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Related papers: Attractor behaviour in ELKO cosmology

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We solve a Boltzmann equation for massless quark and gluon fluids in a transversally homogeneous, longitudinally boost-invariant expansion. Quarks can be out of chemical equilibrium and the relaxation times of the two species are assumed to…

High Energy Physics - Phenomenology · Physics 2024-12-20 Ferdinando Frascà , Andrea Beraudo , Michael Strickland

In the paper, for the system which possesses both an attractor and a stable fixed point, we first formulate new stable control problems to find the asymptotically stable control function which realizes to transit a state moving around the…

Optimization and Control · Mathematics 2020-06-02 Fumihiko Nakamura

In this paper, we investigate the continuity of the attractors in time-dependent phase spaces. (i) We establish two abstract criteria on the upper semicontinuity and the residual continuity of the pullback $\mathscr D$-attractor with…

Analysis of PDEs · Mathematics 2022-01-11 Yanan Li , Zhijian Yang

There is increasing evidence from string theory that effective field theories are only reliable over approximately sub-Planckian field excursions. The two most promising effective models for early universe cosmology, inflation and…

High Energy Physics - Theory · Physics 2018-11-14 Jean-Luc Lehners

We study static neutron stars in the context of a class of non-minimally coupled inflationary potentials, the universal attractors. Universal attractors are known to generate a viable inflationary era, and they fall into the same category…

General Relativity and Quantum Cosmology · Physics 2021-09-01 V. K. Oikonomou

Recently, zero-point length cosmology has shown some positive insights into some non-singular aspects of the early Universe. In addition, topological defects are known to play a significant role by its presence as a part of the total energy…

General Relativity and Quantum Cosmology · Physics 2025-05-21 Kalyan Bhuyan , Mrinnoy M. Gohain

We present a phase-space analysis of cosmology containing multiple scalar fields with a positive or negative cross-coupling exponential potential. We show that there exist power-law kinetic-potential-scaling solutions for a sufficiently…

High Energy Physics - Theory · Physics 2007-05-23 Zong-Kuan Guo , Yun-Song Piao , Rong-Gen Cai , Yuan-Zhong Zhang

In this work the exact Friedmann-Robertson-Walker equations for an Elko spinor field coupled to gravity in an Einstein-Cartan framework are presented. The torsion functions coupling the Elko field spin-connection to gravity can be exactly…

General Relativity and Quantum Cosmology · Physics 2017-09-13 S. H. Pereira , S. S. A. Pinho , J. M. Hoff da Silva , J. F. Jesus

There has been considerable recent interest in a new class of non-slow roll inflationary solutions known as \textit{constant roll} inflation. Constant roll solutions are a generalization of the ultra-slow roll (USR) solution, where the…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-09 Wei-Chen Lin , Michael J. P. Morse , William H. Kinney

We study the non-equilibrium dynamics, thermalisation and attractor behaviour of charm quarks in a longitudinally expanding Quark-Gluon Plasma within the Relativistic Boltzmann Transport approach in 1+1D Bjorken expansion. Considering both…

High Energy Physics - Phenomenology · Physics 2026-04-06 Shile Chen , Vincenzo Nugara , Maria Lucia Sambataro , Salvatore Plumari , Vincenzo Greco

The quark-gluon plasma created in heavy-ion collisions is not in local thermal equilibrium at early times. Despite this, dissipative hydrodynamics describes the evolution of the energy-momentum tensor quite well after only roughly 0.5 - 1…

High Energy Physics - Phenomenology · Physics 2019-07-24 Michael Strickland

We obtain effective equations of inflationary dynamics for the mean inflaton and metric fields in the no-boundary and tunneling quantum states of the Universe. In the slow roll approximation (taking the form of the local Schwiger-DeWitt…

High Energy Physics - Theory · Physics 2011-07-19 A. O. Barvinsky , A. Yu. Kamenshchik

We present a general framework for analyzing spatially inhomogeneous cosmological dynamics. It employs Hubble-normalized scale-invariant variables which are defined within the orthonormal frame formalism, and leads to the formulation of…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Claes Uggla , Henk van Elst , John Wainwright , George F R Ellis

We study the cosmological consequences of the Extended Uncertainty Principle (EUP) by deriving modified Friedmann equations through thermodynamic arguments. The evolution of the effective equation of state induced by EUP corrections is…

General Relativity and Quantum Cosmology · Physics 2025-11-27 Maryam Roushan , Narges Rashidi

In this paper we investigate the induced inflation with two flat regions: one Starobinsky-like plateau in big field regime and one shorter plateau around the saddle point of the Einstein frame potential. This multi-phase inflationary…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-11 Michal Artymowski , Zygmunt Lalak , Marek Lewicki

Within the $\alpha$-attractors framework we investigate scalar potentials with the same pole as the one featured in the kinetic term. We show that, in field space, this leads to directions without a plateau. Using this, we present a…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-26 Konstantinos Dimopoulos , Michal Artymowski

The scenario of constant-roll inflation is studied where the inflaton is a scalar field with modified kinetic term, known as non-canonical scalar field. This modification leads to some changes in the slow-roll parameters, and also by taking…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-23 Abolhassan Mohammadi , Khaled Saaidi , Haidar Sheikhahmadi

We obtain cosmological constraints on models of inflation which exhibit rapid roll solutions. Rapid roll attractors exist for potentials with large mass terms and are thus of interest for inflationary model building within string theory. We…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-15 Takeshi Kobayashi , Shinji Mukohyama , Brian A. Powell

In this proceedings contribution, we summarize recent findings concerning the presence of early- and late-time attractors in non-conformal kinetic theory. We study the effects of varying both the initial momentum-space anisotropy and…

High Energy Physics - Phenomenology · Physics 2023-12-05 Huda Alalawi , Michael Strickland

One of the firm predictions of the single-scalar field inflationary cosmology is the consistency relation between the scalar and tensor perturbations. It has been argued that such a relation, if observationally verified, would offer strong…

Astrophysics · Physics 2010-02-09 Damien Gredat , S. Shankaranarayanan
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