Kh. Kh. Abdullin, D. B. Mokeev, D. S. Taletskii, Mathematical notes 2026 Vol. 119 No. 1 P. 3–7
By the Ramsey number R(K1,s,Pt) one means the least positive integer n such that, for every n-vertex graph G, the following condition holds: either G contains a vertex of degree at least s or the complement of G contains a simple t-path. In this paper, we fi nd precise values of R(K1,s,Pt) for certain values ...
Added: June 10, 2026
Springer, 2026.
The book presents the proceedings of the 13th International Conference on Frontiers of Intelligent Computing: Theory and Applications (FICTA 2024), held at Intelligent Systems Research Group (ISRG), London Metropolitan University, London, United Kingdom, during June 6–7, 2025. Researchers, scientists, engineers and practitioners exchange new ideas and experiences in the domain of intelligent computing theories with ...
Added: June 8, 2026
Flamarion M. V., Pelinovsky E., Nonlinear Dynamics 2026 Vol. 114 Article 784
In this article, we investigate wave packet and solitary wave dynamics in the Whitham–Ostrovsky (WO) equation. By means of a multiple-scales expansion, we formally derive a nonlinear Schrödinger (NLS) equation governing the envelope evolution.The corresponding modulational stability diagram is then obtained using the Lighthill criterion. We show that sufficiently large values of the low-frequency dispersive term render ...
Added: June 5, 2026
Medvedev T. V., Pochinka O., Chaos 2026 Vol. 36 No. 6 Article 063107
We consider 3-diffeomorphisms with source–sink dynamics where Smale solenoids play the role of the source and the sink (NSSS-diffeomorphisms). It is known that such diffeomorphisms exist only on lens spaces. On the 3-sphere, every NSSS-diffeomorphism is associated with an exchangeable braid. An exchangeable braid with the strand number n was constructed for each n 3 in such a way ...
Added: June 4, 2026
Kazakov A., Mints D., Petrova I. et al., Chaos 2026 Vol. 36 No. 6 Article 063112
We study hyperbolic chaotic dynamics for maps of a two-dimensional torus. We introduce a two-parameter family of diffeomorphisms which, as we show, demonstrates all types of hyperbolic chaotic dynamics that can appear in the two-dimensional case. In addition, we describe all the bifurcations responsible for the transitions between these chaotic regimes. ...
Added: June 4, 2026
Nozdrinova E., Pochinka O., Shmukler V., Математический сборник 2026 Т. 217 № 6 С. 71–89
Гомеоморфизмы топологических пространств называются эквивалентными по надстройке, если надстройки над ними топологически эквивалентны. В частности, топологически сопряженные гомеоморфизмы эквивалентны по надстройке. Известно, что для гомологически неприводимых гомеоморфизмов их топологическая сопряженность является необходимым и достаточным условием их эквивалентности по надстройке. Тогда как инварианты топологической сопряженности гомологически приводимых гомеоморфизмов во многих случаях являются избыточными для эквивалентности по ...
Added: June 3, 2026
Gnetov F., Konakov V., Успехи математических наук 2026 Т. 81 № 3 (489) С. 161–162
Пусть M обозначает симметрическое пространство некомпактного типа ранга 1. Опираясь на фундаментальную работу [1], в [2] было показано, что плотность соответствующим образом нормированной суммы независимых Hn-значных случайных величин, определенная через сложение Мёбиуса в модели шара Пуанкаре, сходится к фундаментальному решению соответствующего уравнения теплопроводности. Пределом являлся нормальный закон на Hn, соответствующий ядру теплопроводности, определяемому оператором Лапласа–Бельтрами. ...
Added: June 2, 2026
Gorbounov Vassily, Kazakov A., Data Analytics and Topology 2025 Vol. 1 No. 1 P. 33–45
A classic problem in data analysis is studying the systems of subsets defined by either a similarity or a dissimilarity function on X which is either observed directly or derived from a data set.
For an electrical network there are two functions on the set of the nodes defined by the resistance matrix and the response ...
Added: May 28, 2026
Gurevich D., Saponov P. A., International Mathematics Research Notices 2025 Vol. 2025 No. 3 Article rnae288
We establish a q-version of the Schur–Weyl duality, in which the role of the symmetric group algebra is played by the Hecke algebra and the role of the enveloping algebra U(gl(N)) is played by the reflection equation (RE) algebra, associated with a skew-invertible Hecke symmetry. Also, in each RE algebra we define analogues of the Schur polynomials and ...
Added: January 31, 2025
Gavrilova S., Algebraic Combinatorics 2023 Vol. 6 No. 1 P. 37–51
Fully inhomogeneous spin Hall–Littlewood symmetric rational functions $F_{\lambda}$ are multiparameter deformations of the classical Hall–Littlewood symmetric polynomials and can be viewed as partition functions in 𝔰𝔩(2) higher spin six vertex models.
We obtain a refined Littlewood identity expressing a weighted sum of $F_{\lambda}$’s over all signatures $\lambda$ with even multiplicities as a certain Pfaffian. This Pfaffian can be derived as a partition ...
Added: November 24, 2023
Evgeny Smirnov, Anna Tutubalina, European Journal of Combinatorics 2023 Vol. 107 Article 103613
Schubert polynomials for the classical groups were defined by S.Billey and M.Haiman in 1995; they are polynomial representatives of Schubert classes in a full flag variety over a classical group. We provide a combinatorial description for these polynomials, as well as their double versions, by introducing analogues of pipe dreams, or RC-graphs, for Weyl groups ...
Added: September 14, 2022
Smirnov E., Тутубалина А. А., Математический сборник 2021 Т. 212 № 10 С. 131–151
Subword complexes were defined by A.Knutson and E.Miller in 2004 for describing Gröbner degenerations of matrix Schubert varieties. The facets of such a complex are indexed by pipe dreams, or, equivalently, by the monomials in the corresponding Schubert polynomial. In 2017 S.Assaf and D.Searles defined a basis of slide polynomials, generalizing Stanley symmetric functions, and ...
Added: September 29, 2021
Krasilnikov E., Функциональный анализ и его приложения 2019 Т. 53 № 4 С. 14–26
Недавно С. В. Чмутов, М. Э. Казарян и С. К. Ландо ввели класс инвариантов графов, названных ими теневыми инвариантами (эти инварианты представляют собой градуированные гомоморфизмы из алгебры Хопфа графов в алгебру Хопфа многочленов от бесконечного числа переменных). Они доказали, что результат усреднения почти всякого такого инварианта по всем графам после подходящего перешкалирования переменных превращается в ...
Added: April 16, 2021
Olshanski G., Cuenca C., Moscow Mathematical Journal 2020 Vol. 20 No. 4 P. 645–694
The classical q-hypergeometric orthogonal polynomials are assembled into a hierarchy called the q-Askey scheme. At the top of the hierarchy, there are two closely related families, the Askey–Wilson and q
-Racah polynomials. As it is well known, their construction admits a generalization leading to remarkable orthogonal symmetric polynomials in several variables.
We construct an analogue of the ...
Added: January 19, 2021
Smirnov E., Тутубалина А. А., Успехи математических наук 2020 Т. 75 № 6(456) С. 177–178
В работе рассматривается подразбиение комплексов подслов, определенных Кнутсоном и Миллером, на слайд-комплексы; показано, что эти комплексы являются шеллинговыми и гомеоморфны шару или сфере. ...
Added: October 28, 2020
Smirnov E., Тутубалина А. А., / Series math "arxiv.org". 2020. No. 2009.14120.
Schubert polynomials for the classical groups were defined by S.Billey and M.Haiman in 1995; they are polynomial representatives of Schubert classes in a full flag variety of a classical group. We provide a combinatorial description for these polynomials, as well as their double versions, by introducing analogues of pipe dreams, or RC-graphs, for the Weyl ...
Added: September 30, 2020
Natanzon S., Orlov A. Y., Theoretical and Mathematical Physics 2020 Vol. 204 No. 3 P. 1166–1194
To obtain a generating function of the most general form for Hurwitz numbers with arbitrary base surfaceand arbitrary ramification profiles, we consider a matrix model constructed according to a graph on anoriented connected surfaceΣwith no boundary. The vertices of this graph, called stars, are small discs,and the graph itself is a clean dessin d’enfants. We ...
Added: September 27, 2020
Smirnov E., Тутубалина А. А., / Series math "arxiv.org". 2020. No. 2006.16995.
Subword complexes were defined by A.Knutson and E.Miller in 2004 for describing Gröbner degenerations of matrix Schubert varieties. The facets of such a complex are indexed by pipe dreams, or, equivalently, by the monomials in the corresponding Schubert polynomial. In 2017 S.Assaf and D.Searles defined a basis of slide polynomials, generalizing Stanley symmetric functions, and ...
Added: July 6, 2020
Olshanski G., Journal of Combinatorial Theory, Series A 2019 Vol. 162 P. 65–117
Let Sym denote the algebra of symmetric functions and P_μ( · ; q, t) and Q_μ( · ; q, t) be the Macdonald symmetric functions (recall that they differ by scalar factors only). The (q, t)-Cauchy identity
expresses the fact that the P_μ( · ; q, t)’s form an orthogonal basis in Sym with respect to ...
Added: May 25, 2019
Bychkov B., Михайлов А. В., Успехи математических наук 2019 Т. 74 № 2 С. 189–190
Let $W_G(q_1,q_2,\ldots)$ be a weighted symmetric chromatic polynomial of a graph $G$. S. Chmutov, M. Kazarian and S. Lando in the paper arXiv:1803.09800v2 proved that the generating function $\mathcal{W}(G)$ for the polynomials $W_G(q_1,q_2,\ldots)$ is a $\tau$-function of the Kadomtsev--Petviashvili integrable hierarchy. We proved that the function $\mathcal{W}(G)$ itself is a solution of a linear integrable ...
Added: October 31, 2018
Olshanski G., Borodin A., Cambridge: Cambridge University Press, 2017.
Representation theory of big groups is an important and quickly developing part of modern mathematics, giving rise to a variety of important applications in probability and mathematical physics. This book provides the first concise and self-contained introduction to the theory on the simplest yet very nontrivial example of the infinite symmetric group, focusing on its ...
Added: March 21, 2017