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Generalizing the Heisenberg uncertainty relation
The proof of the Heisenberg uncertainty relation is modified to produce two
improvements: (a) the resulting inequality is stronger because it includes the
covariance between the two observables, and (b) the proof lifts certain
restrictions on the state to which the relation is applied, increasing its
generality. The restrictions necessary for the standard inequality to apply are
not widely known, and they are discussed in detail. The classical analog of the
Heisenberg relation is also derived, and the two are compared. Finally, the
modified relation is used to address the apparent paradox that eigenfunctions
of the z component of angular momentum L_z do not satisfy the \phi-L_z
Heisenberg relation; the resolution is that the restrictions mentioned above
make the usual inequality inapplicable to these states. The modified relation
does apply, however, and it is shown to be consistent with explicit
calculations.Comment: 12 pages, no figures. Contains corrections to errors in the published
editio
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Social medicine and international expert networks in Latin America, 1930–1945
This paper examines the international networks that influenced ideas and policy in social medicine in the 1930s and 1940s in Latin America, focusing on institutional networks organised by the League of Nations Health Organization, the International Labour Organization, and the Pan-American Sanitary Bureau. After examining the architecture of these networks, this paper traces their influence on social and health policy in two policy domains: social security and nutrition. Closer scrutiny of a series of international conferences and local media accounts of them reveals that international networks were not just ‘conveyor belts’ for policy ideas from the industrialised countries of the US and Europe into Latin America; rather, there was often contentious debate over the relevance and appropriateness of health and social policy models in the Latin American context. Recognition of difference between Latin America and the global economic core regions was a key impetus for seeking ‘national solutions to national problems’ in countries like Argentina and Chile, even as integration into these networks provided progressive doctors, scientists, and other intellectuals important international support for local political reforms
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