Article
Astronomy & Astrophysics
Henrique Rubira, Rodrigo Voivodic
Summary: A logarithm transformation of the matter overdensity field allows information from higher-order functions to be transferred to the power spectrum, improving computational efficiency and accuracy. Studies show that the large-scale behavior of the log-transformed field can be represented by a small number of free parameters, and the non-linear transformation enables access to information on smaller scales.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Azadeh Moradinezhad Dizgah, Farnik Nikakhtar, Garrett K. Keating, Emanuele Castorina
Summary: Line intensity mapping is an emerging technique that has the potential to accurately probe signals at different scales and redshifts. By using simulations and modeling, researchers have been able to accurately predict clustering power and stochastic contributions of intensity fluctuations. Furthermore, this technique shows promise in measuring the baryon acoustic oscillations, which has important implications for cosmological studies in the future.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Luca Amendola, Massimo Pietroni, Miguel Quartin
Summary: We present a methodology to extend Fisher matrix forecasts to mildly non-linear scales without the need for selecting a cosmological model. By utilizing standard non-linear perturbation theory and assuming accurate measurements of cosmological distances, we parametrize the linear power spectrum and the growth rate in various k and z bins, obtaining model-independent constraints on the expansion rate and growth rate. Application of this technique to the Euclid and DESI specifications shows significant improvements in precision, especially when extending to higher k values. The absolute precision achieved for the expansion rate and growth rate at each redshift range is also discussed, highlighting the importance of considering non-linear corrections.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Elena Kozlikin, Robert Lilow, Felix Fabis, Matthias Bartelmann
Summary: By comparing the newly developed particle-based Kinetic Field Theory with the established Eulerian Standard Perturbation Theory, we find that in the non-interacting regime of free-streaming kinematics, Kinetic Field Theory contains a complete resummation of Standard Perturbation Theory, and the exact solution of Kinetic Field Theory cannot be recovered in any finite order of Standard Perturbation Theory. This suggests that Kinetic Field Theory may provide a better starting point for perturbative treatments of non-linear structure formation.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Weiqiang Yang, Supriya Pan, Eleonora Di Valentino, Olga Mena, Alessandro Melchiorri
Summary: Current cosmological data analyses show that a closed universe and interacting scenarios are attractive options for resolving the Hubble constant tension. However, the viability of these scenarios as global solutions to cosmological tensions may be compromised when considering other possible cosmological observations.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Francesco Sinigaglia, Francisco-Shu Kitaura, Andres Balaguera-Antolinez, Ikkoh Shimizu, Kentaro Nagamine, Manuel Sanchez-Benavente, Metin Ata
Summary: This work presents a new supervised machine-learning method, hydro-bam, which learns from a reference hydrodynamic simulation to reproduce the three-dimensional Ly alpha forest field in real and redshift space. The method achieves high accuracy in the statistics of the reconstructed fields and significantly reduces computing time.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Srijita Sinha, Narayan Banerjee
Summary: In this study, perturbations in a scalar field model driving recent acceleration were investigated, revealing distinctive qualitative features compared to the traditional ΛCDM model, particularly in reducing the amplitude of the matter power spectrum at an 8h(-1) Mpc scale.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Xin Wang
Summary: The paper studies the statistical evolution of the large-scale structure, with a focus on the joint probability distribution function. The evolution equation of this PDF describing probability conservation and the characteristic curves as effective dynamics are explored. This statistical approach provides valuable insights into scale interactions.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Roy Maartens, Sheean Jolicoeur, Obinna Umeh, Eline M. De Weerd, Chris Clarkson
Summary: Next-generation galaxy and 21cm intensity mapping surveys will rely on high-precision measurements of primordial non-Gaussianity using a combination of power spectrum and bispectrum. Theoretical precision at the same level is essential for these measurements. Incorporating a consistent general relativistic model of galaxy bias at second order extends the theoretical understanding of the galaxy bispectrum. The influence of primordial non-Gaussianity on the bispectrum goes beyond galaxy bias and dark matter density, and includes effects from redshift-space distortions.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Daniel Geiss, Ivan Kostyuk, Robert Lilow, Matthias Bartelmann
Summary: This paper presents a new analytical description of cosmic structure formation in a mixture of dark and baryonic matter using the framework of Kinetic Field Theory. The authors demonstrate how to extend the KFT formalism to describe mixtures of two particle species and show the validity of this approach by computing the linear evolution of matter power spectra. The results accurately reproduce expected behavior, showing suppression of structure growth on small scales in good agreement with numerical results.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Maria Archidiacono, Emanuele Castorina, Diego Redigolo, Ennio Salvioni
Summary: This study initiates the exploration of the cosmology of dark fifth forces, which are new forces acting solely on Dark Matter. It is found that the dark fifth force can be realized by a light scalar coupled to Dark Matter, and it has significant effects on the background cosmology and linear perturbations.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Samuel Brieden, Hector Gil-Marin, Licia Verde
Summary: This study presents a model-agnostic analysis of galaxy and quasar clustering data, providing precise constraints on cosmological parameters and offering important references for the choice of cosmological models.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Diogo P. L. Braganca, Matthew Lewandowski, David Sekera, Leonardo Senatore, Raphael Sgier
Summary: This paper extends the two-fluid system to two-loop order in perturbation theory, showing that a new linear counterterm proportional to the relative velocity of fluids may be present but its effects are expected to be small in the universe. The EFTofLSS at two-loop order accurately captures the baryonic processes on large scales and the differences in counterterms related to dark matter and baryons at different redshifts. The onset of star-formation physics is signaled around redshifts z ≈ 3 to z ≈ 2, which has implications for analyzing CMB-S4 data.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Samuel Brieden, Hector Gil-Marin, Licia Verde
Summary: This study measures two values of the Hubble expansion rate, H0, based on different physical processes using large-scale structure galaxy data and Big Bang Nucleosynthesis abundances information. The results show good consistency between the two H0 values obtained, which are the tightest sound-horizon free constraints from LSS data to date. Any proposed ACDM extension needs to modify consistently both the sound horizon scale physics and the matter-radiation equality scale to address the so-called Hubble tension.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Hector Gil-Marin
Summary: This study reviews different methods of combining cosmological information from the full shape of power spectra, finding that the standard approach of combining at the level of BAO variables is nearly optimal, resulting in improved constraints at a faster speed.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)