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Related papers: Warming up for Planck

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Thermal inflation is a second epoch of exponential expansion at typical energy scales $V^{1/4} \sim 10^{6 \sim 8} \mathrm{GeV}$. If the usual primordial inflation is followed by thermal inflation, the primordial power spectrum is only…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-09 Kihyun Cho , Sungwook E. Hong , Ewan D. Stewart , Heeseung Zoe

We investigate the relevance of quantum gravity during inflation to address the Hubble tension that arises from Planck 2018 and SH0ES data sets. We show that the effect of quantum gravity during inflation can increase the rate of change of…

General Relativity and Quantum Cosmology · Physics 2024-02-06 Anupama B , P K Suresh

We investigate the impact of different choice of prior's range for the reheating epoch on cosmic inflation parameter inference in light of cosmic microwave background (CMB) anisotropy measurements from the {\em Planck} 2018 legacy release…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-30 Mario Ballardini

Is there new physics hidden in the four-point function of the cosmic microwave background (CMB)? We conduct a detailed analysis of the Planck PR4 temperature and polarization trispectrum for $\ell\in[2,2048]$. Using the theoretical and…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-30 Oliver H. E. Philcox

We survey recent calculations probing what constraints decoupling can put on the influence of very-high-energy physics on the predictions of inflation for the cosmic microwave background. Using garden-variety hybrid inflation models we…

Astrophysics · Physics 2007-05-23 C. P. Burgess , J. Cline , F. Lemieux , R. Holman

We are in the era of precision cosmology which offers us a unique opportunity to investigate beyond standard model physics. Toward this endeavor, inflaton is assumed to be a perfect new physics candidate. In this submission, we explore the…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-20 Ayan Chakraborty , Md Riajul Haque , Debaprasad Maity , Rajesh Mondal

We study temperature and polarization anisotropies of the cosmic microwave background (CMB) radiation sourced from primordial cross-bispectra between metric perturbations and vector fields, which are generated from the inflation model where…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-18 Maresuke Shiraishi , Shohei Saga , Shuichiro Yokoyama

I will discuss to what degree the cosmic microwave background (CMB) can be used to constrain primordial non-Gaussianity involving one tensor and two scalar fluctuations, focusing on the correlation of one $B$-mode polarization fluctuation…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-18 P. Daniel Meerburg

Recent released WMAP data show a low value of quadrupole in the CMB temperature fluctuations, which confirms the early observations by COBE. In this paper we consider a model of two inflatons with different masses, $V(\phi_1,\phi_2)={1\over…

Astrophysics · Physics 2009-11-07 Bo Feng , Xinmin Zhang

The 2015 Planck data release tightened the region of the allowed inflationary models. Inflationary models with convex potentials have now been ruled out since they produce a large tensor to scalar ratio. Meanwhile the same data offers…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Eleonora Di Valentino , Laura Mersini-Houghton

We study inflationary scenarios driven by a scalar field in the presence of a non-minimal coupling between matter and curvature. We show that the Friedmann equation can be significantly modified when the energy density during inflation…

General Relativity and Quantum Cosmology · Physics 2017-06-28 Cláudio Gomes , João G. Rosa , Orfeu Bertolami

We investigate the production of a spectator scalar dark matter field that is directly coupled to the inflaton during inflation and reheating. We consider two specific inflationary potentials, namely the Starobinsky and T-model of…

High Energy Physics - Phenomenology · Physics 2023-06-16 Marcos A. G. Garcia , Mathias Pierre , Sarunas Verner

In the standard inflationary scenario, primordial perturbations are adiabatic. The amplitudes of most types of isocurvature perturbations are generally constrained by current data to be small. If, however, there is a baryon-density…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-24 Julian B. Muñoz , Daniel Grin , Liang Dai , Marc Kamionkowski , Ely D. Kovetz

We investigate whether a recently proposed modulation of the power spectrum of primordial density fluctuations generated through transplankian (maybe stringy) effects during inflation can be observed. We briefly review the mechanism leading…

High Energy Physics - Theory · Physics 2014-11-18 L. Bergstrom , U. H. Danielsson

Thermal fluctuations provide the main source of large scale density perturbations in warm inflationary models of the early universe. For the first time, general results are obtained for the power spectrum in the case when the friction…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-28 Chris Graham , Ian G Moss

We compute the power spectrum of super-horizon curvature perturbations generated during a late period of thermal inflation, taking into account fluctuation-dissipation effects resulting from the scalar flaton field's interactions with the…

High Energy Physics - Phenomenology · Physics 2024-07-22 Mar Bastero-Gil , Joaquim M. Gomes , João G. Rosa

We study the power spectrum of the mass density perturbations in an inflation scenario that includes thermal dissipation. We show that the condition on which the thermal fluctuations dominate the primordial density perturbations can easily…

Astrophysics · Physics 2009-10-31 Wolung Lee , Li-Zhi Fang

We revisit the idea that the inflaton may have dissipated part of its energy into a thermal bath during inflation, considering monomial inflationary potentials and three different forms of dissipation rate. Using a numerical Fokker-Planck…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-06 Guillermo Ballesteros , Alejandro Pérez Rodríguez , Mathias Pierre

An inflationary model in the framework of noncommutative space-time may generate a nontrivial running of the scalar spectral index, but usually induces a large tensor-to-scalar ratio simultaneously. With the latest observational data from…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-11 Nan Li , Xin Zhang

We demonstrate that "natural inflation", also known as "axion inflation", can be compatible with Planck 2018 measurements of the cosmic microwave background, while predicting an exponentially small tensor-to-scalar ratio, e.g., $r\sim…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-16 Dario L. Lorenzoni , David I. Kaiser , Evan McDonough
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