BICEP's acceleration
Abstract
The recent Bicep2 [1] detection of, what is claimed to be primordial Bmodes, opens up the possibility of constraining not only the energy scale of inflation but also the detailed acceleration history that occurred during inflation. In turn this can be used to determine the shape of the inflaton potential V(φ) for the first time — if a single, scalar inflaton is assumed to be driving the acceleration. We carry out a Monte Carlo exploration of inflationary trajectories given the current data. Using this method we obtain a posterior distribution of possible acceleration profiles ε(N) as a function of efold N and derived posterior distributions of the primordial power spectrum P(k) and potential V(φ). We find that the Bicep2 result, in combination with Planck measurements of total intensity Cosmic Microwave Background (CMB) anisotropies, induces a significant feature in the scalar primordial spectrum at scales k∼ 10{sup 3} Mpc {sup 1}. This is in agreement with a previous detection of a suppression in the scalar power [2].
 Authors:
 Theoretical Physics, Blackett Laboratory, Imperial College, London, SW7 2BZ (United Kingdom)
 Publication Date:
 OSTI Identifier:
 22375793
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2014; Journal Issue: 10; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCELERATION; ANISOTROPY; COSMOLOGICAL INFLATION; DETECTION; DISTRIBUTION; EXPLORATION; FUNCTIONS; MONTE CARLO METHOD; POTENTIALS; RELICT RADIATION; SCALARS; SPECTRA
Citation Formats
Contaldi, Carlo R., Email: c.contaldi@imperial.ac.uk. BICEP's acceleration. United States: N. p., 2014.
Web. doi:10.1088/14757516/2014/10/072.
Contaldi, Carlo R., Email: c.contaldi@imperial.ac.uk. BICEP's acceleration. United States. doi:10.1088/14757516/2014/10/072.
Contaldi, Carlo R., Email: c.contaldi@imperial.ac.uk. 2014.
"BICEP's acceleration". United States.
doi:10.1088/14757516/2014/10/072.
@article{osti_22375793,
title = {BICEP's acceleration},
author = {Contaldi, Carlo R., Email: c.contaldi@imperial.ac.uk},
abstractNote = {The recent Bicep2 [1] detection of, what is claimed to be primordial Bmodes, opens up the possibility of constraining not only the energy scale of inflation but also the detailed acceleration history that occurred during inflation. In turn this can be used to determine the shape of the inflaton potential V(φ) for the first time — if a single, scalar inflaton is assumed to be driving the acceleration. We carry out a Monte Carlo exploration of inflationary trajectories given the current data. Using this method we obtain a posterior distribution of possible acceleration profiles ε(N) as a function of efold N and derived posterior distributions of the primordial power spectrum P(k) and potential V(φ). We find that the Bicep2 result, in combination with Planck measurements of total intensity Cosmic Microwave Background (CMB) anisotropies, induces a significant feature in the scalar primordial spectrum at scales k∼ 10{sup 3} Mpc {sup 1}. This is in agreement with a previous detection of a suppression in the scalar power [2].},
doi = {10.1088/14757516/2014/10/072},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 10,
volume = 2014,
place = {United States},
year = 2014,
month =
}

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