Hemeroteca del mes octubre, 2013

A Pax Sinica in the Middle East?

Por • 30 oct, 2013 • Category: Política

English-language media completely ignored a noteworthy statement that led Der Spiegel’s German-language website October 12, a call for China to “take on responsibility as a world power” in the Middle East. Penned by Bernhard Zand, the German news organization’s Beijing correspondent, it is terse and to the point: now that China imports more oil from the Middle East than any other country in the world, it must answer for the region’s security. “America’s interest in the Middle East diminishes day by day” as it heads towards energy self-sufficiency, wrote Zand, adding: China’s interest in a peaceful Middle East is enormous, by contrast. Beijing is not only the biggest customer of precisely those oil powers who presently are fanning the flames of conflict in Syria; as a VIP customer, Beijing has growing political influence, which it should use openly. The word of the Chinese foreign minister has just as much weight in Tehran and Riyadh as that of his American counterpart.



A statistical physics perspective on criticality in financial markets

Por • 28 oct, 2013 • Category: Ambiente

Stock markets are complex systems exhibiting collective phenomena and particular features such as synchronization, fluctuations distributed as power-laws, non-random structures and similarity to neural networks. Such specific properties suggest that markets operate at a very special point. Financial markets are believed to be critical by analogy to physical systems but few statistically founded evidence have been given. Through a data-based methodology and comparison to simulations inspired by statistical physics of complex systems, we show that the Dow Jones and indices sets are not rigorously critical. However, financial systems are closer to the criticality in the crash neighborhood.



BCV incrementa financiamiento a Pdvsa e impulsa la inflación

Por • 28 oct, 2013 • Category: Nacionales

Para que la inflación tome vuelo y el dólar se incremente en el mercado paralelo es necesario que existan más bolívares de los que la economía quiere y la fuente principal del exceso de billetes es que el Banco Central imprime dinero sin respaldo para financiar a Pdvsa y a otras empresas públicas a un ritmo cada vez más acelerado.



Rafael Ramírez: Le declaramos la guerra al dólar paralelo

Por • 28 oct, 2013 • Category: Nacionales

“El cadivismo es una perforación al sistema financiero del país y el que esté vinculado a la corrupción y desfalco de la nación, está en contra de la revolución. Es por ello que estamos en nuevo sistema de reestructuración”. El Ministro enfatizó que el mercado del dólar paralelo no es alimentado por el pueblo, sino por los grandes sectores de la burguesía que ostenta el poder económico, “porque ellos son los que tienen un interés político particular y lo que pretenden con esto es desestabilizar el país”.
Acotó que la corrupción no sólo se da en el ámbito del sector público, sino en el privado, ya que “hay una clase económica corrupta que se adueña de la renta de los venezolanos, a través de las divisas que asigna el Estado mediante Cadivi, y pretenden que les entreguemos el manejo de los dólares, y eso no va a suceder”.



Transfinite Recursion in Higher Reverse Mathematics

Por • 27 oct, 2013 • Category: Educacion

In this paper we investigate the reverse mathematics of higher-order analogues of the theory \ATRz{} within the framework of higher order reverse mathematics developed by Kohlenbach \cite{Koh01}. We define a theory \RCAzthr, a close higher-type analogue of the classical base theory \RCAz, and show that it is essentially a conservative subtheory of Kohlenbach’s base theory \RCAzo. Working over \RCAzthr, we study higher-type analogues of statements classically equivalent to \ATRz, including open and clopen determinacy, as well as two choice principles, and prove several equivalences and separations. Our main result is the separation of open and clopen determinacy for reals, using a variant of Steel forcing; in the presentation of this result, we develop a new, more flexible framework for Steel-type forcing.



Partial Probability and Kleene Logic

Por • 27 oct, 2013 • Category: Crítica

There are two main approach to probability, one of set-theoretic character where probability is the measure of a set, and another one of linguistic character where probability is the degree of confidence in a proposition. In this work we give an unified algebraic treatment of these approaches through the concept of valued lattice, obtaining as a by-product a translation between them. Then we introduce the concept of partial valuation for DMF-algebras (De Morgan algebras with a single fixed point for negation), giving an algebraic setting for probability of partial events. We introduce the concept of partial probability for propositions, substituting classical logic with Kleene’s logic. In this case too we give a translation between set-theoretic and linguistic probability. Finally, we introduce the concept of conditional partial probability and prove a weak form of Bayes’s Theorem.



Symbolic Toolkit for Chaos Explorations

Por • 27 oct, 2013 • Category: Ciencia y tecnología

New computational technique based on the symbolic description utilizing kneading invariants is used for explorations of parametric chaos in a two exemplary systems with the Lorenz attractor: a normal model from mathematics, and a laser model from nonlinear optics. The technique allows for uncovering the stunning complexity and universality of the patterns discovered in the bi-parametric scans of the given models and detects their organizing centers — codimension-two T-points and separating saddles.



A Thousand Problems in Cosmology: Horizons

Por • 27 oct, 2013 • Category: Opinion

This is one chapter of the collection of problems in cosmology, in which we assemble the problems that concern one of the most distinctive features of general relativity and cosmology—the horizons. The first part gives an elementary introduction into the concept in the cosmological context, then we move to more formal exposition of the subject and consider first simple, and then composite models, such as Λ CDM. The fourth section elevates the rigor one more step and explores the causal structure of different simple cosmological models in terms of conformal diagrams. The section on black holes relates the general scheme of constructing conformal diagrams for stationary black hole spacetimes. The consequent parts focus on more specific topics, such as the various problems regarding the Hubble sphere, inflation and holography.
This version contains only formulations of 97 problems. The full collection, with solutions included, is available in the form of a wiki-based resource at this http URL The cosmological community is welcome to contribute to its development.



How NSA Penetrated Latin America Telecommunications Networks

Por • 26 oct, 2013 • Category: Política

NSA’s widespread collection of digital data from fiber-optic lines, Internet Service Providers, telecommunications companies’ network switches, and cellular systems in Latin America could not have been possible without the presence of intelligence assets within telecommunications companies and other network service providers. Among the Five Eyes signals intelligence (SIGINT) sharing nations of the United States, Britain, Australia, Canada, and New Zealand, such cooperation from the commercial firms is relatively easy. They cooperate with their nations’ respective SIGINT agencies to either gain favor or avoid retaliation from their governments. In the United States, NSA enjoys the cooperation of Microsoft, AT&T, Yahoo, Google, Facebook, Twitter, Apple, Verizon, and others to carry out massive surveillance conducted by the PRISM metadata collection program.



Calderón, el soñador despierto

Por • 26 oct, 2013 • Category: Filosofía

De cómo en Calderón la hipótesis del sueño y del genio maligno sigue un camino en sentido contrario al de Descartes y los filósofos europeos. En todo caso la figura central de la contrarreforma, que además proporcionará las ideas centrales de la futura filosofía y de la literatura es Francisco Suárez, que vive y piensa en la encrucijada de los dos siglos XVI y XVII. Ingresa en la Compañía de Jesús, y después de estudiar en Salamanca filosofía y teología profesa en Valladolid y Segovia ya en la década de 1570-80. Como todos los otros teólogos de la Compañía toma parte en la controversia De Auxiliis, y polemiza también con los reformistas anglicanos en un panfleto de 1613, y de una forma indirecta pero más eficaz en su tratado De legibus –1612 Coimbra– donde separa el poder religioso, venido de Dios, y la soberanía política de cada pueblo, que pone al rey o lo quita, si no cumple sus funciones rectamente. En fin, escribe también un tratado de psicología con el nombre tópico De Anima, que sólo se publica cuatro años después de su muerte, en 1621. Pero la influencia de Suárez será también decisiva en el pensamiento del barroco español. Es cierto que los géneros literarios por medio de los cuales se trasmite y comunica son formalmente diferentes de los tratados filosóficos y científicos que fundamentan y desarrollan en todo el continente la astronomía nueva y la física matemática. Los españoles siguen siendo impacientes y teatrales y cambian con gusto la monotonía de los razonamientos demostrativos propios de las ciencias exactas por otras figuras de representación, como los relatos novelados, la pintura y la imaginería, y sobre todo las obras compuestas por sus dramaturgos.