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Physics, Chemistry, Mathematics

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Chairman of Scientific Advisory Board: Roberto Peccei

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Enrico Bombieri: The Classical Theory of Zeta and L-functions

by Enrico Bombieri

Fields Medal in 1974 and Balzan Prize for Mathematics in 1980, and a founding member of ISSNAF

Abstract

Lecture I. Riemann's formula, zeta functions and L-functions. Summary: Beginning with Riemann's "Explicit Formula", the zeta function, Dirichlet L-functions, and the Dedekind zeta functions are introduced and their main properties are discussed. If time allows, zeta functions of modular forms and elliptic curves will be briefly introduced.

Lecture II. The analytic theory of the zeta function, known and conjectural results. Families and random matrix theory. Summary: This lecture gives a survey of results about the analytic behavior of the zeta function. The conjectural correlations of zeros and the recent conjectures about moments derived from random matrix theory will also be mentioned briefly.

Lecture III. The zeta function of curves over a finite field. Summary: This lecture is dedicated to the zeta functions of curves over a finite field and their analogy with the Dedekind zeta function. A brief sketch of Weil's first proof of the analog of the Riemann Hypothesis for them will be given. If time allows, Weil's formulation of the "Explicit Formula" will also be given. (Source: Riemann International School of Mathematics – RISM)

Related readings

The Riemann Hypothesis, Enrico Bombieri, Clay Mathematics Institute

Physics: Capasso Group

by Federico Capasso

ISSNAF founding member and professor at the Harvard School of Engineering and Applied Sciences

Capasso Group

Semiconductor Lasers with Integrated Plasmonic Polarizers

Abstract:The authors reported the plasmonic control of semiconductor laser polarization by means of metallic gratings and subwavelength apertures patterned on the laser emission facet. An integrated plasmonic polarizer can project the polarization of a semiconductor laser onto other directions. By designing a facet with two orthogonal grating-aperture structures, a polarization state consisting of a superposition of a linearly and right-circularly polarized light was demonstrated in a quantum cascade laser; a first step toward a circularly polarized laser. ©2009 American Institute of Physics

Press Coverage

Scientists demonstrate laser with controlled polarization, Harvard Press Release

Measured Long-Range Repulsive Casimir–Lifshitz Forces

Abstract: Quantum fluctuations create intermolecular forces that pervade macroscopic bodies. At molecular separations of a few nanometres or less, these interactions are the familiar van der Waals forces. However, as recognized in the theories of Casimir, Polder and Lifshitz, at larger distances and between macroscopic condensed media they reveal retardation effects associated with the finite speed of light. Although these long-range forces exist within all matter, only attractive interactions have so far been measured between material bodies. Here we show experimentally that, in accord with theoretical prediction, the sign of the force can be changed from attractive to repulsive by suitable choice of interacting materials immersed in a fluid. The measured repulsive interaction is found to be weaker than the attractive. However, in both cases the magnitude of the force increases with decreasing surface separation. Repulsive Casimir–Lifshitz forces could allow quantum levitation of objects in a fluid and lead to a new class of switchable nanoscale devices with ultra-low static friction. (Source: Nature, Jan 8, 2009)

Press Coverage

Bearing down on nanotechnology, Financial Times, Jan 9, 2009
Nuove forze repulsive, Interview with Federico Capasso, Sole 24 Ore - Nova, Jan 8, 2009
Much ado about nothing, Economist, May 2008

Astrophysics: Via Lactea: A Billion Particle Simulation of the Milky Way's Dark Matter Halo

By Piero Madau

Professor at the Department of Astronomy and Astrophysics, University of California, Santa Cruz, and a member of ISSNAF

Abstract

This project will study in unprecedented detail the formation and evolution of the dark matter halo that envelopes the Milky Way galaxy. The simulation will start at about 50 million years after the Big Bang and calculate the interactions of one billion particles of dark matter over 13.7 billion years of cosmological time to produce a halo on the same scale as the Milky Way's. It seeks to increase our understanding of the nature of the dark matter that accounts for more than 80 percent of the matter in the universe, and of the processes that make galaxy halos clumpy, i.e., teeming with gravitationally bound substructure on all resolved mass scales. (Source: The INCITE Awards) Full Text: Clumps and streams in the local dark matter distribution, Nature, August 2008 >>

Related readings

Computational Astrophysics at the NLCF, National Center for Computer Sciences
Study shows clumps and streams of dark matter in inner regions of the Milky Way, UC Santa Cruz News

Physics: Un importante premio onora due scienziati italiani in USA

By Giorgio Bellettini

ISSNAF founding member and senior professor of the University of Pisa

Two Italian CDF Physicists, Aldo Menzione and Luciano Ristori, Awarded Panofsky Prize for Establishment and Use of Silicon Detectors in a Hadron Collider. Aldo Menzione and Luciano Ristori are researchers of the Pisa INFN section. Giorgio Bellettini describes Menzione and Ristori's
foundamental contributions.

Lo scorso settembre la American Physical Society (APS), Division of Particles and Fields, ha assegnato a due ricercatori italiani della Sezione di Pisa dell’Istituto Nazionale di Fisica Nucleare (INFN), il premio W.K.H. Panofsky, anno 2009, per la Fisica delle Particelle Elementari.

“Pief” Panofsky è stato il fondatore dello Stanford Linear Accelerator Center ed una personalità eminente nella scienza nucleare sperimentale. Il premio Panofsky è stato istituito dalla APS nel 1995 “to recognize and encourage outstanding achievements in experimental particle physics”. Esso è diventato rapidamente un riconoscimento di massimo rilievo internazionale in questo campo della scienza. Prima di Aldo Menzione e Luciano Ristori lo hanno ricevuto 37 fisici, di cui uno solo italiano lo scorso anno, il prof. Italo Mannelli della Scuola Normale Superiore e della Sezione di Pisa dell’INFN.