宇宙学与河外天体物理

In this work, we investigate a torsion-based cosmological model within the Einstei-Cartan framework, constrained by the latest combined datasets including DESI DR2 BAO, PantheonPlus and DESY5 supernovae, and the full Planck 2018 CMB…

We show that the gravothermal collapse of self-interacting dark matter (SIDM) halos can deviate from local thermodynamic equilibrium. As a consequence, the self-similar evolution predicted by the commonly adopted conducting fluid model can…

We investigate how statistical anisotropy (SA) in matter distributions affects the distributions of shapes and orientations of cluster-sized halos, using cosmological $N$-body simulations that incorporate SA. While the three-dimensional…

To assess the significance and scale dependence of anomalous large scale modes in the CatWISE quasar data, we generate smoothed number density fields on the sphere and study their extreme values -- maximum, minimum, maximum antipodal…

In this work, we perform a comprehensive joint analysis of three representative dark energy models - ${\rm{\Lambda}CDM}$, the Chevallier-Polarski-Linder (CPL) parametrization, and the Generalised Emergent Dark Energy (GEDE) model - using…

The baryonic features in the galaxy power spectrum offer tight, time-resolved constraints on the expansion history of the Universe but complicate the measurement of the broadband shape of the power spectrum, which also contains precious…

This paper has two aims: the first one is to build a large homogeneous spectrophotometric Type Ia supernova (SN Ia) sample, using 3069 spectra from the second Zwicky Transient Facility data release (ZTF DR2). Using this sample we reproduce,…

We investigate the prospects for observing a specific spectral distortion of the cosmic microwave background, which occurs due to the anisotropy of the radiation when it is scattered by hot plasma of galaxy clusters. Detection of this…

The inflationary $B$-mode signals encode invaluable information about the origin of our Universe and searching for potential signatures of primordial gravitational waves (PGWs) is one of the major science goals for future precision…

Weak gravitational lensing is a powerful probe of the universe's growth history. While traditional two-point statistics capture only the Gaussian features of the convergence field, deep learning methods such as convolutional neural networks…

We investigate the late-time imprints of three dark energy (DE) models, namely, the Chevallier-Polarski-Linder (CPL) parametrization, $\Lambda_{\rm s}$CDM, and an Omnipotent DE model, on cosmological observables sensitive to the time…

We investigate the imprints of memory-burdened primordial black holes (PBH) on the global 21 cm signal during the cosmic dawn. Recent studies reopened the possibility of a mass window of PBHs as a compelling candidate for dark matter,…

We present a new approach for extracting information about cosmic magnetic fields using cross-correlations between extragalactic Faraday rotation measure (RM) catalogs and galaxy surveys. Specifically, we propose measuring the two-point…

Ongoing and near-future spectroscopic surveys, such as DESI, DESI-II and Spec-S5, rely on imaging-based selections to construct uniform, three-dimensional tracers of large-scale structure. While spectroscopic data from these surveys…

The upcoming Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) is expected to discover nearly a million Type Ia supernovae (SNeIa), offering an unprecedented opportunity to constrain dark energy. The vast majority of these…

We introduce a novel estimator to quantify statistical tensions among multiple cosmological datasets simultaneously. This estimator generalizes the Difference-in-Means statistic, $Q_{\rm DM}$, to the multi-dataset regime. Our framework…

Line Intensity Mapping (LIM) has garnered attention as a powerful cosmological probe, with next-generation instruments such as SPHEREx preparing to map the evolution of large-scale structure during the Epoch of Reionization (EoR).…

The cosmic microwave background absorption intensity in the 21 cm line of neutral hydrogen in the presence of additional power in the form of a "bump" in the spectrum of cosmological density perturbations is calculated. The main…

One possible way to explain the observed effective dark energy equation of state crossing $w=-1$ (the phantom divide) is through modified gravity. A key point is to not view the expansion history in isolation but to take into account the…

We examine the use of a novel variant of Physics-Informed Neural Networks to predict cosmological parameters from recent supernovae and baryon acoustic oscillations (BAO) datasets. Our machine learning framework generates uncertainty…