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On structural proof theory of the modal logic K+ extended with infinitary derivations
We consider an extension of the modal logic of transitive closure K+ with some inifinitary derivations and present a sequent calculus for this extension, which allows non-well-founded proofs. For the given calculus, we obtain the cut-elimination theorem following the lines of so called continuous cut elimination. Our consideration also covers ordinary proofs of K+ since they correspond to cyclic cut-free proofs of the presented sequent calculus.
Priority areas:
mathematics
Language:
English
Селянин Ф. И., Journal of Dynamical and Control Systems 2026 Vol. 32 No. 2 P. 1–16
A B-facet is a lattice -dimensional polytope in the positive octant with a positive normal covector, such that every -dimensional simplex with vertices in it is a B-simplex (i.e., a pyramid of height one with base on a coordinate hyperplane). B-facets were introduced in [2] in the context of the monodromy conjecture. In this paper, we complete the ...
Added: May 21, 2026
Kildyushov O., Мир России: Социология, этнология 2026 Т. 35 № 2 С. 6–21
This article examines a heuristic framework for analyzing the significance of Russian themes in Max Weber’s corpus, in connection with the completion of the complete edition of his works as a comprehensive source base. It highlights the ambivalent position of Russian themes in the his legacy: while Russia was never central to his scholarship, the issue ...
Added: May 20, 2026
Поликарпова Д. А., М.: Новое литературное обозрение, 2025.
Может ли кино быть субъектом, а не объектом особой чувственности? В своей книге Дарина Поликарпова утверждает, что да; более того, идея эта не нова и восходит к опытам Дзиги Вертова, Жана Эпштейна и других ранних практиков и теоретиков кино. Увлекшееся в последние десятилетия антропоцентрическими подходами, киноведение перестало учитывать уникальную природу кинематографа, сводя его к тексту, ...
Added: May 19, 2026
Denis Seliutskii, Russian Journal of Mathematical Physics 2025 Vol. 32 No. 2 P. 399–407
In this paper, we find an upper bound for the first Steklov eigenvalue for a surface of revolution with boundary consisting of two spheres of different radii. Moreover, we prove that, in some cases, this boundary is sharp. ...
Added: May 19, 2026
Пильнов И. А., История философии 2024 Т. 29 № 2 С. 39–50
This article attempts a comparative analysis of the problems of revolution and socialism in the philosophical work of Nikolai Berdyaev and Boris Yakovenko. The author aims to compare the key philosophical and political concepts of the two thinkers to identify the commonalities and differences in their views. The subject of consideration are the works of ...
Added: May 18, 2026
Жакупов О. Б., European Journal of Mathematics 2025 Vol. 11 Article 84
We provide examples of smooth three-dimensional Fano complete intersections of degree 2, 4, 6, and 8 that have absolute coregularity 0. Considering the main theorem of Avilov, Loginov, and Przyjalkowski (CNTP 18:506–577, 2024) on the remaining 101 families of smooth Fano threefolds, our result implies that each family of smooth Fano threefolds has an element of absolute ...
Added: May 18, 2026
Bobrova A., Poddiakov A., Aksiotis V., Вопросы психологии 2025 № 4 С. 96–106
In psychology, people's assessment of conditional statements "if--then", agreement and disagreement with them is actively studied. This assessment of people who are not specialists in the field of logic often differs greatly from its requirements, especially if the reality observed by a person to one degree or another contradicts a formally correct logical conclusion. In ...
Added: May 17, 2026
Mamchenkov D. V., Malyutina, AD (Malyutina, Anna D.), Studia Philosophica Kantiana 2022 No. 1 P. 45–55
The article examines various historical and philosophical premises
of radical constructivism. The three most appropriate philosophical concepts
for this role are: ancient skepticism, subjective idealism, and Kantian transcendental
idealism. It is shown that radical constructivism cannot be attributed
to ancient skepticism or subjective idealism. It is transcendental idealism
that should be considered as the main forerunner of this concept. The ...
Added: May 17, 2026
Girinsky A., Вестник Томского государственного университета 2026 № 525 С. 67–73
В данной статье анализируются работы православного богослова и религиозного публициста прот. А. Шмемана, посвященные проблеме секуляризации в обществе модерна. Реконструируется контекст рассуждений Шмемана, связанный с развитием в послевоенное время в США и Европе идей теории модернизации и «секулярной теологии». Отмечается оригинальность трактовки Шмеманом сущности секуляризации как элиминации «сакраментальности богослужения», критически анализируются выводы Шмемана, связанные с ...
Added: May 16, 2026
Gonchenko S., Lerman L., Turaev D., Regular and Chaotic Dynamics 2026 Vol. 31 No. 3 P. 349–369
We show that bifurcations of four-dimensional symplectic diffeomorphisms with a quadratic homoclinic tangency to a saddle periodic orbit with real multipliers produce 2-elliptic periodic orbits if the tangency is not partially hyperbolic. We show that a normal form for the rescaled first-return maps near such tangency is given by a four-dimensional symplectic H´enonlike map and study bifurcations of the ...
Added: May 15, 2026
Aleskerov F. T., Khutorskaya O., Stepochkina A. et al., Springer, 2026.
The book contains new models of bibliometric analysis based on centrality measures in network analysis, pattern analysis and stability analysis. A distinctive feature of these centrality measures is that they account for the parameters of vertices and group influence of vertices to a vertex. This reveals specific groups of publications, authors, terms, journals and affiliations ...
Added: May 15, 2026
Kuptsov P., Panyushev A., Stankevich N., Chaos 2026 Vol. 36 No. 5 Article 053138
We develop a machine-learning approach to reproduce the behavior of two versions of the van der Pol oscillator exhibiting a subcritical Andronov–Hopf bifurcation, with or without a codimension-2 Bautin point. We construct a neural-network model that functions as a recur rent map and train it on short segments of oscillator trajectories. The results show that, ...
Added: May 15, 2026
Dorovskiy A., / Series arXiv "math". 2026.
In this paper the structural stability of generic families of vector fields of the PC-HC class on the two-dimensional sphere is proved. A classification of these families up to moderate equivalence in neighborhoods of their large bifurcation supports is presented, based on such invariants as the configuration and the characteristic set. The realization lemma is proved. ...
Added: May 14, 2026
Morozov D., Вестник Православного Свято-Тихоновского гуманитарного университета. Серия 1: Богословие. Философия. Религиоведение 2026 № 124 С. 45–58
The article analyzes the concept of “aesthetic humanism” (AH) presented in the works of V. V. Zenkovsky. Within his original conception, AH is regarded as the fundamental principle of Russian secularism. The article focuses on Zenkovky’s historical-philosophical dialectic, the key to which is the overcoming of AH — a “spiritual malady” of Western origin that ...
Added: May 14, 2026
Taletskii D., / Series arXiv "math". 2026.
A vertex subset of a graph is called a \textit{distance-$k$ independent set} if the distance between any two of its distinct vertices is at least $k + 1$. For all $n,k \geq 1$, we determine the minimum possible number of inclusion-wise maximal distance-$k$ independent sets among all $n$-vertex trees. It equals~$n$ if $n \leq k ...
Added: May 1, 2026
Ovcharenko M., / Series arXiv "math". 2026.
We introduce an explicit class of tempered Laurent polynomials in the sense of Villegas and Doran--Kerr in n⩽4 variables including all Landau--Ginzburg models for smooth Fano threefolds with very ample anticanonical class. We check that it contains Landau--Ginzburg models for various Fano fourfolds which are complete intersections in smooth toric varieties and Grassmannians of planes, ...
Added: April 30, 2026
Zlotnik Alexander, / Series arXiv "math". 2026. No. 2602.03481v1.
We deal with the global in time weak solutions to the 1D compressible Navier-Stokes system of equations for large discontinuous initial data and nonhomogeneous boundary conditions of three standard types. We prove the Lipschitz-type continuous dependence of the solution $(\eta,u,\theta)$, in a norm slightly stronger than $L^{2,\infty}(Q)\times L^2(Q)\times L^2(Q)$, on the initial data $(\eta^0,u^0,e^0)$ in a ...
Added: April 18, 2026
Medvedev V., / Series arXiv "math". 2026.
We investigate the interplay between the dimension of the space of static potentials and the geometric and topological structure of the underlying static three-manifold. A partial classification of boundaryless static manifolds is obtained in terms of this dimension. We also treat the case of static manifolds with boundary. In particular, we prove that if a ...
Added: April 3, 2026
Gabdullin N., Androsov I., / Series Computer Science "arxiv.org". 2026.
Label prediction in neural networks (NNs) has O(n) complexity proportional to the number of classes. This holds true for classification using fully connected layers and cosine similarity with some set of class prototypes. In this paper we show that if NN latent space (LS) geometry is known and possesses specific properties, label prediction complexity can ...
Added: April 2, 2026
Kolesnikov A., / Series arXiv "math". 2025.
We study Blaschke--Santal{ó}-type inequalities for N>=2 sets (functions) and a special class of cost functions. In particular, we prove new results about reduction of the maximization problem for the Blaschke--Santal{ó}-type functional to homogeneous case (functional inequalities on the sphere) and extend the symmetrization argument to the case of N>2 sets.
We also discuss links to the ...
Added: February 13, 2026
Sorokin K., Beketov M., Онучин А. et al., / arxiv.org. Серия cs.SI "Social and Information Networks ". 2025.
Community detection in complex networks is a fundamental problem, open to new approaches in various scientific settings. We introduce a novel community detection method, based on Ricci flow on graphs. Our technique iteratively updates edge weights (their metric lengths) according to their (combinatorial) Foster version of Ricci curvature computed from effective resistance distance between the ...
Added: January 15, 2026
Gaianov N., Parusnikova A., / Cornell University. Серия math "arxiv.org". 2025.
An algebraic q-difference equation is considered. A sufficient condition for the existence of a formal power-logarithmic expansion of a solution to such an equation in the neighborhood of zero is proposed. An example of applying this sufficient condition for constructing a formal expansion of a solution to a certain q-difference analogue of the fifth Painlevé equation ...
Added: December 25, 2025
Popov V., / Series arXiv "math". 2025. No. 2502.01539.
We prove that the variety of flexes of algebraic curves
of degree 3 in the projective plane is an ideal theoretic complete
intersection in the product of a two-dimensional and a nine-dimensional projective spaces. ...
Added: December 16, 2025
Gnetov F., Konakov V., / Series arXiv "math". 2025. No. 2512.04667.
We establish a central limit theorem, a local limit theorem, and a law of large numbers for a natural
random walk on a symmetric space M of non-compact type and rank one. This class of spaces, which
includes the complex and quaternionic hyperbolic spaces and the Cayley hyperbolic plane, generalizes
the real hyperbolic space Hn. Our approach introduces ...
Added: December 5, 2025