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Related papers: Testing the Swampland: $H_0$ tension

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Realising de Sitter vacua in string theory is challenging. For this reason it has been conjectured that de Sitter vacua inhabit the Swampland of inconsistent low-energy effective theories coupled to gravity. Since de Sitter is an attractor…

High Energy Physics - Theory · Physics 2019-04-24 Eoin Ó Colgáin , Maurice H. P. M. van Putten , Hossein Yavartanoo

We revisit the phenomenology of quintessence models in light of the recently refined version of the de Sitter Swampland conjecture, which includes the possibility of unstable de Sitter critical points. We show that models of quintessence…

High Energy Physics - Phenomenology · Physics 2018-11-19 Prateek Agrawal , Georges Obied

Motivated by the swampland dS conjecture, we consider a rolling scalar field as the source of dark energy. Furthermore, the swampland distance conjecture suggests that the rolling field will lead at late times to an exponentially light…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-24 Prateek Agrawal , Georges Obied , Cumrun Vafa

The string theory swampland proposes that there is no UV-completion for an effective field theory with an exact (metastable) de Sitter vacua, thereby ruling out standard $\Lambda$CDM cosmology if the conjecture is taken seriously. The…

High Energy Physics - Theory · Physics 2019-06-20 Suddhasattwa Brahma , Md. Wali Hossain

The $\Lambda$ Cold Dark Matter model ($\Lambda$CDM) represents the current standard model in cosmology. Within this, there is a tension between the value of the Hubble constant, $H_0$, inferred from local distance indicators and the angular…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 Edvard Mörtsell , Suhail Dhawan

We explore in this work whether Slotheon model of Dark Energy obeys the Swampland criteria of string theory. Since de Sitter vacuum is very difficult to construct in string theory the cosmological constant as an explanation of Dark Energy…

General Relativity and Quantum Cosmology · Physics 2019-08-05 Upala Mukhopadhyay , Debasish Majumdar

In this Letter, we study the implications of string Swampland criteria for dark energy in view of ongoing and future cosmological observations. If string theory should be the ultimate quantum gravity theory, there is evidence that exact de…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-12 Lavinia Heisenberg , Matthias Bartelmann , Robert Brandenberger , Alexandre Refregier

We study constraints imposed by two proposed string Swampland criteria on cosmology. These criteria involve an upper bound on the range traversed by scalar fields as well as a lower bound on $|\nabla_{\phi} V|/V$ when $V >0$. We find that…

High Energy Physics - Theory · Physics 2018-10-17 Prateek Agrawal , Georges Obied , Paul J. Steinhardt , Cumrun Vafa

We study a string-motivated theoretical prior on the quintessential dark energy model with exponential potential, \( V(\phi) = V_0 e^{-\lambda \phi} \), allowing for non-zero spatial curvature. First, we formulate the corresponding…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-22 Simran Arora , Hun Jang , Shinji Mukohyama

The recently proposed de Sitter swampland conjecture excludes local extrema of a scalar potential with a positive energy density in a low energy effective theory. Under the conjecture, the observed dark energy cannot be explained by the…

High Energy Physics - Theory · Physics 2018-12-26 Koichi Hamaguchi , Masahiro Ibe , Takeo Moroi

The Hubble tension refers to the discrepancy in the value of the Hubble constant $H_0$ inferred from the cosmic microwave background observations, assuming the concordance $\Lambda$CDM model of the Universe, and that from the distance…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-19 Yashi Tiwari , Basundhara Ghosh , Rajeev Kumar Jain

We discuss the cosmological implications of the string swampland conjectures for late-time cosmology, and test them against a wide range of state of the art cosmological observations. The refined de Sitter conjecture constrains either the…

High Energy Physics - Theory · Physics 2019-04-24 Marco Raveri , Wayne Hu , Savdeep Sethi

We propose a dark energy model in which a quintessence field $\phi$ rolls near the vicinity of a local maximum of its potential characterized by the simplest $S$ self-dual form $V(\phi) = \Lambda \ {\rm sech}(\sqrt{2} \, \phi/M_p)$, where…

High Energy Physics - Theory · Physics 2025-06-04 Luis A. Anchordoqui , Ignatios Antoniadis , Dieter Lust

The simplest cosmological model ($\Lambda$CDM) is well-known to suffer from the Hubble tension, namely an almost $5 \sigma$ discrepancy between the (model-based) early-time determination of the Hubble constant $H_0$ and its late-time (and…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-06 Darshan Kumar , Debajyoti Choudhury , Debottam Nandi

In this paper, the implications of string Swampland criteria for a dark energy-dominated universe, where we have a deviation from the cold dark matter model, will be discussed. In particular, we have considered two models. One of them is…

General Relativity and Quantum Cosmology · Physics 2023-08-03 Martiros Khurshudyan

The Hubble constant $H_0$ is one of the important cosmological parameters measuring the expansion rate of our universe at present moment. Over the last couple of years, $H_0$ has created an enormous amount of debates interests in the…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-29 Supriya Pan , Weiqiang Yang

We propose a dynamical dark energy model based on a canonical scalar field with a hybrid potential of the form $V(\phi) = V_{0}e^{-\lambda\phi} + V_{1}\phi^{n}$. We constrain the model's 11-dimensional parameter space using a comprehensive…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-30 Arpit Kottur , Jui Mahajan , Raka Dabhade

We interpret the de Sitter swampland conjecture in the thermodynamic point of view. When the number of degrees of freedom is enhanced as the modulus rolls down the potential, the bound on $m_{\rm Pl} \nabla V/V$ is equivalent to the…

High Energy Physics - Theory · Physics 2019-09-09 Min-Seok Seo

Local determinations of the Hubble constant $H_0$ favour a higher value than Planck based on CMB and $\Lambda$CDM. Through a model-independent expansion, we show that low redshift ($z \lesssim 0.7$) data comprising baryon acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-05 Aritra Banerjee , Haiying Cai , Lavinia Heisenberg , Eoin Ó Colgáin , M. M. Sheikh-Jabbari , Tao Yang

We examine the Swampland conjectures in the context of generic slow-roll thawing quintessence models. Defining $\lambda \equiv |V^{\prime}(\phi_i)/V(\phi_i)|$ and $K \equiv \sqrt{1 - 4V^{\prime \prime}(\phi_i)/3V(\phi_i)}$, where $\phi_i$…

High Energy Physics - Theory · Physics 2020-09-23 S. David Storm , Robert J. Scherrer
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