The Adiabatic Theorem for Quantum Systems with Spectral Degeneracy

By stating the adiabatic theorem of quantum mechanics in a clear and rigorous way, we establish a necessary condition and a sufficient condition for its validity, where the latter is obtained employing our recently developed adiabatic perturbation theory. Also, we simplify further the sufficient condition into a useful and simple practical test at the expenses of its mathematical rigor. We present results for the most general case of quantum systems, i.e., those with degenerate energy spectra. These conditions are of upmost importance to assess the validity of practical implementations of non-Abelian braiding and adiabatic quantum computation. To illustrate the degenerate adiabatic approximation, and the necessary and sufficient conditions for its validity, we analyze in depth an exactly solvable time-dependent degenerate problem.Comment: 4 pages, no figures, RevTex4-1; v2: published versio

El problema de la validación de conocimientos en la sociología

En una primara parte, introduciré el problema enunciado en el título de esta comunicación valiéndome del análisis del término validación, lo haré en función de los usos que el mismo tiene en contextos lingüísticos específicos. Inmediatamente, diré algo acerca de cómo la validez o validación de conocimientos en ciencia social (que de eso se trata en nuestro caso), pertenecen al área de la filosofía que algunos llaman epistemología y otros metodología. Por último -y siempre dentro de esa primera parte- añadiré un par de reflexiones acerca de la relación entre la fundamentación y la validación de conocimientos

Adiabatic Perturbation Theory and Geometric Phases for Degenerate Systems

We introduce an adiabatic perturbation theory for quantum systems with degenerate energy spectra. This perturbative series enables one to rigorously establish conditions for the validity of the adiabatic theorem of quantum mechanics for degenerate systems. The same formalism can be used to find non-adiabatic corrections to the non-Abelian Wilczek-Zee geometric phase. These corrections are relevant to assess the validity of the practical implementation of the concept of fractional exchange statistics. We illustrate the formalism by exactly solving a time-dependent problem and comparing its solution to the perturbative one.Comment: 5 pages, no figures, RevTex4; v2: published versio

Baryon spectroscopy in the unquenched quark model

We discuss some applications of the unquenched quark model which is an extension of the CQM that includes the effects of sea quarks via a 3P0 quark-antiquark pair-creation mechanism. Particular attention is paid to the electromagnetic couplings and beta decays of baryons. It is shown that the observed discrepancies between the experimental data and the predictions of the CQM can be accounted for in large part by the effects of sea quarks in the unquenched quark model.Comment: 5 pages, 2 figures, 2 tables, invited talk at XVII International Conference on Hadron Spectroscopy and Structure, submitted for publication in Proceedings of Scienc

The issue of social politicization in García Linera

Álvaro García Linera, es uno de los líderes políticos más importantes de la región, cuyo pensamiento y praxis política en Bolivia, nos permite analizar las causas y consecuencias del regreso de un nuevo oleaje neoliberal en latinoamérica. El intelectual ha propuesto la mirada crítica sobre las debilidades de los gobiernos progresistas de inicios de la presente década, y una de ellas, la que será objeto de esta investigación, refiere que la distribución de riqueza pública es ineficiente sin la politización social de las sociedades o comunidades. Descubriremos través de un recorrido de sus publicaciones académicas y entrevistas realizadas, los rasgos teóricos y empíricos de politicidad, señalando las experiencias bolivianas de la nación indígena Aymará como de otras iniciativas colectivas como Multitud; examinando además, los argumentos por el cuál es necesario superar el sentido común conservador, en el marco de la lucha por la hegemonía cultural.Álvaro García Linera, is one of the most important political leaders in the region, whose thought and political praxis in Bolivia, allows us to analyze the causes and consequences of the return of a new neoliberal wave in latin América. The intellectual has proposed a critical look at the weaknesses of the progressive governments of the beginning of this decade, and one of them, which will be the subject of this research, refers that the distribution of public wealth is inefficient without politicization Society or communities. We will discover through a tour of their academic publications and interviews, the theoretical and empirical features of politicity, pointing out the Bolivian experiences of the Aymara Indigenous nation as well as other collective initiatives as a multitude; further examining the arguments for which it is necessary to overcome conservative common sense in the context of the struggle for cultural hegemony.Fil: Ortiz, Gustavo David. Universidad Nacional de Cuy