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Asymptotics of eigenfunctions of perturbed resonance oscillator near upper boundaries of spectral clusters
Journal of Mathematical Sciences. 2025. Vol. 291. No. 4. P. 544–553.
We study the eigenvalue problem for a perturbed resonance oscillator. We find asymptotic
expansions of coherent states of the algebra su(2). We show that the asymptotic
eigenfunctions are localized near a circle and construct an expansion of asymptotic eigenfunctions
near this circle.
Aleksei Samarin, Nazarenko A., Nazarenko D. et al., Machine Learning and Knowledge Extraction 2026 Vol. 8 No. 10 Article 330
Automated microscopic image analysis is essential for quantitative microbiology, yet manual acquisition and generic recognition models struggle with morphological variability and scene artifacts. We address both ends of this pipeline. First, we present a low-cost, open-source acquisition system, based on an Arduino UNO R3 microcontroller and NEMA 17 stepper motors, that automates focusing, magnification, and ...
Added: October 14, 2026
Parkhomenko V., Kulikova S., Buzmakov A. V., Lobachevskii Journal of Mathematics 2026 Vol. 47 No. 6 P. 2979–2992
The stability of formal concepts and its generalization as robustness are considered in the paper. We use an approximation of stability in the form of Δ-measure for fast calculations. A computationally efficient method for calculating robustness based on subcontexts is presented. We also present a new method to analytically evaluate the number of preimages for ...
Added: October 14, 2026
Kuznetsov A. P., Sedova Y. V., Sataev I. R. et al., Mathematics and Computers in Simulation 2027 Vol. 2 P. 574–592
Universal bifurcation structures on the parameter plane of nonlinear systems, known as shrimps, are discussed. An overview of numerous examples from various fields of science is given. Shrimps are typical for both maps of different dimensions and flows. The varieties of shrimp are discussed and relevant examples are given. The similarity property on the parameter ...
Added: October 14, 2026
Dmitriev A., Kornilov V., Batienkov R., Lecture Notes in Civil Engineering 2026 Vol. 886 P. 249–255
Numerous studies have provided compelling evidence that the probability distribution of avalanche sizes follows a power law, and that 1/f noise is present in the stochastic dynamics of landslides. We present a theoretical explanation of these phenomena within the framework of self-organized criticality theory, proposing a discrete-time model in the form of a sandpile cellular ...
Added: October 13, 2026
Dmitriev A., Shulman I., Lebedev A., Studies in Computational Intelligence 2026 Vol. 1265 P. 266–273
A discrete-time model is presented for the self-organization of the X/Twitter social network to the edge of a phase transition, characterized by avalanche-like propagation of information in the network. The model is based on the analogy between the critical dynamics of the X social network and sandpile cellular automata with Manna rule on the Chung-Lu ...
Added: October 13, 2026
Arutyunov K., Kharitonov I. A., Petrosyants K. O., JETP Letters 2026 Vol. 124 No. 6 P. 1–16
Superconducting properties of metallic micro- and nanowires can be entirely different from those of bulk superconductors. Of particular interest is the nonequilibrium current-induced state of a quasi-one-dimensional superconducting channel. The most interesting phenomenon here is the stepped I–V characteristic, explained by a process known as phase slip center activation. If the origin of such step-like ...
Added: October 13, 2026
Makarov D. M., Kalikin N., Fashchevsky K. A. et al., Electrochimica Acta 2026 Vol. 579 Article 150159
Machine learning (ML) has become a powerful tool for accelerating the development of carbon-based supercapacitors;
however, most published models assume that a single predictive framework can describe both conventional
porous carbons and hybrid carbon electrodes. Here, we test this assumption using a comprehensive
benchmark dataset and an extended literature-curated dataset enriched with synthesis- and electrolyte-related
descriptors. Three ML algorithms ...
Added: October 13, 2026
Gusein-Zade S., Campillo A., Delgado F., Mathematische Zeitschrift 2026 Vol. 314 No. 1 P. 1–22
For a subfield $\K$ of the field $\C$ of complex numbers, we consider curve and divisorial valuations on the algebra $\K[[x,y]]$ of formal power series in two variables with the coefficients in $\K$. We compute the semigroup Poincar\'e series and the classical Poincar\'e series of a (discrete, rank one) valuation on it. ...
Added: October 13, 2026
Махлуф М., Ozhegov R., Elezov M. et al., Фотоника 2026 Vol. 20 No. 6 P. 414–423
This paper compares the ranging precision of direct time-of-flight (dToF) and non-line-of-sight (NLOS) LiDAR architectures, both using a superconducting nanowire single-photon detector (SNSPD). Both systems operate at 1550 nm with a 50 ps pulsed laser and time-correlated single-photon counting (TCSPC). The dToF configuration achieved approximately 100 µm precision at 10 m, while the NLOS configuration achieved 500 µm precision for ...
Added: October 12, 2026
A. V. Pereskokov, Journal of Mathematical Sciences 2026 Vol. 302 No. 4 P. 531–545
We consider the Zeeman effect problem for the hydrogen atom in a magnetic field using
irreducible representations of the Karasev–Novikova algebra with quadratic commutation
relations. We find the asymptotics of a series of eigenvalues and the corresponding
asymptotic eigenfunctions near the upper boundaries of spectral clusters. ...
Added: October 1, 2026
Об асимптотических собственных значениях оператора типа Хартри вблизи границ спектральных кластеров.
А.В. Перескоков, В кн.: Современные методы теории краевых задач. Понтрягинские чтения XXXVII.: Воронеж: Издательский дом ВГУ, 2026. С. 251–252.
Рассматривается задача на собственные значения для возмущенного двумерного осциллятора. В качестве возмущения выступает интегральная нелинейность типа Хартри, потенциал самодействия в которой зависит от расстояния между точками и имеет одновременно кулоновскую и логарифмическую особенность. Найдены асимптотические собственные значения и асимптотические собственные функции вблизи границ спектральных кластеров, которые образуются около собственных значений невозмущенного оператора. Доказана новая формула ...
Added: June 25, 2026
А.В. Перескоков, В кн.: Воронежская зимняя матаматическая школа С. Г. Крейна - 2026.: Воронеж: Издательский дом ВГУ, 2026. С. 237–239.
Рассмотрена задача на собственные значения
для возмущенного резонансного осциллятора. Найдены
асимптотические разложения когерентных состояний алгебры вращений.
Показано, что асимптотические собственные функции локализованы вблизи окружности.
Построено разложение асимптотических собственных функций вблизи этой окружности. ...
Added: June 25, 2026
A. V. Pereskokov, Theoretical and Mathematical Physics 2026 Vol. 226 No. 3 P. 470–484
We consider the spectral problem for a hydrogen atom in orthogonal electric and magnetic fields with
an additional self-consistent field. We obtain an asymptotic expansion of self-consistent energy levels.
We find an asymptotic expansion of asymptotic eigenfunctions near the sphere |q| = 2. We calculate the
asymptotics of their norm in the space L2(R3). ...
Added: April 12, 2026
Перескоков А.В., В кн.: Сборник тезисов международной конференции "Дифференциальные уравнения и смежные вопросы", 25-е совместное заседание Московского математического общества и Семинара имени И.Г.Петровского Москва, 19– 24 мая 2025.: MSU Pub, 2025. С. 236–238.
Рассмотрена спектральная задача для атома водорода в магнитном поле, возмущенном самосогласованным полем. Получено асимптотическое разложение самосогласованных уровней энергии. ...
Added: June 15, 2025
А.В. Перескоков, В кн.: Современные методы теории функций и смежные проблемы.: Издательский дом ВГУ, 2025. С. 267–268.
Найдены асимптотические собственные значения для нелинейного
оператора типа Хартри в случае, когда потенциал самодействия является разностью
кулоновского и экранированного кулоновского потенциалов. ...
Added: May 9, 2025
A. V. Pereskokov, Theoretical and Mathematical Physics 2025 Vol. 222 No. 3 P. 453–470
The spectral problem for the hydrogen atom in a magnetic field perturbed by a self-consistent field is
considered. An asymptotic expansion of self-consistent energy levels is obtained. An asymptotic expansion
of hypergeometric coherent states near the sphere |q| = 2 is found. The asymptotics of the norm of the
asymptotic eigenfunctions in the space L2(R3) is calculated. ...
Added: April 24, 2025
Vybornyi E., Rumiantseva S., Математические заметки 2024 Т. 116 № 6 С. 862–880
In this paper, we consider the problem of constructing a semiclassical asymptotic estimate of the splitting between a pair of close lower-lying energy levels for a quadratic operator defined on the irreducible representation of the Lie algebra su(1,1). In Darboux coordinates on the hyperboloid the Hamiltonian defines the landscape of a symmetric double well. It ...
Added: November 12, 2024
Sofia V. Rumyantseva, Acta Applicandae Mathematicae 2025 Vol. 195 Article 4
Difference equations play a crucial role in a wide array of mathematical and physical tasks. In this article, we focus on the analysis of a second order linear homogeneous difference equation with smooth coefficients via WKB method. It is well-known that such equations exhibit two WKB solutions in a segment devoid of turning and singular ...
Added: November 2, 2024
A. V. Pereskokov, Journal of Mathematical Sciences 2024 Vol. 281 No. 4 P. 612–624
We consider the eigenproblem for a Hartree type operator with a small parameter at
nonlineratiry, where the self-action potential is the difference between the Coulomb potential
and the screened Coulomb potential. We find asymptotic eigenvalues and asymptotic
eigenfunctions near the upper boundaries of spectral clusters which appear near the
energy levels of an unperturbed operator. ...
Added: June 1, 2024
А.В. Перескоков, В кн.: Воронежская зимняя математическая школа С. Г. Крейна – 2024 : материалы международной Воронежской зимней математической школы, посвященной памяти В. П. Маслова (26–30 января 2024 г.).: Воронеж: Издательский дом ВГУ, 2024. С. 195–197.
Рассмотрена задача на собственные значения для оператора Хартри
с малым параметром перед нелинейностью. Найдены асимптотические собственные значения и
асимптотические собственные функции, локализованные вблизи сферы. Получены асимптотические разложения самосогласованного потенциала. ...
Added: May 3, 2024
А.В. Перескоков, В кн.: Современные методы теории краевых задач. Понтрягинские чтения - XXXIV.: Воронеж: Издательский дом ВГУ, 2023. С. 302–304.
В данной работе найдены асимптотические собственные значения и асимптотические собственные функции атома водорода в электромагнитном поле вблизи нижних границ спектральных кластеров. ...
Added: December 15, 2023