Testing Inflation with Large Scale Structure: Connecting Hopes with Reality

Marcelo Alvarez; Tobias Baldauf; J. Richard Bond; Neal Dalal; Roland de Putter; Olivier Doré; Daniel Green; Chris Hirata; Zhiqi Huang; Dragan Huterer; Donghui Jeong; Matthew C. Johnson; Elisabeth Krause; Marilena Loverde; Joel Meyers; P. Daniel Meerburg; Leonardo Senatore; Sarah Shandera; Eva Silverstein; Anže Slosar; Kendrick Smith; Matias Zaldarriaga; Valentin Assassi; Jonathan Braden; Amir Hajian; Takeshi Kobayashi; George Stein; Alexander van Engelen

arXiv · 1412.4671

Testing Inflation with Large Scale Structure: Connecting Hopes with Reality

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Abstract

The statistics of primordial curvature fluctuations are our window into the period of inflation, where these fluctuations were generated. To date, the cosmic microwave background has been the dominant source of information about these perturbations. Large scale structure is however from where drastic improvements should originate. In this paper, we explain the theoretical motivations for pursuing such measurements and the challenges that lie ahead. In particular, we discuss and identify theoretical targets regarding the measurement of primordial non-Gaussianity. We argue that when quantified in terms of the local (equilateral) template amplitude $f_{\rm NL}^{\rm loc}$ ($f_{\rm NL}^{\rm eq}$), natural target levels of sensitivity are $Δf_{\rm NL}^{\rm loc, eq.} \simeq 1$. We highlight that such levels are within reach of future surveys by measuring 2-, 3- and 4-point statistics of the galaxy spatial distribution. This paper summarizes a workshop held at CITA (University of Toronto) on October 23-24, 2014.

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Marcelo Alvarez, Tobias Baldauf, J. Richard Bond, Neal Dalal, Roland de Putter, Olivier Doré, Daniel Green, Chris Hirata, Zhiqi Huang, Dragan Huterer, Donghui Jeong, Matthew C. Johnson, Elisabeth Krause, Marilena Loverde, Joel Meyers, P. Daniel Meerburg, Leonardo Senatore, Sarah Shandera, Eva Silverstein, Anže Slosar, Kendrick Smith, Matias Zaldarriaga, Valentin Assassi, Jonathan Braden, Amir Hajian, Takeshi Kobayashi, George Stein, Alexander van Engelen. 2014-12-15. Testing Inflation with Large Scale Structure: Connecting Hopes with Reality. https://arxiv.org/abs/1412.4671

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