Ng, Lenhard L. Computable Legendrian invariants. (English) Zbl 1032.53070 Topology 42, No. 1, 55-82 (2003). In the paper under review the author establishes tools to faciliate the computation and application of the Chekanov-Eliashberg differential graded algebra (DGA), a Legendrian-isotopy invariant of Legendrian knots and links in standard contact three space. More specifically, he reformulates the DGA in terms of front projections and introduces the characteristic algebra, a new invariant derived from the DGA. He uses his own techniques to distinguish between several previously indistinguishable Legendrian knots and links. Reviewer: R.Iordanescu (Bucureşti) Cited in 2 ReviewsCited in 48 Documents MSC: 53D12 Lagrangian submanifolds; Maslov index 57R17 Symplectic and contact topology in high or arbitrary dimension Keywords:Legendrian knot invariant; Front projection; Differential graded algebra PDFBibTeX XMLCite \textit{L. L. Ng}, Topology 42, No. 1, 55--82 (2003; Zbl 1032.53070) Full Text: DOI arXiv