9,923 research outputs found
Adiabatic pumping in the quasi-one-dimensional triangle lattice
We analyze the properties of the quasi-one-dimensional triangle lattice
emphasizing the occurrence of flat bands and band touching via the tuning of
the lattice hopping parameters and on-site energies. The spectral properties of
the infinite system will be compared with the transmission through a finite
piece of the lattice with attached semi-infinite leads. Furthermore, we
investigate the adiabatic pumping properties of such a system: depending on the
transmission through the lattice, this results in nonzero integer charge
transfers or transfers that increase linearly with the lattice size
Strange hadronic stellar matter within the Brueckner-Bethe-Goldstone theory
In the framework of the non-relativistic Brueckner-Bethe-Goldstone theory, we
derive a microscopic equation of state for asymmetric and -stable matter
containing and hyperons. We mainly study the effects of
three-body forces (TBFs) among nucleons on the hyperon formation and the
equation of state (EoS). We find that, when TBFs are included, the stellar core
is almost equally populated by nucleons and hyperons. The resulting EoS, which
turns out to be extremely soft, has been used in order to calculate the static
structure of neutron stars. We obtain a value of the maximum mass of 1.26 solar
masses (1 solar mass ). Stellar rotations
increase this value by about 12%.Comment: 4 pages, Latex, 2 figures included. To appear in the Proceedings of
'' Bologna 2000 - Structure of the Nucleus at the Dawn of the Century'', May
29- June 3, 2000, Bologna, Ital
Modelling linguistic taxonomic dynamics
This paper presents the results of the application of a bit-string model of
languages (Schulze and Stauffer 2005) to problems of taxonomic patterns. The
questions addressed include the following: (1) Which parameters are minimally
ne eded for the development of a taxonomic dynamics leading to the type of
distribution of language family sizes currently attested (as measured in the i
number of languages per family), which appears to be a power-law? (2) How may
such a model be coupled with one of the dynamics of speaker populations leading
to the type of language size seen today, which appears to follow a log-normal
distribution?Comment: 18 pages including 9 figure
Direct Measurement of the g-Factor of Composite Fermions
The activation gap of the fractional quantum Hall states at constant
fillings and 2/5 has been measured as a function of the
perpendicular magnetic field . A linear dependence of on is
observed while approaching the spin polarization transition. This feature
allows a direct measurement of the -factor of composite fermions which
appears to be heavily renormalized by interactions and strongly sensitive to
the electronic filling factor.Comment: 4 pages, 4 figures Changed content: Fokus more on g-factors (and less
on other details
Structure of the hadron-quark mixed phase in protoneutron stars
We study the hadron-quark phase transition in the interior of hot
protoneutron stars, combining the Brueckner-Hartree-Fock approach for hadronic
matter with the MIT bag model or the Dyson-Schwinger model for quark matter. We
examine the structure of the mixed phase constructed according to different
prescriptions for the phase transition, and the resulting consequences for
stellar properties. We find important effects for the internal composition, but
only very small influence on the global stellar properties.Comment: 6 pages, 4 figure
Calvyn en die Akademie van Geneve
In this article Calvin's founding of the College and Academy of Geneva (1559) is discussed against the background of the medieval school system in order to appreciate his part in the renewal of education. Imbibing the humanism of his day, Calvin's engagagement with education reveals common ground with the humanist ideals of his limes. Yet there were fundamental differences: by combining the classical artes liberates with the study of God’s Word, his ideal was not the creation of better human beings through education (the ideal of humanism) but the formation of useful men and women in the kingdom of God, i.e in church and society. Some stipulations of his church order (1541) and Leges for the Academy are placed in the context of his theology. Finally, Calvin’s ideals and contribution to education challenge us to consider our choices for education in a 'new South Africa’
- …