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Related papers: Gauss-Bonnet Inflation after Planck2018

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In this short note we present the dynamics of a general scalar-tensor model, and in particular a scalar Einstein-Gauss-Bonnet model with a non-minimal coupling between gravity and the kinetic term of the scalar field. For the sake of…

General Relativity and Quantum Cosmology · Physics 2021-10-04 Fotis Fronimos

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 consider an extension of Higgs inflation in which the Higgs field is coupled to the Gauss-Bonnet term. Working solely in the Jordan frame, we firstly recover the standard predictions of Higgs inflation without a Gauss-Bonnet term. We…

High Energy Physics - Phenomenology · Physics 2016-05-23 Carsten van de Bruck , Chris Longden

We study a particular Galileon inflation in the light of Planck2015 observational data in order to constraint the model parameter space. We study the spectrum of the primordial modes of the density perturbations by expanding the action up…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Kosar Asadi , Kourosh Nozari

In this work we investigate several Einstein-Gauss-Bonnet models that are compatible with the GW170817 event, the Atacama Cosmology Telescope data and the BICEP/Keck updated Planck constraints on the tensor-to-scalar ratio. We consider two…

General Relativity and Quantum Cosmology · Physics 2025-08-01 S. D. Odintsov , V. K. Oikonomou

We investigate the influence on the inflationary predictions from the reheating processes characterized by the $e$-folding number $N_{\mathrm{reh}}$ and the effective equation-of-state parameter $w_{\mathrm{reh}}$ during the reheating…

General Relativity and Quantum Cosmology · Physics 2015-09-10 Rong-Gen Cai , Zong-Kuan Guo , Shao-Jiang Wang

By adopting the intermediate and power-law scale factors, we study the tachyon inflation with constant sound speed. We perform some numerical analysis on the perturbation and non-gaussianity parameters in this model and compare the results…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-05 Narges Rashidi

We consider two non-canonical scalar fields (tachyon and DBI) with E-model type of the potential. We study cosmological inflation in these models to find possible $\alpha$-attractors. We show that similar to the canonical scalar field case,…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-23 Narges Rashidi , Kourosh Nozari

The constraints on a general form of the power-law potential and the dissipation coefficient in the framework of warm single field inflation imposed by Planck data will be investigated. {By Considering a quasi-static Universe, besides a…

General Relativity and Quantum Cosmology · Physics 2019-12-03 Zahra Ghadiri , Abdollah Refaei , Ali Aghamohammadi , Haidar Sheikhahmadi

In this paper we study the reheating constraints on inflationary models considering perturbatively decaying inflaton. Important difference with the existing analysis is the inclusion of explicit decaying dynamics of inflaton during…

High Energy Physics - Theory · Physics 2020-11-05 Debaprasad Maity

In this work we introduce a new plateau-like inflationary model including a quadratic scalar potential coupled non-minimally to gravity. This potential has a dominant constant energy density at early times which can realize successful…

High Energy Physics - Theory · Physics 2015-11-30 Mehdi Eshaghi , Moslem Zarei , Nematollah Riazi , Ahmad Kiasatpour

Inflationary reheating via resonant production of non-minimally coupled scalar particles with only gravitational coupling is shown to be extremely strong, exhibiting a negative coupling instability for $\xi < 0$ and a wide resonance decay…

High Energy Physics - Phenomenology · Physics 2014-11-17 Bruce A. Bassett , Stefano Liberati

Gauge-flation is a recently proposed model in which inflation is driven solely by a non-Abelian gauge field thanks to a specific higher order derivative operator. The nature of the operator is such that it does not introduce ghosts. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Ryo Namba , Emanuela Dimastrogiovanni , Marco Peloso

Recent analyses combining Atacama Cosmology Telescope (ACT) data with other cosmological datasets report a higher scalar spectral index $n_s$, creating tension with a wide range of inflationary models. Since a Gauss-Bonnet term with a…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-03 Yigan Zhu , Qing Gao , Yungui Gong , Zhu Yi

With the Planck 2015 result, most of the well known canonical large field inflation models turned out to be strongly disfavored. Axion inflation is one of such models which is becoming marginalized with the increasing precession of CMB…

High Energy Physics - Phenomenology · Physics 2018-08-02 Debaprasad Maity , Pankaj Saha

Recent observations of the cosmic microwave background (CMB) indicate that a successful theory of cosmological inflation needs to have flat potential of the inflaton scalar field. Realizing the inflaton to be a pseudo-Nambu Goldstone boson…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-15 Sukannya Bhattacharya , Mayukh R. Gangopadhyay

We present projections for reconstruction of the inflationary potential expected from ESA's upcoming Planck Surveyor CMB mission. We focus on the effects that tensor perturbations and the presence of non-Gaussianities have on reconstruction…

Astrophysics · Physics 2009-11-13 Brian A. Powell , Konstantinos Tzirakis , William H. Kinney

We focus on the inflationary predictions of $\beta$-exponential potential models, in which the inflaton is a representation of the field delineating the size of extra-dimension. Since it offers a well-motivated starting point for the study…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-17 Nilay Bostan , Rafid H. Dejrah

We analyze the latest cosmic microwave background (CMB) constraints on the scalar spectral index $n_s$ and tensor-to-scalar ratio $r$ from Planck 2018, BICEP/Keck 2018, the Atacama Cosmology Telescope Data Release 6 (ACT DR6), and the South…

High Energy Physics - Phenomenology · Physics 2025-10-22 John Ellis , Marcos A. G. Garcia , Keith A. Olive , Sarunas Verner

Tachyon inflation is one of the most attractive models of noncannonical inflation motivated by string theory. In this work we revisit the constraints on tachyon inflation with inverse $\cosh$ potential and exponential potential considering…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-05 Akhilesh Nautiyal