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Related papers: Supergravity Inflation Free from Harmful Relics

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We discuss phenomenological viability of a novel inflationary model in the minimal gauge mediated supersymmetry breaking scenario. In this model, cosmic inflation is realized in the flat direction along the messenger supermultiplets and a…

High Energy Physics - Phenomenology · Physics 2021-11-10 Shinsuke Kawai , Nobuchika Okada

We show that maximally helical hypermagnetic fields produced during pseudoscalar inflation can generate the observed baryon asymmetry of the universe via the B+L anomaly in the Standard Model. We find that most of the parameter space of…

High Energy Physics - Theory · Physics 2015-11-11 Mohamed M. Anber , Eray Sabancilar

We propose a scenario for inflation based upon the braneworld picture, in which high-energy corrections to the Friedmann equation permit inflation to take place with potentials ordinarily too steep to sustain it. Inflation ends when the…

Astrophysics · Physics 2009-10-31 Edmund J Copeland , Andrew R Liddle , James E Lidsey

We investigate the cosmological inflation in a class of supergravity models that are generalizations of non-supersymmetric $R^2$ models. Although such models have been extensively studied recently, especially after the launch of the PLANCK…

High Energy Physics - Theory · Physics 2015-06-23 G. A. Diamandis , B. C. Georgalas , K. Kaskavelis , P. Kouroumalou , A. B. Lahanas , G. Pavlopoulos

We explore a model of inflation where the inflaton mass-squared is generated at a high scale by gravity-mediated soft supersymmetry breaking, and runs at lower scales to the small value required for slow-roll inflation. The running is…

High Energy Physics - Phenomenology · Physics 2009-10-31 Laura Covi , David H. Lyth , Leszek Roszkowski

We discuss supergravity inflation in braneworld cosmology for the class of potentials $V(\phi)=\alpha \phi^n\rm{exp}(-\beta^m \phi^m)$ with $m=1,~2$. These minimal SUGRA models evade the $\eta$ problem due to a broken shift symmetry and can…

High Energy Physics - Theory · Physics 2023-08-11 Mudassar Sabir , Waqas Ahmed , Yungui Gong , Shan Hu , Tianjun Li , Lina Wu

We present an introduction to cosmic inflation in the framework of Palatini gravity, which provides an intriguing alternative to the conventional metric formulation of gravity. In the latter, only the metric specifies the spacetime…

General Relativity and Quantum Cosmology · Physics 2025-01-23 Ioannis D. Gialamas , Alexandros Karam , Thomas D. Pappas , Eemeli Tomberg

Models of inflation in which the Higgs field is non-minimally coupled to gravity lead, after a recaling of the metric, to a complicated expression for the potential of the inflaton field. Nevertheless, this potential produces the desired…

High Energy Physics - Theory · Physics 2022-06-08 Noureddine Mohammedi

We develop generalized no-scale supergravity models of inflation, and then study the corresponding cosmological predictions as well as the formation of primordial black holes (PBHs) and scalar-induced gravitational waves (SIGWs). With a new…

General Relativity and Quantum Cosmology · Physics 2024-07-22 Lina Wu , Jin-Ke Shen , Tianjun Li , Junle Pei

We study the possibility that particle production during inflation could source observable gravity waves on scales relevant for Cosmic Microwave Background experiments. A crucial constraint on such scenarios arises because particle…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Neil Barnaby , Jordan Moxon , Ryo Namba , Marco Peloso , Gary Shiu , Peng Zhou

We have recently proposed attractor models for modulus fixing, inflation, supersymmetry breaking and dark energy based on no-scale supergravity. In this paper we develop phenomenological and cosmological aspects of these no-scale attractor…

High Energy Physics - Phenomenology · Physics 2020-09-02 John Ellis , Dimitri V. Nanopoulos , Keith A. Olive , Sarunas Verner

Most models of inflation have small parameters, either to guarantee sufficient inflation or the correct magnitude of the density perturbations. In this paper we show that, in supersymmetric theories with weak scale supersymmetry breaking,…

High Energy Physics - Phenomenology · Physics 2009-09-15 Lisa Randall , Marin Soljacic , Alan Guth

(Abridged) We study dissipative inflation in the regime where the dissipative term takes a specific form, \Gamma=\Gamma(\phi), analyzing two models in the weak and strong dissipative regimes with a SUSY breaking potential. After developing…

Astrophysics · Physics 2011-05-12 Lisa M. H. Hall , Hiranya V. Peiris

We study models of modular inflation of the form expected to arise from low energy effective actions of superstring theories. We argue on general grounds that the most likely models of modular slow-roll inflation are small field models in…

High Energy Physics - Theory · Physics 2009-12-15 Ido Ben-Dayan , Ram Brustein , Senarath P. de Alwis

We review our recent results on dark matter from Starobinsky supergravity. In this context, a natural candidate for Cold Dark Matter is the gravitino. On the other hand, assuming the supersymmetry broken at scales much higher than the…

General Relativity and Quantum Cosmology · Physics 2017-05-24 Andrea Addazi , Maxim Yu. Khlopov

Many models of supersymmetry breaking involve particles with weak scale mass and Planck mass suppressed couplings. Coherent production of such particles in the early universe destroys the successful predictions of nucleosynthesis. We show…

High Energy Physics - Phenomenology · Physics 2009-09-15 Lisa Randall , Scott Thomas

Supersymmetry is the most natural framework for physics above the TeV scale, and the corresponding framework for early-Universe cosmology, including inflation, is supergravity. No-scale supergravity emerges from generic string…

High Energy Physics - Phenomenology · Physics 2016-04-27 John Ellis , Marcos A. G. Garcia , Dimitri V. Nanopoulos , Keith A. Olive

Modular cosmology is plagued by overproduction of unwanted relics, gravitinos and especially moduli, at relatively low energy scales. Thermal inflation provides a compelling solution to this moduli problem, but invalidates most baryogenesis…

High Energy Physics - Phenomenology · Physics 2008-11-26 Donghui Jeong , Kenji Kadota , Wan-Il Park , Ewan D. Stewart

We reconsider the Polonyi problem in gravity-mediation models for supersymmetry (SUSY) breaking. It has been argued that there is no problem in the dynamical SUSY breaking scenarios, since the Polonyi field acquires a sufficiently large…

High Energy Physics - Phenomenology · Physics 2009-11-11 M. Ibe , Y. Shinbara , T. T. Yanagida

Axion inflation entails a coupling of the inflaton field to gauge fields through the Chern-Simons term. This results in a strong gauge field production during inflation, which backreacts on the inflaton equation of motion. Here we show that…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-13 Valerie Domcke , Veronica Guidetti , Yvette Welling , Alexander Westphal
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