The \(P\)-ideal linking concept in critical point theory. Non equivariant case (Q1261617)

The author [An. Acad. Bras. Ciênc. 61, No. 2, 119-128 (1989; Zbl 0702.58016)] introduced and studied the \(P\)-ideal index theory. In this paper, using the numerical-valued cohomological index given by \textit{E. Faddell} and \textit{S. Husseini} [Adv. Math. 64, No. 1, 1-31 (1987; Zbl 0619.58012)], a linking concept via this theory is developed. Some computational examples of \(P\)-ideal linking between two sets \(A\) and \(B\) as well as a general abstract version of Shujie Li's three critical point theorem are also included.