in combination with current Type Ia supernova (SN) samples, to constrain the cosmographic parameters up to the fourth order without relying on a specific cosmological model. Our results show that for the DESI DR2 data …

The Concordance of Weak Lensing and Escape Velocity Mass Estimates for Galaxy Clusters
Alexander Rodriguez, Christopher J. Miller
https://arxiv.org/abs/2507.20938 https://

The Concordance of Weak Lensing and Escape Velocity Mass Estimates for Galaxy Clusters
In the $Λ$CDM paradigm, the masses of the galaxy clusters inferred using background galaxies via weak-lensing shear should agree with the masses measured using the galaxy projected radius-velocity phase-space data via the escape velocity profile. However, prior work indicates that the correlation between caustic-inferred escape masses and weak lensing masses is statistically consistent with zero. Based on recent advancements in the measurement of the escape edge and its physical interpretation…

Dark Forces Gathering
Peter W. Graham, Daniel Green, Joel Meyers
https://arxiv.org/abs/2508.20999 https://arxiv.org/pdf/2508.20999

Dark Forces Gathering
Recent observations of the cosmic microwave background (CMB) and baryon acoustic oscillations (BAO) show some tension with a $Λ$CDM cosmology. For one, the cosmological parameters determined by the CMB are at odds with the expansion history determined by latest BAO measurements. In addition, the combined data has placed uncomfortably strong constraints on neutrino mass. Both effects can be interpreted as negative neutrino mass, one describing the change to the expansion history and the other o…

Superhorizon fluctuations and the cosmic dipole problem
Ge Chen, Chengcheng Han, Linwei Qiu
https://arxiv.org/abs/2507.20462 https://arxiv.org/pdf/2507.204…

Superhorizon fluctuations and the cosmic dipole problem
Recent observations have identified a significant 4.9$σ$ tension between the cosmic dipole inferred from galaxy number counts and that derived from the Cosmic Microwave Background (CMB), suggesting a potential deviation from the cosmological principle. This work investigates whether superhorizon isocurvature perturbations in cold dark matter (CDM) can account for this discrepancy. We demonstrate that, unlike adiabatic modes which cancel at leading order, superhorizon isocurvature modes can gen…

Dark Degeneracy in DESI DR2: Interacting or Evolving Dark Energy?
Vitor Petri, Valerio Marra, Rodrigo von Marttens
https://arxiv.org/abs/2508.17955 https://

Dark Degeneracy in DESI DR2: Interacting or Evolving Dark Energy?
The standard $Λ$CDM model, despite its success, is challenged by persistent observational tensions in the Hubble constant ($H_0$) and the matter clustering amplitude ($S_8$), motivating the exploration of alternative cosmological scenarios. We investigate a dark energy model with a phenomenological interaction in the dark sector, constructed to be exactly degenerate at the background level with the Chevallier-Polarski-Linder (CPL) parameterization. This setup allows us to test whether models w…

The Magnetic Origin of Primordial Black Holes: A Viable Dark Matter Scenario
Subhasis Maiti
https://arxiv.org/abs/2508.19217 https://arxiv.org/pdf/2508.192…

The Magnetic Origin of Primordial Black Holes: A Viable Dark Matter Scenario
Primordial Black Holes (PBHs) are compelling candidates for explaining the present-day relic abundance of cold dark matter (CDM), yet their formation typically requires finely tuned early-universe dynamics. In this work, we propose a novel PBH formation mechanism within a well-established magnetogenesis framework. This scenario simultaneously accounts for the large-scale magnetic fields observed today and generates an enhanced curvature power spectrum at intermediate scales, leading to PBH form…

Quasar cosmology II: joint analyses with Cosmic Microwave Background
M. Benetti, G. Bargiacchi, G. Risaliti, S. Capozziello, E. Lusso, M. Signorini
https://arxiv.org/abs/2506.21477

Quasar cosmology II: joint analyses with Cosmic Microwave Background
Currently, the increasing availability of accurate cosmological probes leads to the emergence of tensions between data on the one hand and between theoretical predictions and direct observations on the other. Moreover, after 25 years since the discovery of the accelerated expansion of the Universe has elected the $Λ$CDM model as the reference model, resolving shortcomings of the standard cosmological model seems to be an unpostponed priority. Hence, it is key to test alternative models and inv…

Disformal interactions in the Dark Sector: From driving Early Dark Energy to confronting cosmological tensions
Pulkit Bansal (IIT Bombay), Joseph P. Johnson (IISER Mohali), S. Shankaranarayanan (IIT Bombay)
https://arxiv.org/abs/2508.17003

Disformal interactions in the Dark Sector: From driving Early Dark Energy to confronting cosmological tensions
The $Λ$CDM model faces significant challenges, including an incomplete understanding of the dark sector and persistent tensions in the Hubble constant and the clustering amplitude. To address these issues, we propose a general disformal coupling between dark energy (DE) and dark matter from a field-theoretic action which can generate a rich variety of interactions including conformal and pure-momentum coupling scenarios. Our analysis reveals that a pure disformal coupling naturally produces a …

Refined Constraints on the Hubble Constant from Localized FRBs with Assessment of Systematic Effects
Chenyuan Xu, Yi Feng, Jiaying Xu
https://arxiv.org/abs/2507.18946 https://…

Refined Constraints on the Hubble Constant from Localized FRBs with Assessment of Systematic Effects
The dispersion measure-redshift relation of fast radio bursts (FRBs) provides a valuable cosmological probe for constraining the Hubble constant, offering an independent measurement that could help resolve the ongoing Hubble tension. In this paper, we begin with a sample of 117 localized FRBs and use 95 of them to constrain $H_0$ to $71.28^{+1.90}_{-2.08}$ km s$^{-1}$ Mpc$^{-1}$ within the standard Lambda Cold Dark Matter ($Λ$CDM) model. The resulting statistical uncertainty is below 2.8\%, im…

Cosmological bounds on dark matter annihilation using dark ages 21-cm signal
Vivekanand Mohapatra
https://arxiv.org/abs/2506.20648 https://

Cosmological bounds on dark matter annihilation using dark ages 21-cm signal
We investigate the impact of dark matter (DM) annihilation on the global 21-cm signal during the dark ages and cosmic dawn eras. The 21-cm line provides a complementary probe for studying the nature of dark matter beyond standard cosmological observables. In the standard $Λ$CDM framework, the expected absorption amplitude of the dark ages global 21-cm signal is approximately $-42\, \rm mK$. However, energy injection from DM annihilation can significantly heat and ionize the intergalactic mediu…

DESIgning concordant distances in the age of precision cosmology: the impact of density fluctuations
David Camarena, Kylar Greene, John Houghteling, Francis-Yan Cyr-Racine
https://arxiv.org/abs/2507.17969

DESIgning concordant distances in the age of precision cosmology: the impact of density fluctuations
Discrepancies between distance measurements and $Λ$CDM predictions reveal notable features in the distance-redshift relation, possibly suggesting the presence of an evolving dark energy component. Given the central role of the Friedmann-Lemaître-Robertson-Walker (FLRW) metric in modeling cosmological distances, we investigate here whether these features instead point to a possible departure from the fundamental FLRW symmetries. Exploiting the transverse and line-of-sight distances provided by…

Cosmic Sign-Reversal: Non-Parametric Reconstruction of Interacting Dark Energy with DESI DR2
Yun-He Li, Xin Zhang
https://arxiv.org/abs/2506.18477 https://…

Cosmic Sign-Reversal: Non-Parametric Reconstruction of Interacting Dark Energy with DESI DR2
A direct interaction between dark energy and dark matter provides a natural and important extension to the standard $Λ$CDM cosmology. We perform a non-parametric reconstruction of the vacuum energy ($w=-1$) interacting with cold dark matter using the cosmological data from DESI DR2, Planck CMB, and three SNIa samples (PP, DESY5, and Union3). By discretizing the coupling function $β(z)$ into 20 redshift bins and assuming a Gaussian smoothness prior, we reconstruct $β(z)$ without assuming any …

A field-level reaction for screened modified gravity
Daniela Saadeh, Kazuya Koyama, Xan Morice-Atkinson
https://arxiv.org/abs/2506.18876 https://

A field-level reaction for screened modified gravity
We present a field-level reaction framework to emulate the nonlinear effects of screened modified gravity on the cosmic web. This approach is designed to enable field-level inference with data from Stage IV cosmological surveys. Building on the reaction method, which models the nonlinear matter power spectrum in modified gravity as corrections to a "pseudo" $Λ$CDM cosmology, we extend the method to full field-level predictions by applying it to the output of $N$-body simulations, including bot…

The Effects of Linear Matter Power Spectrum Enhancement on Dark Matter Substructure
Ethan O. Nadler, Vera Gluscevic, Andrew Benson
https://arxiv.org/abs/2507.16889 https://

The Effects of Linear Matter Power Spectrum Enhancement on Dark Matter Substructure
We present cosmological dark matter (DM)--only zoom-in simulations of a Milky Way (MW) analog originating from enhanced linear matter power spectra $P(k)$ relative to the standard cold, collisionless DM (CDM) cosmology. We consider a Gaussian power excess in $P(k)$ followed by a cutoff in select cases; this behavior could arise from early-universe physics that alters the primordial matter power spectrum or DM physics in the radiation-dominated epoch. We find that enhanced initial conditions (IC…

Cosmological Constraints on Neutrino Masses in a Second-Order CPL Dark Energy Model
Shubham Barua, Shantanu Desai
https://arxiv.org/abs/2508.16238 https://…

Cosmological Constraints on Neutrino Masses in a Second-Order CPL Dark Energy Model
Recent DESI results indicate a strong preference for dynamical dark energy (DE) when baryon acoustic oscillation (BAO) measurements are combined with supernovae (SNe) and cosmic microwave background (CMB) data using the Chevallier-Polarski-Linder (CPL) parameterization. We analyze the exponential (EXP) parameterization, which introduces a second-order correction to CPL. We determine and compare the 95% upper bounds on the sum of neutrino masses for three dark energy (DE) models -- $Λ$CDM, CPL,…

Estimating the baryon fraction in the IGM from well-localized FRBs and DESI data
Thais Lemos
https://arxiv.org/abs/2507.17693 https://arxiv.org/pdf/2507.17…

Estimating the baryon fraction in the IGM from well-localized FRBs and DESI data
Current measurements of Baryon Acoustic Oscillations (BAO) from the Dark Energy Spectroscopic Survey (DESI DR2), when combined with data from Type Ia supernovae (SNe), challenge the observational viability of the $Λ$-Cold Dark Matter ($Λ$CDM) model, motivating combinations of independent datasets to estimate cosmological quantities. In a previous communication, we presented a cosmological independent method to constrain the baryon fraction in the IGM ($f_{\mathrm{IGM}}$), where we derived rel…

A spherical hydrodynamical model of cosmic voids in {\Lambda}CDM and beyond
Tommaso Moretti, Giovanni Verza, Noemi Frusciante, Franceso Pace
https://arxiv.org/abs/2507.14120

A spherical hydrodynamical model of cosmic voids in ΛCDM and beyond
Cosmic voids have emerged as powerful probes for cosmology, providing complementary information on the large-scale structure of the universe. We present the first application of a hydrodynamical framework to model the evolution of cosmic voids. This approach offers a physically intuitive characterization of void dynamics and can naturally be applied to non-standard cosmologies. We derive the cosmology-dependent mapping that relates the linear (Lagrangian) and fully non-linear (Eulerian) evoluti…

Going beyond $S_8$: fast inference of the matter power spectrum from weak-lensing surveys
Cyrille Doux, Tanvi Karwal
https://arxiv.org/abs/2506.16434 https…

Going beyond $S_8$: fast inference of the matter power spectrum from weak-lensing surveys
Weak lensing surveys are often summarized by constraints on the derived parameter ${S_8\equivσ_8\sqrt{Ω_{\rm m}/0.3}}$, obscuring the rich scale and redshift information encoded in the data, and limiting our ability to identify the origin of any tensions with $Λ$CDM predictions from the cosmic microwave background. In this work, we introduce a fast and flexible framework to extract the scale-dependent matter power spectrum $P(k, z)$ from cosmic shear and CMB lensing measurements, parameteriz…

The Impact of $\Omega_{m0}$ Prior Bias on Cosmological Parameter Estimation: Reconciling DESI DR2 BAO and Pantheon SNe Data Combination Results
Seokcheon Lee
https://arxiv.org/abs/2506.16022

The Impact of $Ω_{m0}$ Prior Bias on Cosmological Parameter Estimation: Reconciling DESI DR2 BAO and Pantheon+ SNe Data Combination Results
Recent cosmological parameter analyses combining DESI DR2 Baryon Acoustic Oscillation (BAO) data with external probes, such as Pantheon+ Supernovae (SNe) observations, have reported deviations of the dark energy equation-of-state parameters ($\oo, \oa$) from the standard $Λ$CDM model predictions ($\oo=-1, \oa=0$). A notable aspect of these results is the role of $\Omo$ prior information from SNe, which is known to exhibit tension with BAO-only constraints. In this study, we rigorously investig…

Two dynamical scenarios for the binned Master sample interpretation
Giovanni Montani, Elisa Fazzari, Nakia Carlevaro, Maria Giovanna Dainotti
https://arxiv.org/abs/2507.14048

Two dynamical scenarios for the binned Master sample interpretation
We analyze two different scenarios for the late Universe dynamics, resulting into Hubble parameters deviating from the $Λ$CDM, mainly for the presence of an additional free parameter, which is the dark energy parameter. The first model consists of a pure evolutionary dark energy paradigm, as result of its creation by the gravitational field of the expanding Universe. The second model also considers an interaction of the evolutionary dark energy with the matter component, postulated via the con…

Inference of matter power spectrum at z=0 using DESI DR1 Full-Shape data
R. Cereskaite, E. Mueller, C. Howlett, Tamara M. Davis, J. Aguilar, S. Ahlen, D. Bianchi, D. Brooks, F. J. Castander, T. Claybaugh, A. Cuceu, A. de la Macorra, S. Ferraro, A. Font-Ribera, J. E. Forero-Romero, E. Gaztanaga, G. Gutierrez, C. Hahn, K. Honscheid, D. Huterer, M. Ishak, R. Joyce, S. Juneau, D. Kirkby, A. Kremin, O. Lahav, A. Lambert, M. Landriau, L. Le Guillou, M. Manera, A. Meisner, R. Miquel, J. Moust…

Inference of matter power spectrum at z=0 using DESI DR1 Full-Shape data
Measurements of galaxy distributions at large cosmic distances capture clustering from the past. In this study, we use a cosmological model to translate these observations into the present-day galaxy distribution. Specifically, we reconstruct the 3D matter power spectrum at redshift $ z = 0 $ using Dark Energy Spectroscopic Instrument (DESI) Year 1 (DR1) galaxy clustering data and Cosmic Microwave Background (CMB) observations, assuming the $ Λ\text{CDM} $ model, and compare it to the result a…