Nonlocal bispectra from super cosmic variance

Bekir Baytaş, Aruna Kesavan, Elliot Nelson, Sohyun Park, Sarah Shandera

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

We present examples of non-Gaussian statistics that can induce bispectra matching local and nonlocal (including equilateral) templates in biased subvolumes. We find cases where the biasing from coupling to long wavelength modes affects only the power spectrum, only the bispectrum or both. Our results suggest that ruling out multifield scenarios is quite difficult: some measurements of the scalar correlations, including the shape of the bispectrum, can be consistent with single-clock predictions even when cosmic variance from super-horizon modes is at work. Furthermore, if observations of the density perturbations rule out single-clock inflation, we will face a serious cosmic variance obstacle in drawing any further conclusions about the particle physics origin of the scalar fluctuations.

Original languageEnglish (US)
Article number083518
JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
Volume91
Issue number8
DOIs
StatePublished - Apr 9 2015

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clocks
scalars
horizon
power spectra
templates
statistics
perturbation
physics
predictions
wavelengths

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Physics and Astronomy (miscellaneous)

Cite this

Baytaş, Bekir ; Kesavan, Aruna ; Nelson, Elliot ; Park, Sohyun ; Shandera, Sarah. / Nonlocal bispectra from super cosmic variance. In: Physical Review D - Particles, Fields, Gravitation and Cosmology. 2015 ; Vol. 91, No. 8.
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Nonlocal bispectra from super cosmic variance. / Baytaş, Bekir; Kesavan, Aruna; Nelson, Elliot; Park, Sohyun; Shandera, Sarah.

In: Physical Review D - Particles, Fields, Gravitation and Cosmology, Vol. 91, No. 8, 083518, 09.04.2015.

Research output: Contribution to journalArticle

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