955 research outputs found
Irrelevance of Bell's Theorem for experiments involving correlations in space and time: a specific loophole-free computer-example
John Bell is generally credited to have accomplished the remarkable "proof"
that any theory of physics, which is both Einstein-local and "realistic"
(counterfactually definite), results in a strong upper bound to the
correlations that are measured in space and time. He thus predicts that
Einstein-Podolsky-Rosen experiments cannot violate Bell- type inequalities. We
present a counterexample to this claim, based on discrete-event computer
simulations. Our model-results fully agree with the predictions of quantum
theory for Einstein-Podolsky-Rosen-Bohm experiments and are free of the
detection- or a coincidence-loophole
Counterfactual Definiteness and Bell's Inequality
Counterfactual definiteness must be used as at least one of the postulates or
axioms that are necessary to derive Bell-type inequalities. It is considered by
many to be a postulate that is not only commensurate with classical physics (as
for example Einstein's special relativity), but also separates and
distinguishes classical physics from quantum mechanics. It is the purpose of
this paper to show that Bell's choice of mathematical functions and independent
variables implicitly includes counterfactual definiteness and reduces the
generality of the physics of Bell-type theories so significantly that no
meaningful comparison of these theories with actual Einstein-Podolsky-Rosen
experiments can be made
Reply to the Comment by A.J. Leggett and Anupam Garg
In their comment[1] on our Letter [arXiv:0907.0767], Leggett and Garg claim
that they have introduced in their original paper (LG1) a dependence on
measurement times. They also claim that Eqs.(HMDR1) and (LG2a) can therefore
not be linked in such a way that the arguments of [arXiv:0907.0767] can be
transcribed. However, (LG1) distinguishes only three time differences, and all
experimental results corresponding to the same time differences are identically
labeled and therefore treated as mathematically identical. We therefore cannot
agree with the argumentation of Leggett and Garg: except for a change of
nomenclature Eqs.(HMDR1) and (LG2a) are the same. A more extensive discussion
of this point can be found in [arXiv:0901.2546].Comment: Published version with minor correction
Hidden assumptions in the derivation of the Theorem of Bell
John Bell's inequalities have already been considered by Boole in 1862. Boole
established a one-to-one correspondence between experimental outcomes and
mathematical abstractions of his probability theory. His abstractions are
two-valued functions that permit the logical operations AND, OR and NOT and are
the elements of an algebra. Violation of the inequalities indicated to Boole an
inconsistency of definition of the abstractions and/or the necessity to revise
the algebra. It is demonstrated in this paper, that a violation of Bell's
inequality by Einstein-Podolsky-Rosen type of experiments can be explained by
Boole's ideas. Violations of Bell's inequality also call for a revision of the
mathematical abstractions and corresponding algebra. It will be shown that this
particular view of Bell's inequalities points toward an incompleteness of
quantum mechanics, rather than to any superluminal propagation or influences at
a distance
Treatise on Invertebrate Paleontology
This volume is edited by Paul Selden, authors are Hans Hess and Charles G. Messing, coordinating author is William I. Ausich. This is the first volume to be published in an extensive revision of the Class Crinoidea. The present volume deals with the Subclass Articulata that contains all post-Paleozoic and living crinoids. The descriptions are preceded by an introduction, a chapter on the morphology of articulate crinoids, a glossary of important terms, and an overview of classification. The reference list is comprehensive for this volume.https://nsuworks.nova.edu/occ_facbooks/1009/thumbnail.jp
Extended Boole-Bell inequalities applicable to quantum theory
We address the basic meaning of apparent contradictions of quantum theory and
probability frameworks as expressed by Bell's inequalities. We show that these
contradictions have their origin in the incomplete considerations of the
premisses of the derivation of the inequalities. A careful consideration of
past work, including that of Boole and Vorob'ev, has lead us to the formulation
of extended Boole-Bell inequalities that are binding for both classical and
quantum models. The Einstein-Podolsky-Rosen-Bohm gedanken experiment and a
macroscopic quantum coherence experiment proposed by Leggett and Garg are both
shown to obey the extended Boole-Bell inequalities. These examples as well as
additional discussions also provide reasons for apparent violations of these
inequalities.Comment: Revised and extended, 31 pages, 6 figure
Left ventricular function before and after diltiazem in patients with coronary artery disease
Left ventricular contraction, relaxation and diastolic mechanics were investigated before and after intravenous administration of 15 mg of diltiazem in 15 patients with coronary artery disease. High fidelity left ventricular pressure measurements were performed in all 15 patients, with simultaneous biplane cineangiography in 13. The time constant of left ventricular isovolumic pressure decay was calculated from the linear relation of left ventricular pressure and its rate of change with time (negative dP/dt). Frame by frame volume analysis through one cardiac cycle was completed to construct volume-time and pressure-volume curves before and after the administration of diltiazem.After diltiazem, left ventricular peak systolic pressure decreased from 124 to 113 mm Hg (p < 0.001), while left ventricular end-diastolic pressure and heart rate were not altered. Maximal positive dP/dt also remained unchanged. End-diastolic volume was not changed after diltiazem, but end-systolic volume increased from 48 to 52 ml/m2(p < 0.025); as a result, ejection fraction decreased slightly from 57 to 55% (p < 0.025). The time constant of left ventricular pressure decay and maximal negative dP/dt decreased from 58 to 54 ms (p < 0.025) and from −1,404 to −1,321 mm Hg/s (p < 0.025), respectively. Peak early diastolic filling rate increased from 621 to 752 ml/s (p < 0.01) in association with an increase in filling volume during the first half of diastole from 60 to 68% (p < 0.005). No consistent displacement of the diastolic pressure-volume curve was observed after diltiazem.This study indicates that diltiazem reduces afterload and depresses myocardial contractility in patients with coronary artery disease. In contrast, it improves left ventricular relaxation, which may contribute in part to the enhancement of early diastolic filling. However, left ventricular passive diastolic properties remain uninfluenced
The market for spectacles in West Germany: Price discrimination and taxation by regulation
This thesis explains several economic phenomena in the market for spectacles which have lone confounded interested observers. Such phenomena include: 1. Prices of spectacles are almost completely uniform over the whole of West - Germany. 2. At the same time the industry is preponderately small scale. Economic theory would normally explain such pricing and industry structure either with perfect competition or in terms of a high degree of cartelization. The existence of perfect competition is ruled out for the market of spectacles and a high degree of cartelization is not normally associated with low concentration ratios and small-scale enterprises. Thus, one is lead to suspect a high degree of regulation in this health sector of the economy. As the likelihood of market failure through externalities, asymmetry of information and natural monopoly is explored it becomes obvious, however, that regulation as severe as to cause the observed pricing behaviour is not called for. The theory of taxation by regulation, developed by Richard Posner in 1971, offers an explanation. According to this theory it is often in the interest of regulators to make the regulated industry supply certain commodities or services at regulated prices below cost and subsidize these by charging above cost for commodities which are not regulated. In the case of spectacles such cross-subsidisation may take the form of price discrimination. However, aspects of price discrimination between differentiated commodities, although discussed in spatial economics, are strangely neglected by the traditional theory of price discrimination and the view is widely held that only third degree price discrimination exists in practice. Recent developments in the theory of price discrimination are presented which acknowledge that product differention may play a role and that second degree price discrimination may exist in practice. Spectacles can be seen as differentiated commodities using the Lancastrian characteristics approach. They are then viewed as bundles of characteristics, i.e. they are made up of the characteristic correction of faulty vision which they all have in common bundled with additional characteristics such as prestige through better quality frames, comfort through lightweight lenses etc. An empirical investigation reveals that a high degree of product differentiation does indeed exist in the market for spectacles and that the complex situation can only be adequately explained if the distinction between horizontal and vertical product differentiation is introduced. Posner's theory is verified empirically if it can be shown that the prices of the different varieties of the differentiated commodity spectacles are discriminatory such that the basic commodities provided at regulated prices are sold below cost and other varieties above cost. Normally, the "hedonic" method is used to test empirically for price discrimination. By defining demand-based and cost-based variables a hedonic demand and a cost schedule are obtained by multiple regression. Price differences which are due to demand influences are then taken as proof of price discrimination. In this vein a hedonic demand and a cost schedule are estimated and the existence of price discrimination in the market for spectacles is seemingly established. However, a discussion of the method reveals severe shortcomings: 1. The hedonic method does not incorporate the distinction between horizontal and vertical product differentiation. Therefore the complex pricing structure cannot be adequately described. 2. The hedonic method produces unambiguous estimates of costs of differentiated commodities only if pure competition is assumed. However, in the context of price discrimination pure competition is ruled out by definition. It is therefore necessary to develop and use a model of price discrimination which takes horizontal and vertical product differentiation into account and to employ a method of cost estimation which is valid in a monopolistic environment. The model developed in this thesis employs the Lancastrian concept of characteristics space and combines vertical and horizontal product differentiation with second and third degree price discrimination to show costs and prices in three dimensions. Prices and costs are measured on the y-axis, quantities of the differentiated varieties on the x- and z-axes. Such a three-dimensional representation produces price- and cost-planes showing exactly which varieties are sold below cost, which cover cost and which are sold above cost. As already mentioned, an unambiguous estimation of costs is essential. The relevant cost concept is that of marginal cost under full adaptation. Calculation of marginal cost is greatly facilitated if it can be shown that marginal cost is constant, for then, marginal cost equals average cost. It is shown that marginal cost is constant by constructing a long-run average cost curve and a Cobb-Douglas production function from data which the association of opticians in West Germany has collected. The costs of each individual differentiated commodity are made up of average cost and separate cost. Average and separate cost of each individual variety of spectacles were estimated in a cost study undertaken in the writer's own optical practice in Germany by methods of conventional cost accounting according to advice given by the chief cost accountant of the Volkswagen factory at Kassel. Costs of every pair of spectacles are thus determined and compared to the prices of each individual variety. It is therefore possible to construct the price- and cost-planes for a representative sample. These exhibit almost exactly the magnitude and shape that was predicted by the theoretical considerations. Thus, the empirical work confirms the theoretically derived predictions that: 1. The pricing structure of the optical profession in Germany is highly discriminatory. 2. Provision of "National Health" spectacles is cross-subsidized by revenues from spectacles sold at unregulated prices
Informe final consolidado cuenca alto magdalena, subcuenca rio Combeima 1983-1986
La Producción Bovina se considera el renglón productivo más
importante dentro de la actividad pecuaria regional y su desarrollo
está basado en el manejo adecuado de las praderas, ya que los
pastos, tanto naturales como introducidos, constituyen, la base de la
alimentación animal.
Siendo la alimentación el factor tecnológico más importante en la
producción animal, es necesario conocer los indicadores de calidad
nutricional, a partir de los nutrientes esenciales y no esenciales y la
determinación del valor nutritivo de los alimentos y forrajes
Mejoramiento nutricional en bovinos mediante la introducción de forrajes de cosecha y leguminosas de pastoreo. :informe técnico final proyecto.
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