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We propose a dynamical (quintessence) model of dark energy in the current universe with a renormalizable (Higgs-like) scalar potential. We prove the viability of our model (after fine tuning) for the certain range of the average scalar…

High Energy Physics - Theory · Physics 2015-03-17 Sergei V. Ketov , N. Watanabe

Recently implemented quantum devices such as quantum processors and quantum simulators combine highly complicated quantum dynamics with high-resolution measurements. We present a passivity deformation methodology that sets thermodynamic…

Quantum Physics · Physics 2021-03-10 Raam Uzdin , Saar Rahav

A particular class of flat Emergent Universe scenario is studied in light of recent observational data. Observationally permissible ranges of values are obtained for the model parameters. The class of model studied here can accommodate…

General Relativity and Quantum Cosmology · Physics 2011-09-16 S. Ghose , B. C. Paul

In this work we have performed the dynamical system analysis for steep(er) exponential potentials considering different values of the steepness index $n$. We have performed the analysis using centre manifold theory as well as by employing…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Sudipta Das , Manisha Banerjee , Nandan Roy

Irreversible thermodynamics of simple fluids have been connected recently to the theory of dynamical systems and some interesting assumptions have been made about the nature of the associated invariant measures. We show that the tests of…

chao-dyn · Physics 2008-02-03 Jean-Pierre Eckmann , Itamar Procaccia

We study the inverse problem of deducing the dynamical characteristics (such as the potential field) of large systems from kinematic observations. We show that, for a class of steady-state systems, the solution is unique even with…

Astrophysics · Physics 2008-11-14 Mikko Kaasalainen

We present a new approach to build models of quintessence interacting with dark or baryonic matter. We use a variational approach for relativistic fluids to realize an effective description of matter fields at the Lagrangian level. The…

General Relativity and Quantum Cosmology · Physics 2015-06-10 Christian G. Boehmer , Nicola Tamanini , Matthew Wright

Recent cosmological observations suggest that the dark energy equation of state may have changed in the latter stages of cosmic history. We introduce a quintessence scenario, termed bounded dark energy, capable of explaining this feature in…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-18 Giulia Borghetto , Ameek Malhotra , Gianmassimo Tasinato , Ivonne Zavala

Observational constraints on time-varying dark energy ({\it e.g.}, quintessence) are commonly presented on a $w_0$-$w_a$ plot that assumes the equation of state of dark energy strictly satisfies $w(z)= w_0+ w_a z/(1+z)$ as a function of the…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-21 David Shlivko , Paul Steinhardt

We study the thermodynamic history of composite Dark Matter models. We start with classifying the models by means of the symmetries partially protecting the composite Dark Matter decays and constrain their lifetimes. For each model, we…

High Energy Physics - Phenomenology · Physics 2020-05-21 Nicola Andrea Dondi , Francesco Sannino , Juri Smirnov

We use dynamical systems methods to study quintessence models in a spatially flat and isotropic spacetime with matter and a scalar field with potentials for which $\lambda(\varphi)=-V_{,\varphi}/V$ is bounded, thereby going beyond the…

General Relativity and Quantum Cosmology · Physics 2022-12-08 Artur Alho , Claes Uggla , John Wainwright

We study dark energy through the viewpoints of parametric and nonparametric analyses of late-time cosmological data. We consider four Hubble parameter priors reflecting the Hubble tension and make use of two phenomenological functions,…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-27 Reginald Christian Bernardo , Daniela Grandón , Jackson Levi Said , Víctor H. Cárdenas

A novel paradigm for thermal dark matter (DM), termed "bouncing dark matter", is presented. In canonical thermal DM scenarios, the DM abundance falls exponentially as the temperature drops below the mass of DM, until thermal freezeout…

High Energy Physics - Phenomenology · Physics 2022-10-05 Bibhushan Shakya

This paper uses the beta function formalism to extend the analysis of quintessence cosmological parameters to the logarithmic and exponential dark energy potentials. The previous paper (Thompson 2018) demonstrated the formalism using power…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-14 Rodger I. Thompson

Dark energy and dark matter are the dominant sources in the evolution of the late universe. They are currently only indirectly detected via their gravitational effects, and there could be a coupling between them without violating…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Christian G. Boehmer , Gabriela Caldera-Cabral , Ruth Lazkoz , Roy Maartens

$\phi$CDM models provide an alternative to the standard $\Lambda$CDM paradigm, while being physically better motivated. These models lead to a time-dependent speed of sound for dark energy that is difficult to replicate by $w$CDM…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-29 Olga Avsajanishvili , Gennady Y. Chitov , Tina Kahniashvili , Sayan Mandal , Lado Samushia

Some existing approaches to modeling the thermodynamics of moist air make approximations that break $\textit{thermodynamic consistency}$, such that the resulting thermodynamics do not obey the 1st and 2nd laws or have other inconsistencies.…

Atmospheric and Oceanic Physics · Physics 2022-09-05 Christopher Eldred , Mark Taylor , Oksana Guba

Tsallis entropy is a generalization of the Boltzmann-Gibbs entropy in statistical theory which uses a parameter $\delta$ to measure the deviation from the standard scenario quantitatively. Using concepts of Tsallis entropy and future event…

General Physics · Physics 2022-04-19 Bramha Dutta Pandey , Suresh Kumar P , Pankaj , Umesh Kumar Sharma

We baseline with current cosmological observations to forecast the power of the Dark Energy Spectroscopic Instrument (DESI) in two ways: 1. the gain in constraining power of parameter combinations in the standard $\Lambda$CDM model, and 2.…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-29 Samuel Goldstein , Minsu Park , Marco Raveri , Bhuvnesh Jain , Lado Samushia

In this paper, we use quadratic forms diagonalization methods applied to the function thermodynamic energy to analyze the stability of physical systems. Taylor's expansion was useful to write a quadratic expression for the energy function.…

Statistical Mechanics · Physics 2020-04-14 F. N. Lima , J. M. De Sousa