On a family of strong geometric spanners that admit local routing strategies

We introduce a family of directed geometric graphs, denoted \paz, that depend on two parameters $\lambda$ and $\theta$. For $0\leq \theta<\frac{\pi}{2}$ and ${1/2} < \lambda < 1$, the \paz graph is a strong $t$-spanner, with $t=\frac{1}{(1-\lambda)\cos\theta}$. The out-degree of a node in the \paz graph is at most $\lfloor2\pi/\min(\theta, \arccos\frac{1}{2\lambda})\rfloor$. Moreover, we show that routing can be achieved locally on \paz. Next, we show that all strong $t$-spanners are also $t$-spanners of the unit disk graph. Simulations for various values of the parameters $\lambda$ and $\theta$ indicate that for random point sets, the spanning ratio of \paz is better than the proven theoretical bounds

Alternative Derivation of the Hu-Paz-Zhang Master Equation for Quantum Brownian Motion

Hu, Paz and Zhang [ B.L. Hu, J.P. Paz and Y. Zhang, Phys. Rev. D {\bf 45} (1992) 2843] have derived an exact master equation for quantum Brownian motion in a general environment via path integral techniques. Their master equation provides a very useful tool to study the decoherence of a quantum system due to the interaction with its environment. In this paper, we give an alternative and elementary derivation of the Hu-Paz-Zhang master equation, which involves tracing the evolution equation for the Wigner function. We also discuss the master equation in some special cases.Comment: 17 pages, Revte

Letter from Julia to Marie January 18, 1950

This is a letter from Julia to Marie talking about the happenings in La Paz

Paz

Ensayo que el autor hace sobre el escritor mexicano Octavio Paz. el ensayo fue publicado en la revista "La Colmena" No. 19 del año 1998, de la Universidad Autónoma del Estado de México, en la sección "Italia en la colmena", a cargo de Guillermo Fernández

Promise Arizona: Building Immigrant Political Power

This case study investigates the history and accomplishments of one organization that is making considerable strides in advancing the values and political interests of the Latino community. Beginning in 2010, Promise Arizona (PAZ) and Promise Arizona in Action (PAZ en Acción) work to empower Latinos and the immigrant community to flex their civic muscle through community organizing and political action. This case study provides a snapshot of the organization's formation, growth, and organizing initiatives and explores what strategies have been central to its success. It is one model of how grassroots organizing can contribute to achieving immigration rights

Letter from Julia to Marie May 15, 1947

This letter is about the goings on in La Paz with the Pearsons and other missionarie

Letter from Julia to family July 21, 1947

In this letter Julia talks about a recent trip to La Paz and what they did ther

Paz : notas para um estudo

Apresenta um mapeamento de alguns aspectos que devem ser aprofundados no tratamento da paz. Comenta sobre a distinção entre paz ativa e paz passiva. Discorre sobre a paz e a natureza, a paz e as categorias de solidariedade, a paz e poder, a paz e política, paz e tecnologia, paz e sujeito, paz, tolerância e hospitalidade, paz e homens de palha, paz e violência, paz e justiça. Considera que para se refletir sobre a paz, o ser humano deve ser recolocado no interior da natureza, pois a prática histórica foi a de constituir um sujeito absolutamente separado dela. Finaliza observando que a construção da paz com o ambiente e a natureza são condições de um processo emancipatório da humanidade