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<p> Tuesday, 9 December 2025 - 10:00 to 11:30 <br>
Place: IM, Konírna, ground floor, front building</p>
<p> Speaker: Julia Ścisłowska, University of Warsaw<br>
Title: Extraordinary properties of Suslinean chainable continua</p>
<p> Abstract <br>
</p>
<p class="ql-align-justify">During my talk I will introduce
ultrafilter orders on chainable continua and I will present
known results in this topic. In particular, I will mention some
ideas how we can express the “level of complexity” of a given
chainable continuum in the language of ultrafilter orders. It
will turn out that from a particular viewpoint Suslinean
chainable continua are relatively simple spaces. To illustrate
this claim, I will show some ideas related to a new result
stating that any Suslinean chainable continuum equipped with any
ultrafilter order has the order type of an interval. Another new
result, which I will discuss, states that for Suslinean
chainable continua, any ultrafilter order is both of type F_σ
and G_δ.</p>
<p class="ql-align-justify">This is a joint work with Witold
Marciszewski and Benjamin Vejnar, preprint is available at: <a
href="https://arxiv.org/abs/2510.14577"
rel="noopener noreferrer" target="_blank"
style="color: rgb(5, 99, 193);" class="moz-txt-link-freetext">https://arxiv.org/abs/2510.14577</a>.</p>
<br>
<p> For more information see the seminar web page at <br>
<a href="https://www.math.cas.cz/index.php/events/seminar/6"
target="_blank"
data-saferedirecturl="https://www.google.com/url?q=https://www.math.cas.cz/index.php/events/seminar/6&source=gmail&ust=1764662973385000&usg=AOvVaw0SGQojlwJ4tR6LGexhGJ52">https://www.math.cas.cz/index.<wbr>php/events/seminar/6</a>
</p>
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