{{menu|Events|Special Lecture May 2012}}

Special lecture by Ostap Chervak on 2012-05-15, 2 - 3 pm (during Professor Friedman's normal lecture time) 
in the [/Floor_plan.html lecture room] of the KGRC.

== Abstract ==
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Higson corona is a natural object in coarse geometry, being a coarse
analogue of Stone-Cech compactification. As a consequence to
Parovicenko theorems, I. Protasov proved that under CH Higson coronas
of all asymptotically zero-dimensional metric spaces are homeomorphic
and wondered if this result remains true in ZFC. We answer negatively
on this question and prove that under some set-theoretic assumptions
($\mathfrak u<\mathfrak d$ or MA + OCA) Higson corona of anti-Cantor
set is not homeomorphic to Higson corona of divergent sequence
$\{n^2\}_{n\in\mathbb{N}}$.
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