Computable Legendrian Invariants
نویسنده
چکیده
We establish tools to facilitate the computation and application of the ChekanovEliashberg differential graded algebra (DGA), a Legendrian-isotopy invariant of Legendrian knots in standard contact three-space. More specifically, we reformulate the DGA in terms of front projections, and introduce the characteristic algebra, a new invariant derived from the DGA. We use the characteristic algebra to distinguish between several previously indistinguishable Legendrian knots.
منابع مشابه
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