Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Filtering germs: Groupoids associated to inverse semigroups   We investigate various groupoids associated to an arbitrary inverse semigroup
with zero. We show that the groupoid of filters with respect to the natural
partial order is isomorphic to the groupoid of germs arising from the standard
action of the inverse semigroup on the space of idempotent filters. We also
investigate the restriction of this isomorphism to the groupoid of tight
filters and to the groupoid of ultrafilters.

11
The categories of this paper are: hep-lat
34
The categories of this paper are: chem-ph
24
The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
3
The categories of this paper are: physics
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
20
The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph