English
Related papers

Related papers: Spinor quintom cosmology with intrinsic spin

200 papers

We perform a dynamical system analysis of Myrzakulov or F(R, T) gravity, which is a subclass of affinely connected metric theories, where ones uses a specific but non-special connection, which allows for non-zero curvature and torsion…

General Relativity and Quantum Cosmology · Physics 2022-11-30 G. Papagiannopoulos , Spyros Basilakos , Emmanuel N. Saridakis

Several kinds of astronomical observations, interpreted in the framework of the standard Friedmann-Robertson-Walker cosmology, have indicated that our universe is dominated by a Cosmological Constant. The dimming of distant Type Ia…

Astrophysics · Physics 2014-11-18 Subir Sarkar

We numerically and analytically explore the background cosmological dynamics of multifield dark energy with highly nongeodesic or "spinning" field-space trajectories. These extensions of standard single-field quintessence possess appealing…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-25 Johannes R. Eskilt , Yashar Akrami , Adam R. Solomon , Valeri Vardanyan

Motivated by results implying that the constituents of dark matter (DM) might be collisional, we consider a cosmological (toy-) model, in which the DM itself possesses some sort of thermodynamic properties. In this case, not only can the…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Kostas Kleidis , Nicholas K. Spyrou

We introduce a natural model of quintessence in string theory where the light rolling scalar is radiatively stable and couples to Standard Model matter with weaker-than- Planckian strength. The model is embedded in an anisotropic type IIB…

High Energy Physics - Theory · Physics 2015-06-04 Michele Cicoli , Francisco G. Pedro , Gianmassimo Tasinato

A two-component fluid representing dark energy is studied. One of the components has a polytropic form, while the other has a barotropic form. Exact solutions are obtained and the cosmological parameters are constrained using supernova type…

In this paper, we consider a normal branch of the DGP cosmological model with a quintessence scalar field on the brane as the dark energy component. Using the dynamical system approach, we study the stability properties of the model. We…

General Relativity and Quantum Cosmology · Physics 2021-02-24 Arvin Ravanpak , Golnaz Farpour Fadakar

This paper deals with dark and phantom energy in the tachyon and sub-quantum models for dark energy. We obtain that the simplest condition for such a regime to occur in these scenarios is that the scalar field be Wick rotated to imaginary…

High Energy Physics - Theory · Physics 2007-05-23 Pedro F. Gonzalez-Diaz

Spinor structure and internal symmetries are considered within one theoretical framework based on the generalized spin and abstract Hilbert space. Complex momentum is understood as a generating kernel of the underlying spinor structure. It…

Mathematical Physics · Physics 2015-12-07 V. V. Varlamov

We study cosmological perturbations arising from thermal fluctuations in the big-bounce cosmology in the Einstein-Cartan-Sciama-Kibble theory of gravity. We show that such perturbations cannot have a scale-invariant spectrum if fermionic…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-05 Nikodem J. Poplawski

In this letter, we study the condition for a generalized DBI action providing a quintom scenario of dark energy. We consider a development of string-inspired quintom by introducing non-minimal coupling. Then we show that the bouncing…

High Energy Physics - Theory · Physics 2008-11-26 M. R. Setare , J. Sadeghi , A. Banijamali

We propose a dark energy density based on the Gauss-Bonnet 4-dimensional invariant and its modification. This model avoids the necessity of introducing the black hole limit to define the holographic density, since it can be considered as a…

General Relativity and Quantum Cosmology · Physics 2013-08-30 L. N. Granda

Dark energy cosmologies with an equation of state parameter $w$ less than -1 are often found to violate the null energy condition and show unstable behaviour. A solution to this problem may require the existence of a consistent effective…

High Energy Physics - Theory · Physics 2009-04-22 Ben M. Leith , Ishwaree P. Neupane

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 explore the cosmological content of Salam-Sezgin six dimensional supergravity, and find a solution to the field equations in qualitative agreement with observation of distant supernovae, primordial nucleosynthesis abundances, and recent…

High Energy Physics - Phenomenology · Physics 2008-11-26 Luis Anchordoqui , Haim Goldberg , Satoshi Nawata , Carlos Nunez

We address three genuine phantom dark energy models where each of them induces the particular future events known as Big Rip, Little Rip and Little Sibling of the Big Rip. The background models are fully determined by a given dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-22 Amine Bouali , Imanol Albarran , Mariam Bouhmadi-López , Taoufik Ouali

A view is taken up whereby the non-singular Trautman-Kopczy\'nski big-bang creation of the Universe produced a highly torsional hot state at early stages of the cosmic evolution which particularly brought about the formation of a dark…

General Relativity and Quantum Cosmology · Physics 2023-01-30 J. G. Cardoso

We investigate the vacuum expectation values of the energy-momentum tensor and the fermionic condensate associated with a massive spinor field obeying the MIT bag boundary condition on a spherical shell in the global monopole spacetime. In…

High Energy Physics - Theory · Physics 2008-11-26 A. A. Saharian , E. R. Bezerra de Mello

We study the collision of two massive particles with non-zero intrinsic spin moving in the equatorial plane in the background of a Schwarzschild black hole surrounded by quintessential matter field (SBHQ). For the quintessential matter…

General Relativity and Quantum Cosmology · Physics 2020-09-17 Pankaj Sheoran , Hemwati Nandan , Eva Hackmann , Ulises Nucamendi , Amare Abebe

The self-gravitating gas in the Newtonian limit is studied in the presence of dark energy with a linear and constant equation of state. Entropy extremization associates to the isothermal Boltzmann distribution an effective density that…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-15 Zacharias Roupas , Minos Axenides , George Georgiou , Emmanuel N. Saridakis