NGC 5018, one of the weakest UV emitters among giant ellipticals (gE) observed with IUE, appears to consist of an optical stellar population very similar to that of the compact, dwarf elliptical M32, which is several magnitudes fainter in luminosity than NGC 5018 and whose stellar population is know to be ∼ 3 Gyr old. Here we show that the mid-UV spectra of these two galaxies are also very simi...

Dwarf spheroidal galaxies are the most insignificant extragalactic stellar systems in terms of their visibility, but potentially very significant in terms of their role in the formation and evolution of much more luminous galaxies. We discuss the present observational data and their implications for theories of the formation and evolution of both dwarf and giant galaxies. The putative dark matt...

We determine the imbalances of the keystreams produced by Achterbahn-80 and Achterbahn-128 in two different ways. The number of cyclically inequivalent keystreams produced by the keystream generators of Achterbahn-80 and Achterbahn-128 is determined. An abstract model for the keystream generator of a primitive NLFSR combination generator is used to justify the correlation attack introduced in [...

We study giant magnons in the the D1-D5 system from both the boundary CFT and as classical solutions of the string sigma model in AdS3 × S × T . Re-examining earlier studies of the symmetric product conformal field theory we argue that giant magnons in the symmetric product are BPS states in a centrally extended SU(1|1)×SU(1|1) superalgebra with two more additional central charges. The magnons ...

We pursue the question of multi-magnon dynamics, focusing on the simplest case of magnons moving on R × S 2 and working at the semiclassical level. Through a Pohlmeyer reduction, the problem reduces to another well known integrable field theory, the sine-Gordon model, which can be exactly described through an N-body model of Calogero type. The two theories coincide at the level of equations of ...

The controversial issue of genetically modified organisms and environmental pollution, which often leads to global warming, brings us face with the need change way agriculture leaves its mark on ecological balance. If common efforts were focused designing a multidisciplinary agricultural system that produces quantitatively nutritionally sufficient food while protecting biodiversity non-renewabl...

We discuss the observations leading to the Faint Blue Galaxy problem and the uncertainties upon which faint galaxy models are based. Using deep Hubble Space Telescope (HST) imaging with the Wide Field Planetary Camera (WFPC2), we show how morphological information has been used to shed new light on the problem. Initial results indicate that the giant galaxies (ellipticals and early-type spirals...