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    Analysis of the Jun Ishiwara's "The universal meaning of the quantum of action"

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    Here we present an analysis of the paper "Universelle Bedeutung des Wirkungsquantums" (The universal meaning of the quantum of action), published by Jun Ishiwara in German in the "Proceedings of Tokyo Mathematico-Physical Society 8 (1915) 106-116". In his work, Ishiwara, established in the Sendai University, Japan, proposed - simultaneously with Arnold Sommerfeld, William Wilson and Niels Bohr in Europe - the phase-space-integral quantization, a rule that would be incorporated into the old-quantum-theory formalism. The discussions and analysis render this paper fully accessible to undergraduate students of physics with elementary knowledge of quantum mechanics.Comment: 12 page

    Understanding the Pointer States

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    In quantum mechanics, pointer states are eigenstates of the observable of the measurement apparatus that represent the possible positions of the display pointer of the equipment. The origin of this concept lies in attempts to fill the blanks in the Everett's relative-state interpretation, and to make it a fully valid description of physical reality. To achieve this, it was necessary to consider not only the main system interacting with the measurement apparatus (like von Neumann and Everett did) but also the role of the environment in eliminating correlations between different possible measurements when interacting with the measurement apparatus. The interaction of the environment with the main system (and the measurement apparatus) is the core of the decoherence theory, which followed Everett's thesis. In this article, we review the measurement process according to von Neumann, Everett's relative state interpretation, the purpose of decoherence and some of its follow-up until Wojciech Zurek's primordial paper that consolidated the concept of pointer state, previously presented by Heinz Dieter Zeh. Employing a simple physical model consisting of a pair of two-level systems -- one representing the main system, the other the measurement apparatus -- and a thermal bath -- representing the environment -- we show how pointer states emerge, explaining its contributions to the question of measurement in quantum mechanics, as well as its limitations. Finally, we briefly show some of its consequences. This paper is accessible to readers with elementary knowledge about quantum mechanics, on the level of graduate courses.Comment: 29 pages (20 for main text and references, 9 for appendices

    Decreto nº 7.385, de 8 de dezembro de 2010 [institui o Sistema UNA-SUS]

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    Decreto que institui o Sistema Universidade Aberta do Sistema Único de Saúde - UNA-SUS, e dá outras providências

    Lei Complementar 141/2012 [Acesso universal e igualitário ao SUS]

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    Aborda as diretrizes que regulamentam o acesso ao Sistema Único de Saúde (SUS). Material produzido para utilização no curso "Responsabilidades gestoras no último ano de mandato" fornecido pela Universidade Aberta do Sistema Único de Saúde (UNA-SUS)
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