Seminarium 23.05.2024

**Noncontractive Iterated Function Systems which have attractors**

*Nina Snigireva*

(University of Galway)

(University of Galway)

In this talk we will discuss the existence of attractors and semiattractors for noncontractive Iterated Function Systems (IFSs). While there are noncontractive IFSs which have attractors, to date there was no example of an IFS in Euclidean space which is noncontractive under any remetrization and has an attractor. We will introduce L-expansive IFSs and show that such systems provide examples of noncontractive IFSs in Euclidean space with attractors.

This is joint work with K. Lesniak, F. Strobin and A. Vince

Seminarium 06.06.2024

*Michał Pawlikowski*

(Institute of Mathematics, Lodz University of Technology)

(Institute of Mathematics, Lodz University of Technology)

Seminarium 13.06.2024

*Natalia Maślany*

Seminarium 20.06.2024

*Tomasz Żuchowski*

(Uniwersytet Wrocławski)

(Uniwersytet Wrocławski)

Seminarium 27.06.2024

**A possible generalization of the determinant**

*Francesco Giacosa*

(Instytut Fizyki)

(Instytut Fizyki)

The use of symmetries is an important tool in theoretical physics, since it strongly constrains the interaction types among particles. Chiral symmetry refers to a certain symmetry that, mathematically, involves two distinct SU(3) groups and is commonly applied to study mesons (composite particles made of a quark and an antiquark, such as pions). Objects of two types are constructed: those that involve the traces of matrices, and those that involve the determinant. Both of them turn out to be 'chirally invariant'.

In the recent work PhysRevD.109.L071502, a certain extension of the determinant has been put forward. This extension reduces to the usual determinant if specific conditions are met, but is more general and appears quite naturally when studying interactions among mesons. Its definition and its properties, as well as possible connections to various other extensions of the determinant, shall be discussed.