Simple-graduated dark energy and spatial curvature

  title={Simple-graduated dark energy and spatial curvature},
  author={Giovanni Acquaviva and {\"O}zg{\"u}r Akarsu and Nihan Katırcı and Jose Alberto V{\'a}zquez},
  journal={Physical Review D},
In this work, we first discuss the possibility that dark energy models with negative energy density values in the past can alleviate the H0 tension, as well as the discrepancy with the baryon acoustic oscillation (BAO) Lyman-α data, both which prevail within the ΛCDM model. We then investigate whether two minimal extensions of the ΛCDM model, together or separately, can successfully realize such a scenario: (i) the spatial curvature, which, in the case of spatially closed universe, mimics a… 

Figures and Tables from this paper

Is the dark energy equation of state parameter singular?

A dark energy with a negative energy density in the past can simultaneously address various cosmological tensions, and if it is to be positive today to drive the observed acceleration of the

Dynamical Analysis of Logarithmic Energy-Momentum Squared Gravity

We perform the dynamical system analysis of a cosmological model in the energy-momentum squared gravity (EMSG) of the form f ( T µν T µν ) = α ln( λT µν T µν ), which is known as energy-momentum log

Testing spatial curvature and anisotropic expansion on top of the $\Lambda$CDM model

We explore the possible advantages of extending the standard Λ CDM model by more realistic backgrounds compared to its spatially flat Robertson-Walker (RW) spacetime assumption, while preserving the

ΛsCDM model: ΛCDM model with a sign switching cosmological ‘constant’

Özgür Akarsu, ∗ Suresh Kumar, † Emre Özülker, 3, ‡ and J. Alberto Vazquez § Department of Physics, Istanbul Technical University, Maslak 34469 Istanbul, Turkey Department of Mathematics, Indira

Relaxing cosmological tensions with a sign switching cosmological constant

We present a further observational analysis of the Λ s CDM model proposed in Akarsu et al. [Phys. Rev. D 104, 123512 (2021)]. This model is based on the the recent conjecture suggesting the universe



A Simple Phenomenological Emergent Dark Energy Model can Resolve the Hubble Tension

Motivated by the current status of cosmological observations and significant tensions in the estimated values of some key parameters assuming the standard ΛCDM model, we propose a simple but radical

Cosmological implications of baryon acoustic oscillation measurements

We derive constraints on cosmological parameters and tests of dark energy models from the combination of baryon acoustic oscillation (BAO) measurements with cosmic microwave background (CMB) data and

Planck Collaboration], Planck 2015 results

  • XIII. Cosmological parameters, Astron. Astrophys. 594,
  • 2016


The combination of seven-year data from WMAP and improved astrophysical data rigorously tests the standard cosmological model and places new constraints on its basic parameters and extensions. By

To H 0 or not to H 0 ?

This paper investigates whether changes to late-time physics can resolve the ‘Hubble tension’. It is argued that many of the claims in the literature favouring such solutions are caused by a

Investigating Cosmic Discordance

We show that a combined analysis of cosmic microwave background anisotropy power spectra obtained by the Planck satellite and luminosity distance data simultaneously excludes a flat universe and a

To H0 or not to H0?

This paper investigates whether changes to late time physics can resolve the ‘Hubble tension’. It is argued that many of the claims in the literature favouring such solutions are caused by a

Generalized emergent dark energy model and the Hubble constant tension

Weiqiang Yang, ∗ Eleonora Di Valentino, † Supriya Pan, ‡ Arman Shafieloo, 5, § and Xiaolei Li ¶ Department of Physics, Liaoning Normal University, Dalian, 116029, P. R. China Institute for Particle

In the realm of the Hubble tension—a review of solutions * * In honor of the seminal work by E Hubble [1]

 The simplest ΛCDM model provides a good fit to a large span of cosmological data but harbors large areas of phenomenology and ignorance. With the improvement of the number and the accuracy of

Resolving the $$H_0$$ H 0 tension with diffusion

The tension between the value of the Hubble constant $$H_0$$ H 0 determined from local supernovae data and the one inferred from the cosmic microwave background based on the $$\Lambda $$ Λ CDM