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[en] We discuss the possibility of performing experiments allowing one to test quantum mechanics versus any local realistic model within the context of the physics at the Φ-factory. After having sketched the main features of the physical process under consideration and having focused the locality requirements for it, we derive Bell's inequality for the two-meson system. Comparison with quantum predictions shows that the inequality is not violated for any choice of the parameters characterizing the measurement process. Contrary to the case of spin variables, there is then no way to exclude, by experiments at the Φ-factory, the possibility of a local realistic description of the process. A recent suggestion about a test of quantum predictions versus the assumption of a spontaneous factorization mechanism, as well as the claimed validity of an inequality which is different from Bell's one, are also discussed. The general conclusion is that the Φ-factory facility does not seem to open new ways of testing quantum mechanics versus alternative general schemes of the type which are usually regarded as worth considering the debate about locality and quantum mechanics. The concluding Section is devoted to making clear our position with respect to the problems discussed in this paper. It is pointed out that, in our opinion, the existing experimental evidence makes already clear that one has to accept the ''mysterious'' features of microscopic systems. The really crucial problem is that of investigating whether one can restore a coherent worldview which generally conforms with our experience at the macroscopic level, by keeping all highly successful predictions of quantum theory at the microscopic one. (author). 22 refs

[en] Three-dimensional artificial opals showing photonic crystals properties are grown by self-assembly of polystyrene nanospheres. Atomic force microscopy (AFM) images of opal surfaces show domains with regular triangular and squared packing of the spheres separated by cracks whose relative fraction depends on the sample quality. The energy position of an optical pseudo gap in transmittance spectra is observed by varying the angle of incidence and is accounted for by theoretical calculations of the photonic band structure based on a plane-wave expansion method

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No abstract available

[en] This essay begins with a comparison between Bohm's theory and the dynamical reduction program. While there are similarities (e.g., the preferred basis), there are also important differences (e.g., the type of nonlocality or of Lorentz invariance). In particular, it is made plausible that theories which exhibit parameter dependence effects cannot be ''genuinely Lorentz invariant''. For the two approaches under consideration, this analysis provides a comparison that can produce a richer understanding both of the pilot wave and of the dynamical reduction mechanism. (author). 33 refs, 1 fig

[en] Sixteen patients who had undergone the surgical resection of pharingoesophageal diverticula were investigated with combined double-contrast radiology and video-recording. In 11 patients morphological or functional anomalies were identified. The authors report their results and stress the high incidence of postoperative stenoses (18%) and recurrences (43%). The combined use of double-contrast examination and video-recording is suggested to detect such functional disorders as those which were identified in 68% of the patients in this series of cases

[en] The authors apply the distinction between parameter independence and outcome independence to the linear and nonlinear models of a recent nonrelativistic theory of continuous state vector reduction. It is shown that in the nonlinear model there is a set of realizations of the stochastic process that drives the state vector reduction for which parameter independence is violated for parallel spin components in the EPR-Bohm setup. Such a set has an appreciable probability of occurrence (∼ 1/2). On the other hand, the linear model exhibits only extremely small parameter dependence effects. Some specific features of the models are investigated and it is recalled that, as has been pointed out recently, to be able to speak of definite outcomes (or equivalently of possessed objective elements of reality) at finite times, the criteria for their attribution to physical systems must be slightly changed. The concluding section is devoted to a detailed discussion of the difficulties met when attempting to take, as a starting point for the formulation of a relativistic theory, a nonrelativistic scheme which exhibits parameter dependence. Here the authors derive a theorem which identifies the precise sense in which the occurrence of parameter dependence forbids a genuinely relativistic generalization. Finally, the authors show how the appreciable parameter dependence of the nonlinear model gives rise to problems with relativity, while the extremely weak parameter dependence of the linear model does not give rise to any difficulty, provided the appropriate criteria for the attribution of definite outcomes are taken into account. 19 refs

[en] The formulation of a relativistic theory of statevector reduction is proposed and analyzed, and its conceptual consequences are elucidated. In particular, a detailed discussion of stochastic invariance and of local and nonlocal aspects at the level of individual systems is presented. (author). 35 refs, 5 figs

[en] We discuss some features of continuous dynamical models yielding state vector reduction and we briefly sketch some recent attempts to get a relativistic generalization of them. Within the relativistic context we analyze in detail the local an nonlocal features of the reduction mechanism and we investigate critically the possibility of attributing objective properties to individual systems in the micro and macroscopic cases. At the nonrelativistic level, two physically equivalent versions of continuous reduction mechanisms have been presented. However, only one of them can be taken as a starting point for the above considered relativistic generalization. By resorting to counterfactual arguments we show that the reason for this lies in the fact that the stochasticity involved in the two approaches has different conceptual implications. (author). 7 refs, 4 figs