Abstract We prove for the first time that knot Floer homology and Khovanov homology can detect non-fibered knots and that HOMFLY homology detects infinitely many knots; these theories were previously known to detect a mere six knots, all fibered. These results rely on our main technical theorem, which gives a complete classification of genus-1 knots in the 3-sphere whose knot Floer homology in the top Alexander grading is 2-dimensional. We discuss applications of this classification to problems in Dehn surgery which are carried out in two sequels. These include a proof that$$0$$-surgery characterizes infinitely many knots, generalizing results of Gabai from his 1987 resolution of the Property R Conjecture. 
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                    This content will become publicly available on August 1, 2026
                            
                            Ranks of matrix factorizations and sheaf cohomology
                        
                    
    
            Buchweitz-Greuel-Schreyer conjectured in 1987 a lower bound on the ranks of matrix factorizations over certain local hypersurface rings [Invent. Math. 88 (1987), pp. 165–182]. We study a graded version of this conjecture, and we show that it implies a novel conjecture concerning the cohomology of sheaves over non-Fano projective hypersurfaces. 
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                            - Award ID(s):
- 2200732
- PAR ID:
- 10616615
- Publisher / Repository:
- AMS
- Date Published:
- Journal Name:
- Proceedings of the American Mathematical Society
- Volume:
- 153
- Issue:
- 794
- ISSN:
- 0002-9939
- Page Range / eLocation ID:
- 3291 to 3301
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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