Cosmological constraints on Neutrino - Dark Matter interactions

I summarize the results of a recent analysis where the cosmological effects of interactions of neutrinos with cold Dark Matter (DM) is investigated. This interaction produces diffusion-damped oscillations in the matter power spectrum, analogous to the acoustic oscillations in the baryon-photon fluid. I discuss the bounds from the Sloan Digital Sky Survey on the corresponding opacity defined as the ratio of neutrino-DM scattering cross section over DM mass, and compare with the constraint from observation of neutrinos from supernova 1987A.Comment: Talk given at the Neutrino Oscillation Workshop NOW2006, Otranto, Italy, September 9-16 200

Path Integral Approach to Noncommutative Space-Times

We propose a path integral formulation of noncommutative generalizations of spacetime manifold in even dimensions, characterized by a length scale $\lambda_P$. The commutative case is obtained in the limit $\lambda_P=0$.Comment: Latex, 12 pages, updated version published in Journal of Mathematical Physics, 39, 2584-2591, 199

The future of particle physics

I review the prospects for future progress in accelerator-based particle physicsComment: Opening talk at the 10th Pisa meeting on advanced detectors, La Biodola, May 22-27 200

The saga of bottom production in proton-antiproton collisions

I review here the history of bottom quark cross section measurements and theoretical predictions. Starting form the early days of UA1, and going through the sequence of the large excesses reported during run 0 and I at the Tevatron by CDF and D0, I summarize how both data and theory have evolved in time, thanks to improved experimental techniques, more data, and improved control over the main ingredients of the theoretical calculations. I conclude with the discussion of the preliminary data from run II, which appear to finally give a satisfactory picture of the data vs theory comparison.Comment: 14 pages, Presented at the 2004 Hadron Collider Physics Workshop, East Lansing, MI, June 200

Monetary Policy in EMU : a Voting-Power Analysis of Coalition Formation in the European Central Bank

On January 1st, 1999, the European Central Bank (ECB) has started operating a common monetary policy on behalf of the 11 founding members of the European Monetary Union (EMU). There is a legitimate concern about the practicalities and the effectiveness of the decision-making process inside the ECB. This paper addresses this concern by using standard measures of voting power (as well as some of their extensions) to quantify what is likely to be the relative influence of individual EMU members on common monetary-policy decisions. Postulating the a priori formation of certain voting coalitions, it shows, among others, that the 6-member Executive Board (EB) can claim, in certain circumstances, voting power of up to 66%, but policy impact of only up to 25%, i.e. respectively much more and much less than its number of votes would imply (6 out of 17, i.e. 35.3%). Also, it is not at all clear that the 6 countries which managed to elect one of their nationals at the EB have an interest in pressing the 6 EB members to vote along national rather than EMU-wide lines, or that EMU member countries with no representative at the EB are necessarily worse off (from a voting-power perspective) when each EB member focuses on his or her own country's developments, rather than on EMU-wide aggregates.central banks; monetary policy; voting power; European Monetary Union