Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Stability constants and the homology of quasi-Banach spaces   We affirmatively solve the main problems posed by Laczkovich and Paulin in
\emph{Stability constants in linear spaces}, Constructive Approximation 34
(2011) 89--106 (do there exist cases in which the second Whitney constant is
finite while the approximation constant is infinite?) and by Cabello and
Castillo in \emph{The long homology sequence for quasi-Banach spaces, with
applications}, Positivity 8 (2004) 379--394 (do there exist Banach spaces $X,Y$
for which $\Ext(X,Y)$ is Hausdorff and non-zero?). In fact, we show that these
two problems are the same.

13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
17
The categories of this paper are: q-fin
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
6
The categories of this paper are: astro-ph