292 papers
This paper refutes claims that fourth-order scalar fields can solve the cosmological constant problem or generate primordial density perturbations without inflation, arguing instead that such theories inherently suffer from fatal pathologies including ghost-induced instabilities, unitarity violations, and the generation of a confining fifth force.
This paper investigates the unitarity violation scale of a non-minimally coupled scalar field with quartic self-coupling by calculating six-point scattering amplitudes in both Jordan and Einstein frames, explicitly demonstrating their frame-independence and showing that the dominant contribution arises from the scalar potential.
This paper proposes that quantum sensors can detect bursts of ultralight bosonic fields emitted during violent astrophysical events, thereby establishing a new multimessenger astronomy channel that remains viable even when accounting for matter screening effects.
This paper demonstrates that perturbative reheating following inflation systematically suppresses the gravitational wave signals from cosmological phase transitions compared to standard radiation-dominated scenarios, while introducing characteristic spectral features that could serve as distinctive signatures of the modified expansion history.
This paper proposes a unified framework where ultra-slow-roll inflation simultaneously generates primordial black hole dark matter, the baryon asymmetry via spontaneous baryogenesis, and a detectable stochastic gravitational wave background, establishing a predictive correlation between these phenomena that can be distinguished by future gravitational wave observatories like LISA, DECIGO, and the Einstein Telescope.
This paper proposes an amortized simulation-based inference method using neural posterior estimation for gravitational-wave ringdown analysis, demonstrating that it achieves statistically consistent parameter estimates orders of magnitude faster than traditional Markov-chain methods while revealing that transient noise contamination significantly biases mass and spin estimates, particularly when glitches occur during the signal's tail.
This paper utilizes a semi-analytical model of galaxy and supermassive black hole evolution within the CDM paradigm to demonstrate that the observed stellar mass–black hole mass relation at high redshifts disfavours fuzzy dark matter fields with masses below $2.0\times 10^{-20}$ eV and warm dark matter particles with masses below 7.2 keV at the 95% confidence level.
By analyzing X-ray selected AGN in the XXL and Stripe 82X surveys, this study finds that black hole mass, accretion rate, and luminosity show no significant correlation with large-scale dark matter halo environments, suggesting that AGN properties are primarily regulated by internal host-galaxy processes rather than external environmental factors.
This paper proposes an analytic, non-singular slow-roll inflation model where the conformal anomaly mechanism resolves the classical pressure singularity, generates extreme particle creation for reheating without inflaton oscillations, and enhances primordial black hole formation and secondary gravitational waves.
This paper proposes that an evolving intrinsic scatter and normalization in the supermassive black hole-bulge mass relation at high redshifts can reconcile the observed excess amplitude of the gravitational wave background with theoretical models while simultaneously explaining the existence of overmassive black holes in the early universe.
The paper introduces FlowSN, a novel simulation-based inference framework using normalizing flows to accurately model selection effects in Type Ia supernova cosmology, thereby significantly reducing biases in cosmological parameter estimation compared to conventional techniques.
This paper presents a color calibration for the Tip of the Red Giant Branch (TRGB) in JWST F090W and F150W filters, establishing an absolute magnitude of mag for low-metallicity populations and deriving revised, slightly closer distances for 16 galaxies relative to the NGC 4258 maser anchor.
This paper proposes using relativistic distortions in the Einstein radii of strong gravitational lenses, particularly when combined with spectroscopic velocity-dispersion measurements, to independently measure the kinematic cosmic dipole and potentially resolve the existing tension between CMB and source number count estimates of the observer's peculiar velocity at a significance level.
By deploying the new Arkenstone galactic wind model in cosmological simulations, this study demonstrates that high specific energy winds with energy loadings inversely scaling to halo mass effectively regulate star formation by heating the circumgalactic medium and suppressing gas accretion, achieving observational consistency with significantly lower mass loadings and supernova energy requirements than previous ejective feedback models.
This study forecasts that the Euclid mission will significantly constrain the Hu-Sawicki modified gravity parameter , achieving approximately 1% precision when combining spectroscopic and photometric probes and enabling the distinction of these models from the standard CDM cosmology at greater than 3 confidence.
Using FIRE-2 simulations of dwarf galaxies, this study demonstrates that the dark matter halo surface density remains nearly constant across both cold and self-interacting dark matter models (with and without baryons), yielding results consistent with observational data and established scaling relations.
This paper establishes that the Centaurus A and M83 galaxy pair is dynamically infalling toward each other with a total mass of approximately $6.36 \times 10^{12}\, M_\odot$, confirming their status as a compelling nearby analog to the Milky Way-Andromeda system in the Local Group.
This paper investigates the formation of primordial black holes in ultra-slow-roll inflation scenarios with a sharp transition, revealing through numerical simulations that while both vacuum bubble and adiabatic perturbation channels contribute, the latter dominates the mass function by a factor of $10100$ and is primarily driven by mean profiles.
Using CROCODILE hydrodynamic simulations with GADGET3/4-OSAKA, this study investigates the cosmic baryon distribution and the impact of AGN feedback by generating FRB light cones to constrain the diffuse baryon mass fraction up to z=1 and quantify how AGN-driven gas ejection reshapes the circumgalactic and intergalactic media.
This paper presents a fully Bayesian reanalysis of DESI DR2 data combined with CMB and supernovae, demonstrating that while frequentist methods suggest strong evidence for dynamical dark energy, Bayesian model selection largely favors the standard CDM model once calibration errors in the DES-SN5YR supernova data are corrected, revealing that the apparent tension was driven by systematic errors rather than new physics.