Article
Astronomy & Astrophysics
Miguel Aparicio Resco, Antonio L. Maroto
Summary: The study analyzes how to parametrize general modifications of the dark matter perturbations equations in a model-independent way, and shows that a general model with an imperfect and non-conserved dark matter fluid in a modified gravity scenario can be described with five general functions. It focuses on the sub-Hubble regime and finds that observable power spectra are sensitive to only three combinations of the initial five functions, which can help determine whether a modification of gravity or an imperfect/non-conserved dark matter is present. A Fisher forecast analysis for these three parameters is performed, with an example shown for a specific model with shear viscosity.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Wilmar Cardona, M. A. Sabogal
Summary: Interesting discrepancies in cosmological parameters challenge the success of the ACDM model. The Hubble constant and matter clustering strength derived from various measurements are higher/lower than those inferred from the Cosmic Microwave Background (CMB) in the context of ACDM. In this study, we propose a Dark Energy (DE) model with an evolving equation of state and constant sound speed squared to address these discrepancies. By considering the impact of DE sound speed on gravitational potential evolution, we find good agreement between our results and low redshift probes, but tension with BBN constraints in the case of baryon energy density.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Alvaro de la Cruz Dombriz, Francisco Jose Maldonado Torralba, David F. Mota
Summary: The stable pseudo-scalar degree of freedom in the quadratic Poincare Gauge theory of gravity is identified as a suitable candidate for dark matter. The study determines the parameter space in the theory that can explain all predicted cold dark matter phenomena and constrains these parameters with astrophysical observations.
Article
Astronomy & Astrophysics
Pedro Carrilho, Chiara Moretti, Benjamin Bose, Katarina Markovic, Alkistis Pourtsidou
Summary: Interacting dark energy models are proposed as alternatives to ACDM, and forthcoming galaxy clustering surveys will provide constraints on these models. This study compares three approaches of modeling non-linearities, considering a model with a simple 1-parameter extension to wCDM. Analysis using simulated data shows that the EFTofLSS-based model is better at describing data up to smaller scales and extracting more information, forecasting uncertainties on the dark energy equation of state and interaction parameter.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Z. Sakr
Summary: In this study, we performed a Bayesian analysis on three beyond CDM phenomenological triggering parameters using the latest cosmological probes. Our results show that the constraints on these parameters are compatible with general relativity and CDM.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Wilmar Cardona, David Figueruelo
Summary: We investigated a cosmological model that allows momentum transfer between dark matter and dark energy. The interaction in the dark sector mainly affects perturbations on small scales but does not resolve the H0 tension. Cosmological constraints confirm the contribution of momentum transfer to the a-8 discrepancy in the standard model. Future galaxy surveys will provide important information for testing models allowing momentum transfer in the dark sector.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Jackson Levi Said, Jurgen Mifsud, Joseph Sultana, Kristian Zarb Adami
Summary: This study utilizes a combined approach of Hubble parameter and redshift-space-distortion data to reconstruct the teleparallel gravity Lagrangian via Gaussian processes. Different combinations of datasets and kernels indicate that nontrivial cosmology beyond ΛCDM falls within the uncertainties of the reconstructions, suggesting no significant departure from the concordance cosmological model.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
M. Benetti, H. A. Borges, C. Pigozzo, S. Carneiro, J. S. Alcaniz
Summary: The observational viability of a class of interacting dark energy (iDE) models was investigated, with the best-fit favoring a positive interaction and ruling out the non-interacting case. A significant anti-correlation between the interaction parameter and the universe density curvature was found when considering a non-zero spatial curvature. The influence of the SHOES prior on the expansion rate had a significant impact on the results of the iDE model, but did not considerably change standard cosmology predictions.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Javier E. Gonzalez, Micol Benetti, Rodrigo von Marttens, Jailson Alcaniz
Summary: The paper discusses the implications of joint analyses using current data sets, focusing on non-flat universe and extensions of the standard cosmological model. Results suggest potential misleading conclusions in joint analysis, highlighting the dependence on spatial curvature and dark energy parameterizations.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Mohammad Ali Gorji, Hayato Motohashi, Shinji Mukohyama
Summary: In the context of scalar-tensor theories, stealth de Sitter solutions face issues of infinite strong coupling or gradient instability, which can be resolved by introducing a controlled detuning mechanism known as scordatura. This mechanism not only resolves the mentioned issues, but also ensures a well-defined quasi-static limit.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
F. B. M. dos Santos
Summary: We establish constraints on f (T) gravity by considering the possibility of a phantom crossing of the equation of state parameter coDE. Our analysis using combined data sets shows that a state where a phantom crossing of coDE happens is favored by data and the f (T) model is competitive with the ACDM model by statistical criteria. Additionally, we find evidence of the Hubble tension being alleviated within the f (T) model, indicating a possibility of addressing the current cosmic tensions.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2023)
Article
Astronomy & Astrophysics
Alexander Ganz
Summary: Minimally modified gravity models use auxiliary constraints to maintain a dynamic cosmological background, with results of linear perturbations being insensitive to constraint details, leading to a modified effective gravitational constant or a non-zero dust sound speed.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Bartolomeo Fiorini, Kazuya Koyama, Albert Izard
Summary: This study investigates the effects of two Modified Gravity (MG) theories on large-scale structure and validates the accuracy of fast approximate COLA simulations in predicting these effects. The results show that using the first three even multipoles of the redshift space power spectrum is sufficient to reproduce the influence of MG theories on the real space power spectrum. Additionally, the study highlights the importance of considering non-linear contributions and suggests that the effects of MG theories on the bispectrum and voids can be dominated by non-linear galaxy bias.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Peng-Ju Wu, Xin Zhang
Summary: The 21 cm intensity mapping technique is a powerful tool for measuring dark-energy parameters, with interferometers showing great potential for constraining cosmological parameters. The Tianlai cylinder array alone can achieve precision cosmology standards, while SKA1-MID performs well in constraining dynamical dark energy. Simulated 21 cm IM data can break parameter degeneracies and provide tighter constraints. Combining different observations offers promising survey strategies. The amplitude of residual foreground contamination significantly impacts constraint results.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2022)
Article
Astronomy & Astrophysics
Adria Gomez-Valent, Prajwal Hassan Puttasiddappa
Summary: Recent studies suggest that the Brans-Dicke cosmology with constant vacuum energy density might alleviate tensions found in the concordance cosmological model. Analyses in these studies indicate a preference for gravitational coupling values larger than Newton's constant, and improvements in cosmological datasets rely on mechanisms capable of screening modified gravity effects. Extensions of this cosmology show potential to maintain cosmological evolution while screening Brans-Dicke effects, but may struggle to explain significant departures from local measurements of gravitational coupling.
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2021)
Article
Astronomy & Astrophysics
Suhail Dhawan, Ariel Goobar, Edvard Mortsell
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2018)
Article
Astronomy & Astrophysics
Edvard Mortsell, Suhail Dhawan
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2018)
Article
Physics, Mathematical
Mikica Kocic, Marcus Hogas, Francesco Torsello, Edvard Mortsell
JOURNAL OF MATHEMATICAL PHYSICS
(2019)
Article
Astronomy & Astrophysics
Marvin Lueben, Edvard Mortsell, Angnis Schmidt-May
CLASSICAL AND QUANTUM GRAVITY
(2020)
Article
Astronomy & Astrophysics
S. Dhawan, J. Johansson, A. Goobar, R. Amanullah, E. Mortsell, S. B. Cenko, A. Cooray, O. Fox, D. Goldstein, R. Kalender, M. Kasliwal, S. R. Kulkarni, W. H. Lee, H. Nayyeri, P. Nugent, E. Ofek, R. Quimby
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)
Correction
Astronomy & Astrophysics
Francesco Torsello, Mikica Kocic, Marcus Hogas, Edvard Mortsell
CLASSICAL AND QUANTUM GRAVITY
(2020)
Article
Astronomy & Astrophysics
Mikica Kocic, Francesco Torsello, Marcus Hogas, Edvard Mortsell
CLASSICAL AND QUANTUM GRAVITY
(2020)
Article
Astronomy & Astrophysics
Marcus Hogas, Mikica Kocic, Francesco Torsello, Edvard Mortsell
CLASSICAL AND QUANTUM GRAVITY
(2020)
Article
Astronomy & Astrophysics
Marcus Hogas, Francesco Torsello, Edvard Mortsell
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
(2020)
Article
Astronomy & Astrophysics
E. Mortsell, J. Johansson, S. Dhawan, A. Goobar, R. Amanullah, D. A. Goldstein
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)
Article
Astronomy & Astrophysics
Edvard Mortsell, Ariel Goobar, Joel Johansson, Suhail Dhawan
Summary: This study investigates the impact of various sources of uncertainty in the supernova distance ladder and finds that the Cepheid color-luminosity calibration has a significant influence on the estimated Hubble constant. Excluding the effects of color excess, the inferred Hubble constant aligns with the Planck value.
ASTROPHYSICAL JOURNAL
(2022)
Article
Astronomy & Astrophysics
Edvard Mortsell, Ariel Goobar, Joel Johansson, Suhail Dhawan
Summary: Motivated by the diversity in extragalactic extinction properties, this study reanalyzes the Cepheid calibration used to infer the Hubble constant. Two different analyses are presented, showing similar results but tension with values inferred from the cosmic microwave background and Planck.
ASTROPHYSICAL JOURNAL
(2022)
Article
Mathematics, Applied
Marcus Berg, Kathrin Bringmann, Terry Gannon
Summary: This study focuses on defining one-parameter massive deformations of Maass forms and Jacobi forms, drawing inspiration from descriptions of plane gravitational waves in string theory. Examples of such deformations include massive Green's functions and massive modular graph functions.
COMMUNICATIONS IN NUMBER THEORY AND PHYSICS
(2021)
Article
Astronomy & Astrophysics
Francesco Torsello, Mikica Kocic, Marcus Hogas, Edvard Mortsell
Article
Astronomy & Astrophysics
Francesco Torsello, Mikica Kocic, Edvard Mortsell