2k citations · 34.3k across the 249 of their papers we have counts for
12 papers · 1 filter
Probing Primordial Non-Gaussianity with Large-Scale Structure
Roman Scoccimarro, Emiliano Sefusatti, Matias Zaldarriaga
We consider primordial non-Gaussianity due to quadratic corrections in the gravitational potential parametrized by a non-linear coupling parameter fnl. We study constraints on fnl…
CMBfit: Rapid WMAP likelihood calculations with normal parameters
Havard B. Sandvik, Max Tegmark, Xiaomin Wang +1
We present a method for ultra-fast confrontation of the WMAP cosmic microwave background observations with theoretical models, implemented as a publicly available software package…
Ghost Inflation
Nima Arkani-Hamed, Paolo Creminelli, Shinji Mukohyama +1
We propose a new scenario for early cosmology, where an inflationary de Sitter phase is obtained with a ghost condensate. The transition to radiation dominance is triggered by the…
Measuring the Small-Scale Power Spectrum of Cosmic Density Fluctuations Through 21 cm Tomography Prior to the Epoch of Structure Formation
Abraham Loeb, Matias Zaldarriaga
The thermal evolution of the cosmic gas decoupled from that of the cosmic microwave background (CMB) at a redshift z~200. Afterwards and before the first stars had formed, the cosm…
21 Centimeter Fluctuations from Cosmic Gas at High Redshifts
Matias Zaldarriaga, Steven Furlanetto, Lars Hernquist
The relatively large Thomson optical depth, tau_e, inferred recently from the WMAP observations suggests that the Universe was reionized in a more complex manner than previously be…
Towards Constraints on Dark Energy from Absorption Spectra of Close Quasar Pairs
Adam Lidz, Lam Hui, Arlin P. S. Crotts +1
A comparison between the line of sight power spectrum of absorption in the Lyman-alpha forest and the cross power spectrum between the absorption in neighboring lines of sight offe…
The significance of the largest scale CMB fluctuations in WMAP
Angelica de Oliveira-Costa, Max Tegmark, Matias Zaldarriaga +1
We investigate anomalies reported in the Cosmic Microwave Background maps from the Wilkinson Microwave Anisotropy Probe (WMAP) satellite on very large angular scales and discuss po…
A comparison of cosmological Boltzmann codes: are we ready for high precision cosmology?
U. Seljak, N. Sugiyama, M. White +1
We compare three independent, cosmological linear perturbation theory codes to asses the level of agreement between them and to improve upon it by investigating the sources of disc…
Non-Gaussianities in models with a varying inflaton decay rate
Matias Zaldarriaga
We consider the expected level of primordial non-Gaussianities in models in which density perturbations are produced by spatial fluctuations in the decay rate of the inflaton. We c…
Cosmological Perturbations From Inhomogeneous Reheating, Freeze-Out, and Mass Domination
Gia Dvali, Andrei Gruzinov, Matias Zaldarriaga
We generalize a recently proposed mechanism for the origin of primordial metric perturbations in inflationary models. Quantum fluctuations of light scalar fields during inflation g…
The Polarization of the Cosmic Microwave Background
Matias Zaldarriaga
We summarize the physical mechanism by which the Cosmic Microwave Background acquires a small degree of polarization. We discuss the imprint left by gravitational waves and the use…
A new mechanism for generating density perturbations from inflation
Gia Dvali, Andrei Gruzinov, Matias Zaldarriaga
We propose a new mechanism to generate density perturbations in inflationary models. Spatial fluctuations in the decay rate of the inflaton field to ordinary matter lead to fluctua…