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Related papers: Closing in on $\alpha$-attractors

200 papers

We study inflation in the $\alpha-$attractor model under a non-slow-roll dynamics with an ansatz proposed by Gong \& Sasaki \cite{Gong:2015ypa} of assuming $N=N\left(\phi\right)$. Under this approach, we construct a class of local shapes of…

General Relativity and Quantum Cosmology · Physics 2017-11-21 K. Sravan Kumar , João Marto , Paulo Vargas Moniz , Suratna Das

We consider the CMB constraints on reheating and dark matter parameter space for a specific plateau type inflationary model. The plateau inflationary models which are currently most favored models from data can be well approximated by a…

High Energy Physics - Phenomenology · Physics 2019-06-07 Debaprasad Maity , Pankaj Saha

We study the intermediate tachyon inflation in an anisotropic background. By using the Friedmann equations obtained in the anisotropic geometry, we obtain the slow-roll parameters in the tachyon model. The presence of the anisotropic…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-05 Narges Rashidi

We show explicitly how the T model, E model, and Hilltop inflations are obtained from the general scalar-tensor theory of gravity with arbitrary conformal factors in the strong coupling limit. We argue that $\xi$ attractors can give any…

General Relativity and Quantum Cosmology · Physics 2016-12-07 Zhu Yi , Yungui Gong

It is plausible that the scalar density perturbations are created by a relatively low scale model of inflation which predicts the CMB anisotropy and excites Standard Model baryon and cold dark matter, but negligible gravity waves.…

Astrophysics · Physics 2008-04-03 Rouzbeh Allahverdi , Anupam Mazumdar , Tuomas Multamaki

Optimisation of heat engines at the micro-scale has applications in biological and artificial nano-technology, and stimulates theoretical research in non-equilibrium statistical physics. Here we consider non-interacting overdamped particles…

Soft Condensed Matter · Physics 2021-06-02 Giulia Gronchi , Andrea Puglisi

In this work we study one of the most appealing string theory-motivated models, we present a tachyonic inflationary model in the recently proposed symmetric teleparallel framework, and examine constraints on tachyon inflation with the…

General Relativity and Quantum Cosmology · Physics 2023-02-27 K. El Bourakadi , Z. Sakhi , M. Bennai

In this work we study static neutron stars in the context of several inflationary models which are popular in cosmology. These inflationary models are non-minimally coupled scalar theories which yield a viable inflationary phenomenology in…

General Relativity and Quantum Cosmology · Physics 2023-05-31 S. D. Odintsov , V. K. Oikonomou

We present constraints on canonical single-field inflation derived from WMAP five year, ACBAR, QUAD, BICEP data combined with the halo power spectrum from SDSS LRG7. Models with a non-scale-invariant spectrum and a red tilt n_s < 1 are now…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-30 Fabio Finelli , Jan Hamann , Samuel M. Leach , Julien Lesgourgues

Inflation produces nearly Harrison-Zel'dovich scalar and tensor perturbation spectra which lead to anisotropy in the cosmic microwave background (CMB). The amplitudes and shapes of these spectra can be parametrized by $Q_S^2$, $r\equiv…

Astrophysics · Physics 2009-10-28 Lloyd Knox

The potential $V(\phi)=\lambda \phi^{n}$ is responsible for the inflation of the universe as scalar field $\phi$ oscillates quickly around some point where $V(\phi)$ has a minimum. The end of this stage has an important role on the further…

General Relativity and Quantum Cosmology · Physics 2019-08-14 B. Ghayour

We investigate the anisotropies in the cosmic microwave background in a class of models which possess a positive cosmic energy density but negative pressure, with a constant equation of state w = p/rho < -1. We calculate the temperature and…

Astrophysics · Physics 2009-07-09 A. E. Schulz , Martin White

We consider a supersymmetric grand unified model which leads to hybrid inflation and solves the strong CP and mu problems via a Peccei-Quinn symmetry, with the Peccei-Quinn field acting as a curvaton generating together with the inflaton…

High Energy Physics - Phenomenology · Physics 2009-11-11 George Lazarides

We perform the finite-temperature determinant quantum Monte Carlo simulation for the attractive Hubbard model on the half-filled bilayer square lattice. Recent progress on optical lattice experiments lead us to investigate various…

Strongly Correlated Electrons · Physics 2022-11-22 Yogeshwar Prasad

The inflationary reheating phase begins when accelerated expansion ends. As all Standard Model particles are coupled to gravity, gravitational interactions will lead to particle production. This includes the thermal bath, dark matter and…

High Energy Physics - Phenomenology · Physics 2024-02-08 Gongjun Choi , Wenqi Ke , Keith A. Olive

In this work, we solved the scalar and tensor perturbation equations numerically and using the improved uniform approximation method together with the third-order phase-integral method, for the $\alpha$-attractor inflationary model. This…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-13 Jordan Zambrano , Miguel Agama , Marcos Garzón , Werner Bramer-Escamilla , Clara Rojas , Teófilo Vargas

The nonlinear interaction between one graviton and two scalars is enhanced in specific inflationary models, potentially leading to distinguishable signatures in the bispectrum of the cosmic microwave background (CMB) anisotropies. We…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-15 Maresuke Shiraishi , Michele Liguori , James R. Fergusson

A new inflationary scenario whose exponential potential $V(\Phi)$ has a quadratic dependence on the field $\Phi$ in addition to the standard linear term is confronted with the tree-year observations of the Wilkinson-Microwave Anisotropy…

Astrophysics · Physics 2009-06-23 F. C. Carvalho , J. S. Alcaniz , J. A. S. Lima , R. Silva

We investigate the implications of recent CMB observations for Higgs-Starobinsky inflationary models and their associated reheating dynamics, utilizing data from ACT DR6, Planck 2018, BICEP/Keck 2018, and DESI, collectively referred to as…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-03 Md Riajul Haque , Sourav Pal , Debarun Paul

We investigate the two-stage inflation regime in the theory of hybrid cosmological $\alpha$-attractors. The spectrum of inflationary perturbations is compatible with the latest Planck/BICEP/Keck results, thanks to the attractor properties…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-11 Matteo Braglia , Andrei Linde , Renata Kallosh , Fabio Finelli