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Related papers: Comment on Asymptotically Safe Inflation

200 papers

In this work, we explored warm inflation in the background of $f(R,T)$ gravity in the strong dissipation regime. Considering scalar field for FLRW universe, we derived modified field equations. We then deduced slow-roll parameters under…

General Relativity and Quantum Cosmology · Physics 2023-11-07 Biswajit Deb , Sabina Yeasmin , Atri Deshamukhya

We examine a scalar-tensor model of gravity that is globally scale-invariant. When adapted to a spatially flat Robertson-Walker metric, the equations of motion describe a dynamical system that flows from an unstable de Sitter space to a…

General Relativity and Quantum Cosmology · Physics 2023-06-27 Massimiliano Rinaldi , Chiara Cecchini , Anish Ghoshal , Debangshu Mukherjee

The stable version of the anomaly-induced inflation does not need a fine tuning and leads to sufficient expansion of the Universe. The non-stable version (Starobinsky model) provides the graceful exit to the FRW phase. We indicate the…

High Energy Physics - Phenomenology · Physics 2009-02-25 Ilya L. Shapiro

We have explicitly demonstrated that scalar coupled Gauss-Bonnet gravity in four dimension can have non-trivial effects on the early inflationary stage of our universe. In particular, we have shown that the scalar coupled Gauss-Bonnet term…

General Relativity and Quantum Cosmology · Physics 2018-11-13 Sumanta Chakraborty , Tanmoy Paul , Soumitra SenGupta

We study a supergravity model of inflation with R-symmetry and a single scalar field, the inflaton, slowly rolling away from the origin. The scales of inflation can be as low as the supersymmetry breaking scale of 10^10 GeV or even the…

High Energy Physics - Theory · Physics 2009-10-31 G. German , A. de la Macorra , M. Mondragon

Power spectra play an important role in the theory of inflation, and their ability to reproduce current observational data to high accuracy is often considered a triumph of inflation, largely because of a lack of credible alternatives. In…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-21 Herbert W. Hamber , Lu Heng Sunny Yu , Hasitha E. Pituwala Kankanamge

Phenomenologically appealing supersymmetric grand unified theories have large gauge representations and thus are not asymptotically free. Their ultraviolet validity is limited by the appearance of a Landau pole well before the Planck scale.…

High Energy Physics - Theory · Physics 2017-02-01 Borut Bajc , Francesco Sannino

We study the short distance behaviour of euclidean quantum gravity in the light of Weinberg's asymptotic safety scenario. Implications of a non-trivial ultraviolet fixed point are reviewed. Based on an optimised renormalisation group, we…

High Energy Physics - Theory · Physics 2009-11-11 Daniel F. Litim

We consider the renormalization group improvement in the theory of the Standard Model Higgs boson playing the role of an inflaton with a strong non-minimal coupling to gravity. It suggests the range of the Higgs mass $135.6 {\rm GeV}…

High Energy Physics - Phenomenology · Physics 2009-12-08 A. O. Barvinsky , A. Yu. Kamenshchik , C. Kiefer , A. A. Starobinsky , C. Steinwachs

Ultra slow-roll inflation has recently been used to challenge the non-Gaussianity consistency relation. We show that this inflationary scenario belongs to a one parameter class of models and we study its properties and observational…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Jerome Martin , Hayato Motohashi , Teruaki Suyama

Building a consistent Quantum Theory of Gravity is one of the most challenging aspects of modern theoretical physics. In the past couple of years, new attempts have been made along the path of ``asymptotic safety'' through the use of Exact…

High Energy Physics - Theory · Physics 2009-11-10 Daniele Perini

Using the Einstein-Hilbert approximation of asymptotically safe quantum gravity we present a consistent renormalization group based framework for the inclusion of quantum gravitational effects into the cosmological field equations. Relating…

High Energy Physics - Theory · Physics 2009-11-11 M. Reuter , F. Saueressig

We present the first quantum field theory model of inflation that is renormalizable in the matter sector, with a super-Hubble inflaton mass and sub-Planckian field excursions, which is thus technically natural and consistent with a…

High Energy Physics - Phenomenology · Physics 2021-01-11 Mar Bastero-Gil , Arjun Berera , Rudnei O. Ramos , João G. Rosa

We compute the corrections to the primordial power spectrum that should arise in realistic inflationary scenarios if there exists a generic covariant ultraviolet (UV) cutoff, as commonly motivated by considerations of quantum gravity. The…

High Energy Physics - Theory · Physics 2023-05-01 Aidan Chatwin-Davies , Achim Kempf , Petar Simidzija

Because the inflationary mechanism is extremely sensitive to UV-physics, the construction of theoretically robust models of inflation provides a unique window on Planck-scale physics. We review efforts to use an axion with a shift symmetry…

High Energy Physics - Theory · Physics 2015-06-15 Enrico Pajer , Marco Peloso

Asymptotic safety is a theoretical proposal for the ultraviolet completion of quantum field theories, in particular for quantum gravity. Significant progress on this program has led to a first characterization of the Reuter fixed point.…

General Relativity and Quantum Cosmology · Physics 2020-04-16 Alfio Bonanno , Astrid Eichhorn , Holger Gies , Jan M. Pawlowski , Roberto Percacci , Martin Reuter , Frank Saueressig , Gian Paolo Vacca

Recent studies of the ultraviolet behaviour of pure gravity suggest that it admits a non-Gaussian attractive fixed point, and therefore that the theory is asymptotically safe. We consider the effect on this fixed point of massless minimally…

High Energy Physics - Theory · Physics 2009-11-07 Roberto Percacci , Daniele Perini

We propose a model for cosmic inflation which is based on an effective description of strongly interacting, nonsupersymmetric matter within the framework of dynamical abelian projection and centerization. The underlying gauge symmetry is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Ralf Hofmann , Mathias Th. Keil

We investigate the inflation and reheating phenomenology in scalar-Einstein-Gauss-Bonnet theory of gravity where a scalar field non-minimally couples with the Gauss-Bonnet (GB) curvature term. Regarding the inflationary phenomenology, we…

General Relativity and Quantum Cosmology · Physics 2023-05-31 Sergei D. Odintsov , Tanmoy Paul

The present work examines the possibility of warm inflationary paradigm in the modified gravity theory with fractal geometry. By choosing the normal fluid as radiation fluid and the effective fluid (with the extra term in modified field…

General Relativity and Quantum Cosmology · Physics 2022-04-14 A. Bose , S. Chakraborty