宇宙学与河外天体物理
Context. The spatial distribution of haloes in the Cosmic Web encodes a wealth of information about the underlying cosmological model. These haloes can be represented as nodes of a graph, whose structural properties reflect cosmological…
An analysis is given of interacting dark energy and dark matter where the dark energy is assumed to be an ultralight axionic field with a pseudo-Nambu-Goldstone Boson potential which is in general a superposition of $N$ number of cosine…
High-precision measurements of the Cosmic Microwave Background (CMB) will soon allow for the unprecedented detection of small-scale secondary anisotropies, such as the kinetic Sunyaev-Zel'dovich (kSZ) effect. Linking the kSZ power spectrum…
We present a Gaussianity test of the cosmic microwave background (CMB) polarization by analyzing the statistics of unpolarized points in the sky, classified into three distinct types: saddles, comets, and beaks. This classification of…
Nonthermal emission observed in galaxy clusters provides a direct probe into the plasma physics of the intra-cluster medium (ICM) under extreme conditions. We report the first detailed analysis of the giant radio halo in the merging galaxy…
Large-scale $B$-mode polarization of the cosmic microwave background (CMB) is a prime target for current and future experiments in search of primordial gravitational waves (PGW). With increasingly sensitive instruments being deployed,…
Self-consistently modeling baryonic effects in survey-scale cosmological simulations has become increasingly important as the diversity, precision, and statistical reach of modern observations continue to improve. The advent of exascale…
We study a cosmological model featuring evolutionary dark energy, according to the idea that the creation of its constituents arises from the gravitational field of the expanding universe, whose non-equilibrium physics is described by a…
Gravitational waves induced by primordial density perturbations provide a powerful probe of the Universe's thermal history, which may include an early matter-dominated (eMD) era predicted by well-motivated particle-physics models. The…
The peak model of structure formation was built more than fifty years ago with the aim to address the origin of dark matter halo rotation in the tidal torque theory (TTT). Paradoxically, it has allowed one to explain and reproduce all halo…
Context. A comprehensive survey of Baryon Acoustic Oscillation (BAO) in the Large Scale Structure (LSS), in stratified data covering a finite redshift range is provided by the Dark Energy Spectroscopic Instrument (DESI). Extracting…
Time-delay cosmology offers an alternative approach to measuring the Hubble constant ($H_0$), which is distinct from the cosmic distance ladder and cosmic microwave background radiation methods. In this study, we present an improved strong…
The $\Lambda$CDM cosmolgical model has long been regarded as highly successful in accurately describing a wide range of astronomical observations. However, numerous observational findings have also provided hints of discrepancies from the…
Current and upcoming 21-cm experiments will soon be able to map 21-cm spatial fluctuations in three dimensions for a wide range of redshifts. However, bright foreground contamination and the nature of radio interferometry create significant…
This study presents the first extended comparison of cosmic filaments identified in SDSS DR10 observations ($z < 0.05$) and the IllustrisTNG300-1 $\Lambda$CDM simulation ($z = 0$), utilizing the novel GrAviPaSt filament-finder method. The…
The lightest Kaluza-Klein (KK) dark matter particles and primordial black holes (PBHs) emerge as plausible candidates for dark matter. In scenarios where dark matter is a mix of KK particles and PBHs, PBHs can attract surrounding KK dark…
One of the most crucial tests of the standard cosmological model consists on testing possible variations on fundamental physical constants. In frameworks such as the minimally extended varying speed of light model (meVSL), the relationship…
Large-scale structure (LSS) analysis in galaxy surveys is a powerful cosmological probe but is limited by tracer bias, which can obscure underlying information and weaken parameter constraints. Existing methods either model bias or restrict…
Primordial Black Holes (PBHs) may have formed in the early Universe due to the collapse of super-horizon curvature fluctuations. Simulations of PBH formation have been essential for inferring the initial conditions that lead to black hole…
It is known that stochastic gravitational wave backgrounds (SGWBs) have anisotropies generated by squeezed-type tensor non-Gaussianities originating from scalar-tensor-tensor (STT) and tensor-tensor-tensor cubic interactions. While the…