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Related papers: Warming up for Planck

200 papers

Eternal inflation is studied in the context of warm inflation. We focus on different tools to analyze the effects of dissipation and the presence of a thermal radiation bath on the fluctuation-dominated regime, for which the…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-14 Gustavo S. Vicente , Leandro A. da Silva , Rudnei O. Ramos

If inflation was preceded by a radiation era then at the time of inflation there will exist a decoupled thermal distribution of gravitons. Gravitational waves generated during inflation will be amplified by the process of stimulated…

Astrophysics · Physics 2008-11-26 Kaushik Bhattacharya , Subhendra Mohanty , Akhilesh Nautiyal

We investigate the impact of a hypothesized delayed initiation of inflation, characterized by a cutoff k_min to the primordial power spectrum in the cosmic microwave background (CMB). This cutoff affects both the scalar and tensor spectra,…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-28 Jingwei Liu , Fulvio Melia

If the inflationary era is preceded by a radiation dominated era in which the inflaton too was in thermal equilibrium at some very early time then the CMB data places an upper bound on the comoving temperature of the (decoupled) inflaton…

High Energy Physics - Phenomenology · Physics 2016-01-26 Suratna Das , Gaurav Goswami , Jayanti Prasad , Raghavan Rangarajan

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

The concept of early Universe inflation resolves several problems of hot Big Bang theory and quantitatively explains the origin of the inhomogeneities in the present Universe. However, it is not possible to arrange inflation in a scalar…

High Energy Physics - Phenomenology · Physics 2024-02-06 Anna Tokareva

The role of dissipation from the thermal bath of minimal warm inflation (MWI)is examined with the Cosmic Microwave Background (CMB) to assess its ability to mimic a dynamical dark energy component. An increase in the dissipation strength…

General Relativity and Quantum Cosmology · Physics 2026-03-31 Anupama B

Multifield models of inflation with nonminimal couplings are in excellent agreement with the recent results from {\it Planck}. Across a broad range of couplings and initial conditions, such models evolve along an effectively single-field…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-08 David I. Kaiser , Evangelos I. Sfakianakis

The observational status of inflation after the Planck 2013 and 2015 results and the BICEP2/Keck Array and Planck joint analysis is discussed. These pedagogical lecture notes are intended to serve as a technical guide filling the gap…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-22 Jerome Martin

We investigate theoretical and observational aspects of a warm inflation scenario driven by the $\beta$-exponential potential, which generalizes the well-known power law inflation. In such a scenario, the decay of the inflaton field into…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-02 F. B. M. dos Santos , R. Silva , S. Santos da Costa , M. Benetti , J. S. Alcaniz

A thorough MCMC analysis of any inflationary model against the current cosmological data is essential for assessing the validity of such a model as a viable inflationary model. Warm Inflation, producing both thermal and quantum…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-29 Umang Kumar , Suratna Das

In standard inflationary cosmology, scalar and tensor perturbations grew as the Universe expanded and froze when their wavelengths exceeded the Hubble horizon, producing a tell-tale signature in the fluctuation spectrum and amplitude of the…

General Relativity and Quantum Cosmology · Physics 2023-07-21 Fulvio Melia

We revisit the scenario where inflation is preceded by a radiation era by considering that the inflaton too could have been in thermal equilibrium early in the radiation era. Hence we take into account not only the effect of a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Suratna Das , Gaurav Goswami , Jayanti Prasad , Raghavan Rangarajan

Inflation creates perturbations for the large scale structures in the universe, but it also dilutes everything. Therefore it is pertinent that the end of inflation must explain how to excite the Standard Model {\it dof} along with the dark…

High Energy Physics - Phenomenology · Physics 2013-07-22 Lingfei Wang , Ernestas Pukartas , Anupam Mazumdar

We show how a radiation dominated universe subject to space-time quantization may give rise to inflation as the radiation temperature exceeds the Planck temperature. We consider dispersion relations with a maximal momentum (i.e. a mimimum…

High Energy Physics - Theory · Physics 2009-11-07 Stephon Alexander , Robert Brandenberger , Joao Magueijo

The recently released data from the $\textit{Atacama Cosmology Telescope}$ (ACT) confirms that the primordial scalar spectrum is extremely flat. This, together with current upper bounds on the tensor-to-scalar ratio, implies that the…

High Energy Physics - Theory · Physics 2025-11-24 Arjun Berera , Suddhasattwa Brahma , Zizang Qiu , Rudnei O. Ramos , Gabriel S. Rodrigues

Space-based missions studying the cosmic microwave background (CMB) have progressively refined the parameter space in conventional models of inflation shortly ($\sim 10^{-37}$ seconds) after the big bang. While most inflationary scenarios…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-18 Jingwei Liu , Fulvio Melia

Inflation creates both scalar (density) and tensor (gravity wave) metric perturbations. We find that the tensor mode contribution to the CMB anisotropy on large-angular scales can only exceed that of the scalar mode in models where the…

Astrophysics · Physics 2009-09-15 R. L. Davis , H. M. Hodges , G. F. Smoot , P. J. Steinhardt , M. S. Turner

Cosmic Microwave Background (CMB) is an important probe for understanding the inflationary era of the Universe. We consider the Perturbed Power Law (PPL) model of inflation which is a soft deviation from Power Law (PL) inflationary model.…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-03 Suvodip Mukherjee , Santanu Das , Minu Joy , Tarun Souradeep

This paper is devoted to study the warm inflation using vector fields in the background of locally rotationally symmetric Bianchi type I universe model. We formulate the field equations, slow-roll and perturbation parameters (scalar and…

General Relativity and Quantum Cosmology · Physics 2015-06-18 M. Sharif , Rabia Saleem