Search results for "Conti"

Explicit results for all orders of the epsilon-expansion of certain massive and massless diagrams

2000

An arbitrary term of the epsilon-expansion of dimensionally regulated off-shell massless one-loop three-point Feynman diagram is expressed in terms of log-sine integrals related to the polylogarithms. Using magic connection between these diagrams and two-loop massive vacuum diagrams, the epsilon-expansion of the latter is also obtained, for arbitrary values of the masses. The problem of analytic continuation is also discussed.

Abelian current algebra and the Virasoro algebra on the lattice

1993

We describe how a natural lattice analogue of the abelian current algebra combined with free discrete time dynamics gives rise to the lattice Virasoro algebra and corresponding hierarchy of conservation laws.

Inverse symmetry breaking and the exact renormalization group

1996

We discuss the question of inverse symmetry breaking at non-zero temperature using the exact renormalization group. We study a two-scalar theory and concentrate on the nature of the phase transition during which the symmetry is broken. We also examine the persistence of symmetry breaking at temperatures higher than the critical one.

Dynamical Abelian Projection of Gluodynamics

1996

Assuming the monopole dominance, that has been proved in the lattice gluodynamics, to hold in the continuum limit, we develop an effective scalar field theory for QCD at large distances to describe confinement. The approach is based on a gauge (or projection) independent formulation of the monopole dominance and manifestly Lorentz invariant.

Síntesis de los estudios sobre moluscos continentales neógenos del sector septentrional de la Depresión de Teruel: período 1775-1998

2006

Se recopila y analiza la información que se considera más relevante y se encuentra contenida en los estudios realizados sobre el registro fósil de los moluscos neógenos del sector septentrional de la Depresión de Teruel en el período comprendido entre los años 1775 y 1998. Se contabilizan, por una parte, el número total de taxones diferentes mencionados en cada trabajo y, por otra, sólo el número de citas efectuadas a nivel de especie en cada uno de ellos. Estas últimas se organizan en tres categorías que reciben el nombre de citas nuevas, especies nuevas y citas repetidas. Se propone, a partir de la información contenida en cada trabajo, el número de taxones contemplados, y la tipología de…

History teaching: real problems and interessed polemics

2006

En diversos países se ha tratado de poner límites a las innovaciones educativas, de diverso calado, que se estaban produciendo en la enseñanza de la historia, con la intención de retornar a un modelo de enseñanza más próximo a sus características tradicionales, a pesar de las muy razonadas críticas que este modelo tradicional había recibido. Las razones aducidas para tal reversión han variado de un país a otro, pero el objetivo compartido ha sido el de establecer unos programas más dirigistas y cerrados, de tipo marcadamente enciclopédico, en los que las posibilidades de actuación innovadora del profesorado, por una parte, y las de un aprendizaje más razonado del alumnado, por la otra, qued…

The geography of the Rendiconti del Circolo Matematico di Palermo: local and international aspect

The Mathematical Circle of Palermo, founded in 1884 by 27 mathematicians all living in Palermo, became the publisher of the prestigious magazine "Rendiconti", which in thirty years became one of the leading international mathematical journals. In this talk, we will analyze the evolution of the components of the Societies and of Rendiconti towards internationalization from 1884 to 1914. Moreover, we will try to extract from the statistical data some considerations about the possible causes of the identified internationalization process

Pedagoģijas zinātnes ģenēze Latvijā no 20.gadsimta 20.gadiem līdz 60.gadu sākumam

2013

ANOTĀCIJA Ivetas Ozolas promocijas darba „Pedagoģijas zinātnes ģenēze Latvijā no 20. gadsimta 20. gadiem līdz 60. gadu sākumam” mērķis ir izpētīt, kā sociālpolitisku un zinātnes procesu kontekstā pedagoģija Latvijā laika posmā no 20. gadsimta 20. gadiem līdz 60. gadu sākumam veidojusies un attīstījusies kā patstāvīga zinātnes nozare. Darbā analizēti zinātnes veidošanās teorētiskie pamati, definējot dimensijas, kas raksturo atsevišķu zinātnes nozaru izveidošanos. Atbilstoši tām pētīta pedagoģijas zinātnes institucionālās, komunikatīvās un metodoloģiskās dimensijas attīstība Latvijā dažādu pedagoģijas paradigmu un sociālpolitisko apstākļu kontekstā. Pētījuma rezultāti apliecina, ka pedagoģija…

The “Circolo Matematico di Palermo” and the First World War: The crisis of scientific internationalism: a view through the unedited correspondence of…

2021

Abstract In this work the situation of the “Circolo Matematico di Palermo” between 1914 and 1928 is analyzed. It will be observed that during this time the Circolo was among the few European scientific associations with German as well as French associates. During the 1930s, the nationalist politics of Fascism and above all the racial laws dealt a deadly blow to the Circolo as an international scientific association. We will use the rich correspondence in the Circolo's archives to shed some light on this. In particular, the correspondence between M. De Franchis and E. Landau and other recently found documents will figure prominently.

Supercontinuum generation in Ge-doped Y-shaped microstructured tapered fiber

2011

We have investigated the generation of supercontinuum in tapered Y-shaped fibers in the nanosecond pump regime. This fiber used to fabricate the tapers has, in addition, a Ge-doped core which enhances the nonlinearity of the material and the Raman gain. The fiber was pumped at 1064 nm in the ns pump regime (0.6 ns pulses and up to 3.2 kW peak power). The taper had a uniform waist of 0.9 μm diameter and 130 mm length, and the adiabatic transitions were 110 mm long. A flat spectrum spanning from 420 nm to 1870 nm was obtained using a single tapered fiber.