The NOP conjecture on fixed points for finitely generated torsion groups

Let $G$ be a finitely generated group acting by isometries on a finite-dimensional CAT(0) complex. NOP conjecture. If the action has no global fixed point, then $G$ contains an element of infinite order. Equivalently, every finitely generated torsion group acting on a finite-dimensional CAT(0) complex has a global fixed point. This conjecture concerns whether finite-dimensional CAT(0) geometry can support fixed-point-free actions of finitely generated torsion groups; the source presents it as a conjecture stated in earlier work, with the surrounding discussion describing related partial results and infinite-dimensional counterexamples.