Problems / geometry-topology
geometry-topology / Stable homotopy theory: chromatic homotopy
Hopkins' chromatic splitting conjecture (weak and odd-prime strong forms)
Weak form: for the derived p-completion X=Sp∧, the canonical map Ln−1X→Ln−1LK(n)X has no homotopy retraction at height n=p for every p≥5 and at n=p+1 for every p≥7; the class β1(p−1)2 is a nonzero kernel element (at p=5, β116 in degree 608). Strong form: for p≥5 the map L0LK(3)S→L0LK(2)LK(3)S is nonzero on π−3, so the height-three splitting fails even as an equivalence of E(2)-local spectra. Companions: at n=p=3 the overlap is not in the thick subcategory generated by L0S,L1S,L2S; positively, for p>n+1 the overlap has a 2n-stage filtration with the predicted cofibers (nonsplit), with explicit attachments at height three. Heights below p−1 remain open.