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Related papers: Towards Natural Inflation in String Theory

200 papers

We propose a multi-natural inflation model in which the single-field inflaton potential consists of two or more sinusoidal potentials that are comparable in size, but have different periodicity with a possible non-zero relative phase. The…

High Energy Physics - Phenomenology · Physics 2014-05-30 Michael Czerny , Fuminobu Takahashi

In this PhD thesis, we investigate generic features of inflation which are strictly related to fundamental aspects of UV-physics scenarios, such as string theory or supergravity. After a short introduction to standard and inflationary…

High Energy Physics - Theory · Physics 2016-07-06 Marco Scalisi

Starting from the idea of realising constant roll inflation in string theory we develop the constant roll formalism for two scalar fields. We derive the two-field potential which is compatible with a constant roll regime and discuss…

High Energy Physics - Theory · Physics 2019-11-13 Andrei Micu

In this paper we propose a two-field model of warm inflation motivated from a heterotic string construction. The model contains an axion and a dilaton-like field. We show that while warm inflation can take place in the axion-field…

Inflationary potentials are investigated for specific models in type IIB string theory via flux compactification. As concrete models, we investigate several cases where the internal spaces are weighted projective spaces. The models we…

High Energy Physics - Theory · Physics 2011-03-15 Sunggeun Lee , Soonkeon Nam

We consider the possibility of realizing inflation in nonlocal field theories containing infinitely many derivatives. Such constructions arise naturally in string field theory and also in a number of toy models, such as the p-adic string.…

High Energy Physics - Theory · Physics 2010-11-02 Neil Barnaby

We investigate the axion inflation model derived by poly-instanton effects in type II superstring theories. Poly-instanton effects are instanton effects corrected by another instanton and it can generate the modulus-axion potential with the…

High Energy Physics - Phenomenology · Physics 2017-07-19 Tatsuo Kobayashi , Shohei Uemura , Junji Yamamoto

We consider models of inflection point inflation. The main drawback of such models is that they suffer from the overshoot problem. Namely the initial condition should be fine tuned to be near the inflection point for the universe to…

High Energy Physics - Theory · Physics 2010-04-30 Nissan Itzhaki , Ely D. Kovetz

Slow-roll inflation requires the inflaton field to have an exceptionally flat potential, which combined with measurements of the scale of inflation demands some degree of fine-tuning. Alternatively, the flatness of the potential could be…

High Energy Physics - Phenomenology · Physics 2015-06-23 Djuna Croon , Veronica Sanz

Recently we introduced an inflationary setup in which the inflaton fields are matrix valued scalar fields with a generic quartic potential, M-flation. In this work we study the landscape of various inflationary models arising from…

High Energy Physics - Theory · Physics 2010-05-12 Amjad Ashoorioon , Hassan Firouzjahi , Mohammmad Mahdi Sheikh-Jabbari

A pseudo Nambu-Goldstone boson (such as an axion-like particle) is a theoretically well-motivated inflaton as it features a naturally flat potential (natural inflation). This is because Goldstone's theorem protects its potential from…

High Energy Physics - Phenomenology · Physics 2021-10-08 Alberto Salvio

In this work, we propose a string-inspired two fields inflation model to address the fine-tuning problem that the standard inflation model suffers. The fast-rolling tachyon $\mathcal{T}$ originated from the D-brane and anti-D-brane pair…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-01 Changhong Li , Hao Gong , Yeuk-kwan Edna Cheung

We discuss string corrections to the effective potential in various models of brane inflation. These corrections contribute to the mass of the inflaton candidate and may improve its slow-roll properties. In particular, in orientifold string…

High Energy Physics - Theory · Physics 2007-05-23 Marcus Berg , Michael Haack , Boris Kors

We study an inflationary model where two decoupled string axions drive inflation. The number of e-folds is dependent on the energy scale and the decay constant, but is almost independent of the angular component in spite of the rich…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jinn-Ouk Gong

We consider "new inflation" inflationary models at small fields, embedded in minimal ${\cal N}=1$ supergravity with a single chiral superfield. Imposing a period of inflation compatible with experiment severely restricts possible models,…

High Energy Physics - Theory · Physics 2016-10-12 Heliudson Bernardo , Horatiu Nastase

We study the problem of obtaining de Sitter and inflationary vacua from dimensional reduction of double field theory (DFT) on nongeometric string backgrounds. In this context, we consider a new class of effective potentials that admit…

High Energy Physics - Theory · Physics 2016-05-05 Falk Hassler , Dieter Lust , Stefano Massai

The topic of this talk is a new inflationary model in the context of Type IIB string compactifications called Loop Blow-Up Inflation, presented in arXiv:2403.04831. The original Blow-Up Inflation model, whose potential was purely…

High Energy Physics - Theory · Physics 2025-02-24 Luca Brunelli

In this talk, I shall focus on theories beyond the Standard Model which predict massive neutrinos. Hybrid inflation emerges naturally in these theories: the slow-rolling inflaton field is a gauge singlet which couples with a GUT Higgs field…

High Energy Physics - Phenomenology · Physics 2007-05-23 Rachel Jeannerot

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

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