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X-WR-CALNAME:Institute of Mathematics and Informatics
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X-WR-CALDESC:Събития за Institute of Mathematics and Informatics
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BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231030T140000
DTEND;TZID=Europe/Sofia:20231030T153000
DTSTAMP:20260429T164611
CREATED:20231010T080439Z
LAST-MODIFIED:20231010T080439Z
UID:15119-1698674400-1698679800@math.bas.bg
SUMMARY:Семинар на МЦМН
DESCRIPTION:Дата: 30.10.2023 г.\, 14:00 ч. \nМясто: Зала 403\, ИМИ – БАН \nДокладчик: Петър Далаков\, ИМИ – БАН \nКурс: Introduction to Projective Structures and Opers \nРезюме: A complex projective structure on a Riemann surface is determined by an atlas\, whose transition functions are Moebius (fractional-linear) transformations. There are multiple   descriptions of these structures: as certain flat PGL_2-bundles\, as Sturm-Liouville operators\, as holomorphic connections on the (first) jet bundle of the dual of a theta-characteristic\, etc. This mini-course is an introduction to the fundamentals of projective structures\, accessible to students and non-specialists. We will also explore links to some classical geometric objects (such as quadratic differentials and Schwarzian derivatives)\, as well as some generalisations (G-opers) introduced by Beilinson and Drinfeld. \n\nIntroduction to Projective Structures and Opers\, course by Peter Dalakov \n\n  \n 
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bd%d0%b0-%d0%bc%d1%86%d0%bc%d0%bd-6/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231031T140000
DTEND;TZID=Europe/Sofia:20231031T153000
DTSTAMP:20260429T164611
CREATED:20231010T080721Z
LAST-MODIFIED:20231010T080721Z
UID:15124-1698760800-1698766200@math.bas.bg
SUMMARY:Семинар на МЦМН
DESCRIPTION:Дата: 31.10.2023 г.\, 14:00 ч. \nМясто: Зала 403\, ИМИ – БАН \nДокладчик: Петър Далаков\, ИМИ – БАН \nКурс: Introduction to Projective Structures and Opers \nРезюме: A complex projective structure on a Riemann surface is determined by an atlas\, whose transition functions are Moebius (fractional-linear) transformations. There are multiple   descriptions of these structures: as certain flat PGL_2-bundles\, as Sturm-Liouville operators\, as holomorphic connections on the (first) jet bundle of the dual of a theta-characteristic\, etc. This mini-course is an introduction to the fundamentals of projective structures\, accessible to students and non-specialists. We will also explore links to some classical geometric objects (such as quadratic differentials and Schwarzian derivatives)\, as well as some generalisations (G-opers) introduced by Beilinson and Drinfeld. \n\nIntroduction to Projective Structures and Opers\, course by Peter Dalakov \n\n  \n 
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bd%d0%b0-%d0%bc%d1%86%d0%bc%d0%bd-7/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231031T160000
DTEND;TZID=Europe/Sofia:20231031T173000
DTSTAMP:20260429T164611
CREATED:20231026T165751Z
LAST-MODIFIED:20231026T165751Z
UID:15291-1698768000-1698773400@math.bas.bg
SUMMARY:Семинар на секция "Математически основи на информатиката"
DESCRIPTION:На 31 октомври 2023 г. (вторник) от 16:00 часа в зала 578 на ИМИ-БАН\nще се проведе заседание на семинара на секция\n„Математически основи на информатиката”. \nДоклад ще изнесе д-р Константин Воробьов (ИМИ – БАН). \nАбстракт. In this work\, we consider the problem of determining the exact value of \(A_2(n\, {d\, d+2})\) defined as the maximal cardinality of a binary code of length \(n\) with two possible distances \(d\) and \(d+2\). We prove that for fixed even \(d\) and \(n\) big enough\, an optimal code must be a constant-weight code of weight \(d/2+1\) with possibly no more than one additional codeword of a different weight.\nWe also find exact values \(A_2(n\, {4\, 6})\) and \(A_2(n\, {6\, 8})\) starting from some \(n\). \nThis is a joint work with Ivan Landjev. \n 
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bd%d0%b0-%d1%81%d0%b5%d0%ba%d1%86%d0%b8%d1%8f-%d0%bc%d0%b0%d1%82%d0%b5%d0%bc%d0%b0%d1%82%d0%b8%d1%87%d0%b5%d1%81%d0%ba%d0%b8-%d0%be%d1%81%d0%bd%d0%be-19/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231102T140000
DTEND;TZID=Europe/Sofia:20231102T153000
DTSTAMP:20260429T164611
CREATED:20231010T081045Z
LAST-MODIFIED:20231010T081045Z
UID:15128-1698933600-1698939000@math.bas.bg
SUMMARY:Семинар на МЦМН
DESCRIPTION:Дата: 02.11.2023 г.\, 14:00 ч. \nМясто: Зала 403\, ИМИ – БАН \nДокладчик: Петър Далаков\, ИМИ – БАН \nКурс: Introduction to Projective Structures and Opers \nРезюме: A complex projective structure on a Riemann surface is determined by an atlas\, whose transition functions are Moebius (fractional-linear) transformations. There are multiple   descriptions of these structures: as certain flat PGL_2-bundles\, as Sturm-Liouville operators\, as holomorphic connections on the (first) jet bundle of the dual of a theta-characteristic\, etc. This mini-course is an introduction to the fundamentals of projective structures\, accessible to students and non-specialists. We will also explore links to some classical geometric objects (such as quadratic differentials and Schwarzian derivatives)\, as well as some generalisations (G-opers) introduced by Beilinson and Drinfeld. \n\nIntroduction to Projective Structures and Opers\, course by Peter Dalakov \n\n  \n 
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bd%d0%b0-%d0%bc%d1%86%d0%bc%d0%bd-8/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231103T130000
DTEND;TZID=Europe/Sofia:20231103T143000
DTSTAMP:20260429T164611
CREATED:20231026T161427Z
LAST-MODIFIED:20231026T161427Z
UID:15287-1699016400-1699021800@math.bas.bg
SUMMARY:Семинар "Алгебра и логика"
DESCRIPTION:На 3 ноември 2023 г. (петък) от 13:00 часа ще се проведе дистанционно заседание на семинара по „Алгебра и логика”. \nДоклад на тема: \nA Reduction of Temporary Coalitions in Infinite Multiplayer Games\nще изнесе Димитър Гелев. \nАбстракт. We propose a transformation of Concurrent Game Models which enables the reduction of infinite multiplayer games where players can form temporary coalitions to games with no coalitions by extending moves to include the negotiation steps that lead to the formation of coalitions. We adopt conditional promises as the building blocks of negotiation. Temporary coalitions and their agendas arise as the logical consequences of mutual promises. The transformation enables the use of established solution concepts about games with no coalitions for the analysis of games with temporary coalitions. \n\nЛинк към Zoom-стаята на семинара:\nhttps://us02web.zoom.us/j/85137375021?pwd=RE5QczdFTE1xL1R6MnI2b1lkcGczQT09 \n\n\n\n\nОт секция „Алгебра и логика” на ИМИ – БАН\nhttp://www.math.bas.bg/algebra/seminarAiL/\n============================== =====================
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%b0%d0%bb%d0%b3%d0%b5%d0%b1%d1%80%d0%b0-%d0%b8-%d0%bb%d0%be%d0%b3%d0%b8%d0%ba%d0%b0-104/
LOCATION:Zoom
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%A1%D0%B5%D0%BA%D1%86%D0%B8%D1%8F%20%D0%90%D0%BB%D0%B3%D0%B5%D0%B1%D1%80%D0%B0%20%D0%B8%20%D0%BB%D0%BE%D0%B3%D0%B8%D0%BA%D0%B0":MAILTO:algebra_logic_seminar@math.bas.bg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231106T140000
DTEND;TZID=Europe/Sofia:20231106T153000
DTSTAMP:20260429T164611
CREATED:20231010T081237Z
LAST-MODIFIED:20231010T081237Z
UID:15132-1699279200-1699284600@math.bas.bg
SUMMARY:Семинар на МЦМН
DESCRIPTION:Дата: 06.11.2023 г.\, 14:00 ч. \nМясто: Зала 403\, ИМИ – БАН \nДокладчик: Петър Далаков\, ИМИ – БАН \nКурс: Introduction to Projective Structures and Opers \nРезюме: A complex projective structure on a Riemann surface is determined by an atlas\, whose transition functions are Moebius (fractional-linear) transformations. There are multiple   descriptions of these structures: as certain flat PGL_2-bundles\, as Sturm-Liouville operators\, as holomorphic connections on the (first) jet bundle of the dual of a theta-characteristic\, etc. This mini-course is an introduction to the fundamentals of projective structures\, accessible to students and non-specialists. We will also explore links to some classical geometric objects (such as quadratic differentials and Schwarzian derivatives)\, as well as some generalisations (G-opers) introduced by Beilinson and Drinfeld. \n\nIntroduction to Projective Structures and Opers\, course by Peter Dalakov \n\n  \n 
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bd%d0%b0-%d0%bc%d1%86%d0%bc%d0%bd-9/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231107T140000
DTEND;TZID=Europe/Sofia:20231107T153000
DTSTAMP:20260429T164611
CREATED:20231103T065824Z
LAST-MODIFIED:20231103T065824Z
UID:15327-1699365600-1699371000@math.bas.bg
SUMMARY:Общ семинар на секция "Анализ\, геометрия и топология"
DESCRIPTION:Поредното заседание на Общия семинар на секция “Анализ\, геометрия и топология” ще се проведе\nна 7 ноември 2023 г. от 14:00 часа в зала 478 на ИМИ – БАН.\nДоклад на тема: \nNew and little known properties of the Fox and Fox-Wright functions\nще изнесе Dmitrii Karp\, Holon Institute of Technology\, Holon\, Israel. \nПоканват се всички интересуващи се. \nРезюме. In the talk\, I will introduce the functions H of Fox and W of Wright (its general case known as Fox-Wright function) and some motivation behind them. Then\, I will discuss the extension of Gauss’ expansion and summation formulas for the hypergeometric function to the case of general Fox-Wright function and Norlund’s expansion for the Meijer’s G function to the case of Fox’s H function. I will further present positivity conditions for the so-called delta-neutral case of Fox’s H function making it a probability distribution (widely used in statistics)\, which rely on complete monotonicity of certain product ratios of Gamma functions. Moreover\, I will exhibit a new integral equation for Fox’s H function and a conjecture regarding its zeros. Finally\, some open problems will be presented. \n\n 
URL:https://math.bas.bg/event/%d0%be%d0%b1%d1%89-%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bd%d0%b0-%d1%81%d0%b5%d0%ba%d1%86%d0%b8%d1%8f-%d0%b0%d0%bd%d0%b0%d0%bb%d0%b8%d0%b7-%d0%b3%d0%b5%d0%be%d0%bc%d0%b5%d1%82%d1%80%d0%b8-21/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%A1%D0%B5%D0%BA%D1%86%D0%B8%D1%8F%20%D0%90%D0%BD%D0%B0%D0%BB%D0%B8%D0%B7%2C%20%D0%B3%D0%B5%D0%BE%D0%BC%D0%B5%D1%82%D1%80%D0%B8%D1%8F%20%D0%B8%20%D1%82%D0%BE%D0%BF%D0%BE%D0%BB%D0%BE%D0%B3%D0%B8%D1%8F":MAILTO:vmil@math.bas.bg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231108T140000
DTEND;TZID=Europe/Sofia:20231108T153000
DTSTAMP:20260429T164611
CREATED:20231106T100342Z
LAST-MODIFIED:20231106T100342Z
UID:15346-1699452000-1699457400@math.bas.bg
SUMMARY:Национален семинар по стохастика
DESCRIPTION:Поредната сбирка на \nНационалния семинар по стохастика\nще се проведе на 8 ноември 2023 г. (сряда) от 14:00 часа в зала 503 на ИМИ – БАН. \nДоклад на тема \nHamiltonicity of randomly perturbed graphs\nще изнесе \nAlberto Espuny Díaz (Postdoctoral researcher at Universität Heidelberg\, Germany). \nАбстракт: In parallel to the development of smoothed analysis of algorithms\, the study of randomly perturbed graphs has thrived in the combinatorics community. The setup is the following: one considers a dense graph $H$ which fails to satisfy some increasing property and then sprinkles edges randomly until the property appears. A main goal in the area is to understand how many random edges are needed\, and which graphs $H$ are “worst” for this problem. \nIn this talk I will survey some results in the area and focus particularly on the Hamiltonicity problem\, which has often been used as a test for many techniques in graph theory. I will present several variants of the problem\, as well as some results for each of these variants. The talk is based on joint works with Alexander Allin\, António Girão\, and Joseph Hyde. \n 
URL:https://math.bas.bg/event/%d0%bd%d0%b0%d1%86%d0%b8%d0%be%d0%bd%d0%b0%d0%bb%d0%b5%d0%bd-%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bf%d0%be-%d1%81%d1%82%d0%be%d1%85%d0%b0%d1%81%d1%82%d0%b8%d0%ba%d0%b0-37/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%98%D0%BD%D1%81%D1%82%D0%B8%D1%82%D1%83%D1%82%20%D0%BF%D0%BE%20%D0%BC%D0%B0%D1%82%D0%B5%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20%D0%B8%20%D0%B8%D0%BD%D1%84%D0%BE%D1%80%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20-%20%D0%91%D0%90%D0%9D":MAILTO:office@math.bas.bg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231108T140000
DTEND;TZID=Europe/Sofia:20231108T153000
DTSTAMP:20260429T164611
CREATED:20231108T185838Z
LAST-MODIFIED:20231108T185838Z
UID:15391-1699452000-1699457400@math.bas.bg
SUMMARY:Национален семинар по стохастика
DESCRIPTION:Поредната сбирка на \nНационалния семинар по стохастика\nще се проведе на 15 ноември 2023 г. (сряда) от 14:00 часа в зала 503 на ИМИ – БАН. \nДоклад на тема \nAnti-concentration of Rademacher sums and Tomaszewski’s counterpart problem\nще изнесе \nJulien Portier\, University of Cambridge. \nАбстракт \n 
URL:https://math.bas.bg/event/%d0%bd%d0%b0%d1%86%d0%b8%d0%be%d0%bd%d0%b0%d0%bb%d0%b5%d0%bd-%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bf%d0%be-%d1%81%d1%82%d0%be%d1%85%d0%b0%d1%81%d1%82%d0%b8%d0%ba%d0%b0-38/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%98%D0%BD%D1%81%D1%82%D0%B8%D1%82%D1%83%D1%82%20%D0%BF%D0%BE%20%D0%BC%D0%B0%D1%82%D0%B5%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20%D0%B8%20%D0%B8%D0%BD%D1%84%D0%BE%D1%80%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20-%20%D0%91%D0%90%D0%9D":MAILTO:office@math.bas.bg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231108T160000
DTEND;TZID=Europe/Sofia:20231108T173000
DTSTAMP:20260429T164611
CREATED:20231106T052112Z
LAST-MODIFIED:20231106T052112Z
UID:15342-1699459200-1699464600@math.bas.bg
SUMMARY:Семинар по геометрия на МЦМН
DESCRIPTION:Следващото заседание на семинара по геометрия на МЦМН ще се проведе на\n8 ноември 2023 г.\, сряда\, от 16:00 ч. в зала 403 и онлайн. Доклад на тема \nTropicalizations II\nще изнесе Михаил Школников\, ИМИ – БАН. \nАбстракт: I will start by briefly recalling the two approaches to tropicalizing subvarieties of algebraic tori. We then transition to the compactified version\, substituting the torus with a toric variety\, and formalizing the concept of embedded tropical varieties together with a notion of their smoothness. Notably\, not all such varieties can be realized as tropicalizations of classical varieties\, and different embeddings of classical varieties yield combinatorially distinct tropicalizations\, which we equate through so-called modifications. We will conclude by addressing the question of recovering information about classical varieties from their tropicalizations\, exemplified by the phase tropical limit having the same topology as corresponding complex hypersurfaces provided that the usual tropicalization is smooth. \n\nTropicalizations II\, a talk by M. Shkolnikov \n\nZoom link:\n https://us02web.zoom.us/j/83740034721?pwd=VnBtcVpGUktscHQ4a09jZkNZTURyZz09
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bf%d0%be-%d0%b3%d0%b5%d0%be%d0%bc%d0%b5%d1%82%d1%80%d0%b8%d1%8f-%d0%bd%d0%b0-%d0%bc%d1%86%d0%bc%d0%bd/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231110T130000
DTEND;TZID=Europe/Sofia:20231110T143000
DTSTAMP:20260429T164611
CREATED:20231106T101108Z
LAST-MODIFIED:20231106T101108Z
UID:15351-1699621200-1699626600@math.bas.bg
SUMMARY:Семинар "Алгебра и логика"
DESCRIPTION:На 10 ноември 2023 г. (петък) от 13:00 часа ще се проведе хибридно заседание (присъствено в зала 578 на ИМИ-БАН и онлайн чрез платформата zoom) на семинара по „Алгебра и логика”. \nДоклад на тема: \nTransfinite version of the Mittag-Leffler condition for the vanishing of the derived limit\nще изнесе \nMishel Carelli (Technion – Israel Institute of Technology\, Israel). \nАбстракт. We give a necessary and sufficient condition for an inverse sequence  S0 ← S1 ← . . . indexed by natural numbers to have lim¹S = 0. This condition can be treated as a transfinite version of the Mittag-Leffler condition. We consider inverse sequences in the category of abelian groups. We also show that the class of inverse sequences S such that lim S = lim¹S = 0 is the least class of inverse sequences containing the trivial inverse sequence and closed with respect to small limits and a certain type of extensions. \nЛинк към Zoom-стаята на семинара:\nhttps://us02web.zoom.us/j/85137375021?pwd=RE5QczdFTE1xL1R6MnI2b1lkcGczQT09 \n\n\n\nОт секция „Алгебра и логика” на ИМИ – БАН\nhttp://www.math.bas.bg/algebra/seminarAiL/\n============================== =====================
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%b0%d0%bb%d0%b3%d0%b5%d0%b1%d1%80%d0%b0-%d0%b8-%d0%bb%d0%be%d0%b3%d0%b8%d0%ba%d0%b0-105/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%A1%D0%B5%D0%BA%D1%86%D0%B8%D1%8F%20%D0%90%D0%BB%D0%B3%D0%B5%D0%B1%D1%80%D0%B0%20%D0%B8%20%D0%BB%D0%BE%D0%B3%D0%B8%D0%BA%D0%B0":MAILTO:algebra_logic_seminar@math.bas.bg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231110T140000
DTEND;TZID=Europe/Sofia:20231110T153000
DTSTAMP:20260429T164611
CREATED:20231106T143730Z
LAST-MODIFIED:20231106T144427Z
UID:15357-1699624800-1699630200@math.bas.bg
SUMMARY:Семинар на секция "Математически основи на информатиката"
DESCRIPTION:На 10 ноември 2023 г. (вторник) от 14:00 часа в зала 478 на ИМИ-БАН\nще се проведе заседание на семинара на секция\n„Математически основи на информатиката”. \nДоклад на тема \nOn induced \(C_4\)-free graphs with high average degree\nще изнесе Антонио Жирао. \nАбстракт.  A long-standing conjecture of Thomassen from the 80’s states that every graph with sufficiently high average degree contains a subgraph with high girth and still preserving large enough average degree. This conjecture has only been resolved in the early 2000’s by Kühn and Osthus in the first non-trivial case i.e. they showed that for every \(k\)\, there is \(f(k)\) such the every graph with average degree at least \(f(k)\) contains a subgraph which is \(C_4\)-free with average degree \(k\). \nWe will talk about a recent result which strengthens this result of Kühn and Osthus in two ways. First\, we prove an analogous induced version and secondly we give much better bounds for the function f allowing us obtain few non-trivial results as simple corollaries. Finally\, we use these methods to confirm a conjecture Bonamy et al.\nАнтонио Жирао e пост-докторант в Оксфордския Университет под ръководството на проф. Алекс Скот. Преди да заеме тази позиция\, Антонио работи като пост-докторант в Хайделбергския Университет под ръководството на проф. Феликс Йоос и в Университета в Бирмингам под ръководството на проф. Даниела Кюн и проф. Дерек Остюс. Защитава докторантурата в Университета в Кеймбридж под ръководството на проф. Бела Болобаш през 2018 г.
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bd%d0%b0-%d1%81%d0%b5%d0%ba%d1%86%d0%b8%d1%8f-%d0%bc%d0%b0%d1%82%d0%b5%d0%bc%d0%b0%d1%82%d0%b8%d1%87%d0%b5%d1%81%d0%ba%d0%b8-%d0%be%d1%81%d0%bd%d0%be-20/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231114T140000
DTEND;TZID=Europe/Sofia:20231114T153000
DTSTAMP:20260429T164611
CREATED:20231010T083449Z
LAST-MODIFIED:20231010T090357Z
UID:15136-1699970400-1699975800@math.bas.bg
SUMMARY:Семинар на МЦМН
DESCRIPTION:Дата: 14.11.2023 г.\, 14:00 ч. \nМясто: Зала 403\, ИМИ – БАН \nДокладчик: Валдемар Цанов\, ИМИ – БАН \nКурс: Invariant theory\, homogeneous projective varieties\, and momentum maps \nРезюме: Let \(f:K\to U(V)\) be a unitary representation of a compact Lie group \(K\) with Lie algebra \(\mathfrak k\). This series of talks will be devoted to some recent developments based on relations between the following three classical notions. \n\nThe ring of -invariant polynomials \(\mathbb C[V]^K\) is finitely generated by homogeneous elements\, by a theorem of Hilbert\, but the proof is notoriously nonconstructive. The degrees of a minimal set of generators are canonically determined by \(f\)\, and will be the focus of the discussion.\nThe \(K\)-equivariant momentum map \(\mu:\mathbb P(V)\to \mathfrak k^*\) associated to the Fubini-Study form encodes in its image properties of the invariant ring \(\mathbb C[V]^K\) and the \(K\)-module structure of the entire polynomial ring \(\mathbb C[V]\)\, due to theorems of Mumford and Brion. While many general properties of momentum images have been established\, explicit descriptions remain unknown in many cases south for in physics and quantum information theory.\nProjective geometry of complex \(K\)-orbits in \(\mathbb P(V)\); their fundamental forms\, osculating varieties and secant varieties.\n\nGeneral relations between the first two topics are well established\, even in a more general context. There are also well known relations between invariant theory and projective geometry\, but secant varieties have only recently been brought to the discussion and are subject of current interest. \nAfter introducing the basic notions\, I will derive some properties of momentum images related to fundamental forms and osculating varieties\, as well as a lower bound on the minimal positive degree of a homogeneous invariant\, derived using secant varieties. At the end I will present a class of homogeneous projective varieties\, characterized by a special property of their secant varieties\, where the relations between the above three concepts take a particularly pristine form. \n\nInvariant theory\, homogeneous projective varieties\, and momentum maps\, course by Valdemar Tsanov \n\n 
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bd%d0%b0-%d0%bc%d1%86%d0%bc%d0%bd-10/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231114T140000
DTEND;TZID=Europe/Sofia:20231114T153000
DTSTAMP:20260429T164611
CREATED:20231110T170235Z
LAST-MODIFIED:20231110T170235Z
UID:15406-1699970400-1699975800@math.bas.bg
SUMMARY:Семинар по Приложна математика
DESCRIPTION:How log-concavity fought lottery frauds in Florida and what it did after winning\nДокладчик: Дмитри Карп\nДата: 14.11.2023 г.\nЧас: 14:00 ч.\nМясто: Зала 503 на ИМИ-БАН \nРезюме: In the talk I will first discuss the log-concavity in parameters of the normalized beta function (which represents the cumulative distribution function of beta distributed random variable) that has been used recently in an investigation of lottery frauds in Florida.  I will then present some related  properties of incomplete beta function and proceed to general log-concavity problems and their particular cases motivated by various problems in statistics\, probability and analysis. \nФейсбук страница на семинара: Семинар по Приложна математика
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bf%d0%be-%d0%bf%d1%80%d0%b8%d0%bb%d0%be%d0%b6%d0%bd%d0%b0-%d0%bc%d0%b0%d1%82%d0%b5%d0%bc%d0%b0%d1%82%d0%b8%d0%ba%d0%b0-7/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%98%D0%BD%D1%81%D1%82%D0%B8%D1%82%D1%83%D1%82%20%D0%BF%D0%BE%20%D0%BC%D0%B0%D1%82%D0%B5%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20%D0%B8%20%D0%B8%D0%BD%D1%84%D0%BE%D1%80%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20-%20%D0%91%D0%90%D0%9D":MAILTO:office@math.bas.bg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231114T161500
DTEND;TZID=Europe/Sofia:20231114T173000
DTSTAMP:20260429T164611
CREATED:20231110T160109Z
LAST-MODIFIED:20231110T160109Z
UID:15397-1699978500-1699983000@math.bas.bg
SUMMARY:Национален колоквиум по математика
DESCRIPTION:СЪЮЗ НА МАТЕМАТИЦИТЕ В БЪЛГАРИЯ\n\nИНСТИТУТ ПО МАТЕМАТИКА И ИНФОРМАТИКА – БАН \n\n\n\nНАЦИОНАЛЕН КОЛОКВИУМ ПО МАТЕМАТИКА\n\n​Поредната сбирка на Колоквиума ще се състои на 14 ноември 2023 г. (вторник)  от 16:15 часа в Заседателната зала на ИМИ – БАН. Доклад на тема:\n\nArcs of High Divisibility and Their Applications to Coding Theory\nще изнесе проф. дмн Иван Ланджев\,\nИнститут по матем​атика и информатика\, Българска академия на науките. \n\n\n​Резюме
URL:https://math.bas.bg/event/%d0%bd%d0%b0%d1%86%d0%b8%d0%be%d0%bd%d0%b0%d0%bb%d0%b5%d0%bd-%d0%ba%d0%be%d0%bb%d0%be%d0%ba%d0%b2%d0%b8%d1%83%d0%bc-%d0%bf%d0%be-%d0%bc%d0%b0%d1%82%d0%b5%d0%bc%d0%b0%d1%82%d0%b8%d0%ba%d0%b0-26/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%A1%D1%8A%D1%8E%D0%B7%20%D0%BD%D0%B0%20%D0%BC%D0%B0%D1%82%D0%B5%D0%BC%D0%B0%D1%82%D0%B8%D1%86%D0%B8%D1%82%D0%B5%20%D0%B2%20%D0%91%D1%8A%D0%BB%D0%B3%D0%B0%D1%80%D0%B8%D1%8F":MAILTO:smb.sofia@gmail.com
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231115T160000
DTEND;TZID=Europe/Sofia:20231115T173000
DTSTAMP:20260429T164611
CREATED:20231110T165607Z
LAST-MODIFIED:20231110T165607Z
UID:15402-1700064000-1700069400@math.bas.bg
SUMMARY:Семинар по геометрия на МЦМН
DESCRIPTION:Следващата сбирка на Семинара по геометрия на МЦМН\nще се проведе в сряда\, 15 ноември 2023 г. от 16:00 ч. в зала 403 и онлайн в Zoom:\n\nTopics in non-archimedean analytic geometry (I)\, \nby Jiachang Xu – International Center for Mathematical Sciences (ICMS – Sofia)\n\nZoom link:\n\nhttps://us02web.zoom.us/j/83740034721?pwd=VnBtcVpGUktscHQ4a09jZkNZTURyZz09
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bf%d0%be-%d0%b3%d0%b5%d0%be%d0%bc%d0%b5%d1%82%d1%80%d0%b8%d1%8f-%d0%bd%d0%b0-%d0%bc%d1%86%d0%bc%d0%bd-2/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%98%D0%BD%D1%81%D1%82%D0%B8%D1%82%D1%83%D1%82%20%D0%BF%D0%BE%20%D0%BC%D0%B0%D1%82%D0%B5%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20%D0%B8%20%D0%B8%D0%BD%D1%84%D0%BE%D1%80%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20-%20%D0%91%D0%90%D0%9D":MAILTO:office@math.bas.bg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231116T140000
DTEND;TZID=Europe/Sofia:20231116T153000
DTSTAMP:20260429T164611
CREATED:20231010T091536Z
LAST-MODIFIED:20231010T091536Z
UID:15145-1700143200-1700148600@math.bas.bg
SUMMARY:Семинар на МЦМН
DESCRIPTION:Дата: 16.11.2023 г.\, 14:00 ч. \nМясто: Зала 403\, ИМИ – БАН \nДокладчик: Валдемар Цанов\, ИМИ – БАН \nКурс: Invariant theory\, homogeneous projective varieties\, and momentum maps \nРезюме: Let \(f:K\to U(V)\) be a unitary representation of a compact Lie group \(K\) with Lie algebra \(\mathfrak k\). This series of talks will be devoted to some recent developments based on relations between the following three classical notions. \n\nThe ring of -invariant polynomials \(\mathbb C[V]^K\) is finitely generated by homogeneous elements\, by a theorem of Hilbert\, but the proof is notoriously nonconstructive. The degrees of a minimal set of generators are canonically determined by \(f\)\, and will be the focus of the discussion.\nThe \(K\)-equivariant momentum map \(\mu:\mathbb P(V)\to \mathfrak k^*\) associated to the Fubini-Study form encodes in its image properties of the invariant ring \(\mathbb C[V]^K\) and the \(K\)-module structure of the entire polynomial ring \(\mathbb C[V]\)\, due to theorems of Mumford and Brion. While many general properties of momentum images have been established\, explicit descriptions remain unknown in many cases south for in physics and quantum information theory.\nProjective geometry of complex \(K\)-orbits in \(\mathbb P(V)\); their fundamental forms\, osculating varieties and secant varieties.\n\nGeneral relations between the first two topics are well established\, even in a more general context. There are also well known relations between invariant theory and projective geometry\, but secant varieties have only recently been brought to the discussion and are subject of current interest. \nAfter introducing the basic notions\, I will derive some properties of momentum images related to fundamental forms and osculating varieties\, as well as a lower bound on the minimal positive degree of a homogeneous invariant\, derived using secant varieties. At the end I will present a class of homogeneous projective varieties\, characterized by a special property of their secant varieties\, where the relations between the above three concepts take a particularly pristine form. \n\nInvariant theory\, homogeneous projective varieties\, and momentum maps\, course by Valdemar Tsanov \n\n 
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bd%d0%b0-%d0%bc%d1%86%d0%bc%d0%bd-11/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231117T130000
DTEND;TZID=Europe/Sofia:20231117T143000
DTSTAMP:20260429T164611
CREATED:20231114T182803Z
LAST-MODIFIED:20231114T182803Z
UID:15410-1700226000-1700231400@math.bas.bg
SUMMARY:Семинар "Алгебра и логика"
DESCRIPTION:На 17 ноември 2023 г. (петък) от 13:00 часа ще се проведе хибридно заседание (присъствено в зала 578 на ИМИ-БАН и онлайн чрез платформата zoom) на семинара по „Алгебра и логика”. \nДоклад на тема: \nNoncommutative invariants of dihedral groups\nще изнесе \nБоян Костадинов\, ИМИ – БАН. \nАбстракт. We consider the 2-generated free metabelian associative and Lie algebras over the complex field and the invariants of the dihedral groups of finite order acting on these algebras. In the associative case we find a finite set of generators of the algebra of invariants. In the Lie case\, when the algebra of invariants is not finitely generated\, we give a minimal system of generators of the invariants in the commutator ideal as a module of the algebra of the invariants in the polynomial algebra in two variables. In both associative and Lie cases we compute the Hilbert series of the algebras of invariants.\nThe results are obtained jointly with Vesselin Drensky. \nЛинк към Zoom-стаята на семинара:\nhttps://us02web.zoom.us/j/85137375021?pwd=RE5QczdFTE1xL1R6MnI2b1lkcGczQT09 \n\n\n\nОт секция „Алгебра и логика” на ИМИ – БАН\nhttp://www.math.bas.bg/algebra/seminarAiL/\n============================== =====================
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%b0%d0%bb%d0%b3%d0%b5%d0%b1%d1%80%d0%b0-%d0%b8-%d0%bb%d0%be%d0%b3%d0%b8%d0%ba%d0%b0-106/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%A1%D0%B5%D0%BA%D1%86%D0%B8%D1%8F%20%D0%90%D0%BB%D0%B3%D0%B5%D0%B1%D1%80%D0%B0%20%D0%B8%20%D0%BB%D0%BE%D0%B3%D0%B8%D0%BA%D0%B0":MAILTO:algebra_logic_seminar@math.bas.bg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231120T143000
DTEND;TZID=Europe/Sofia:20231120T160000
DTSTAMP:20260429T164611
CREATED:20231116T054743Z
LAST-MODIFIED:20231116T054743Z
UID:15415-1700490600-1700496000@math.bas.bg
SUMMARY:Семинар "Дидактическо моделиране"
DESCRIPTION:Поредната сбирка на семинара \nДидактическо моделиране\nще се проведе на 20.11.2023 г. от 14:30 ч. в зала 278 на ИМИ. \nДоклад на тема \nТочкуване на задачи и използване на скàли при стандартизирани оценявания\nще изнесe \nпроф. Кирил Банков.
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%b4%d0%b8%d0%b4%d0%b0%d0%ba%d1%82%d0%b8%d1%87%d0%b5%d1%81%d0%ba%d0%be-%d0%bc%d0%be%d0%b4%d0%b5%d0%bb%d0%b8%d1%80%d0%b0%d0%bd%d0%b5-34/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231121T140000
DTEND;TZID=Europe/Sofia:20231121T153000
DTSTAMP:20260429T164611
CREATED:20231010T091730Z
LAST-MODIFIED:20231010T091730Z
UID:15149-1700575200-1700580600@math.bas.bg
SUMMARY:Семинар на МЦМН
DESCRIPTION:Дата: 21.11.2023 г.\, 14:00 ч. \nМясто: Зала 403\, ИМИ – БАН \nДокладчик: Валдемар Цанов\, ИМИ – БАН \nКурс: Invariant theory\, homogeneous projective varieties\, and momentum maps \nРезюме: Let \(f:K\to U(V)\) be a unitary representation of a compact Lie group \(K\) with Lie algebra \(\mathfrak k\). This series of talks will be devoted to some recent developments based on relations between the following three classical notions. \n\nThe ring of -invariant polynomials \(\mathbb C[V]^K\) is finitely generated by homogeneous elements\, by a theorem of Hilbert\, but the proof is notoriously nonconstructive. The degrees of a minimal set of generators are canonically determined by \(f\)\, and will be the focus of the discussion.\nThe \(K\)-equivariant momentum map \(\mu:\mathbb P(V)\to \mathfrak k^*\) associated to the Fubini-Study form encodes in its image properties of the invariant ring \(\mathbb C[V]^K\) and the \(K\)-module structure of the entire polynomial ring \(\mathbb C[V]\)\, due to theorems of Mumford and Brion. While many general properties of momentum images have been established\, explicit descriptions remain unknown in many cases south for in physics and quantum information theory.\nProjective geometry of complex \(K\)-orbits in \(\mathbb P(V)\); their fundamental forms\, osculating varieties and secant varieties.\n\nGeneral relations between the first two topics are well established\, even in a more general context. There are also well known relations between invariant theory and projective geometry\, but secant varieties have only recently been brought to the discussion and are subject of current interest. \nAfter introducing the basic notions\, I will derive some properties of momentum images related to fundamental forms and osculating varieties\, as well as a lower bound on the minimal positive degree of a homogeneous invariant\, derived using secant varieties. At the end I will present a class of homogeneous projective varieties\, characterized by a special property of their secant varieties\, where the relations between the above three concepts take a particularly pristine form. \n\nInvariant theory\, homogeneous projective varieties\, and momentum maps\, course by Valdemar Tsanov \n\n 
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bd%d0%b0-%d0%bc%d1%86%d0%bc%d0%bd-12/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231122T160000
DTEND;TZID=Europe/Sofia:20231122T173000
DTSTAMP:20260429T164611
CREATED:20231121T164225Z
LAST-MODIFIED:20231121T164225Z
UID:15481-1700668800-1700674200@math.bas.bg
SUMMARY:Семинар по геометрия на МЦМН
DESCRIPTION:Следващата сбирка на Семинара по геометрия на МЦМН\nще се проведе в сряда\, 22 ноември 2023 г. от 16:00 ч. в зала 403 и онлайн в Zoom:\n\n\nTopics in non-archimedean analytic geometry (II)\n\nby Jiachang Xu – International Center for Mathematical Sciences (ICMS – Sofia)\n\nZoom link:\n\nhttps://us02web.zoom.us/j/83740034721?pwd=VnBtcVpGUktscHQ4a09jZkNZTURyZz09
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bf%d0%be-%d0%b3%d0%b5%d0%be%d0%bc%d0%b5%d1%82%d1%80%d0%b8%d1%8f-%d0%bd%d0%b0-%d0%bc%d1%86%d0%bc%d0%bd-3/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%98%D0%BD%D1%81%D1%82%D0%B8%D1%82%D1%83%D1%82%20%D0%BF%D0%BE%20%D0%BC%D0%B0%D1%82%D0%B5%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20%D0%B8%20%D0%B8%D0%BD%D1%84%D0%BE%D1%80%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20-%20%D0%91%D0%90%D0%9D":MAILTO:office@math.bas.bg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231123T140000
DTEND;TZID=Europe/Sofia:20231123T153000
DTSTAMP:20260429T164611
CREATED:20231010T091918Z
LAST-MODIFIED:20231010T091918Z
UID:15153-1700748000-1700753400@math.bas.bg
SUMMARY:Семинар на МЦМН
DESCRIPTION:Дата: 23.11.2023 г.\, 14:00 ч. \nМясто: Зала 403\, ИМИ – БАН \nДокладчик: Валдемар Цанов\, ИМИ – БАН \nКурс: Invariant theory\, homogeneous projective varieties\, and momentum maps \nРезюме: Let \(f:K\to U(V)\) be a unitary representation of a compact Lie group \(K\) with Lie algebra \(\mathfrak k\). This series of talks will be devoted to some recent developments based on relations between the following three classical notions. \n\nThe ring of -invariant polynomials \(\mathbb C[V]^K\) is finitely generated by homogeneous elements\, by a theorem of Hilbert\, but the proof is notoriously nonconstructive. The degrees of a minimal set of generators are canonically determined by \(f\)\, and will be the focus of the discussion.\nThe \(K\)-equivariant momentum map \(\mu:\mathbb P(V)\to \mathfrak k^*\) associated to the Fubini-Study form encodes in its image properties of the invariant ring \(\mathbb C[V]^K\) and the \(K\)-module structure of the entire polynomial ring \(\mathbb C[V]\)\, due to theorems of Mumford and Brion. While many general properties of momentum images have been established\, explicit descriptions remain unknown in many cases south for in physics and quantum information theory.\nProjective geometry of complex \(K\)-orbits in \(\mathbb P(V)\); their fundamental forms\, osculating varieties and secant varieties.\n\nGeneral relations between the first two topics are well established\, even in a more general context. There are also well known relations between invariant theory and projective geometry\, but secant varieties have only recently been brought to the discussion and are subject of current interest. \nAfter introducing the basic notions\, I will derive some properties of momentum images related to fundamental forms and osculating varieties\, as well as a lower bound on the minimal positive degree of a homogeneous invariant\, derived using secant varieties. At the end I will present a class of homogeneous projective varieties\, characterized by a special property of their secant varieties\, where the relations between the above three concepts take a particularly pristine form. \n\nInvariant theory\, homogeneous projective varieties\, and momentum maps\, course by Valdemar Tsanov \n\n 
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bd%d0%b0-%d0%bc%d1%86%d0%bc%d0%bd-13/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231124T130000
DTEND;TZID=Europe/Sofia:20231124T150000
DTSTAMP:20260429T164611
CREATED:20231120T160634Z
LAST-MODIFIED:20231121T083451Z
UID:15474-1700830800-1700838000@math.bas.bg
SUMMARY:Семинар "Алгебра и логика"
DESCRIPTION:На 24 ноември 2023 г. (петък) от 13:00 часа ще се проведе дистанционно заседание на семинара по „Алгебра и логика”\, на който ще бъдат изнесени два доклада. \nОт 13:00 ч. Димитринка Владева (ИМИ-БАН) ще изнесе доклад на тема \nCatalan numbers and additively idempotent semirings\nОт 14:00 ч. Русанка Луканова (ИМИ-БАН) ще изнесе доклад на тема \nSemantics of Propositional Attitudes in Type-Theory of Algorithms\n  \nЗаглавие: Catalan numbers and additively idempotent semirings \nАбстракт. The purpose of the present talk is to provide new applications of remarkable Catalan numbers. In Richard Stanley’s book Enumerative Combinatorics\, Volume II (Cambridge University Press) there are many combinatorial objects that are counted by the Catalan numbers as well as applications in graph theory\, Young diagrams\, lattice theory\, real matrices\, real polynomials and so on. We show applications of Catalan numbers in some additively idempotent semirings which appeared in my results in 5 papers published between 2011 and 2023. \nThe set of nilpotent endomorphisms in the endomorphism semiring of a finite chain is a semiring of order (n – 1)th Catalan number and is an ideal in another semiring of order n th Catalan number. The semiring of k th nilpotent endomorphisms\, where 0 ≤ k ≤ n – 1 is of order a product of two Catalan numbers. By complex products of Catalan numbers we describe the roots of arbitrary idempotent of the endomorphism semiring of a finite chain.\nIn an additively idempotent semiring which is a generalization of the endomorphism semiring of a finite chain considered as a simplex we prove that the subsimplex of nilpotent elements is of order (n – 1) th Catalan number and it is closed under derivations which are projections of the simplex to some simplices.\nIn the last paper\, 2023\, we prove that an additively idempotent semiring which is an S0-semialgebra\, where S0 is a commutative additively idempotent semiring\, and with a finite basis of a special type is isomorphic to a matrix semiring. As a consequence we obtain two different semirings of upper triangular matrices over the Boolean semiring\, which are of order (n + 1) th Catalan number.\n\n\nЗаглавие: Semantics of Propositional Attitudes in Type-Theory of Algorithms \nАбстракт. Natural language (NL) is notorious for various kinds of ambiguities.  Among the most difficult ones\, for computational handling of NL\, are expressions with multiple occurrences of quantifiers\, which contribute to quantifier scope ambiguities. Far more difficult for computational linguistics are NL expressions having occurrences of so-called attitude components designating knowledge\, believes\, statements\, and similar semantic information. \nOften\, the syntactic complement of an attitude lexeme is a sentential expression. The sentential complement may have subexpressions that designate semantic information belonging to varying scopes.  Depending on context\, some components can be semantic parts of the attitudinal information\, which is in the scope of the propositional attitude\, or external to it. \nThe first formal representation of NL attitudes was by Montague\, 1973\, along with the quantifier scope ambiguities\, by the notions of extension and intension\, and using extra-syntactic disambiguation of NL expressions. That approach\, while unsatisfactory in important aspects\, was adopted and adapted by some variants of Montague grammars\, for specific purposes. The problem has been largely open\, due to its purely semantic nature and computational difficulties\, without direct syntactic appearance. \nThe semantic phenomena of attitudes include statements in natural language\, including in the domains of mathematical texts and proofs. \nIn this presentation of a recent paper\, I extend the type-theory of algorithms\, to cover algorithmic semantics of some of the major attitude expressions and their semantic underspecification. I provide reduction calculus for deriving semantic specifications in contexts. \n  \n\nЛинк към Zoom-стаята на семинара:\nhttps://us02web.zoom.us/j/85137375021?pwd=RE5QczdFTE1xL1R6MnI2b1lkcGczQT09 \n\n\n\nОт секция „Алгебра и логика” на ИМИ – БАН\nhttp://www.math.bas.bg/algebra/seminarAiL/\n============================== =====================
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%b0%d0%bb%d0%b3%d0%b5%d0%b1%d1%80%d0%b0-%d0%b8-%d0%bb%d0%be%d0%b3%d0%b8%d0%ba%d0%b0-107/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%A1%D0%B5%D0%BA%D1%86%D0%B8%D1%8F%20%D0%90%D0%BB%D0%B3%D0%B5%D0%B1%D1%80%D0%B0%20%D0%B8%20%D0%BB%D0%BE%D0%B3%D0%B8%D0%BA%D0%B0":MAILTO:algebra_logic_seminar@math.bas.bg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231128T140000
DTEND;TZID=Europe/Sofia:20231128T153000
DTSTAMP:20260429T164611
CREATED:20231123T092255Z
LAST-MODIFIED:20231123T092255Z
UID:15484-1701180000-1701185400@math.bas.bg
SUMMARY:Семинар "Математическо моделиране и числен анализ"
DESCRIPTION:Семинарът на секция “Математическо моделиране и числен анализ” ще продължи своята работа. \nДата: 28.11.2023 г.\, 14:00 ч. \nМясто: Заседателната зала на ИМИ – БАН \nТема: Приложение на математически и статистически модели и методи в областта на мониторинга на горите и земеделските земи с използване на данни от дистанционни изследвания \nДокладчици: Проф. д-р Лъчезар Филчев\,\nгл. ас. д-р Десислава Ганева\,\nгл. ас. д-р Илина Каменова и\nгл. ас. д-р Златомир Димитров\nот ИКИТ-БАН \nРезюме: Темата изследва как да се използват математически и статистически модели и методи за мониторинг на горите и земеделските земи с данни от  дистанционни изследвания. Тя цели да се подобри управлението на екосистемите  и хранителната сигурност чрез оценка на рисковете и възможностите\, свързани с тези области. Тя има много приложения в областта на картографията\, биометрията\, агрономията и природозащитата.
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bc%d0%b0%d1%82%d0%b5%d0%bc%d0%b0%d1%82%d0%b8%d1%87%d0%b5%d1%81%d0%ba%d0%be-%d0%bc%d0%be%d0%b4%d0%b5%d0%bb%d0%b8%d1%80%d0%b0%d0%bd%d0%b5-%d0%b8-%d1%87-5/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231128T140000
DTEND;TZID=Europe/Sofia:20231128T153000
DTSTAMP:20260429T164611
CREATED:20231123T142102Z
LAST-MODIFIED:20231123T142102Z
UID:15514-1701180000-1701185400@math.bas.bg
SUMMARY:Научен семинар на ВНЗ "Информационно моделиране"
DESCRIPTION:На 28 ноември (вторник)\, от 14 ч.\, в зала 578 на ИМИ-БАН\,\nще се проведе научен семинар на ВНЗ “Информационно моделиране”.\nДоклад ще изнесе редовният докторант Светослав Хаджииванов на тема: \nRevolutionizing .NET with the Actor Model: The End of Traditional Encapsulation?\nAbstract: The actor model is revolutionizing the way we build applications by moving past the traditional idea of encapsulation in object-oriented programming. This model is perfect for today’s computers with multiple CPU cores\, where old-school methods fall short\, leading to race conditions and other concurrency issues. In this seminar\, we’ll introduce you to the basics of this effective approach. Proto.Actor\, our toolkit of choice\, blends the strength of both new and time-tested practices\, making it a solid fit for industries from banking to healthcare. We’ll dig into the actor model’s origins and its capacity for running many tasks smoothly and efficiently\, ensuring our systems are reliable even when some parts fail. \nЗа дистанционно включване: \nJoin Zoom Meeting\nhttps://us02web.zoom.us/j/87619474903?pwd=UWxpWjVIa1dNRE1LSzhTYU41dC8wQT09 \nMeeting ID: 876 1947 4903\nPasscode: 746882
URL:https://math.bas.bg/event/%d0%bd%d0%b0%d1%83%d1%87%d0%b5%d0%bd-%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bd%d0%b0-%d0%b2%d0%bd%d0%b7-%d0%b8%d0%bd%d1%84%d0%be%d1%80%d0%bc%d0%b0%d1%86%d0%b8%d0%be%d0%bd%d0%bd%d0%be-%d0%bc/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%A1%D0%B5%D0%BA%D1%86%D0%B8%D1%8F%20%D0%98%D0%BD%D1%84%D0%BE%D1%80%D0%BC%D0%B0%D1%82%D0%B8%D1%87%D0%BD%D0%BE%20%D0%BC%D0%BE%D0%B4%D0%B5%D0%BB%D0%B8%D1%80%D0%B0%D0%BD%D0%B5%20%28%D0%92%D0%9D%D0%97%29":MAILTO:stoyan@math.bas.bg
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BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231201T130000
DTEND;TZID=Europe/Sofia:20231201T143000
DTSTAMP:20260429T164611
CREATED:20231129T101726Z
LAST-MODIFIED:20231129T104247Z
UID:15526-1701435600-1701441000@math.bas.bg
SUMMARY:Семинар "Алгебра и логика"
DESCRIPTION:На 1 декември 2023 г. (петък) от 13:00 часа ще се проведе хибридно заседание (присъствено в зала 578 на ИМИ-БАН и онлайн чрез платформата zoom) на семинара по „Алгебра и логика”. \nДоклад на тема: \nCharacterization of Ideals of Q-algebras Related to its G-part\nще изнесе \nдоц. Йорг Копиц\, ИМИ – БАН. \nАбстракт. In this presentation\, we study the \(G\)-part of \(Q\)-algebras \(X\)\, i.e. the set \(G(X)=\{x\in X:0x=x\}\). We show that \(G(X)\) is an abelian group\, whenever \(G(X)\) is an ideal and characterize all \(Q\)-algebras \(X\) such that \(G(X)\) is an ideal of \(X\). Moreover\, we show that\, up to isomorphism\, there is only one \(Q\)-algebra \(X\) with \(G(X)=X\)\, which is only possible if \(|X|=2^{k}\) (\(k\in \mathbb{N}\)). \nЛинк към Zoom-стаята на семинара:\nhttps://us02web.zoom.us/j/85137375021?pwd=RE5QczdFTE1xL1R6MnI2b1lkcGczQT09 \n\n\n\nОт секция „Алгебра и логика” на ИМИ – БАН\nhttp://www.math.bas.bg/algebra/seminarAiL/\n============================== =====================
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%b0%d0%bb%d0%b3%d0%b5%d0%b1%d1%80%d0%b0-%d0%b8-%d0%bb%d0%be%d0%b3%d0%b8%d0%ba%d0%b0-108/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%A1%D0%B5%D0%BA%D1%86%D0%B8%D1%8F%20%D0%90%D0%BB%D0%B3%D0%B5%D0%B1%D1%80%D0%B0%20%D0%B8%20%D0%BB%D0%BE%D0%B3%D0%B8%D0%BA%D0%B0":MAILTO:algebra_logic_seminar@math.bas.bg
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BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231204T130000
DTEND;TZID=Europe/Sofia:20231204T163000
DTSTAMP:20260429T164611
CREATED:20231129T110158Z
LAST-MODIFIED:20231129T110646Z
UID:15534-1701694800-1701707400@math.bas.bg
SUMMARY:Годишна отчетна сесия на секция "Анализ\, геометрия и топология"
DESCRIPTION:Годишната отчетна сесия на секция „Анализ\, геометрия и топология“ \nще се проведе на 4 декември (понеделник) от 13:00 ч. в зала 478 на ИМИ-БАН. \nПРОГРАМА
URL:https://math.bas.bg/event/%d0%b3%d0%be%d0%b4%d0%b8%d1%88%d0%bd%d0%b0-%d0%be%d1%82%d1%87%d0%b5%d1%82%d0%bd%d0%b0-%d1%81%d0%b5%d1%81%d0%b8%d1%8f-%d0%bd%d0%b0-%d1%81%d0%b5%d0%ba%d1%86%d0%b8%d1%8f-%d0%b0%d0%bd%d0%b0%d0%bb%d0%b8/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Работен семинар
ORGANIZER;CN="%D0%A1%D0%B5%D0%BA%D1%86%D0%B8%D1%8F%20%D0%90%D0%BD%D0%B0%D0%BB%D0%B8%D0%B7%2C%20%D0%B3%D0%B5%D0%BE%D0%BC%D0%B5%D1%82%D1%80%D0%B8%D1%8F%20%D0%B8%20%D1%82%D0%BE%D0%BF%D0%BE%D0%BB%D0%BE%D0%B3%D0%B8%D1%8F":MAILTO:vmil@math.bas.bg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231205T140000
DTEND;TZID=Europe/Sofia:20231205T153000
DTSTAMP:20260429T164611
CREATED:20231010T092252Z
LAST-MODIFIED:20231130T141804Z
UID:15157-1701784800-1701790200@math.bas.bg
SUMMARY:Семинар на МЦМН
DESCRIPTION:Дата: 05.12.2023 г.\, 14:00 ч. \nМясто: Зала 403\, ИМИ – БАН \nДокладчик: Богдан Станков\, ИМИ – БАН \nДоклад: Recent developments in the study of Følner functions \nДопълнителна информация: https://icms.bg/recent-developments-in-the-study-of-folner-functions-talk-by-bogdan-stankov/
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bd%d0%b0-%d0%bc%d1%86%d0%bc%d0%bd-14/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231206T140000
DTEND;TZID=Europe/Sofia:20231206T153000
DTSTAMP:20260429T164611
CREATED:20231129T113157Z
LAST-MODIFIED:20231129T113339Z
UID:15541-1701871200-1701876600@math.bas.bg
SUMMARY:Национален семинар по стохастика
DESCRIPTION:Поредната сбирка на \nНационалния семинар по стохастика\nще се проведе на 6 декември 2023 г. (сряда) от 14:00 часа в зала 503 на ИМИ – БАН. \nДоклад на тема \nBrownian Motion Conditioned to Spend Limited Time Outside a Bounded Interval – An Extreme Example of Entropic Repulsion\nще изнесе \nDominic Т. Schickentanz (TU Darmstadt). \nАбстракт. We condition a Brownian motion on \(\mathbb{R}_{\ge 0}\) on spending a total of at most \(s>0\) time units outside a bounded interval. We describe the resulting process in terms of an SDE and discuss the surprising result in the context of entropic repulsion. Moreover\, we explicitly determine the exact asymptotic behavior of the probability that a Brownian motion on \([0\,T]\) spends limited time outside a bounded interval\, as \(T\to \infty\). \nThis is joint work with Frank Aurzada (TU Darmstadt) and Martin Kolb (Paderborn Uni)\n 
URL:https://math.bas.bg/event/%d0%bd%d0%b0%d1%86%d0%b8%d0%be%d0%bd%d0%b0%d0%bb%d0%b5%d0%bd-%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bf%d0%be-%d1%81%d1%82%d0%be%d1%85%d0%b0%d1%81%d1%82%d0%b8%d0%ba%d0%b0-39/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%98%D0%BD%D1%81%D1%82%D0%B8%D1%82%D1%83%D1%82%20%D0%BF%D0%BE%20%D0%BC%D0%B0%D1%82%D0%B5%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20%D0%B8%20%D0%B8%D0%BD%D1%84%D0%BE%D1%80%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20-%20%D0%91%D0%90%D0%9D":MAILTO:office@math.bas.bg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Europe/Sofia:20231206T160000
DTEND;TZID=Europe/Sofia:20231206T173000
DTSTAMP:20260429T164611
CREATED:20231130T142439Z
LAST-MODIFIED:20231130T142439Z
UID:15607-1701878400-1701883800@math.bas.bg
SUMMARY:Семинар по геометрия на МЦМН
DESCRIPTION:Следващата сбирка на Семинара по геометрия на МЦМН\nще се проведе в сряда\, 6 декември 2023 г. от 16:00 ч. в зала 403 и онлайн в Zoom: \nДоклад на тема \n\nIntroduction to tropical modifications (II)\nще изнесе Никита Калинин\, Международен център по математически науки (МЦМН – София). \n\nZoom link:\n\nhttps://us02web.zoom.us/j/83740034721?pwd=VnBtcVpGUktscHQ4a09jZkNZTURyZz09
URL:https://math.bas.bg/event/%d1%81%d0%b5%d0%bc%d0%b8%d0%bd%d0%b0%d1%80-%d0%bf%d0%be-%d0%b3%d0%b5%d0%be%d0%bc%d0%b5%d1%82%d1%80%d0%b8%d1%8f-%d0%bd%d0%b0-%d0%bc%d1%86%d0%bc%d0%bd-4/
LOCATION:Институт по математика и информатика – БАН\, Block 8\, 1113 БАН IV км.\, София\, Bulgaria
CATEGORIES:Редовен семинар
ORGANIZER;CN="%D0%98%D0%BD%D1%81%D1%82%D0%B8%D1%82%D1%83%D1%82%20%D0%BF%D0%BE%20%D0%BC%D0%B0%D1%82%D0%B5%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20%D0%B8%20%D0%B8%D0%BD%D1%84%D0%BE%D1%80%D0%BC%D0%B0%D1%82%D0%B8%D0%BA%D0%B0%20-%20%D0%91%D0%90%D0%9D":MAILTO:office@math.bas.bg
END:VEVENT
END:VCALENDAR