Cosmology from Group Field Theory Formalism for Quantum Gravity

We identify a class of condensate states in the group field theory (GFT) approach to quantum gravity that can be interpreted as macroscopic homogeneous spatial geometries. We then extract the dynamics of such condensate states directly from the fundamental quantum GFT dynamics, following the procedure used in ordinary quantum fluids. The effective dynamics is a non-linear and non-local extension of quantum cosmology. We also show that any GFT model with a kinetic term of Laplacian type gives rise, in a semi-classical (WKB) approximation and in the isotropic case, to a modified Friedmann equation. This is the first concrete, general procedure for extracting an effective cosmological dynamics directly from a fundamental theory of quantum geometry

Qualification tests on the optical retro-reflectors of LARES satellite.

LARES Satellite has been successfully launched on February 13th 2012 with the first flight of the new European Launcher VEGA. The passive, laser ranged satellite carries 92 cube corner reflectors (CCR). Due to its high density LARES represents the known orbiting object with the highest mean density in the solar system. This property makes it an almost perfect proof particle in the gravitational field of Earth. LARES is now operational and it is tracked by the International Laser Ranging Service stations. It will be used to test General Relativity and in particular the fact that the rotating Earth drags spacetime. The satellite design is quite innovative in the use of tungsten alloy as a structural material; indeed, the satellite body has been machined from a single piece of high density sintered alloy. The sintered alloy is characterized by a porous surface that shall be carefully cleaned before the integration of the optical components, in order to avoid contamination of the back faces of the CCR from the metal. Two cleaning procedures have been identified, to be performed on LARES. One procedure consisted in chemical cleaning with different solvents and cleaning agents; the second procedure consisted in a chemical cleaning followed by degassing in a high vacuum oven. The cleanness procedures have been tested on breadboards reproducing the satellite materials. The breadboards were tungsten alloy cylinders, carrying a cube corner reflector. The test was performed on two different breadbords each one for one of the two cleaning procedure. To simulate the operative space conditions the Thermal Vacuum Facility of Sapienza University of Rome has been used. The breadboards were maintained in simulated space environment to allow degassing of possible contaminants from the metal and possible detachment of contaminants from the metal to the back faces of the CCR. Visual inspection and Far Field Diffraction Patter tests have been performed to verify the possible presence and effect of contaminants on the of the CCR back faces. In the paper some detail on the LARES mission and on the scientific objectives will be described along with all the details on this qualification process

Cyclic and Ekpyrotic Universes in Modified Finsler Osculating Gravity on Tangent Lorentz Bundles

We consider models of accelerating Universe elaborated for Finsler like gravity theories constructed on tangent bundles to Lorentz manifolds. In the osculating approximation, certain locally anisotropic configurations are similar to those for f(R) gravity. This allows us to generalize a proposal (by Nojiri, Odintsov and Saez-Gomez, arXiv: 1108.0767) in order to reconstruct and compare two classes of Einstein-Finsler gravity, EFG, and f(R) gravity theories using modern cosmological data and realistic physical scenarios. We conclude that EFG provides inflation, acceleration and little rip evolution scenarios with realistic alternatives to standard Lambda CDM cosmology. The approach is based on a proof that there is a general decoupling property of gravitational field equations in EFG and modified theories which allows us to generate off-diagonal cosmological solutions.Comment: latex2e, 28 pages, version accepted by CQG, with modifications and additional explanations and new references requested by referee

Towards classical geometrodynamics from Group Field Theory hydrodynamics

We take the first steps towards identifying the hydrodynamics of group field theories (GFTs) and relating this hydrodynamic regime to classical geometrodynamics of continuum space. We apply to GFT mean field theory techniques borrowed from the theory of Bose condensates, alongside standard GFT and spin foam techniques. The mean field configuration we study is, in turn, obtained from loop quantum gravity coherent states. We work in the context of 2d and 3d GFT models, in euclidean signature, both ordinary and colored, as examples of a procedure that has a more general validity. We also extract the effective dynamics of the system around the mean field configurations, and discuss the role of GFT symmetries in going from microscopic to effective dynamics. In the process, we obtain additional insights on the GFT formalism itself.Comment: revtex4, 32 pages. Contribution submitted to the focus issue of the New Journal of Physics on "Classical and Quantum Analogues for Gravitational Phenomena and Related Effects", R. Schuetzhold, U. Leonhardt and C. Maia, Eds; v2: typos corrected, references updated, to match the published versio

Hepatitis E virus (HEV) in sewage from treatment plants of Messina University Hospital and of Messina city council

Samples of sewage from treatment plants at the ?G. Martino? University Hospital of Messina (AOU) and that of Messina City Council were analysed to detect the hepatits E virus. Samples were taken on sewage entering and exiting the treat- ment plants on a monthly basis over a one-year period from both the hospital plant (24 samples) and the municipal plant (22 samples). All sewage samples were pretreated by ultrafiltraton and concen- tration and finally processed by the PCR method to amplify gene material. A total of three samples tested positive: two (8.33%) entering the AOU treatment plant and one (4.5%) entering the municipal plant while no cases of HEV were detected in samples of treated sewage. These findings confirm the presence of the virus in the city of Messina and showed that the two treatment plants to be working efficiently when tested

The Higgs mechanism in Finsler spacetimes

Finsler geometry has been recently re-discovered as an interesting possibility to describe spacetime geometry beyond Riemannian geometry. The most evident effect of this class of models is the prediction of modified dispersion relations for particles moving in such backgrounds. In this paper, we are going to consider the effects of modified dispersion relations on a gauge field theory with spontaneous symmetry breaking (SSB) associated to a Higgs field. The percolation of higher dimensional, Lorentz violating operators to lower dimensional ones is discussed. We also discuss the issue of SSB in a mono-metric Finsler scenario like the one associated to the so-called very special relativity.Comment: 11 pages, revtex

Comparison between a conventional subunit vaccine and the MF59-adjuvanted subunit influenza vaccine in the elderly: an evaluation of the safety, tolerability and immunogenicity

The objective of this study was to evaluate and compare the safety, tolerability and immunogenicity for two seasonal influ- enza subunit vaccines, one with MF59 adjuvant (Fluad?) and one without an adjuvant (Agrippal?). A total of 195 subjects aged ? 65 years were enrolled to receive one dose of vaccine intramuscularly, 96 were vaccinated with Fluad?, 99 received Agrippal?. Blood samples were taken from all subjects in order to assess their antibody titre by the haemagglutination inhibition assay (HI), before (Time 0) and after (Time 1: 28 ± 7 days) vaccination, against the A/H3N2 (A/Moscow/10/99), A/H1N1 (A/New Caledonia/20/99) and B/Shandong/7/97 antigens contained in the influenza vaccine in the 2002/2003 influenza season for the northern emisphere. A good humoral antibody response was detected for both vac- cines, meeting all the criteria of EMEA. The number of subjects in whom a ? 4-fold increase in antibody titre was recorded, in comparison with the pre-vaccination value, proved to be lower in the group vaccinated with Agrippal? than in those vaccinated with the adjuvated preparation. Fluad? exhibited better immu- nogenicity than Agrippal?. This difference was probably linked to the potentiated immune stimulation exerted by the adjuvant molecules. These results take on a particular importance if we consider that the immune system is weaker in the elderly; the admin- istration of an adjuvated vaccine in such subjects is clearly preferable in that it provides greater and more prolonged protection. Both vaccines were generally well tolerated; no severe adverse events occurred in any of the subjects vaccinated, confirming the excellent safety profile of Fluad? and Agrippa

Discrete and continuum third quantization of Gravity

We give a brief introduction to matrix models and the group field theory (GFT) formalism as realizations of the idea of a third quantization of gravity, and present in some more detail the idea and basic features of a continuum third quantization formalism in terms of a field theory on the space of connections, building up on the results of loop quantum gravity that allow to make the idea slightly more concrete. We explore to what extent one can rigorously define such a field theory. Concrete examples are given for the simple case of Riemannian GR in 3 spacetime dimensions. We discuss the relation between GFT and this formal continuum third quantized gravity, and what it can teach us about the continuum limit of GFTs.Comment: 21 pages, 5 eps figures; submitted as a contribution to the proceedings of the conference "Quantum Field Theory and Gravity Conference Regensburg 2010" (28 September - 1 October 2010, Regensburg/Bavaria); v2: preprint number include

Two-year observations of the Jupiter polar regions by JIRAM on board Juno

We observed the evolution of Jupiter's polar cyclonic structures over two years between February 2017 and February 2019, using polar observations by the Jovian InfraRed Auroral Mapper, JIRAM, on the Juno mission. Images and spectra were collected by the instrument in the 5‐μm wavelength range. The images were used to monitor the development of the cyclonic and anticyclonic structures at latitudes higher than 80° both in the northern and the southern hemispheres. Spectroscopic measurements were then used to monitor the abundances of the minor atmospheric constituents water vapor, ammonia, phosphine and germane in the polar regions, where the atmospheric optical depth is less than 1. Finally, we performed a comparative analysis with oceanic cyclones on Earth in an attempt to explain the spectral characteristics of the cyclonic structures we observe in Jupiter's polar atmosphere