Семинарът по МАТЕМАТИЧЕСКИ ОСНОВИ НА ИНФОРМАТИКАТА организиран от Секция „Математически основи на информатиката“ към ИМИ - БАН и Факултет „Математика и информатика“ - ВТУ, Ви кани на поредната сбирка на 8 януари 2025 г. от 17:00 часа в зала 401 на корпус 4 на ВТУ, на която Prof. Ferruh Özbudak Sabancı University Faculty of Engineering and Natural Sciences, İstanbul - Turkiye ще изнесе доклад на тема: Generalizing the Bierbrauer—Friedman bound to mixed-level orthogonal arrays (joint work with Denis Krotov and Vladimir Potapov) Abstract: We characterize mixed-level orthogonal arrays it terms of algebraic designs in a special multigraph. We prove a mixed-level analog of the Bierbrauer--Friedman (BF) bound for pure-level orthogonal arrays and show that arrays attaining it are radius-1 completely regular codes (equivalently, intriguing sets, [...]

Дата: 14.01.2025 г., 14:00 ч. Място: Зала 403, ИМИ - БАН Докладчик: Jean-Pierre Gazeau от Université Paris-Cité Доклад: Regularized Quantum Motion in a Bounded Set: Hilbertian Aspects Допълнителна информация: https://icms.bg/regularized-quantum-motion-in-a-bounded-set-hilbertian-aspects-talk-by-jean-pierre-gazeau/ Резюме. It is well known that the momentum operator canonically conjugated to the position operator for a particle confined within a bounded interval of the line (with Dirichlet boundary conditions) is not essentially self-adjoint, as it possesses a continuum of self-adjoint extensions. In this talk, we demonstrate that essential self-adjointness can be restored by symmetrically weighting the momentum operator with a positive bounded function that approximates the indicator function of the given interval. This weighted momentum operator arises naturally from a similarly weighted classical momentum through the Weyl-Heisenberg covariant integral quantization of functions or distributions. Reference: [...]

Поредната сбирка на СЕМИНАРА на секция "Математическо моделиране и числен анализ" ще се състои на  30.01.2025 г. (четвъртък) от 14:00 часа по Zoom. Доклад на тема: Some mathematical aspects of simulation modeling of physiological processes in plants ще изнесе Dr. Alex Topaj (Bureau Hyperborea Ltd). Резюме: The contribution presents the author's experience of using mathematical methods to describe plant physiology processes in applied crop models. In contrast to the simplified data-based empirical approach, the mechanistic description of plant vital processes in theory allows us to obtain new knowledge and to develop the universal crop models with parameters having physical meaning. Such explanatory models, in addition to the traditional cause-and-effect method (the flow-balance approach, leading to systems of differential or difference equations), can also successfully apply [...]

Дата: 04.02.2025 г., 14:00 ч. Място: Зала 403, ИМИ - БАН Докладчик: Мирослав Георгиев, Институт по математика и информатика, Българска академия на науките Доклад: Yukawa regulators in electrodynamics: Exact approach to the self-energy and anomalous g-factor Допълнителна информация: https://icms.bg/yukawa-regulators-in-electrodynamics-exact-approach-to-the-self-energy-and-anomalous-g-factor-icms-seminar-talk-by-miroslav-georgiev/ Резюме. In the present talk, we will discuss the prospect of electrodynamics in quantifying the self-interaction of a non-composite charged particle. We will demonstrate that under the consideration of unique to the particle Yukawa cut-offs the radial singularity in corresponding electromagnetic field potentials’ is removed allowing the classical theory to admit exact solutions for the particle’s self-energy and anomalous g-factor. Highly accurate results for the electron’s and muon’s anomalous g-factor will be presented, with calculated values matching the most recent measurements reported in the literature [...]

Дата: 11.02.2025 г., 14:00 ч. Място: Зала 403, ИМИ - БАН Докладчик: Sergey Favorov, Department of Pure Mathematics, Kharkov National University, Ukraine Доклад: Fourier quasicrystals and their generalizations, zeros of Dirichlet series, other almost periodic objects Допълнителна информация: https://icms.bg/fourier-quasicrystals-and-their-generalizations-zeros-of-dirichlet-series-other-almost-periodic-objects-icms-seminar-talk-by-sergey-favorov/ Резюме. A complex measure \mu on a d -dimensional Euclidean space is a crystalline measure (CM) if it is the temperate distribution, its distributional Fourier transform \hat\mu is also a measure, and supports of \mu and \hat\mu are discrete (locally finite); \mu is a Fourier quasicrystal (FQ) if, in addition, |\mu| and |\hat\mu| are also temperate distributions. For example, if \mu_0 is the sum of the unit masses at all points with integer coordinates, then by Poisson’s [...]

На 21 февруари 2025 г. (петък) от 13:00 часа в зала 578 на ИМИ ще се проведе присъствено заседание на семинара по „Алгебра и логика”. Доклад на тема: Classification of C*-algebras through the lens of Cartan subalgebras ще изнесе Ali Raad (Американски университет в България). Абстракт. C*-algebras were introduced in the last century following various attempts to mathematically formalize the foundations of quantum mechanics. As such they encapsulate the study of noncommutative topology, as every C*-algebra is an algebra of bounded operators on some Hilbert space. Over the years there has been a significant attempt to classify C*-algebras by an invariant consisting of K-theoretic and tracial data. A recent breakthrough result has shown that every classifiable C*-algebra has a distinguished Abelian subalgebra called a Cartan [...]