dorsal/arxiv
View SchemaCasson-Lin's invariant of a knot and Floer homology
| Authors | Weiping Li |
|---|---|
| Categories | |
| ArXiv ID | q-alg/9605036 |
| URL | https://arxiv.org/abs/q-alg/9605036 |
Abstract
A. Casson defined an intersection number invariant which can be roughly thought of as the number of conjugacy classes of irreducible representations of $\pi_1(Y)$ into $SU(2)$ counted with signs, where $Y$ is an oriented integral homology 3-sphere. X.S. Lin defined an similar invariant (signature of a knot) to a braid representative of a knot in $S^3$. In this paper, we give a natural generalization of the Casson-Lin's invariant to be (instead of using the instanton Floer homology) the symplectic Floer homology for the representation space (one singular point) of $\pi_1(S^3 \setminus K)$ into $SU(2)$ with trace-free along all meridians. The symplectic Floer homology of braids is a new invariant of knots and its Euler number of such a symplectic Floer homology is the negative of the Casson-Lin's invariant.
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"abstract": "A. Casson defined an intersection number invariant which can be roughly\nthought of as the number of conjugacy classes of irreducible representations of\n$\\pi_1(Y)$ into $SU(2)$ counted with signs, where $Y$ is an oriented integral\nhomology 3-sphere. X.S. Lin defined an similar invariant (signature of a knot)\nto a braid representative of a knot in $S^3$. In this paper, we give a natural\ngeneralization of the Casson-Lin\u0027s invariant to be (instead of using the\ninstanton Floer homology) the symplectic Floer homology for the representation\nspace (one singular point) of $\\pi_1(S^3 \\setminus K)$ into $SU(2)$ with\ntrace-free along all meridians. The symplectic Floer homology of braids is a\nnew invariant of knots and its Euler number of such a symplectic Floer homology\nis the negative of the Casson-Lin\u0027s invariant.",
"arxiv_id": "q-alg/9605036",
"authors": [
"Weiping Li"
],
"categories": [
"q-alg",
"math.QA"
],
"title": "Casson-Lin\u0027s invariant of a knot and Floer homology",
"url": "https://arxiv.org/abs/q-alg/9605036"
},
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