English
Related papers

Related papers: CMB Scale Dependent Non-Gaussianity from Massive G…

200 papers

The inflationary paradigm is extremely successful regarding predictions of temperature anisotropies in the CMB. However, inflation also makes predictions for a CMB B-mode polarization, which has not been detected. Moreover, the standard…

General Relativity and Quantum Cosmology · Physics 2018-07-24 Gabriel León , Abhishek Majhi , Elias Okon , Daniel Sudarsky

We study a model of inflation where the scalar perturbations are almost gaussian while there is sizable (equilateral) nongaussianity in the tensor sector. In this model, a rolling pseudoscalar gravitationally coupled to the inflaton…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-28 Jessica L. Cook , Lorenzo Sorbo

We show that in theories with a nontrivial kinetic term the contribution of the gravitational waves to the CMB fluctuations can be substantially larger than that is naively expected in simple inflationary models. This increase of the…

Astrophysics · Physics 2014-10-13 V. Mukhanov , A. Vikman

We investigate parity-violating signatures of temperature and polarization bispectra of the cosmic microwave background (CMB) in an inflationary model where a rolling pseudoscalar produces large equilateral tensor non-Gaussianity. By a…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-22 Maresuke Shiraishi , Angelo Ricciardone , Shohei Saga

It is well known that in manifestly Lorentz invariant theories with nontrivial kinetic terms, perturbations around some classical backgrounds can travel faster than light. These exotic "supersonic" models may have interesting consequences…

Astrophysics · Physics 2009-09-29 Alexander Vikman

A B-mode polarization signal in the cosmic microwave background (CMB) is widely regarded as smoking gun evidence for gravitational waves produced during inflation. Here, we demonstrate that tensor perturbations sourced during…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-22 Kylar Greene , Aurora Ireland , Gordan Krnjaic , Yuhsin Tsai

Upcoming cosmic microwave background (CMB) data can be used to explore harmonic 3-point functions that involve the B-mode component of the CMB polarization signal. We focus on bispectra describing the non-Gaussian correlation of the B-mode…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-15 Adriaan J. Duivenvoorden , P. Daniel Meerburg , Katherine Freese

It is plausible that the scalar density perturbations are created by a relatively low scale model of inflation which predicts the CMB anisotropy and excites Standard Model baryon and cold dark matter, but negligible gravity waves.…

Astrophysics · Physics 2008-04-03 Rouzbeh Allahverdi , Anupam Mazumdar , Tuomas Multamaki

A detection of excess cosmic microwave background (CMB) B-mode polarization on large scales allows the possibility of measuring not only the amplitude of these fluctuations but also their scale dependence, which can be parametrized as the…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-06 Gabrielle Simard , Duncan Hanson , Gil Holder

We introduce the real space correlation function of $B$-mode polarization of the cosmic microwave background (CMB) as a probe of superhorizon tensor perturbations created by inflation. By causality, any non-inflationary mechanism for…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-15 Daniel Baumann , Matias Zaldarriaga

Observations of the polarization of the cosmic microwave backround (CMB) have the potential to place much tighter constraints on cosmological parameters than observations of the fluctuations in temperature alone. We discuss using CMB…

Astrophysics · Physics 2009-10-30 William H. Kinney

The temperature perturbations of the cosmic microwave background radiation (CMB) appear systematically suppressed, at large angular scales, with respect to the prediction of the LambdaCDM concordance model. This behavior might be a glimpse…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-14 Noriaki Kitazawa

We study non-Gaussian signatures on the cosmic microwave background (CMB) radiation predicted within inflationary models with non-vacuum initial states for cosmological perturbations. The model incorporates a privileged scale, which implies…

Astrophysics · Physics 2008-11-26 Alejandro Gangui , Jerome Martin , Mairi Sakellariadou

The temperature and polarization anisotropies of the Cosmic Microwave Background are analyzed under the hypothesis that the same inflationary seed accounting for protogalactic magnetism also affects the Einstein-Boltzmann hierarchy whose…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-02 Massimo Giovannini

We probe the cosmological consequences of a recently proposed class of solutions to the cosmological constant problem. In these models, the universe undergoes a long period of inflation followed by a contraction and a bounce that sets the…

High Energy Physics - Phenomenology · Physics 2022-01-27 Lingyuan Ji , David E. Kaplan , Surjeet Rajendran , Erwin H. Tanin

We investigate the possibility that a heavy scalar field, whose mass exceeds the Hubble scale during inflation, could leave non-negligible signatures in the Cosmic Microwave Background (CMB) temperature anisotropy power spectrum through the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Ryo Saito , Masahiro Nakashima , Yu-ichi Takamizu , Jun'ichi Yokoyama

We present an all-sky formalism for the Cosmic Microwave Background (CMB) bispectrum induced by the primordial non-Gaussianities not only in scalar but also in vector and tensor fluctuations. We find that the bispectrum can be formed in an…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Maresuke Shiraishi , Daisuke Nitta , Shuichiro Yokoyama , Kiyotomo Ichiki , Keitaro Takahashi

Gravitational waves from inflation induce polarization patterns in the cosmic microwave background (CMB). It is known that there are only two types of non-Gaussianities of the gravitaional waves in the most general scalar field theories…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-01 Hiroaki W. H. Tahara , Jun'ichi Yokoyama

Recent measurements of temperature fluctuations in the cosmic microwave background (CMB) indicate that the Universe is flat and that large-scale structure grew via gravitational infall from primordial adiabatic perturbations. Both of these…

Astrophysics · Physics 2009-10-31 Marc Kamionkowski , Andrew H. Jaffe

In this work, we investigate the physical aspects of the inflection-point inflation scenario and assess its observational viability in light of current Cosmic Microwave Background (CMB) data. The model we consider encapsulates the inflaton…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-25 Jamerson G. Rodrigues , Vinícius Oliveira , Rodrigo von Marttens , Carlos A. de S. Pires , Jailson Alcaniz