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Related papers: Warm Inflation Beyond the Markovian Limit

200 papers

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 show that deviations of the quantum state of the inflaton from the thermal vacuum of inflation may leave an imprint in the CMB anisotropies. The quantum dynamics of the inflaton in such a state produces corrections to the inflationary…

High Energy Physics - Theory · Physics 2009-11-10 Nemanja Kaloper , Manoj Kaplinghat

The effect of the length of inflation on the power spectra of scalar and tensor perturbations is estimated using the power-law inflation model with a scale factor of a(t) = t^q. Considering various pre-inflation models with…

Astrophysics · Physics 2007-05-23 Shiro Hirai , Tomoyuki Takami

The study of reheating in inflationary models is crucial for understanding the early universe and gaining insights into inflationary dynamics and parameters. The reheating temperature $T_{re}$ and the duration of the reheating phase,…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-02 Gabriel German , Juan Carlos Hidalgo , Luis E. Padilla

We calculate the bispectrum of the gravitational field fluctuations generated during warm inflation, where dissipation of the vacuum potential during inflation is the mechanism for structure formation. The bispectrum is non--zero because of…

Astrophysics · Physics 2011-05-10 S. Gupta , A. Berera , A. F. Heavens , S. Matarrese

We consider a quantum deformation of the wave equation on a cosmological background as a toy-model for possible trans-Planckian effects. We compute the power spectrum of scalar and tensor fluctuations for power-law inflation, and find a…

High Energy Physics - Theory · Physics 2009-11-10 Sera Cremonini

Using the techniques of out-of-equilibrium field theory, we study the influence on the properties of cosmological perturbations generated during inflation on observable scales coming from fluctuations corresponding today to scales much…

High Energy Physics - Theory · Physics 2009-11-10 Sabino Matarrese , Marcello A. Musso , Antonio Riotto

The possibility that the scale-invariant inflationary spectrum may be modified due to the hidden assumptions about the Planck scale physics -- dubbed as trans-Planckian inflation -- has received considerable attention. To mimic the possible…

High Energy Physics - Theory · Physics 2009-11-11 S. Shankaranarayanan , Musongela Lubo

We discuss dissipative stochastic wave and diffusion equations resulting from an interaction of the inflaton with an environment in an external expanding metric. We show that a diffusion equation well approximates the wave equation in a…

General Relativity and Quantum Cosmology · Physics 2020-06-25 Z. Haba

We investigate the cosmological perturbation theory and calculate the perturbation spectra in the warm $k$-inflation. Unlike the scalar perturbations of $k$-inflation in the cold inflationary scenario, entropy perturbations should be…

General Relativity and Quantum Cosmology · Physics 2018-04-18 Zhi-Peng Peng , Jia-Ning Yu , Xiao-Min Zhang , Jian-Yang Zhu

Since trans-Planckian considerations can be associated with the re-definition of the initial vacuum, we investigate further the influence of trans-Planckian physics on the spectra produced by the initial quasi-de Sitter (dS) state during…

General Relativity and Quantum Cosmology · Physics 2018-04-06 M. Mohsenzadeh , E. Yusofi

In this paper, we undertake a detailed study of real scalar inflation by employing LATTICEEASY simulations to investigate preheating phenomena. Generally, the scalar inflation potential with non-minimal coupling can be approximated by a…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-15 Wei Cheng , Tong Qin , Jiujiang Jiang , Ruiyu Zhou

We revisit the cosmological history in the presence of light moduli by including possible thermal effects in the scalar potential. The well known cosmological moduli problem regards initial energy stored in the moduli due to a misalignment…

High Energy Physics - Theory · Physics 2021-04-28 Diego Gallego

In previous work we argued that the correct procedure to predict the gravitational wave signal from preheating after inflation rests on the in-in formalism. We extend here our previous analysis to include the backreaction of the produced…

General Relativity and Quantum Cosmology · Physics 2020-11-26 C. Armendariz-Picon

Warm inflation includes inflaton interactions with other fields throughout the inflationary epoch instead of confining such interactions to a distinct reheating era. Previous investigations have shown that, when certain constraints on the…

High Energy Physics - Phenomenology · Physics 2016-01-06 Mar Bastero-Gil , Arjun Berera , Nico Kronberg

In this paper, inflationary cosmology is reviewed, paying particular attention to its observational signatures associated with large-scale density perturbations generated from quantum fluctuations. In the most general scalar-tensor theories…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-13 Shinji Tsujikawa

String/M theory inspires an uncertainty relation between space and time which deviates from general relativity. It is possible to explore this deviation from cosmological observations, in particular from the CMB fluctuation spectrum. This…

Astrophysics · Physics 2008-11-26 Qing-Guo Huang , Miao Li

We calculate the rate of heating through phonon excitation implied by the noise postulated in mass-proportional-coupled collapse models, for a general noise power spectrum. For white noise with reduction rate $\lambda$, the phonon heating…

Quantum Physics · Physics 2018-05-23 Stephen L. Adler

There has been much recent discussion, and some confusion, regarding the use of existing observational data to estimate the likelihood that next-generation cosmic microwave background (CMB) polarization experiments might detect a nonzero…

Astrophysics · Physics 2024-03-13 Wessel Valkenburg , Lawrence M. Krauss , Jan Hamann

Conditions are obtained for the existence of a warm inflationary attractor in the system of equations describing an inflaton coupled to radiation. These conditions restrict the temperature dependence of the dissipative terms and the size of…

Astrophysics · Physics 2011-07-13 Ian G Moss , Chun Xiong