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Related papers: Clockwork Inflation

200 papers

We propose a generalised de Sitter scale factor for the cosmology of early and late time universe, including single scalar field is called as inflaton. This form of scale factor has a free parameter $q$ is called as nonextensivity…

General Physics · Physics 2018-10-09 M. R. Setare , D. Momeni , V. Kamali , R. Myrzakulov

During single clock inflation, hidden fields (i.e. fields coupled to the inflaton only gravitationally) in their adiabatic vacua can ordinarily only affect observables through virtual effects. After renormalizing background quantities…

General Relativity and Quantum Cosmology · Physics 2019-01-30 Adrian del Rio , Ruth Durrer , Subodh P. Patil

It is shown that the squeezed limit of inflationary expectation values follows from reparametrization invariance of the wavefunction of the universe. This translates into a constraint on the longitudinal modes of functional derivatives of…

High Energy Physics - Theory · Physics 2018-03-28 Guilherme L. Pimentel

We investigate the tensor perturbation in the inflation model driven by a massive-scalar field in Eddington-inspired Born-Infeld gravity. For short wave-length modes, the perturbation feature is very similar to that of the usual chaotic…

General Relativity and Quantum Cosmology · Physics 2014-07-30 Inyong Cho , Hyeong-Chan Kim

We develop our recent suggestion that inflation may be made past eternal, so that there is no initial cosmological singularity or "beginning of time". Inflation with multiple vacua generically approaches a steady-state statistical…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Anthony Aguirre , Steven Gratton

The inflationary paradigm is an important cornerstone of the concordance cosmological model. However, standard inflation cannot fully address the transition from an early homogeneous and isotropic stage, to another one lacking such…

General Relativity and Quantum Cosmology · Physics 2015-12-08 Mauro Mariani , Gabriel R. Bengochea , Gabriel Leon

We study the effects of primordial magnetic fields on the inflationary potential in the context of a warm inflation scenario. The model, based on global supersymmetry with a new-inflation-type potential and a coupling between the inflaton…

High Energy Physics - Phenomenology · Physics 2014-10-08 Gabriella Piccinelli , Angel Sanchez , Alejandro Ayala , Ana Julia Mizher

One of the great triumphs of the inflationary model is the prediction of the flat power spectrum of the CMB fluctuation. The prediction is based on the assumption of the de-Sitter vacuum in the past infinity. However, the true past infinity…

General Relativity and Quantum Cosmology · Physics 2019-03-27 Tadashi Sasaki , Hisao Suzuki

We discuss the phenomenology of the minimal inflation scenario. We concentrate on two aspects: inflationary trajectories and particle production. Our findings can be summarized in two main results: first, that inflationary trayectories that…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Luis Alvarez-Gaume , Cesar Gomez , Raul Jimenez

We analyze the flow into inflation for generic "single-clock" systems, by combining an effective field theory approach with a dynamical-systems analysis. In this approach, we construct an expansion for the potential-like term in the…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-15 Feraz Azhar , David I. Kaiser

The effective approach is applied to the analysis of inflationary magnetogenesis. Rather than assuming a particular underlying description, all the generally covariant terms potentially appearing with four space-time derivatives in the…

High Energy Physics - Theory · Physics 2021-07-15 Massimo Giovannini

We discuss the gravitational waves (GW) in the context of vector inflation. We derive the action for tensor perturbations and find that tachyonic instabilities are present in most (but not all) of the inflationary models with large fields.…

Astrophysics · Physics 2009-03-20 Alexey Golovnev , Viatcheslav Mukhanov , Vitaly Vanchurin

Power spectra always play an important role in the theory of inflation. In particular, the ability to reproduce the galaxy matter power spectrum and the CMB temperature angular power spectrum coefficients to high accuracy is often…

General Relativity and Quantum Cosmology · Physics 2019-11-01 Herbert W. Hamber , Lu Heng Sunny Yu

The article presents modeling of inflationary scenarios for the first time in the $f(R,T)$ theory of gravity. We assume the $f(R,T)$ functional from to be $R + \eta T$, where $R$ denotes the Ricci scalar, $T$ the trace of the…

General Relativity and Quantum Cosmology · Physics 2020-08-03 Snehasish Bhattacharjee , J. R. L. Santos , P. H. R. S. Moraes , P. K. Sahoo

We discuss a new scenario for early cosmology, when inflationary de Sitter phase dynamically emergent. This genuine quantum effect occurs as a result of dynamics of the topologically nontrivial sectors in a (conjectured) strongly coupled…

High Energy Physics - Phenomenology · Physics 2014-08-13 Ariel R. Zhitnitsky

In construction of an inflationary model, one usually assumes that the matter sector of the gravitational action is minimally coupled to the background. It means that the matter (inflaton) part of the action is coupled with the same metric…

General Relativity and Quantum Cosmology · Physics 2021-05-25 Yousef Bisabr

We study a variant of the Chromo-Natural Inflation (CNI) mechanism in which the inflaton interacts only gravitationally with the CNI fields. Integrating out all the non-dynamical scalar fields of the model results in a coupling between the…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-04 Alexandros Papageorgiou , Marco Peloso , Caner Unal

We investigate a standard minimally-coupled scalar-field inflationary scenario, which is based on a new potential, with suitably generalized plateau features, that leads to extra small tensor-to-scalar ratios. In particular, we consider a…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-13 Gerasimos Kouniatalis , Emmanuel N. Saridakis

We study the problem of initial conditions for slow-roll inflation along a plateau-like scalar potential within the framework of fluctuation-dissipation dynamics. We consider, in particular, that inflation was preceded by a…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-09 Mar Bastero-Gil , Arjun Berera , Robert Brandenberger , Ian G. Moss , Rudnei O. Ramos , Joao G. Rosa

The methods of supergravity allow us to derive a multi-field F-term potential. Using this, we denote a generic and non-positive single-field F-term potential. We insert our theory into the scalar-gravity part of the $SU(2,1|1)$ invariant…

High Energy Physics - Theory · Physics 2021-04-12 Ugur Atli , Omer Guleryuz