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Communications in Theoretical Physics 2015年第6期63卷 687-694页

作者： alexey e.rastegin Department of Theoretical Physics Irkutsk State University

We study uncertainty and certainty relations for two successive measurements of two-dimensional observables. Uncertainties in successive measurement are considered within the following two scenarios. In the first scenario, the second measurement is performed on the quantum state generated affer the first measurement with completely erased information. In the second scenario, the second measurement is performed on the post-first- tioned on the actual measurement outcome. Induced entropies. For two successive projective t state condiquantum uncertainties are characterized by means of the Tsallis t of a qubit, we obtain minimal and maximal values of related entropic measures of induced uncertainties. Some conclusions found in the second scenario are extended to arbitrary finite dimensionality. In particular, a connection with mutual unbiasedness is emphasized.

关键词： successive measurements Tsallis entropy uncertainty principle purity

Uncertainty and Certainty Relations for Pauli Observables in Terms of R′enyi entropies of Order α ∈(0;1]

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Communications in Theoretical Physics 2014年第3期61卷 293-298页

作者： alexey e.rastegin Department of Theoretical Physics Irkutsk State University

We obtain uncertainty and certainty relations of state-independent form for the three Paufi observables with use of the Renyi entropies of order α∈ （0; 1]. It is shown that these entropic bounds are tight in the sense that they are always reached with certain pure states. A new result is the condition for equality in Renyi-entropy uncertainty relations for the Pauli observables. Upper entropic bounds in the pure-state case are also novel. Combining the presented bounds leads to a band, in which the rescaled average Renyi a-entropy ranges for a pure measured state. A width of this band is compared with the Tsallis formulation derived previously.

关键词： Pauli observables Renyi entropy quantum measurement uncertainty principle

Formulation of Leggett–Garg Inequalities in Terms of q-entropies

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Communications in Theoretical Physics 2014年第9期61卷 320-326页

作者： alexey e. rastegin Department of Theoretical Physics Irkutsk State University Gagarin Bv. 20 Irkutsk 664003 Russia

As is well known, the macroscopic realism and the noninvasive measurability together lead to Leggett–Garg inequalities violated by quantum mechanics. We consider tests of the Leggett–Garg type with use of the *** all q≥1, quantum mechanics predicts violations of an entire family of q-entropic inequalities of the Leggett–Garg type. Violations are exemplified with a quantum spin-s system. In general, entropic Leggett–Garg inequalities give only necessary conditions that some probabilistic model is compatible with the macrorealism in the broader sense. The presented q-entropic inequalities allow to widen a class of situations, in which an incompatibility with the macrorealism can be tested. In the considered example, both the strength and range of violations are somehow improved by varying *** also examine q-entropic inequalities of the Leggett–Garg type in the case of detection inefficiencies, when the no-click event may occur in each observation. With the use of the q-entropic inequalities, the required amount of efficiency may be reduced.

关键词： Bell theorem Leggett–Garg inequalities macrorealism noninvasive measurability conditional q-entropies

Degradation of Grover＇s search under collective phase flips in queries to the oracle

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Frontiers of physics 2018年第5期13卷 271-279页

作者： alexey e. rastegin Department of Theoretical Physics Irkutsk State University Irkutsk Russia

We address the case in which querying the oracle in Grover＇s algorithm is exposed to noise including phase distortions. The oracle-box wires can be altered by an opposing party that tries to prevent reception of correct data from the oracle. This situation reflects an experienced truth that any access to prophetic knowledge cannot be common and direct. To study this problem, we introduce a simple model of collective phase distortions on the basis of a phase-damping channel. In the model, the probability of success is not altered via the oracle-box wires per se. Phase distortions of the considered type can hardly be detected via any one-time query to the oracle. However, the probability of success is significantly changed when such errors are introduced as an intermediate step in the Grover iteration. We investigate the probability of success with respect to variations of the parameter that characterizes the amount of phase errors. It turns out that the probability of success decreases significantly even if the error is not very high. Moreover, this probability quickly reduces to the value of one half, which corresponds to the completely mixed state. We also study trade-off relations between quantum coherence and the probability of success in the presence of noise of the considered type.

关键词： Grover's algorithm phase noise relative entropy of coherence

Uncertainty relations for quantum coherence with respect to mutually unbiased bases

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Frontiers of physics 2018年第1期13卷 179-185页

作者： alexey e. rastegin Department of Theoretical Physics Irkutsk State University Russia

The concept of quantum coherence, including various ways to quantify the degree of coherence with respect to the prescribed basis, is currently the subject of active research. The complementarity of quantum coherence in different bases was studied by deriving upper bounds on the sum of the corre- sponding measures. To obtain a two-sided estimate, lower bounds on the coherence quantifiers are also of interest. Such bounds are naturally referred to as uncertainty relations for quantum coherence. We obtain new uncertainty relations for coherence quantifiers averaged with respect to a set of mutually unbiased bases （MUBs）. To quantify the degree of coherence, the relative entropy of coherence and the geometric coherence are used. Further, we also derive novel state-independent uncertainty relations for a set of MUBs in terms of the min-entropy.

关键词： coherence complementarity uncertainty mutually unbiased bases

Generalized Conditional entropies of Partitions on Quantum Logic

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Communications in Theoretical Physics 2012年第12期58卷 819-822页

作者： alexey e. rastegin Department of Theoretical Physics Irkutsk State University

For partitions on quantum logic, the Rdnyi and Tsallis conditional entropies are introduced. Several relations between the conditional entropies of such partitions are derived.

关键词： quantum logic Renyi entropy Tsallis entropy

Decline and fall of aging astrocytes:the human perspective

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Neural Regeneration Research 2025年第6期20卷 1713-1714页

作者： Alexei Verkhratsky alexey Semyanov Faculty of Biology Medicine and HealthThe University of ManchesterManchesterUK Department of Neurosciences University of the Basque Country UPV/EHU and CIBERNEDLeioaSpain Department of Forensic Analytical Toxicology School of Forensic MedicineChina Medical UniversityShenyangLiaoning ProvinceChina Department of Stem Cell Biology State Research Institute Centre for Innovative MedicineVilniusLithuania International Collaborative Center on Big Science Plan for Purinergic Signalling Chengdu University of Traditional Chinese MedicineChengduSichuan ProvinceChina Department of Physiology Jiaxing University College of MedicineJiaxingZhejiang ProvinceChina

“Last scene of all that ends this strange,eventful history,is second childishness and mere oblivion.I am sans teeth,sans eyes,sans taste,sans everything.”William Shakespeare‘As You Like It'Act 2,Sc.7,l.139Aging of the human brain is characterized by a progressive decline of its functional capacity;this decline however varies widely,and cognitive longevity differs substantially between individuals.

关键词： aging teeth progressive

On Splitting of the Normalizer of a Maximal Torus in e6(q)

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Algebra Colloquium 2019年第2期26卷 329-350页

作者： alexey Galt alexey Staroletov Sobolev Institute of Mathematics Novosibirsk Russia

Let G be a finite group of Lie type e6 over Fq (adjoint or simply connected) and W be the Weyl group of G. We describe maximal tori T such that T has a complement in its algebraic normalizer N(G, T). It is well known that for each maximal torus T of G there exists an element w ∈ W such that N(G, T )/T ■ CW(w). When T does not have a complement isomorphic to CW(w), we show that w has a lift in N(G, T) of the same order.

关键词： finite group of Lie type maximal torus algebraic normalizer split extension

Normal forms of linear second order partial differential equations on the plane

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Science China Mathematics 2018年第11期61卷 1947-1962页

作者： alexey Davydov Department of Mathematics The National University of Science and Technology MISiS Moscow 119049 Russia Department of Theory of Dynamical Systems Lomonosov Moscow State University Moscow 119991 Russia International Institute for Applied Systems Analysis Laxenburg A-2361 Austria

The paper is devoted to the theory of normal forms of main symbols for linear second order partial differential equations on the *** discuss the results obtained in the last decades and some problems,which are important both for the development of this theory and the *** reduction theorem,which was used to obtain many of recent results in the theory,is included in the paper in the parametric form together with *** is a feeling that the theorem still has potential to get progress in the solution of open problems in the theory.

关键词： normal form mixed type partial differential equation main symbol

Shock-wave impact on the knee joint affected with osteoarthritis and after arthroplasty

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Defence Technology（防务技术） 2023年第2期20卷 1-10页

作者： Galina eremina alexey Smolin Institute of Strength Physics and Materials Science of Siberian Branch of Russian Academy of Sciences 2/4pr.AkademicheskiiTomsk634055Russia

Degenerative diseases significantly reduce the quality of human ***-invasive treatments are used in the initial stages of osteoarthritis(OA).Total knee arthroplasty is used in the late stages of osteoarthritis of the knee ***-invasive methods based on mechanical action are also used for the rehabilitation of a patient after *** paper presents numerical models of the knee joint with degenerative OA changes and *** these models,a computational study was made of the influence of the intensity of shock-wave exposure on the conditioning for the regeneration of bone and cartilage *** on the modeling results,it was found that in the knee joint with degenerative OA changes,conditions for the regeneration of cartilage and meniscus tissues were fulfilled under medium and highintensity *** high-intensity loading(up to 0.9 m J/mm^(2)),the stress level was significantly below the ultimate value required for *** knee arthroplasty,the conditions for bone tissue regeneration around the tibia component are fulfilled only under high-intensity loading.

关键词： Knee joint Total knee replacement Shock-wave therapy Computer simulation Method of movable cellular automata