中文
相关论文

相关论文: Observational constraints on tachyon and DBI infla…

200 篇论文

We re-examine the importance of slow-roll corrections during the evolution of cosmological perturbations in models of multi-field inflation. We find that in many instances the presence of light degrees of freedom leads to situations in…

宇宙学与河外天体物理 · 物理学 2012-02-28 Anastasios Avgoustidis , Sera Cremonini , Anne-Christine Davis , Raquel H. Ribeiro , Krzysztof Turzynski , Scott Watson

We develop a method to compute the slow-roll expansion for the Hubble parameter in inflationary models in a flat Friedmann-Lema\^itre-Robertson-Walker spacetime that is applicable to a wide class of potentials including monomial,…

广义相对论与量子宇宙学 · 物理学 2024-10-07 Gabriel Álvarez , Elena Medina

We investigate the observational signatures of quantum cosmology in the Cosmic Microwave Background data provided by Planck collaboration. We apply the warm inflationary paradigm with a tachyon scalar field to the loop quantum cosmology. In…

广义相对论与量子宇宙学 · 物理学 2018-04-25 Vahid Kamali , Spyros Basilakos , Ahmad Mehrabi , Meysam Motaharfar , Erfan Massaeli

This study extended noncanonical warm inflation to the nonminimal derivative coupling scenario. The fundamental equations, including the evolution equations and the slow roll equations of this new framework, were derived. The enlarged…

广义相对论与量子宇宙学 · 物理学 2024-12-05 Xiao-Min Zhang , Run-Qing Zhao , Zhi-peng Peng , Xi-Bin Li , Yun-Cai Feng , Peng-Cheng Chu , Yi-Hang Xing

We consider inflationary models with the inflaton coupled to the Gauss-Bonnet term assuming a special relation $\delta_1=2\lambda\epsilon_1$ between the two slow-roll parameters $\delta_1$ and $\epsilon_1$. For the slow-roll inflation, the…

广义相对论与量子宇宙学 · 物理学 2018-10-19 Zhu Yi , Yungui Gong , Mudassar Sabir

We point out that in the large field regime, the recently proposed superconformal D-term inflation model coincides with the Starobinsky model. In this regime, the inflaton field dominates over the Planck mass in the gravitational kinetic…

高能物理 - 理论 · 物理学 2015-06-16 W. Buchmuller , V. Domcke , K. Kamada

Single field inflationary models are investigated within Palatini quadratic gravity represented by $R+\alpha R^2$ along with a non-minimal coupling of the form $f(\phi) R$ between the inflaton field $\phi$ and the gravity. The treatment is…

宇宙学与河外天体物理 · 物理学 2023-03-15 Mahmoud AlHallak

We study a model of inflation based on $\mathcal{N}=1$ supergravity essentially depending on one effective parameter. Under a field transformation we show that this model turns out to be equivalent to a previously studied supergravity model…

宇宙学与河外天体物理 · 物理学 2020-01-13 Gabriel Germán , Juan Carlos Hidalgo , Francisco X. Linares Cedeño , Ariadna Montiel , J. Alberto Vázquez

We show that the non-minimal coupling of tachyon field to the scalar curvature, as proposed by Piao et al, with the chosen coupling parameter does not produce the effective potential where the tachyon field can roll down from T=0 to large…

高能物理 - 理论 · 物理学 2010-11-19 Pravabati Chingangbam , Sudhakar Panda , Atri Deshamukhya

We study models of modular inflation of the form expected to arise from low energy effective actions of superstring theories. We argue on general grounds that the most likely models of modular slow-roll inflation are small field models in…

高能物理 - 理论 · 物理学 2009-12-15 Ido Ben-Dayan , Ram Brustein , Senarath P. de Alwis

The PLANCK collaboration has determined values for the spectral parameters of the CMB radiation, namely the spectral index $n_s$, its running $\alpha_s$, the running of the running $\beta_s$, using a growing body of measurements of CMB…

广义相对论与量子宇宙学 · 物理学 2016-10-12 Jaume Amorós , Jaume de Haro

A model of tachyon inflation is proposed in the framework of holographic cosmology. The model is based on a holographic braneworld scenario with a D3-brane located at the holographic boundary of an asymptotic ADS$_5$ bulk. The tachyon field…

广义相对论与量子宇宙学 · 物理学 2019-09-04 Neven Bilic , Dragoljub D. Dimitrijevic , Goran S. Djordjevic , Milan Milosevic , Marko Stojanovic

We take a pragmatic, model independent approach to single field slow-roll inflation by imposing conditions to the slow-roll parameter $\epsilon$ and its derivative $\epsilon^{\prime }.$ To accommodate the recent (large) values of $r$…

宇宙学与河外天体物理 · 物理学 2014-05-26 Gabriel German

In the slow-roll inflationary scenario, the amplitude of the curvature perturbations approaches a constant value soon after the modes leave the Hubble radius. However, relatively recently, it was shown that the amplitude of the curvature…

天体物理学 · 物理学 2008-11-26 Rajeev Kumar Jain , Pravabati Chingangbam , L. Sriramkumar

We propose a new way to implement an inflationary prior to a cosmological dataset that incorporates the inflationary observables at arbitrary order. This approach employs an exponential form for the Hubble parameter $H(\phi)$ without taking…

宇宙学与河外天体物理 · 物理学 2015-05-20 Daniel Wohns , Jiajun Xu , S. -H. Henry Tye

We investigate the inflation for the quartic hilltop model via a certain type of modified gravity. Precisely, we analyze the $F(\phi) T$ term in the Einstein's gravity to examine the quartic hilltop inflation model. $T$ is the trace of the…

广义相对论与量子宇宙学 · 物理学 2025-07-28 Feyzollah Younesizadeh , Davoud Kamani

In this paper the focus is on inflationary dynamics in the context of Einstein Gauss-Bonnet gravitational theories. We investigate the implications of the slow-roll condition on the slow-roll indices and we investigate how the inflationary…

广义相对论与量子宇宙学 · 物理学 2018-09-26 S. D. Odintsov , V. K. Oikonomou

We propose a novel inflationary scenario in string theory in which the inflaton field is a 'Wilson line' degree of freedom in the worldvolume of a probe Dp-brane, in a warped flux compactification. Kinetic terms for Wilson line fields on…

高能物理 - 理论 · 物理学 2009-02-09 A. Avgoustidis , I. Zavala

Inflation is often described through the dynamics of a scalar field, slow-rolling in a suitable potential. Ultimately, this inflaton must be identified as the expectation value of a quantum field, evolving in a quantum effective potential.…

高能物理 - 唯象学 · 物理学 2021-05-11 Jens O. Andersen , Magdalena Eriksson , Anders Tranberg

We investigate the accuracy of the slow-roll approximation for calculating perturbation spectra generated during inflation. The Hamilton-Jacobi formalism is used to evolve inflationary models with different histories. Models are identified…

天体物理学 · 物理学 2010-10-27 Sirichai Chongchitnan , George Efstathiou