Bollettino Settimanale Lunedì 31 marzo 2014 AULA CONVERSI ore 16.00 SEMINARIO TEORICO INFN Martedi’ 1 aprile 2014 AULA AMALDI ore 16.00 SEMINARIO GENERALE Effective string models for Lattice Detection of B-mode Polarization in the Cosmic Gauge Theories Microwave Background Radiation at Degree Angular Scales with BICEP2 Michele Caselle (Università di Torino) Angiola Orlando (Dep. of Physics, Univ. of California The interquark potential of whatever confining at San Diego) gauge theory in D space-time dimensions can be described, at large quark separation, by an effective string theory. Recently two important advances improved our understanding of this effective theory. First, it was realized that the form of the effective action is strongly constrained by the requirement of the Lorentz invariance of the gauge theory, which is spontaneously broken by the formation of a long confining flux tube in the vacuum. This constraint is strong enough to fix uniquely the first few subleading terms of the action which turn out to coincide with those of the NambuGoto string theory. Second, it was understood how to obtain the exact Nambu-Goto spectrum by a suitable integrable perturbation of the 2d c=1 Conformal Field Theory. In this talk we first review the general implications of these two results for Lattice Gauge Theories and then, as a test of the power of these methods, use them to construct the first few boundary corrections to the effective string action. Finally, as a side application of effective string models, we discuss a new approach to the evaluation of glueball masses in finite temperature Lattice Gauge Theories. The BICEP2 telescope is an instrument designed to search for the signature of primordial gravitational waves on the polarization of the cosmic microwave background (CMB) at degree angular scales. Such gravitational waves are a generic prediction of inflationary models of the early universe. BICEP2 observed from the South Pole for three seasons from 2010 to 2012, mapping the sky at 150GHz with a planar array of 500 polarization sensitive antenna-coupled TES bolometers. This new detector technology has enabled a large increase in sensitivity with respect to previous instruments. I will present the first results from this instrument, outline the observations and the analysis that led to this result, and discuss its implications for cosmology. AULA AMALDI ore 17.00 SEMINARIO DI ASTROFISICA The impact of the Bicep2 result on cosmology Alessandro Melchiorri (dip. Fisica, Sapienza) I will discuss some of the implications of the recent results from the bicep2 experiment for cosmology and fundamental physics.In particular I will focus on inflationary models, neutrino physics and modified gravity scenarios. I will show that the apparent tension on the amplitude of tensor modes between bicep2 and planck experiments could be solved by considering new physics as extra sterile neutrinos. Mercoledi’ 2 aprile 2014 Giovedi’ 3 aprile 2014 Venerdì 4 aprile 2014
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