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We provide a cosmological test of modified gravity with two tensorial degrees of freedom and no extra propagating scalar mode. The theory of gravity we consider admits a cosmological model that is indistinguishable from the $\Lambda$CDM…

宇宙学与河外天体物理 · 物理学 2022-09-01 Takashi Hiramatsu , Tsutomu Kobayashi

We re-analyze the nonlocal gravity model of Deser and Woodard which was proposed to account for the current phase of cosmic acceleration. We show that the growth of perturbations predicted by this nonlocal gravity model when its background…

宇宙学与河外天体物理 · 物理学 2017-04-05 Sohyun Park , Arman Shafieloo

We update the cosmological parameter estimation for three non-vanilla models by a joint analysis of \CCCP\ X-ray cluster, the newly released \Planck\ CMB data as well as some external data sets, such as baryon acoustic oscillation…

宇宙学与河外天体物理 · 物理学 2014-06-11 Jian-Wei Hu , Rong-Gen Cai , Zong-Kuan Guo , Bin Hu

The existence of 'peculiar' velocities due to the formation of cosmic structure marks a point of discord between the real Universe and the usually assumed Friedmann-Lema\'{i}tre-Robertson-Walker metric which accomodates only the smooth…

宇宙学与河外天体物理 · 物理学 2024-05-09 Roya Mohayaee , Mohamed Rameez , Subir Sarkar

We investigate the Hubble tension in the non-flat Super-$\Lambda {\rm CDM}$ model. The non-flat Super-$\Lambda {\rm CDM}$ model extends the Super-$\Lambda {\rm CDM}$ model by including the spatial curvature as a free parameter. The…

宇宙学与河外天体物理 · 物理学 2022-05-10 Saroj Adhikari

The current Hubble constant tension is usually presented by comparing constraints on $H_0$ only. However, the post-recombination background cosmic evolution is determined by two parameters in the standard $\Lambda$CDM model, the Hubble…

宇宙学与河外天体物理 · 物理学 2020-12-09 Weikang Lin , Katherine J. Mack , Liqiang Hou

We investigate two new observational perspectives in the context of torsional gravitational modification of general relativity, i.e., the $f(T)$ gravity: i) We use Pantheon data of type Ia supernovae motivated by a time variation of the…

宇宙学与河外天体物理 · 物理学 2023-03-21 Suresh Kumar , Rafael C. Nunes , Priya Yadav

Over the last decades, tests on the standard model of cosmology, the so-called $\Lambda$CDM model, have been widely analysed and compared with many different models for describing dark energy. Modified gravities have played an important…

广义相对论与量子宇宙学 · 物理学 2024-12-13 Sergei D. Odintsov , Diego Sáez-Chillón Gómez , German S. Sharov

We study quantum corrections to the $\Lambda$CDM model model arising from a minimum measurable length in Heisenberg's uncertainty principle. We focus on a higher-order Generalized Uncertainty Principle, beyond the quadratic form. This…

广义相对论与量子宇宙学 · 物理学 2025-12-25 Andronikos Paliathanasis , Genly Leon , Yoelsy Leyva , Giuseppe Gaetano Luciano , Amare Abebe

Cosmological constraints are usually derived under the assumption of a $6$ parameters $\Lambda$-CDM theoretical framework or simple one-parameter extensions. In this paper we present, for the first time, cosmological constraints in a…

宇宙学与河外天体物理 · 物理学 2015-12-30 Eleonora Di Valentino , Alessandro Melchiorri , Joseph Silk

We show that, in the presence of massive neutrinos, the Galileon gravity model provides a very good fit to the current CMB temperature, CMB lensing and BAO data. This model, which we dub ${\nu} \rm{Galileon}$, when assuming its stable…

宇宙学与河外天体物理 · 物理学 2015-06-11 Alexandre Barreira , Baojiu Li , Carlton Baugh , Silvia Pascoli

We analyze how predictions of cosmological models depend on a choice of described observational data, restrictions on flatness, and how this choice can alleviate the $H_0$ tension. These effects are demonstrated in the $w$CDM model in…

广义相对论与量子宇宙学 · 物理学 2020-02-11 G. S. Sharov , E. S. Sinyakov

The assumption of a flat Universe that follows the cosmological principle, i.e., that the universe is statistically homogeneous and isotropic at large scales, comprises one of the core foundations of the standard cosmological model --…

宇宙学与河外天体物理 · 物理学 2025-04-24 Mariana L. S. Dias , Antônio F. B. da Cunha , Carlos A. P. Bengaly , Rodrigo S. Gonçalves , Jonathan Morais

There has been recent interest in the cosmological consequences of energy-momentum-powered gravity models, in which the matter side of Einstein's equations is modified by the addition of a term proportional to some power, $n$, of the…

宇宙学与河外天体物理 · 物理学 2019-05-29 M. C. F. Faria , C. J. A. P. Martins , F. Chiti , B. S. A. Silva

We investigate the observational implications of a gravitational model wherein the gravitational constant $G$ and the cosmological constant $\Lambda$ exhibit scale-dependent behavior at the perturbative level, while preserving the General…

广义相对论与量子宇宙学 · 物理学 2025-05-06 Wiliam S. Hipólito-Ricaldi , Rodrigo von Marttens , Felipe de Melo-Santos , Davi C. Rodrigues

We obtain the reduced CMB data $\{l_A, R, z_*\}$ from WMAP9, WMAP9+BICEP2, Planck+WP and Planck+WP+BICEP2 for the $\Lambda$CDM and $w$CDM models with or without spatial curvature. We then use these reduced CMB data in combination with…

宇宙学与河外天体物理 · 物理学 2015-07-06 Rong-Gen Cai , Zong-Kuan Guo , Bo Tang

Accurate predictions for the non-linear matter power spectrum are needed to confront theory with observations in current and near future weak lensing and galaxy clustering surveys. We propose a computationally cheap method to create an…

宇宙学与河外天体物理 · 物理学 2020-01-01 Hans Winther , Santiago Casas , Marco Baldi , Kazuya Koyama , Baojiu Li , Lucas Lombriser , Gong-Bo Zhao

In this paper we place observational constraints on the well-known $\gamma$-gravity $f(R)$ model using the latest cosmological data, namely we use the latest growth rate, Cosmic Microwave Background, Baryon Acoustic Oscillations, Supernovae…

宇宙学与河外天体物理 · 物理学 2018-07-17 Clara Álvarez Luna , Spyros Basilakos , Savvas Nesseris

We explore nonlocally modified models of gravity, inspired by quantum loop corrections, as a mechanism for explaining current cosmic acceleration. These theories enjoy two major advantages: they allow a delayed response to cosmic events,…

天体物理学 · 物理学 2011-05-31 S. Deser , R. P. Woodard

In the context of the Relativistic Quantum Geometry formalism, where the cosmological constant is promoted to a dynamical variable by attributing it a geometric interpretation as a result of a flux on the boundary of a manifold and…

广义相对论与量子宇宙学 · 物理学 2025-04-15 Juan Ignacio Musmarra , Claudia Moreno , Rafael Hernández-Jiménez