| [1] |
Stephen Blaha.
A classical probabilistic computer model of consciousness, 2002. BibTeX entry, Available here, PDF
We show that human consciousness can be modeled as a classical (not quantum) probabilistic computer. A quantum computer representation does not appear to be indicated because no known feature of consciousness depends on Planck's constant h, the telltale sign of quantum phenomena. It is argued that the facets of consciousness are describable by an object-oriented design with dynamically defined classes and objects. A comparison to economic theory is also made. We argue consciousness may also have redundant, protective mechanisms.
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| [2] |
Bertrand Duplantier.
Introduction à l'effet casimir.
Séminaire Poincaré, 1:41-54, 2002. BibTeX entry, Available here, Compressed PS |
| [3] |
Maria Vittoria Garzelli and Carlo Giunti.
Bayesian view of solar neutrino oscillations.
Journal of High Energy Physics, 2001(12):017, 2001. BibTeX entry, Available here, PDF
We present the results of a bayesian analysis of solar neutrino data in terms of ν e &to;νμ,τ and ν e &to;ν s oscillations, where ν s is a sterile neutrino. We perform a Rates Analysis of the rates of solar neutrino experiments, including the first SNO CC result, and spectral data of the CHOOZ experiment, and a Global Analysis that takes into account also the Super-Kamiokande day and night electron energy spectra. We show that the bayesian analysis of solar neutrino data does not suffer any problem from the inclusion of the numerous bins of the CHOOZ and Super-Kamiokande electron energy spectra and allows to reach the same conclusions on the favored type of neutrino transitions and on the determination of the most favored values of the oscillation parameters in both the Rates and Global Analysis. Our bayesian analysis shows that ν e &to;ν s transitions are strongly disfavored with respect to ν e &to;νμ,τ transitions. In the case of ν e &to;νμ,τ oscillations, the Large Mixing Angle region is favored by the data (86&percent; probability), the LOW region has some small chance (13&percent; probability), the Vacuum Oscillation region is almost excluded (1&percent; probability) and the Small Mixing Angle region is practically excluded (0.01&percent; probability). We calculate also the marginal posterior probability distributions for tan2 ϑ and Δ m 2 in the case of ν e &to;νμ,τ oscillations and we show that the data imply large mixing almost with certainty and large values of Δ m 2 are favored (2 × 10−6 eV2 < Δ m 2 < 10−3 eV2 with 86&percent; probability). We present also the results of a standard least-squares analysis of solar neutrino data and we show that the standard goodness of fit test is not able to reject pure ν e &to;ν s transitions. The likelihood ratio test, which is insensitive to the number of bins of the CHOOZ and Super-Kamiokande energy spectra, allows to reject pure ν e &to;ν s transitions in favor of ν e &to;νμ,τ transitions only in the Global Analysis.
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| [4] |
Samir Mezouari and Andy Robert Harvey.
Validity of fresnel and fraunhofer approximations in scalar
diffraction.
Journal of Optics A: Pure and Applied Optics, 5(4):S86-S91,
2003. BibTeX entry, PDF
Evaluation of the electromagnetic fields diffracted from plane apertures are, in the general case, highly problematic. Fortunately the exploitation of the Fresnel and more restricted Fraunhofer approximations can greatly simplify evaluation. In particular, the use of the fast Fourier transform algorithm when the Fraunhofer approximation is valid greatly increases the speed of computation. However, for specific applications it is often unclear which approximation is appropriate and the degree of accuracy that will be obtained. We build here on earlier work (Shimoji M 1995 Proc. 27th Southeastern Symp. on System Theory (Starkville, MS, March 1995) (Los Alamitos, CA: IEEE Computer Society Press) pp 520–4) that showed that for diffraction from a circular aperture and for a specific phase error, there is a specific curved boundary surface between the Fresnel and Fraunhofer regions. We derive the location of the boundary surface and the magnitude of the errors in field amplitude that can be expected as a result of applying the Fresnel and Fraunhofer approximations. These expressions are exact for a circular aperture and are extended to give the minimum limit on the domain of validity of the Fresnel approximation for plane arbitrary apertures.
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