English
Related papers

Related papers: Inflation by Alignment

200 papers

We study the primordial non-Gaussinity predicted from simple models of inflation with a linear potential and superimposed oscillations. This generic form of the potential is predicted by the axion monodromy inflation model, that has…

High Energy Physics - Phenomenology · Physics 2014-11-20 Steen Hannestad , Troels Haugboelle , Philip R. Jarnhus , Martin S. Sloth

We propose a novel mechanism for enhancing the primordial gravitational waves without significantly affecting the curvature perturbations produced during inflation. This is achieved due to non-linear sourcing of resonantly amplified scalar…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-05 Yi-Fu Cai , Jie Jiang , Misao Sasaki , Valeri Vardanyan , Zihan Zhou

We explore the mechanics of inflation in simplified extra-dimensional models involving an inflaton interacting with the Einstein-Maxwell system in two extra dimensions. The models are Goldilocks-like in that they are just complicated enough…

General Relativity and Quantum Cosmology · Physics 2016-08-31 C. P. Burgess , Jared J. H. Enns , Peter Hayman , Subodh P. Patil

If, after primordial inflation, the universe undergoes a relatively long reheating period, it could present a phase of matter domination supported by the oscillating inflaton field. During this epoch, small perturbations from the inflaton…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-30 Luis E. Padilla , Juan Carlos Hidalgo , Gabriel German

In negatively curved field spaces, inflation can be realised even in steep potentials. Hyperinflation invokes the `centrifugal force' of a field orbiting the hyperbolic plane to sustain inflation. We generalise hyperinflation by showing…

High Energy Physics - Theory · Physics 2019-05-22 Theodor Bjorkmo , M. C. David Marsh

Inflationary models driven by a large number of axion fields are discussed in the context of type IIB compactifications with N=1 supersymmetry. The inflatons arise as the scalar modes of the R-R two-forms evaluated on vanishing two-cycles…

High Energy Physics - Theory · Physics 2008-06-13 Thomas W. Grimm

Higgs inflation uses the gauge variant Higgs field as the inflaton. During inflation the Higgs field is displaced from its minimum, which results in associated Goldstone bosons that are apparently massive. Working in a minimally coupled…

High Energy Physics - Phenomenology · Physics 2012-07-31 Sander Mooij , Marieke Postma

Models of large-field inflation based on axion-like fields with shift symmetries can be simple and natural, and make a promising prediction of detectable primordial gravitational waves. The Weak Gravity Conjecture is known to constrain the…

High Energy Physics - Theory · Physics 2016-01-27 Ben Heidenreich , Matthew Reece , Tom Rudelius

We reexamine inflation due to a constrained inflaton in the model of a complex scalar. Inflaton evolves along a spiral-like valley of special scalar potential in the scalar field space just like single field inflation. Sub-Planckian…

High Energy Physics - Phenomenology · Physics 2015-12-02 Romy H. S. Budhi , Shoichi Kashiwase , Daijiro Suematsu

The original axion natural inflation model predicts a tensor-to-scalar ratio exceeding experimental limits. Conversely, in aligned axion inflation, inflation can proceed along trajectories emerging from near a saddle point of the two-field…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-21 Federico Greco

In this work, we show the effect of the non-minimal coupling $\xi \phi^2 R$ on the inflationary parameters by considering the single-field inflation and present the inflationary predictions of the appealing potential for the particle…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-03 Nilay Bostan

Supergravity models of natural inflation and its generalizations are presented. These models are special examples of the class of supergravity models proposed in arXiv:1008.3375 and arXiv:1011.5945, which have a shift symmetric K\"ahler…

High Energy Physics - Theory · Physics 2014-09-05 Renata Kallosh , Andrei Linde , Bert Vercnocke

Slow-roll inflation is a successful paradigm. However we find that even a small coupling of the inflaton to other light fields can dramatically alter the dynamics and predictions of inflation. As an example, the inflaton can generically…

High Energy Physics - Phenomenology · Physics 2023-09-19 Kim V. Berghaus , Peter W. Graham , David E. Kaplan

Inflation is a highly favoured theory for the early Universe. It is compatible with current observations of the cosmic microwave background and large scale structure and is a driver in the quest to detect primordial gravitational waves. It…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-19 Tomás Sousa , Deaglan J. Bartlett , Harry Desmond , Pedro G. Ferreira

We construct explicit models of multi-field inflation in which the primordial metric fluctuations do not necessarily obey Gaussian statistics. These models are realizations of mechanisms in which non-Gaussianity is first generated by a…

Astrophysics · Physics 2008-11-26 Francis Bernardeau , Jean-Philippe Uzan

A safe way to reheat the universe, in models of natural and quadratic inflation, is through shift symmetric couplings between the inflaton $\phi$ and the Standard Model (SM), since they do not generate loop corrections to the potential…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-04 Ricardo Z. Ferreira , Alessio Notari

Simple monomial inflationary scenarios have been ruled out by recent observations. In this work we revisit the next simplest scenario, a single--field model where the scalar potential is a polynomial of degree four which features a concave…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-14 Manuel Drees , Yong Xu

We propose a model for inflation consisting of an axionic scalar field coupled to a set of three non-Abelian gauge fields. Our model's novel requirement is that the gauge fields begin inflation with a rotationally invariant vacuum…

High Energy Physics - Theory · Physics 2012-07-06 Peter Adshead , Mark Wyman

We investigate, in a model-independent way, the conditions required to obtain a satisfactory model of extended inflation in which inflation is brought to an end by a first-order phase transition. The constraints are that the correct present…

Astrophysics · Physics 2009-10-28 Anne M Green , Andrew R Liddle

We present a series of theoretical constraints on the potentially viable inflation models that might yield a blue spectrum for primordial tensor perturbations. By performing a detailed dynamical analysis we show that, while there exists…

High Energy Physics - Theory · Physics 2015-12-09 Yi-Fu Cai , Jinn-Ouk Gong , Shi Pi , Emmanuel N. Saridakis , Shang-Yu Wu