English
Related papers

Related papers: Limits on primordial power spectrum resolution: An…

200 papers

Inflation may provide unique insight into the physics at the highest available energy scales that cannot be replicated in any realistic terrestrial experiment. Features in the primordial power spectrum are generically predicted in a wide…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-26 Anže Slosar , Xingang Chen , Cora Dvorkin , Daniel Green , P. Daniel Meerburg , Eva Silverstein , Benjamin Wallisch

We investigate the generation of features at large scales in the primordial power spectrum (PPS) when inflation is driven by two scalar fields. In canonical single field models of inflation, these features are often generated due to…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-19 Matteo Braglia , Dhiraj Kumar Hazra , L. Sriramkumar , Fabio Finelli

In the ``natural inflation'' model, the inflaton potential is periodic. We show that Planck scale physics may induce corrections to the inflaton potential, which is also periodic with a greater frequency. Such high frequency corrections…

Astrophysics · Physics 2008-11-26 Xiulian Wang , Bo Feng , Mingzhe Li , Xue-Lei Chen , Xinmin Zhang

The computation of the primordial power spectrum in multi-field inflation models requires us to correctly account for all relevant interactions between adiabatic and non-adiabatic modes around and after horizon crossing. One specific…

High Energy Physics - Phenomenology · Physics 2015-03-17 Ana Achúcarro , Jinn-Ouk Gong , Sjoerd Hardeman , Gonzalo A. Palma , Subodh P. Patil

We present estimates of parameters which model the primordial density fluctuations using CMB data from the VSA, 1st year WMAP, CBI and ACBAR along with external priors from 2dF and the HST. Taken at face value there is significant evidence…

Astrophysics · Physics 2007-05-23 Richard A. Battye , the VSA Collaboration

Recently, the Planck 2013 results showed possible evidence for a dipolar power modulation of the CMB temperature fluctuations at low--(\ell) multipoles. This anomaly might imply certain deviations from statistical isotropy. To incorporate…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-24 Zhe Chang , Sai Wang

We describe models of single-field inflation with small and sharp step features in the potential (and sound speed) of the inflaton field, in the context of the Effective Field Theory of Inflation. This approach allows us to study the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Nicola Bartolo , Dario Cannone , Sabino Matarrese

We discuss the issue of how precisely we can measure the primordial power spectrum by using future observations of 21 cm fluctuations and cosmic microwave background (CMB). For this purpose, we investigate projected constraints on the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Kazunori Kohri , Yoshihiko Oyama , Toyokazu Sekiguchi , Tomo Takahashi

Recent Planck data show the anomalies of CMB fluctuations on large angular scales, which confirms the early observations by WMAP. We continue studying an inflationary model, in which before the slow roll inflation the universe is in a…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-15 Zhi-Guo Liu , Zong-Kuan Guo , Yun-Song Piao

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

We use Minkowski Functionals to explore the presence of non-Gaussian signatures in simulated cosmic microwave background (CMB) maps. Precisely, we analyse the non-Gaussianities produced from the angular power spectra emerging from a class…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-08 Camila P. Novaes , Micol Benetti , Armando Bernui

Although the cosmic microwave background (CMB) is largely understood to be homogeneous and isotropic, the CMB angular power spectra present anomalies that seem to break down parity symmetry at large angular scales. We argue that the…

General Relativity and Quantum Cosmology · Physics 2024-11-12 K. Sravan Kumar , João Marto

The ability to test and constrain theories of cosmic inflation will advance substantially over the next decade. Key data sources include cosmic microwave background (CMB) measurements and observations of the distribution of matter at…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-13 Benedict Bahr-Kalus , David Parkinson , Richard Easther

We make a comprehensive investigation of the observational effect of the inflation consistency relation. We focus on the general single-field inflation model with the consistency relation $r=-8c_s n_t$, and investigate the observational…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Cheng Cheng , Qing-Guo Huang , Xiao-Dong Li , Yin-Zhe Ma

The simplest models of inflation predict small non-gaussianities and a featureless power spectrum. However, there exist a large number of well-motivated theoretical scenarios in which large non-gaussianties could be generated. In general,…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-11 Stefano Gariazzo , Laura Lopez-Honorez , Olga Mena

Future astrophysical datasets promise to strengthen constraints on models of inflation, and extracting these constraints requires methods and tools commensurate with the quality of the data. In this paper we describe ModeCode, a new,…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-10 Michael J. Mortonson , Hiranya V. Peiris , Richard Easther

Cosmological $\alpha$-attractors stand out as particularly compelling models to describe inflation in the very early universe, naturally meeting tight observational bounds from cosmic microwave background (CMB) experiments. We investigate…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-22 Laura Iacconi , Hooshyar Assadullahi , Matteo Fasiello , David Wands

The CMB power spectra are studied for different families of single field new and chaotic inflation models in the effective field theory approach to inflation. We implement a systematic expansion in 1/N_e where N_e ~ 50 is the number of…

Astrophysics · Physics 2008-11-26 D. Boyanovsky , H. J. de Vega , C. M. Ho , N. G. Sanchez

We revisit an inflationary scenario in which primordial inhomogeneities arise from a quantum collapse, a stochastic mechanism described in the context of quantum collapse theories in its continuous version and within semiclassical gravity.…

General Relativity and Quantum Cosmology · Physics 2026-03-04 María Pía Piccirilli , Gabriel León , Rosa-Laura Lechuga-Solis , Daniel Sudarsky

We obtain cosmological constraints on models of inflation which exhibit rapid roll solutions. Rapid roll attractors exist for potentials with large mass terms and are thus of interest for inflationary model building within string theory. We…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-15 Takeshi Kobayashi , Shinji Mukohyama , Brian A. Powell