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Related papers: Towards Early Dark Energy in String Theory

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In this paper, we investigate the interaction between early dark energy (EDE) and scalar field dark matter, proposing a coupled scalar fields model to address the Hubble tension and $S_8$ tension. While the EDE model successfully alleviates…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-31 Gang Liu , Zhihuan Zhou , Yuhao Mu , Lixin Xu

Early dark energy (EDE) is a proposed solution to the Hubble tension in which a new cosmological field accelerates cosmic expansion prior to recombination and reduces the physical size of the sound horizon. In previous work, a slight…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-04 Adrien La Posta , Thibaut Louis , Xavier Garrido , J. Colin Hill

Cosmological models are often motivated and formulated in the language of particle physics, using quantities such as the axion decay constant, but tested against data using ostensibly physical quantities, such as energy density ratios,…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-16 Michael W. Toomey , Mikhail M. Ivanov , Evan McDonough

We consider an Early Dark Energy (EDE) cosmological model, and perform an analysis which takes into account both background and perturbation effects via the parameters $c^{2}_{\rm eff}$ and $c^{2}_{\rm vis}$, representing effective sound…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-17 Hasti Khoraminezhad , Matteo Viel , Carlo Baccigalupi , Maria Archidiacono

Early dark energy is a promising potential resolution of the Hubble tension. Unfortunately, many models suffer from the need to fine-tune their initial conditions to ensure that the epoch of early dark energy coincides with matter-radiation…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-06 Omar F. Ramadan , Tanvi Karwal , Jeremy Sakstein

A dark energy-like component in the early universe, known as early dark energy (EDE), is a proposed solution to the Hubble tension. Currently, there is no consensus in the literature as to whether EDE can simultaneously solve the Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-03 Laura Herold , Elisa G. M. Ferreira , Eiichiro Komatsu

The early dark energy (EDE) extension to $\Lambda$CDM has been proposed as a candidate scenario to resolve the "Hubble tension". We present new constraints on the EDE model by incorporating new data from the Dark Energy Spectroscopic…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-26 Frank J. Qu , Kristen M. Surrao , Boris Bolliet , J. Colin Hill , Blake D. Sherwin , Hidde T. Jense

Polarization of the cosmic microwave background (CMB) is sensitive to new physics violating parity symmetry, such as the presence of a pseudoscalar "axionlike" field. Such a field may be responsible for early dark energy (EDE), which is…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-31 Johannes R. Eskilt , Laura Herold , Eiichiro Komatsu , Kai Murai , Toshiya Namikawa , Fumihiro Naokawa

Recently the Dark Energy Spectroscopic Instrument (DESI) provided constraints on the expansion history from their Data Release 2 (DR2). The DESI baryon acoustic oscillation (BAO) measurements are well described by a flat $\Lambda$CDM model,…

A promising idea to resolve the long standing Hubble tension is to postulate a new subdominant dark-energy-like component in the pre-recombination Universe which is traditionally termed as the Early Dark Energy (EDE). However, as shown in…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-03 Anton Chudaykin , Dmitry Gorbunov , Nikita Nedelko

The Hubble tension arises from different observations between the late-time and early Universe. We explore a new model with dark fluid, called the exponential Acoustic Dark Energy (eADE) model, to relieve the Hubble tension. The eADE model…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-12 Lu Yin

Many quintessence models possess scaling or attractor solutions where the fraction of dark energy follows the dominant component in previous epochs of the expansion, or phase transitions may happen close to matter-radiation equality time. A…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-03 Adrià Gómez-Valent , Ziyang Zheng , Luca Amendola , Valeria Pettorino , Christof Wetterich

In this work, we explore the possibility that Early Dark Energy (EDE) is dynamical in nature and study its effect on cosmological observables. We introduce a parameterization of the equation of state allowing for an equation of state $w$…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-04 Ravi Kumar Sharma , Subinoy Das , Vivian Poulin

The analysis of the Cosmic Microwave Background (CMB) data acquired by the Atacama Cosmology Telescope (ACT) and the large-scale ($\ell\lesssim1300$) Planck Telescope show a preference for the Early Dark Energy (EDE) theory, which was set…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-30 Weiyang Liu , Hu Zhan , Yan Gong , Xin Wang

We investigate the constraints on early dark energy (EDE) by combining the most recent CMB observations available, ACT DR4, SPT-3G, and Planck2018 ($\ell_\text{TT,max}=1000$) data. This combined CMB dataset favors non-zero EDE fractions and…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-25 Jun-Qian Jiang , Yun-Song Piao

Early dark energy (EDE) models are a class of quintessence dark energy with a dynamically evolving scalar field which display a small but non-negligible amount of dark energy at the epoch of matter-radiation equality. Compared with a…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-02 Difu Shi , Carlton M. Baugh

New early dark energy (NEDE) makes the cosmic microwave background consistent with a higher value of the Hubble constant inferred from supernovae observations. It is an improvement over the old early dark energy model (EDE) because it…

High Energy Physics - Phenomenology · Physics 2022-03-23 Florian Niedermann , Martin S. Sloth

Current cosmological data exhibit discordance between indirect and some direct inferences of the present-day expansion rate, $H_0$. Early dark energy (EDE), which briefly increases the cosmic expansion rate prior to recombination, is a…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-19 Samuel Goldstein , J. Colin Hill , Vid Iršič , Blake D. Sherwin

We evaluate the effectiveness of Early Dark Energy (EDE) in addressing the Hubble tension using data from the completed eBOSS survey, focusing on luminous red galaxies (LRGs), quasars (QSOs), and emission line galaxies (ELGs). We perform…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-22 Rafaela Gsponer , Ruiyang Zhao , Jamie Donald-McCann , David Bacon , Kazuya Koyama , Robert Crittenden , Theo Simon , Eva-Maria Mueller

The standard cosmological model is in the midst of a stress test, thanks to the tension between supernovae-based measurements of the Hubble constant $H_{0}$ and inferences of its values from Cosmic Microwave Background (CMB) anisotropies.…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-05 K. Rezazadeh , A. Ashoorioon , D. Grin