10,155 research outputs found
Perturbative contributions to Wilson loops in twisted lattice boxes and reduced models
We compute the perturbative expression of Wilson loops up to order for
SU() lattice gauge theories with Wilson action on a finite box with twisted
boundary conditions. Our formulas are valid for any dimension and any
irreducible twist. They contain as a special case that of the 4-dimensional
Twisted Eguchi-Kawai model for a symmetric twist with flux . Our results
allow us to analyze the finite volume corrections as a function of the flux. In
particular, one can quantify the approach to volume independence at large
as a function of flux . The contribution of fermion fields in the adjoint
representation is also analyzed.Comment: pdflatex 57 pages, 9 figures, 4 appendice
A multivariate generalized independent factor GARCH model with an application to financial stock returns
We propose a new multivariate factor GARCH model, the GICA-GARCH model ,
where the data are assumed to be generated by a set of independent components (ICs).
This model applies independent component analysis (ICA) to search the conditionally
heteroskedastic latent factors. We will use two ICA approaches to estimate the ICs. The
first one estimates the components maximizing their non-gaussianity, and the second
one exploits the temporal structure of the data. After estimating the ICs, we fit an
univariate GARCH model to the volatility of each IC. Thus, the GICA-GARCH reduces
the complexity to estimate a multivariate GARCH model by transforming it into a small
number of univariate volatility models. We report some simulation experiments to show
the ability of ICA to discover leading factors in a multivariate vector of financial data.
An empirical application to the Madrid stock market will be presented, where we
compare the forecasting accuracy of the GICA-GARCH model versus the orthogonal
GARCH one
Fiesta ordenada, fiesta controlada : las tauromaquias como intento de conciliación entre razón ilustrada y razón taurina
Democedes de Crotona : biografía de un médico de finales del siglo VI a.C.
La biografía de Democedes presente en la Historia de Herodotus constituye un documento
esencial para conocer la situación de la medicina griega de finales del siglo VI a.C., así como
el papel que los médicos desempeñaban en el seno de la sociedad. Aunque Heródoto no
proporciona una datación cronológica precisa, se puede establecer una correlación cronológica
aproximada de la vida de Democedes.The biography of Democedes, present in the History of Herodotus, constitutes an essential
document to know the situation of the Greek medicine of final of the century VI B.C., as well
as for the paper that the doctors carried out in the breast of the society. Although Herodotus
doesn’t provide a precise chronology, an approximate chronological correlation of the life of
Democedes can settle establish
Daza, Josef: Precisos manejos y progresos del arte del toreo, ed. de R. Reyes Cano y P. Romero de Solís, introducción de A. González Troyano, Sevilla, Universidad y Real Maestranza de Caballería, 1999, n.º 2 de la Colección: Tauromaquia [Reseña]
La heroificación taurina. El caso de Sánchez Mejías
Ignacio Sánchez Mejías. Periodista y dramaturgo. Seminari
La circunnavegación de "Libia" : entre mito y realidad
En los inicios de la corriente de pensamiento y experiencias que abren el camino para
llegar a la geografía científica, junto al desarrollo teórico elaborado por los llamados “físicos
jonios”, encontramos una serie de empresas oceánicas que venían a confirmar en parte tales
planteamientos. El caso de la circunnavegación de África que nos presenta Heródoto constituye
un ejemplo paradigmático de este tipo de expedicionesIn the beginnings of the current of thought and experiences that open the way to come
to the scientific geography, along with the theoretical development prepared by the so-called
“ionic physicists”, we find a series of oceanic companies that were coming to confirm partly
such expositions. The case of the circumnavigation of Africa that Herodotus presents to us
constitutes a paradigmatic example of this type of expedition
La Industria algodonera catalana y el libre comercio : otra reconsideración
El papel desempeñado por el mercado americano en el proceso industrializador catalán ha constituido un elemento clave de discusión historiográfica en los últimos años. Con el presente artículo, el profesor García-Baquero añade nuevos elementos documentales a la reflexión histórica y valora positivamente la importancia que el comercio con América tuvo en el desarrollo de la industria textil catalana en las últimas décadas del Setecientos.The role played by the American market in the catalan industrializing process has been a key subject of historiographic discussion in the last years. With the present article, professor García Baquero adds new documentary elements to the historical reflection and values in a positive way the importance that had the commerce with America for the development of the Catalan textile industry in the last decades of the Eighteenth centur
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