Observing the temperature of the Big Bang through large scale structure
(2007)
Observing the temperature of the Big Bang through large scale structure
ArXiv 0708.0429 (2007)
Abstract:
It is widely accepted that the Universe underwent a period of thermal equilibrium at very early times. One expects a residue of this primordial state to be imprinted on the large scale structure of space time. In this paper we study the morphology of this thermal residue in a universe whose early dynamics is governed by a scalar field. We calculate the amplitude of fluctuations on large scales and compare it to the imprint of vacuum fluctuations. We then use the observed power spectrum of fluctuations on the cosmic microwave background to place a constraint on the temperature of the Universe before and during inflation. We also present an alternative scenario where the fluctuations are predominantly thermal and near scale-invariant.Generalized Einstein-Aether theories and the Solar System
ArXiv 0707.3519 (2007)
Abstract:
It has been shown that generalized Einstein-Aether theories may lead to significant modifications to the non-relativistic limit of the Einstein equations. In this paper we study the effect of a general class of such theories on the Solar System. We consider corrections to the gravitational potential in negative and positive powers of distance from the source. Using measurements of the perihelion shift of Mercury and time delay of radar signals to Cassini, we place constraints on these corrections. We find that a subclass of generalized Einstein-Aether theories are compatible with these constraints.Searching for non Gaussian signals in the BOOMERanG 2003 CMB maps
ArXiv 0705.1615 (2007)