Obstructions to Lagrangian concordance (Q276578)

The authors investigate the question of Lagrangian concordance between Legendrian knots in \(\mathbb R^{3}\). They give obstructions to a concordance through \(A_{(2)}\) compatibility and normal ruling. They discuss decomposable concordances and discuss some obstructions to their occurrence. They also show restrictions on knots to have concordances to and from an unknot and construct an infinite family of knots with nonreversible concordances from the unknot. Finally they use their obstructions to present knots with up to 14 crossings that have Legendrian representatives which have concordances with the unknot.