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951.
952.
Perfect State Distinguishability and Computational Speedups with Postselected Closed Timelike Curves
Bennett and Schumacher’s postselected quantum teleportation is a model of closed timelike curves (CTCs) that leads to results
physically different from Deutsch’s model. We show that even a single qubit passing through a postselected CTC (P-CTC) is
sufficient to do any postselected quantum measurement with certainty, and we discuss an important difference between “Deutschian”
CTCs (D-CTCs) and P-CTCs in which the future existence of a P-CTC might affect the present outcome of an experiment. Then,
based on a suggestion of Bennett and Smith, we explicitly show how a party assisted by P-CTCs can distinguish a set of linearly
independent quantum states, and we prove that it is not possible for such a party to distinguish a set of linearly dependent
states. The power of P-CTCs is thus weaker than that of D-CTCs because the Holevo bound still applies to circuits using them,
regardless of their ability to conspire in violating the uncertainty principle. We then discuss how different notions of a
quantum mixture that are indistinguishable in linear quantum mechanics lead to dramatically differing conclusions in a nonlinear
quantum mechanics involving P-CTCs. Finally, we give explicit circuit constructions that can efficiently factor integers,
efficiently solve any decision problem in the intersection of NP and coNP, and probabilistically solve any decision problem
in NP. These circuits accomplish these tasks with just one qubit traveling back in time, and they exploit the ability of postselected
closed timelike curves to create grandfather paradoxes for invalid answers. 相似文献
953.
We consider the flow of a viscous incompressible fluid in a pipe when the boundary is a deformable shell of Naghdi type. We
prove that the corresponding system of partial differential equations has a solution when the deformation of the shell is
smooth and small enough. We propose an algorithm that uncouples the unknowns and prove its convergence. 相似文献
954.
G. Degrassi S. Di Vita P. Slavich 《The European Physical Journal C - Particles and Fields》2012,72(6):1-11
We present a calculation of the two-loop top–stop–gluino contributions to Higgs production via gluon fusion in the MSSM. By means of an asymptotic expansion in the heavy particle masses, we obtain explicit and compact analytic formulas that are valid when the Higgs and the top quark are lighter than stops and gluino, without assuming a specific hierarchy between the Higgs mass and the top mass. Being applicable to the heaviest Higgs scalar in a significant region of the MSSM parameter space, our results complement earlier ones obtained with a Taylor expansion in the Higgs mass, and can be easily implemented in computer codes to provide an efficient and accurate determination of the Higgs production cross section. 相似文献
955.
Algirdas Matijoška Tatjana Charkova Zenonas Kuodis Vladislava Voiciuk Olegas Eicher-Lorka 《Central European Journal of Chemistry》2012,10(1):113-120
The synthesis of a new halogenide containing hexyltriethylene glycol chain functionalized with biotin is reported. The general
possibility of this linker to use as the building block for biotinylated compounds syntheses is demonstrated. Two biotinylated
esters with different properties for useful surface modification and as fluorescence probes for proteins marking were synthesized.
The properties of mentioned compounds were investigated by using surface plazmon resonance ellypsometry and fluorescence spectroscopy. 相似文献
956.
Choon Ki Ahn 《Nonlinear dynamics》2012,67(1):573-586
In this paper, a new exponential state estimation method is proposed for switched Hopfield neural networks based on passivity
theory. Through available output measurements, the main purpose is to estimate the neuron states such that the estimation
error system is exponentially stable and passive from the control input to the output error. Based on augmented Lyapunov–Krasovskii
functional, Jensen’s inequality, and linear matrix inequality (LMI), a new delay-dependent state estimator for switched Hopfield
neural networks can be achieved by solving LMIs, which can be easily facilitated by using some standard numerical packages.
The unknown gain matrix is determined by solving delay-dependent LMIs. Finally, a numerical example is provided to demonstrate
the effectiveness of the proposed method. 相似文献
957.
Background
Pitch identification had yielded unique response patterns compared to other auditory skills. Selecting one out of numerous pitches distinguished this task from detecting a pitch ascent. Encoding of numerous stimuli had activated the intraparietal sulcus in the visual domain. Therefore, we hypothesized that numerosity encoding during pitch identification activates the intraparietal sulcus as well. 相似文献958.
In this study, we present a new and very accurate numerical method to approximate the Fisher’s-type equations. Firstly, the
spatial derivative in the proposed equation is approximated by a sixth-order compact finite difference (CFD6) scheme. Secondly,
we solve the obtained system of differential equations using a third-order total variation diminishing Runge–Kutta (TVD-RK3)
scheme. Numerical examples are given to illustrate the efficiency of the proposed method. 相似文献
959.
Péter R. Surján Ágnes Szabados Péter Jeszenszki Tamás Zoboki 《Journal of mathematical chemistry》2012,50(3):534-551
Properties and some applications of strongly orthogonal geminals (APSG) are reviewed emphasizing the motivations for their
use and their shortcomings. An overview presents some techniques capable of improving the APSG function. 相似文献
960.
Hui Zhao Shinji Mitsuiki Mikako Takasugi Masashi Sakai Masatoshi Goto Hiroaki Kanouchi Tatsuzo Oka 《Applied biochemistry and biotechnology》2012,166(7):1758-1768
Insoluble and hard-to-degrade animal proteins are group of troublesome proteins, such as collagen, elastin, keratin, and prion
proteins that are largely generated by the meat industry and ultimately converted to industrial wastes. We analyzed the ability
of the abnormal prion protein-degrading enzyme E77 to degrade insoluble and hard-to-degrade animal proteins including keratin,
collagen, and elastin. The results indicate that E77 has a much higher keratinolytic activity than proteinase K and subtilisin.
Maximal E77 keratinolytic activity was observed at pH 12.0 and 65 °C. E77 was also adsorbed by keratin in a pH-independent
manner. E77 showed lower collagenolytic and elastinolytic specificities than proteinase K and subtilisin. Moreover, E77 treatment
did not damage collagens in ovine small intestines but did almost completely remove the muscles. We consider that E77 has
the potential ability for application in the processing of animal feedstuffs and sausages. 相似文献