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Existence Theorem for Coverings of Serre Bundles
Russian Mathematics, USA. 2023. Vol. 67. No. 3. P. 76–84.
In this paper, we study coverings of the Serre bundle category. A covering mapping of one such bundle onto another is understood as a morphism of the indicated category that consists of covering mappings of total spaces and bases. Earlier, the author associated each such covering with a subsequence of the homotopy sequence of the base bundle. The conjugacy class of this subsequence was also shown to be an invariant of the corresponding covering. The main result of this study is the existence theorem for a covering with a specified invariant. The local triviality of the base bundle is proved here to imply a similar property for the covering bundle.
Publication based on the results of:
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 ...
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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 ...
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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. ...
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Mishuris G., Meylan M. H., Pelinovsky E., Journal of Fluid Mechanics 2026 Vol. 1045 Article A4
In this paper, we revisit the classic problem of a wave field on a sloping beach of an arbitrary angle and propose a general approach that allows the computation of regular solutions of the problem regardless of the angle. We use the Mellin-transform technique, reducing the problem to singular integral equations with fixed-point singularities of ...
Added: October 12, 2026
Gusein-Zade S., М.: МЦНМО, 2026.
Книга содержит курс лекций по дифференциальной геометрии и топологии, читавшихся автором на механико-математическом факультете МГУ в разные годы. В дополнениях приводятся некоторые сюжеты (связности в расслоениях, теорема Фробениуса, производные Ли и др.), которые были включены в курс в отдельные годы либо содержались в аналогичных курсах лекций в Независимом московском университете.
Для студентов математических и физических специальностей. ...
Added: October 12, 2026
Брычков М. Е., Незнанов А.А., Программирование 2026 № 4 С. 50–66
The matrix profile (MP) quickly became one of the most important time series preprocessing methods when it was introduced in 2016, facilitating the solution of a wide range of time series analysis problems, in particular anomaly and pattern detection problems. The high significance has led to the emergence of various tools for MP calculating, but ...
Added: October 9, 2026
М.: Юрайт, 2026.
The Collection of Olympiad Problems (COP) in Probability Theory and Mathematical Statistics (PTMS) is offered as a teaching aid primarily for university students and faculty as a developmental supplementary resource, expanding the range of problems to be solved in lectures, seminars, and out-of-class independent work with students in various formats, including (as the title suggests) ...
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Aleskerov F. T., Вайншток А. П., Делахова А. М. et al., Информационные процессы 2026 Т. 26 № 3 С. 895–913
The development and effective management of territorial entities are priority issues for all states, particularly in the context of the digital transformation of public administration. Over the past decade, the integration of information technologies into municipal and regional planning has significantly altered approaches to strategic development, service delivery, and public engagement. This paper describes the ...
Added: October 9, 2026
Kupavskii A., Noskov F., Forum of Mathematics, Sigma 2026 Vol. 14 Article 124
We call a family of $s$ sets $\{F_1, \ldots, F_s\}$ a sunflower with $s$ petals if, for any distinct $i, j \in [s]$, one has $F_i \cap F_j = \cap_{u = 1}^s F_u$. The set $C = \cap_{u = 1}^s F_u$ is called the {\it core} of the sunflower. It is a classical result of ...
Added: October 8, 2026
Flamarion M. V., Pelinovsky E., Chaos, Solitons and Fractals 2026 Vol. 213 No. 2 Article 119245
This article concerns the study of modulational instability in the rotated-modified Gardner–Whitham (rmGW) equation. This model incorporates both quadratic and cubic nonlinearities, similarly to the Gardner equation, while also retaining the fully dispersive character of the Whitham equation together with a large-scale dispersive term analogous to that in the Ostrovsky equation. Using a classical multiple-scale asymptotic expansion, we ...
Added: October 8, 2026
Люксембург А. А., УРСС, 2005.
Изучается возможность автоматизированного построения математических теорий. Рассматривается дедуктивная система, основанная на языке логики предикатов первого порядка, объектами системы являются математические выражения или формулы, которые описывают математические объекты или их свойства. В дедуктивной системе выводятся математические определения и теоремы. Для доказательства теорем используются методы автоматического доказательства. Разработан алгоритм, выводящий часть формул системы. Для решения задачи используется аппарат математической ...
Added: October 7, 2026
Aleskerov F. T., Chaika E., Дерендяев А. Б. et al., Procedia Computer Science 2026 No. 287 P. 590–595
Under conditions of dynamic socio-economic changes, effective planning and decision-making are key factors in ensuring a high quality of life for the population in territories. This paper presents a decision support system for territorial administrations for the development and implementation of sustainable development strategies, using one of the regions of the Russian Federation – the ...
Added: October 7, 2026
Bernardin C., Gonçalves P., Olla S., Mathematical Physics Analysis and Geometry 2024 Vol. 27 No. 7
We consider the macroscopic limit for the space-time density fluctuations in the open symmetric simple exclusion in the quasi-static scaling limit. We prove that the distribution of these fluctuations converge to a gaussian space-time field that is delta correlated in time but with long-range correlations in space. ...
Added: October 6, 2026
Bernardin C., Chhaibi R., Najnudel J. et al., Probability Theory and Related Fields 2026 Vol. 195 P. 1823–1875
We study the celebrated Shiryaev-Wonham filter (Wonham, W.M., in J. Soc. Ind. Appl. Math. 347–369, 1964) in its historical setup, where the hidden Markov jump process has two states. We are interested in the weak noise regime for the observation equation. Interestingly, this becomes a strong noise regime for the filtering equations. Earlier results of ...
Added: October 5, 2026
Ismailov A., Spiridonov V., Успехи математических наук 2026 Т. 81 № 5 С. 183–184
Получена новая формула для цепной дроби Аски–Вильсона в форме отношения двух q-гипер-геометрических рядов. ...
Added: October 5, 2026
Abdulkhaev K., Shirokov D., Advances in Applied Clifford Algebras 2026 Vol. 36 P. 1–21
In this paper, we present explicit formulas for the inverse and determinant in geometric (Clifford) algebras over vector spaces of dimension n = 7. The derivation of these formulas is made possible by generalizing the concept of conjugation to basis conjugation operations. We further develop a general method for constructing such formulas over odd-dimensional spaces ...
Added: October 4, 2026
D. A. Maksimov, Yakovlev E., Lobachevskii Journal of Mathematics 2024 Vol. 45 No. 8 P. 3924–3934
Regular coverings of Lorentzian manifolds are studied under the assumption that the covering map is isometric and preserves time orientation. Conditions for the covering manifold are obtained that are necessary and sufficient for the base to be chronological, causal, strongly or stable causal, and also globally hyperbolic manifold. As a corollary, statements are obtained that ...
Added: November 23, 2024
Е. И. Яковлев, В кн.: Труды Математического центра имени Н.И. Лобачевского. Том 62.: КФУ, 2022. С. 125–127.
Исследуются накрытия в категории расслоений Серра. Под накрывающим отображением одного расслоения на другое понимается морфизм указанной категории, состоящий из накрывающих отображений тотальных пространств и баз. Построены инварианты таких накрытий и доказана теорема существования накрытия с заданным инвариантом. Показано, что из локальной тривиальности базового расслоения следует аналогичное свойство для накрывающего расслоения. ...
Added: October 24, 2022
Yakovlev E., Russian Mathematics (USA) 2022 № 3 С. 71–84
The category of coverings of a given Serre bundle is investigated. By a covering mapping
of one such bundle onto another we mean a morphism in the category of bundles consisting of
covering mappings of total spaces and bases. An invariant of a covering from the indicated category
is constructed, which is the conjugacy class of some subsequence ...
Added: August 10, 2022
Yakovlev E., В кн.: Материалы Международной конференции по алгебре, анализу и геометрии 2021.: Каз.: Издательство Академии наук Республики Татарстан, 2021. С. 418–421.
Added: September 21, 2021
Gonchar T., Yakovlev E., Russian Mathematics 2021 Vol. 65 No. 4 P. 22–43
Исследуется категория регулярных накрытий заданного гладкого главного расслоения. Под накрывающим отображением одного главного расслоения на другое понимается морфизм в категории главных расслоений, состоящий из накрывающих отображений структурных групп, тотальных пространств и баз. Основные результаты: построение инварианта регулярного накрытия, представляющего собой подпоследовательность гомотопической последовательности базового расслоения, теорема существования накрытия с заданным инвариантом, критерии морфизмов и изоморфизмов, ...
Added: September 21, 2021
А.А. Ерискин, В кн.: VI Всероссийская молодежная конференция по фундаментальным и инновационным вопросам современной физики.: М.: РИИС ФИАН, 2015. С. 113–113.
The possibility of applying protective coatings on the inner surface of the thin Cu-tubes on devices such as plasma focus. The coatings obtained by the erosion of the anode material (Cu, W) with a plasma pulse. It is found that the coating composition is a complex material comprising: Cu, O, C, W, Fe, Ni. The ...
Added: November 25, 2015
Smirnov A., Matveenko S., Semenova E., Symmetry, Integrability and Geometry: Methods and Applications (SIGMA) 2015 Vol. 11
In the article, we describe three-phase finite-gap solutions of the focusing nonlinear Schrödinger equation and Kadomtsev-Petviashvili and Hirota equations that exhibit the behavior of almost-periodic ''freak waves''. We also study the dependency of the solution parameters on the spectral curves. ...
Added: October 15, 2015