OPAL and More

We shall summarize some of the research activities performed in collaboration with Ben Shen in the OPAL experiment at LEP and in the CMS experiment at the LHC. And we shall recall the LEP legacy to particle physics in general and to the Standard Model in particular. Short recollections are made in other fields in which Ben was interested, in particular in Astroparticle Physics.Comment: Talk given at the Benjamin C. Shen Memorial Symposium, UCR, March 8, 2008. Changed reference

Hadron-hadron and hadron-nuclei collisions at high energies

A brief review is made of the present situation of hadron-hadron and hadron-nuclei total elastic and inelastic cross sections at high energiesComment: 7 page

Science,technology and society

We shall discuss some aspects of science and technology, their increasing role in the society, the fast advances in modern science, the apparent decrease of interest of the young generation in basic sciences, the importance of proper science popularization for better public education and awareness in scientific fields.Comment: Lecture at the 7th School on Non-Accelerator Astroparticle Physics, Trieste,Italy,200

RG flows with supersymmetry enhancement and geometric engineering

In this paper we study a class of $\mathcal{N}=2$ SCFTs with ADE global symmetry defined via Type IIB compactification on a class of hypersurfaces in $\mathbb{C}^3\times\mathbb{C}^*$. These can also be constructed by compactifying the 6d (2,0) theory of type ADE on a sphere with an irregular and a full punctures. When we couple to the ADE moment map a chiral multiplet in the adjoint representation and turn on a (principal) nilpotent vev for it, all the theories in this family display enhancement of supersymmetry in the infrared. We observe that all known examples of lagrangian theories which flow, upon the same type of deformation, to strongly coupled $\mathcal{N}=2$ theories fit naturally in our framework, thus providing a new perspective on this topic. We propose an infrared equivalence between this RG flow and a manifestly $\mathcal{N}=2$ preserving one and, as a byproduct, we extract a precise prescription to relate the SW curves describing the UV and IR fixed points for all theories with A or D global symmetry. We also find, for a certain subclass, a simple relation between UV and IR theories at the level of chiral algebras.Comment: clarifications added, version published in JHE

Neutrino Physics and Astrophysics with the MACRO Experiment at the Gran Sasso Lab

The results of the MACRO experiment on atmospheric neutrino oscillations are presented and discussed. The data concern different event topologies with average neutrino energies of ~ 4 and ~ 50 GeV. The Multiple Coulomb Scattering of muons in the MACRO absorbers was used to estimate the neutrino energy of each event of the higher energy sample. The angular distributions, the absolute fluxes and the L/E distribution favour nu_mu nu_tau oscillations with maximal mixing and Delta m^2=0.0025 eV^2. Results are presented on the searches for astrophysical sources of high energy muon neutrinos, for bursts of electron antineutrinos from stellar gravitational collapses and on indirect searches for WIMPs from the Earth and from the Sun.Comment: 12 pages, 10 PS and EPS figures. Invited paper at the 25^ Meeting of the Nuclear Division of the Brasilian Physical Society, S. Pedro, Brasil, 1-4 September 2002. Corrected references and sect