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Review Talks REVIEW TALKS ALDO MORSELLI II UNIVERSITA DI ROMA "TOR VERGATA” - ITALY ARIEL SÁNCHEZ MPE - GERMANY CARLA BONIFAZI UFRJ - BRAZIL CHRISTOPHER J. CONSELICE UNIVERSITY OF NOTTINGHAM - UNITED KINGDOM JODI COOLEY SOUTHERN METHODIST UNIV. - USA KEN GANGA APC - FRANCE “THE PLANCK MISSION” The planck satellite, created to measure the anisotropies in the temperature and polarization of the cosmic microwave background, was launched in may of 2009 and has performed well. Some early, non-cmb results have been published already. The first set of cmb temperature data and papers will be released at the beginning of 2013. The full data set, including polarization, is scheduled to be made public in early 2014. Galactic and other astronomical results will continue to be released during this period. I will review the non-cmb results which have been released to date and give previews of what we hope to be able to do with the cosmological data releases. MATTHIAS STEINMETZ AIP - GERMANY NICOLAO FORNENGO UNIVERSITY OF TORINI - ITALY PAOLO SALUCCI SISSA – ITALY “DARK MATTER IN GALAXIES: LEADS TO ITS NATURE” In the past years a wealth of observations has revealed the structural properties of the Dark and Luminous mass distribution in galaxies. These have pointed out to an intriguing scenario. In spirals, the investigation of individual and coadded objects has shown that their rotation curves follow, from their centers out to their virial radii, a Universal profile (URC) that arises from a tuned combination of a stellar disk and of a dark halo. The importance of the latter component decreases with galaxy mass. Individual objects have clearly revealed that the dark halos encompassing the luminous discs have a constant density core. Significantly galaxies of other and very differeny Hubble types show similar properties in the dark component. This scenario poses seriuos challenges to "raw" ΛCDM Cosmology implying that in scenario baryions lead the formation of galaxies. On the other hand, this phenomenology may indicate, for the dark particle, a different nature . THOMAS SOTIRIOU SISSA - ITALY YUN WANG THE UNIV. OF OKLAHOMA - USA “OBSERVATIONAL PROBES OF DARK ENERGY" The cause for the observed acceleration in the expansion of the universe is unknown, and referred to as "dark energy" for convenience. Dark energy could be an unknown energy component, or a modification of einstein's general relativity. This dictates The measurements that are optimal in unveiling the nature of dark energy: the cosmic expansion history, and the growth history of cosmic large scale structure. I will examine type ia supernovae and galaxy clustering as dark energy probes, and discuss recent results and future prospects. TALKS ALEJANDRO AVILES CERVANTES ICN UNAM The dark degeneracy and interacting cosmic components In this talk I present some properties of the dark degeneracy, which is the fact that what we measure in gravitational experiments is the energy-momentum tensor of the total dark sector, and any split into components (as in dark matter and dark energy) is arbitrary. In fact, just one dark fluid is necessary to obtain exactly the same cosmological and astrophysical phenomenology as the LCDM model. I work explicitly the first-order perturbation theory and show that beyond the linear order the dark degeneracy is preserved under some general assumptions. Then we construct the dark fluid from a collection of interacting fluids. Finally, I shall try to break the degeneracy with a general class of couplings to baryonic matter. Nonetheless, I show that these interactions can also be understood in the context of the LCDM model as between dark matter and baryons. ANTONIO C. C. GUIMARÃES UFRJ SNIa analysis independent of dark energy models We study alternative ways to describe the cosmic expansion that are independent of dark energy models and even independent of assumptions about the energy contend of the universe and the underlying gravitational theory. One first approach was to use kinematic models for the cosmic expansion, where we found that even very simple models allow for data fittings that are as good as ΛCDM. One second approach was to use cosmographic expansions, from what we found, among other things, that a transient cosmic acceleration is not excluded by the current SNIa data. We also use SNIa data simulations to investigate the bias that is induced by specific parameterizations of the cosmic expansion when used to analyze real data. CHRIS GAUTHIER APC Non-Parametric Reconstruction of the Primordial Power Spectrum from the CMB In my talk I propose a straightforward and model independent methodology for characterizing the sensitivity of CMB and other experiments to wiggles, irregularities, and features in the primordial power spectrum. Assuming that the primordial cosmological perturbations are adiabatic, I present a function space generalization of the usual Fisher matrix formalism, which is explicitly calculated for a number of CMB experiments. This work is closely related to other work on recovering the inflationary potential and exploring specific models of non-minimal, or perhaps baroque, primordial power spectra. The approach adopted here, however, most directly expresses what the data really is telling us. CHRISTOPH SAULDER ESO Observational aspects of an inhomogeneous cosmology One of the biggest mysteries in cosmology is Dark Energy, which is required to explain the accelerated expansion of the universe within the standard model. But maybe one can explain our observations without introducing new physics, by simply taking one step backwards and re-examining one of the basic concepts of cosmology. In standard cosmology, it is assumed that the universe is homogeneous, but this is obviously not true at small scales. Since general relativity, which is the basis of modern cosmology, is a non-linear theory, one can expect some back reactions in the case of an inhomogeneous matter distribution. The magnitude of these back reactions is a topic of hot discussion and estimates are ranging from insignificant to being perfectly able to explain the accelerated expansion of the universe. In the end, the only way to be sure is to test predictions of inhomogeneous cosmological theories, such as timescape cosmology. If it is a valid description of the universe, one expects aside other effects, that there is a dependence of the Hubble parameter on the line of sight density distribution. The redshift of a galaxy, which is located at a certain distance, is expected to be smaller if the environment in the line of sight is mainly high density (clusters or "walls"), rather than mainly low density environment (voids). It should be noted that this effect can be only observed below the scale of homogeneity and therefore, our objects of interest are rather nearby. Using the redshift and an independent distance indicator, like the fundamental plane, one is able to test this prediction. In order to get solid statistics, which can handle the uncertainties in the distance estimate and the natural scatter due to peculiar motions, one has to systematically study a very large number of galaxies. Therefore, the SDSS forms a perfect basis for testing timescape cosmology and similar theories. The preliminary results of this investigation are very interesting. DAVI CABRAL RODRIGUES UFES Elliptical galaxies kinematics within general relativity with renormalization group effects The renormalization group framework can be applied to Quantum Field Theory on curved space-time, but there is no proof whether the beta-function of the gravitational coupling indeed goes to zero in the far infrared or not. In a recent paper we have shown that the amount of dark matter inside spiral galaxies may be negligible if a small running of the General Relativity coupling G is present. Here we extend the proposed model to elliptical galaxies and present a detailed analysis on the modeling of NGC 4494 (an ordinary elliptical) and NGC 4374 (a giant elliptical). In order to compare our results to a well known alternative model to the standard dark matter picture, we also evaluate NGC 4374 with MOND. In this galaxy MOND leads to a significative discrepancy with the observed velocity dispersion curve and has a significative tendency towards tangential anisotropy. On the other hand, the approach based on the renormalization group and general relativity (RGGR) could be applied with good results to these elliptical galaxies and is compatible with lower mass-to-light ratios (of about the Kroupa IMF type). --- Based on arXiv:1203.2286v2 [astro-ph.CO]. DAVID DELEPINE UNIV. DE GUANAJUATO Heavy Majorana Neutrinos and Delta L=2 B and top decays in B factories Lepton number violation (LNV) can be induced by Majorana neutrinos in four-body decays of the neutral B meson and the top quark. We study the effects of Majorana neutrinos in these |\Delta L|=2 decays in an scenario where a single heavy neutrino can enhance the amplitude via the resonant mechanism. Using current bounds on heavy neutrino mixings, the most optimistic branching ratios turn out to be at the level of 10^{-6} for \bar{B} -> D^+e^-e^-\pi^+ and t -> bl^+l^+W^- decays. Searches for these LNV decays at future facilities can provide complementary constraints on masses and mixings of Majorana neutrinos. DEBASISH MAJUMDAR SAHA INSTITUTE OF NUCLEAR PHYSICS Gamma Ray and Neutrino Flux from Annihilation of Neutralino Dark Matter in mAMSB model We consider the lightest supersymmetric particle (LSP), neutralino in minimal anomaly mediated supersymmetry breaking model (mAMSB) to be a possible candidate for weakly interacting massive particles (WIMP) or cold dark matter and investigate its direct and indirect detections. The supersymmetric parametric space for such a model is constrained by the WMAP results for relic densities. The spin independent and spin dependent scattering cross sections for dark matter off nucleon are thus constrained from the WMAP results. They are found to be within the allowed regions of different ongoing direct detection experiments.
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