Daria Michalik

Daria Michalik: Blocking properties of the diagonal in Cartesian product

Tuesday, November 15, 2022 17:00

Location: room C11-3.11

Speaker:
Daria Michalik (Jan Kochanowski University in Kielce)

Title: Blocking properties of the diagonal in Cartesian product

Abstract: In [1], the authors present six kinds of blocking properties for points in continua. We can consider the same properties for subcontinua. During my talk I will present some results concerning the blocking properties of the diagonal in Cartesian product. Among others, I will show a new characterisation of the interval.

[1] J. Bobok, P. Pyrih and B. Vejnar, Non-cut, shore and non-block points in continua, Glas. Mat. Ser. III 51 (71) (2016), 237–253.

Daria Michalik: Symmetric products as cones

Tuesday, January 8, 2019 17:15

Room: D1-215

Speaker:
Daria Michalik

Title: Symmetric products as cones

Abstract. (join work with Alejandro Illanes and Veronica Martinez-de-la-Vega)

For a continuum \(X\), let \(F_n(X)\) be the hyperspace of all nonempty subsets of \(X\)with at most \(n\)-points. The space \(F_n(X)\) is called the n'th-symmetric product.

In [1] it was proved that if \(X\)is a cone, then its hyperspace \(F_n(X)\) is also a cone.

During my talk I will discuss the converse problem. I will prove that if \(X\)is a locally connected curve, then the following conditions are equivalent:

  1. \(X\)is a cone,
  2. \(F_n(X)\) is a cone for some \(n\ge 2\),
  3. \(F_n(X)\) is a cone for each \(n\ge 2\).

[1] A. Illanes, V. Martinez-de-la-Vega, Symmetric products as cones, Topology Appl. 228 (2017), 36–46.

Daria Michalik: Degree of homogeneity of connes over locally connected curves

Tuesday, November 22, 2016 17:15

Room: D1-215

Speaker:
Daria Michalik

Title: Degree of homogeneity of connes over locally connected curves

Abstract. \(\mathcal{H}(X)\) denotes the group of self-homeomorphisms of \(X\). An orbit of a point \(x_0\) in \(X\)is the set: \(\mathcal{O}_X(x_0) = \{h(x_0) : h\in\mathcal{H}(X)\}.\)

\(X\) is \(1/n\)-homogeneous if \(X\) has exactly \(n\) orbits. In such a case we say that the degree of homogeneity of \(X\) equals \(n\). P. Pellicer Covarrubias, A. Santiago-Santos calculated the degree of homogeneity of connes over local dendrites depending on the degree of homogeneity of their bases. We will generalize above result on connes over locally connected curves.