Let $latex U$ is a set. A filter (on $latex U$) $latex \mathcal{F}$ is by definition a non-empty set of subsets of $latex U$ such that $latex A,B\in\mathcal{F} \Leftrightarrow A\cap B\in\mathcal{F}$. Note that unlike some other authors I do not require $latex…

read moreFor filters on sets defined equivalence relation being isomorphic. Posed some open problems like this: are every two nontrivial ultrafilters isomorphic?

read moreA mathematician has said me that he cannot understand my writings because I introduce new terms without examples before. Because of this I added to my article Funcoids and Reloids (PDF) new subsection Informal introduction into funcoids. Hopefully now it is understandable….

read moreI abandoned my old blogs at my own site and moved to WordPress.com. This is my new math blog. Here I will tell about my math research.

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