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  "body": "\n## Summary\n\nKnot Floer homology is an invariant of [[knots|QYEAZTYGPT]] in $3$-manifolds built from [[Heegaard Floer homology|2WJJBN2T5P]].\nIt was introduced by Ozsváth and Szabó, and independently by Rasmussen.\nFor a knot in $S^3$ it is a bigraded vector space whose graded Euler characteristic is the [[Alexander polynomial|JKA25KDPQP]].\nIt detects the Seifert genus of a knot and whether the knot is fibered.\n\n## Explanations\n\n### L1 human\n\nKnot Floer homology describes a knot by a finite list of vector spaces, arranged in a grid by two gradings.\nAdding up their dimensions with suitable signs recovers the Alexander polynomial.\nBut the list knows more: the highest row that is not zero tells you the least genus of a surface bounded by the knot.\nIt comes from counting certain holomorphic disks, a technique from symplectic geometry.\n",
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