Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Combinatorial and model-theoretical principles related to regularity of
  ultrafilters and compactness of topological spaces. II   We find many conditions equivalent to the model-theoretical property $\lambda
\stackrel{\kappa}{\Rightarrow} \mu$ introduced in [L1].
  Our conditions involve uniformity of ultrafilters, compactness properties of
products of topological spaces and the existence of certain infinite matrices.

3
The categories of this paper are: physics
16
The categories of this paper are: stat
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
10
The categories of this paper are: q-bio
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol