Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the Linking Principle   We give a linking theorem that strengthens and unifies some many minimax
theorems including Ambrosetti-Rabinowitz ``mountain pass theorem'', Rabinowitz
``multidimensional mountain pass theorem'', Rabinowitz ``saddle point theorem''
and Silva's variants of these results.
  We focus our attention especially on ``the limiting case'', known to be true
for the mountain pass principle, where some information on the location of the
critical points is given. Two forms of this theorem are given: the first one is
established via a deformation lemma and we use Ekeland's variational principle
to get the second one.

18
The categories of this paper are: econ
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
12
The categories of this paper are: nucl-th
0
The categories of this paper are: hep-ph
32
The categories of this paper are: atom-ph
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat