Clustering Fossils from the Early Universe
Abstract
Many inflationary theories introduce new scalar, vector, or tensor degrees of freedom that may then affect the generation of primordial density perturbations. Here we show how to search a galaxy (or 21cm) survey for the imprint of primordial scalar, vector, and tensor fields. These new fields induce local departures to an otherwise statistically isotropic twopoint correlation function, or equivalently, nontrivial fourpoint correlation functions (or trispectra, in Fourier space), that can be decomposed into scalar, vector, and tensor components. We write down the optimal estimators for these various components and show how the sensitivity to these modes depends on the galaxysurvey parameters. New probes of parityviolating earlyUniverse physics are also presented.
 Publication:

Physical Review Letters
 Pub Date:
 June 2012
 DOI:
 10.1103/PhysRevLett.108.251301
 arXiv:
 arXiv:1203.0302
 Bibcode:
 2012PhRvL.108y1301J
 Keywords:

 98.80.Es;
 95.80.+p;
 98.65.Cw;
 Observational cosmology;
 Astronomical catalogs atlases sky surveys databases retrieval systems archives etc.;
 Galaxy clusters;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 High Energy Physics  Phenomenology;
 High Energy Physics  Theory
 EPrint:
 4 pages, 2 figures, submitted to PRL