На 15 юли 2025 г. от 13:00 часа в зала 403 на ИМИ-БАН ще се проведе съвместно заседание на Общия семинар на секция "Анализ, геометрия и топология" и Международния център по математически науки (ICMS-Sofia). Доклад на тема: Weak Metric Structures on Generalized Riemannian Manifolds ще изнесе Milan Zlatanovic, University of Niš, Serbia. Резюме. Linear connections with torsion are important in the study of generalized Riemannian manifolds (M , G=g+F ), where the symmetric part g of G is a non-degenerate (0,2)-tensor and F is the skew-symmetric part. Some space-time models in theoretical physics are based on (M, G=g+F) , where F is defined using a complex structure. In the lecture, we will show more general models, where F has constant rank [...]

Съвместна сбирка на семинара на МЦМН и семинара "Анализ, геометрия и топология" в ИМИ, София, ще се проведе идния вторник, с доклад на Elia Fusi, както следва. Вторник, 22-ри юли, 13:00 часа, зала 403 на ИМИ-БАН. Elia Fusi, University of Torino: Special metrics in hypercomplex geometry Abstract:The existence of special hyperHermitian metrics plays an important role in the study of hypercomplex manifolds. In this talk, after a brief overview of the basic definitions in hypercomplex Geometry, we will discuss two of the main types of special metrics in the hypercomplex setting: quaternionic Gauduchon and strong HKT metrics. First of all, we will discuss sufficient and equivalent conditions for a quaternionic Gauduchon metric to exist.  Afterwards, we will show that strong HKT and balanced hyperHermitian metrics [...]

Семинар "Анализ, геометрия и топология" Вторник, 22 юли 2025 г., 13:00 ч., зала 403 на ИМИ - БАН. Elia Fusi, University of Torino. Special metrics in hypercomplex geometry Резюме: The existence of special hyperHermitian metrics plays an important role in the study of hypercomplex manifolds. In this talk, after a brief overview of the basic definitions in hypercomplex Geometry, we will discuss two of the main types of special metrics in the hypercomplex setting: quaternionic Gauduchon and strong HKT metrics. First of all, we will discuss sufficient and equivalent conditions for a quaternionic Gauduchon metric to exist.  Afterwards, we will show that strong HKT and balanced hyperHermitian metrics cannot coexist on a compact non-hyperKähler manifold, proving a particular instance of the Fino-Vezzoni conjecture. Finally, [...]

Семинар "Анализ, геометрия и топология" Вторник, 29 юли 2025 г., 13:00 ч., зала 403 на ИМИ - БАН. Speaker: Asia Mainenti, IMI and ICMS, Sofia Hodge-Riemann balanced structures on non-Kähler manifolds Резюме:  A Hodge-Riemann balanced structure on a complex manifold is the datum of a balanced metric whose (n-1)-th power can be decomposed into the wedge product of two differential forms, satisfying the classical Hodge-Riemann bilinear relations. Such structures were introduced by X. Chen and R. Wentworth, to generalize the nonabelian Hodge correspondence to non-Kähler Hermitian metrics. However, there are no known examples of Hodge-Riemann balanced structures on non-Kähler manifolds. The aim of this talk is to address this lack of examples, highlighting the relation with p-Kähler structures and discuss some obstruction results in [...]

Следващото заседание на семинара на МЦМН ще се състои във вторник, 2 декември 2025 г. Доклади ще изнесат Рой Маген от МЦМН и Ливиу Орнеа от Букурещския университет, като вторият доклад е в рамките на съвместно заседание със семинара на секция "Анализ, Геометрия и Топология". Програмата е следната. ICMS Seminar and AGT Seminar Tuesday, December 2nd, room 403 IMI-BAS. 13:00 -- Roy Magen (ICMS, IMI-BAS)  Flavours of homotopy theory 14:00 -- Liviu Ornea (University of Bucarest)  Distinguished non-Kähler metrics on compact complex manifolds Abstract (Magen):    In this talk we will consider different flavours of homotopy theory for different types of geometric contexts. First we will recall the usual definitions of the homotopy category, and equivariant homotopy categories, and we will show how we can think of these in [...]