“…In [6], Cohen, Jones, and Segal proposed the problem of lifting Floer homology to a Floer spectrum or pro-spectrum, in the sense of stable homotopy theory. Since then, stable homotopy refinements of Floer homology have been constructed in Seiberg-Witten theory [19,12,36] and symplectic geometry [7,15,1]. In a similar vein, there is a lift of Khovanov homology to a stable homotopy type [18,17].…”