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241.
242.
Several illusions of vision are considered on the basis of a neurophysiological holographic model of visual perception at the level of the eye’s and the retina. It is suggested that the eye’s optical system forms a spatial spectrum of the observed object rather than its image on the retina. The spectrum is encoded by active anisotropic quasi-crystalline structures of rod rhodopsins and cone iodopsins, and a complex Fourier hologram of the observed object consisting of two quadrature components is recorded. The holographic hypothesis is confirmed by the results obtained by digital simulation.  相似文献   
243.
244.
V. Giovannetti 《Laser Physics》2006,16(10):1406-1410
Hong-Ou-Mandel interferometry allows one to detect the presence of entanglement in two-photon input states. The same result holds for two-particle input states which obey fermionic statistics. In the latter case, however, antibouncing introduces qualitative differences in the interferometer response. This effect is analyzed in a gedanken experiment where the particles entering the interferometer are assumed to belong to a one-parameter family of quons which continuously interpolate between the bosonic and fermionic statistics.  相似文献   
245.
Energy bounds of knotted and linked vortex states in a charged two-component system are considered. It is shown that a set of local minima of free energy contains new classes of universality. When the mutual linking number of vector order parameter of vortex lines is less than the Hopf invariant, these states have lower lying energies.  相似文献   
246.
The possibility of usage of the spontaneous electrooptical (EO) effect in strontium barium niobate (SBN) crystals for the creation of controlled electroholographic elements is studied. It is found that unipolar EO properties of these crystals with respect to switching their spontaneous polarization make it possible to devise field-controlled holographic elements with reversible energy-independent memory for spatial position of an optical beam.  相似文献   
247.
Bismuth, antimony and its alloys are the typical representatives of a class of semimetals, which electric conductance is lower in 102-103 times, than of usual well conducting an electrical current metals. The alloys bismuth with antimony have semi-conductor properties in wide area of compositions at temperatures below 77 °K. The semimetals are rather perspective materials from the point of view of their probable application in various devices [1,2,3].In present time the semimetal alloys BiSb have wide application in thermoelectric generators and refrigerators. In work [3] the opportunity of use of semimetals BiSb with percentage content of Bi and Sb from 8 % up to 25 % was shown as high-sensitivity and of small inertion indicators of the mm range radiation where thermoelectric effect is used. The principle of action of such indicators is based on occurrence of temperature gradient in a semimetal crystal BiSb that has two contacts of the various area with flowing electrical current. Basic element of such device is the dot contact metal - semimetal. One of the main characteristics is volt-watt sensitivity of metal-semimetal BiSb contact which calculating is shown in present work.  相似文献   
248.
We propose a simple triton wave function that consists of a product of three correlation operators operating on a three-body spin-isospin state. This wave function is formally similar to that used in the recent variational theories of nuclear matter, the main difference being in the long-range behavior of the correlation operators. Variational calculations are carried out with the Reid potential, using this wave function in the so-called “symmetrized product” and “independent pair” forms. The triton energy and density distributions obtained with the symmetrized product wave function agree with those obtained in Faddeev and other variational calculations using harmonic oscillator states. The proposed wave function and calculational methods can be easily generalized to treat the four-nucleon α-particle.  相似文献   
249.
A derivation schema in an axiomatic theory is defined as a finite sequence of analysis of applications of rules and axioms. A derivation by a schema U is any derivation whose list of analyses of applications of rules and axioms is precisely U. A derivation schema is admissible if a corresponding derivation can be constructed. Let G be a Hilbert-type axiomatic theory. The following problems are considered: a) to decide whether a given derivation scheme is admissible in G; b) to decide whether a formula is derivable by a given derivation schema in G. In the usual formulations of the predicate calculus without equality, the first problem is shown to be decidable, the second undecidable.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova Akad. Nauk SSSR, Vol. 174, pp. 132–146, 1988.  相似文献   
250.
Translated from Aktual'nye Voprosy Prikladnoi Matematiki, pp. 222–228, 1989.  相似文献   
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