We discuss O'Raifeartaigh models with general R-charge assignments, introduced by Shih to break R-symmetry spontaneously. We argue that most of these models have runaway directions related to the R-symmetry. In addition, ...

We discuss a symmetric setup for a reactor neutrino oscillation experiment consisting of two reactors separated by about 1 km, and two symmetrically placed detectors, one close to each reactor. We show that such a configuration ...

Rolling lubrication with spherical molecules working as 'nanobearings' has failed experimentally so far, without a full understanding of the physics involved and of the reasons why. Past model simulations and common sense ...

We prove the existence of radial solutions of 1.2) concentrating at a sphere for potentials which might be zero and might decay to zero at infinity. The proofs use a perturbation technique in a variational setting, through ...

We evaluate the branching ratios of the radiative decays $B \to K^* \gamma $, and $B \to K_1 \gamma $ in the framework of three-point function QCD sum rules. We find: $ \Gamma(B \to K^* \gamma) / \Gamma(b \to s \gamma) = ...

The next-to-leading--logarithmic corrections to the helicity cross- sections for the Drell-Yan process are calculated. While it is well-known that these corrections are large, it is shown here that when considering the ...

Strong observational evidence for a fluctuating ultraviolet background (UVB) has been accumulating through a number of studies of the HI and HeII Lya forest as well as accurate IGM metallicity measurements. UVB fluctuations ...

By collecting the information from 24 previously published lists and catalogs, we produce a comprehensive catalog (Master Catalog) of 1442 Galactic HII regions. For each object, we quote the original fluxes and diameters ...