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Related papers: Evidence for Emergent Dark Energy

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We present updated constraints on cosmological parameters in a 12-parameter model, extending the standard six-parameter $\Lambda$CDM by including dynamical dark energy (DE: $w_0$, $w_a$), the sum of neutrino masses ($\sum m_{\nu}$), the…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-19 Shouvik Roy Choudhury , Teppei Okumura

We present a Dark Energy (DE) model with a sound derivation as a natural extension of the Standard Model of particle physics with no free parameters and an excellent fit with current cosmological data improving by 21% the $\Lambda$CDM fit…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-24 A. de la Macorra , E. Almaraz

Dynamical dark energy has been recently suggested as a promising and physical way to solve the 3.4 sigma tension on the value of the Hubble constant $H_0$ between the direct measurement of Riess et al. (2016) (R16, hereafter) and the…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-24 Eleonora Di Valentino , Alessandro Melchiorri , Eric V. Linder , Joseph Silk

In this work, we study a class of early dark energy (EDE) models, in which, unlike in standard DE models, a substantial amount of DE exists in the matter-dominated era, self-consistently including DE perturbations. Our analysis shows that,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Ujjaini Alam

We present a complete analysis of the observational constraints and cosmological implications of our Bound Dark Energy (BDE) model aimed to explain the late-time cosmic acceleration of the universe. BDE is derived from particle physics and…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-15 Erick Almaraz , Axel de la Macorra

The recent findings from the Dark Energy Spectroscopic Instrument (DESI) indicate a preference for dynamical dark energy at a significance level above $2.5 \sigma$, with baryon acoustic oscillation (BAO) combined with cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-29 Jose Agustin Lozano Torres , Axel de la Macorra

The discrepancy between Planck data and direct measurements of the current expansion rate $H_0$ and the matter fluctuation amplitude $S_8$ has become one of the most intriguing puzzles in cosmology nowadays. The $H_0$ tension has reached…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-28 Safae Dahmani , Amine Bouali , Imad El Bojaddaini , Ahmed Errahmani , Taoufik Ouali

In this work, we first discuss the possibility that dark energy models with negative energy density values in the past can alleviate the $H_0$ tension, as well as the discrepancy with the baryon acoustic oscillation (BAO) Lyman-$\alpha$…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-09 Giovanni Acquaviva , Ozgur Akarsu , Nihan Katirci , J. Alberto Vazquez

Measurements of the current expansion rate of the Universe, $H_0$, using standard candles, disagree with those derived from observations of the Cosmic Microwave Background (CMB). This discrepancy, known as the Hubble tension, is substantial…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-05 Sergio Torres-Arzayus

This conference proceedings paper provides a short summary of the constraints presented by Menci et al. (2020) and Menci et al. (2022) to dynamical dark energy models. Dynamical dark energy (DDE) models have been proposed to address several…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-11 Paola Santini , Nicola Menci , Marco Castellano

Recent interest in New Early Dark Energy (NEDE), a cosmological model with a vacuum energy component decaying in a triggered phase transition around recombination, has been sparked by its impact on the Hubble tension. Previous constraints…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-02 Juan S. Cruz , Steen Hannestad , Emil Brinch Holm , Florian Niedermann , Martin S. Sloth , Thomas Tram

We present updated observational constraints on the spatially flat $\phi$CDM model, where dark energy is described by a minimally coupled scalar field $\phi$ with an inverse power-law potential $V=V_0 \phi^{-\alpha}$. Using Planck 2018 CMB…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-01 Chan-Gyung Park , Bharat Ratra

In this study, we explore the impact of various combinations of CMB-independent datasets, including the recent DESI BAO measurements, on the equation of state (EoS) of dark energy and other cosmological parameters within the framework of…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-13 Manisg Yadav , Archana Dixit , M. S. Barak , Anirudh Pradhan

Current cosmological data exhibit a tension between inferences of the Hubble constant, $H_0$, derived from early and late-universe measurements. One proposed solution is to introduce a new component in the early universe, which initially…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-12 J. Colin Hill , Evan McDonough , Michael W. Toomey , Stephon Alexander

Recent results from Type Ia supernovae (SNe Ia) and baryon acoustic oscillations (BAO), in combination with cosmic microwave background (CMB) measurements, have focused renewed attention on dark energy models with a time-varying…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-31 Anowar J. Shajib , Joshua A. Frieman

In this paper we fit two models of Early Dark Energy (EDE) (an increase in the expansion rate before recombination) to the combination of Atacama Cosmology Telescope (ACT) measurements of the Cosmic Microwave Background (CMB) with data from…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-05 Vivian Poulin , Tristan L. Smith , Alexa Bartlett

In this paper, we emphasise the recent observational findings from the Dark Energy Spectroscopic Instrument Data Release 2 (DESI DR2), which provide compelling evidence for a possible deviation from the standard $\Lambda$CDM (Cold Dark…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-04 Abhi Savaliya

We update the constraints on the cosmological parameters by adopting the Planck data released in 2015 and Baryon Acoustic Oscillation (BAO) measurements including the new DR14 quasar sample measurement at redshift $z=1.52$, and we conclude…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-06 Lu Chen , Qing-Guo Huang , Ke Wang

We investigate a phenomenological extension of the standard $\Lambda$CDM framework, the $\Omega_1\Omega_2$-$\Lambda$CDM model, in which the total energy density of the universe is expanded in powers of $1+z$. This parameterization recovers…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-20 Suresh Kumar

The Hubble tension persists as a challenge in cosmology. Even early dark energy (EDE) models, initially considered the most promising for alleviating the Hubble tension, fall short of addressing the issue without exacerbating other…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-12 Yan-Hong Yao , Xin-He Meng