8,149 research outputs found
Composition Operators on the Dirichlet Space and Related Problems
In this paper we investigate the following problem: when a bounded analytic
function on the unit disk , fixing 0, is such that is orthogonal in ?, and consider the
problem of characterizing the univalent, full self-maps of in
terms of the norm of the composition operator induced. The first problem is
analogous to a celebrated question asked by W. Rudin on the Hardy space setting
that was answered recently ([3] and [15]). The second problem is analogous to a
problem investigated by J. Shapiro in [14] about characterization of inner
functions in the setting of .Comment: 8 pages, 1 figure. See also
http://webdelprofesor.ula.ve/nucleotachira/gchacon or
http://webdelprofesor.ula.ve/humanidades/grchaco
A Structured Microprogram Set for the SUMC Computer to Emulate the IBM System/360, Model 50
Similarities between regular and structured microprogramming were examined. An explanation of machine branching architecture (particularly in the SUMC computer), required for ease of structured microprogram implementation is presented. Implementation of a structured microprogram set in the SUMC to emulate the IBM System/360 is described and a comparison is made between the structured set with a nonstructured set previously written for the SUMC
K^0-\bar{K}^0 mixing in the Standard Model from Nf=2+1+1 Twisted Mass Lattice QCD
We present preliminary results at {\beta} = 1.95 (a = 0.077 fm) on the first
unquenched N_f=2+1+1 lattice computation of the B_K parameter which controls
the neutral kaon oscillations in the Standard Model. Using N_f=2+1+1 maximally
twisted sea quarks and Osterwalder-Seiler valence quarks we achieve O(a)
improvement and a continuum-like renormalization pattern for the four-fermion
operator. Our results are extrapolated/interpolated to the physical
light/strange quark mass but not yet to the continuum limit. The computation of
the relevant renormalization constants is performed non perturbatively in the
RI'-MOM scheme using dedicated simulations with N_f=4 degenerate sea quark
flavours produced by the ETM collaboration.
We get B_K^{RGI} (a = 0.077) = 0.747(18), which when compared to our previous
unquenched N_f=2 determination and most of the existing results, suggests a
rather weak B_K^{RGI} dependence on the number of dynamical flavours. We are at
the moment analysing lattice data at two additional {\beta} values which will
allow us to perform an extrapolation to the continuum limit.Comment: 7 pages, 8 figures, Proceedings of Lattice 2011, XXIX International
Symposium on Lattice Field Theory, Squaw Valley, Lake Tahoe, Californi
Like my parents at home? Gender differences in children’s housework in Germany and Spain
This paper analyzes the relationship between parents’ time devoted to housework and the time devoted to housework by their children. Using data for Germany and Spain from the Multinational Time Use Study, we find positive correlations between parents’ and children’s housework time, indicating that the more time parents devote to housework, the more time their children devote to housework. However, we find cross-country differences in these relationships. In Germany, both fathers’ and mothers’ housework is positively related to the time devoted to housework by their children, while in Spain this relationship only holds for fathers’ time. We also find that these results are not applicable to all subgroups of the population, as our analysis considering the labor force status and education of the parents yields mixed results
K^0-\bar{K}^0 Mixing Beyond the SM from Nf=2 tmQCD
We present preliminary results on the of neutral kaon oscillations in
extensions of the Standard Model. Using Nf=2 maximally twisted sea quarks and
Osterwalder-Seiler valence quarks, we achieve both O(a)-improvement and
continuum-like renormalization pattern for the relevant four-fermion operators.
We perform simulations at three values of the lattice spacing and
extrapolate/interpolate our results to the continuum limit and physical
light/strange quark mass. The calculation of the renormalization constants of
the complete operator basis is performed non- perturbatively in the RI-MOM
scheme.Comment: 7 pages, 2 figures; presented at the XXVIII International Symposium
on Lattice Field Theory Villasimius, Sardinia, Ital
Association of radio polar cap brightening with bright patches and coronal holes
Radio-bright regions near the solar poles are frequently observed in Nobeyama
Radioheliograph (NoRH) maps at 17 GHz, and often in association with coronal
holes. However, the origin of these polar brightening has not been established
yet. We propose that small magnetic loops are the source of these bright
patches, and present modeling results that reproduce the main observational
characteristics of the polar brightening within coronal holes at 17 GHz. The
simulations were carried out by calculating the radio emission of the small
loops, with several temperature and density profiles, within a 2D coronal hole
atmospheric model. If located at high latitudes, the size of the simulated
bright patches are much smaller than the beam size and they present the
instrument beam size when observed. The larger bright patches can be generated
by a great number of small magnetic loops unresolved by the NoRH beam. Loop
models that reproduce bright patches contain denser and hotter plasma near the
upper chromosphere and lower corona. On the other hand, loops with increased
plasma density and temperature only in the corona do not contribute to the
emission at 17 GHz. This could explain the absence of a one-to-one association
between the 17 GHz bright patches and those observed in extreme ultraviolet.
Moreover, the emission arising from small magnetic loops located close to the
limb may merge with the usual limb brightening profile, increasing its
brightness temperature and width.Comment: 8 pages, 6 figures, 1 table. Accepted for publication in The
Astrophysical Journa
Kaon oscillations in the Standard Model and Beyond using Nf=2 dynamical quarks
We compute non-perturbatively the B-parameters of the complete basis of
four-fermion operators needed to study the Kaon oscillations in the SM and in
its supersymmetric extension. We perform numerical simulations with two
dynamical maximally twisted sea quarks at three values of the lattice spacing
on configurations generated by the ETMC. Unwanted operator mixings and O(a)
discretization effects are removed by discretizing the valence quarks with a
suitable Osterwalder-Seiler variant of the Twisted Mass action. Operators are
renormalized non-perturbatively in the RI/MOM scheme. Our preliminary result
for BK(RGI) is 0.73(3)(3).Comment: 7 pages, 3 figures, 1 table, proceedings of the XXVII Int'l Symposyum
on Lattice Field Theory (LAT2009), July 26-31 2009, Peking University,
Beijing (China
- …