{ "id": "math/0410275", "version": "v2", "published": "2004-10-11T15:41:47.000Z", "updated": "2005-03-14T15:28:33.000Z", "title": "Palindromes and orderings in Artin groups", "authors": [ "Florian Deloup" ], "comment": "16 pages, 4 figures. Main result extended to Artin groups. simplification of classification of $\\tau$-invariant palindromes in finite Artin groups. Added references", "categories": [ "math.GT", "math.GR" ], "abstract": "The braid group $B_{n}$, endowed with Artin's presentation, admits two distinguished involutions. One is the anti-automorphism ${\\rm{rev}}: B_{n} \\to B_{n}$, $v \\mapsto \\bar{v}$, defined by reading braids in the reverse order (from right to left instead of left to right). Another one is the conjugation $\\tau:x \\mapsto \\Delta^{-1}x \\Delta$ by the generalized half-twist (Garside element). More generally, the involution ${\\rm{rev}}$ is defined for all Artin groups (equipped with Artin's presentation) and the involution $\\tau$ is defined for all Artin groups of finite type. A palindrome is an element invariant under rev. We classify palindromes and palindromes invariant under $\\tau$ in Artin groups of finite type. The tools are elementary rewriting and the construction of explicit left-orderings compatible with rev. Finally, we discuss generalizations to Artin groups of infinite type and Garside groups.", "revisions": [ { "version": "v2", "updated": "2005-03-14T15:28:33.000Z" } ], "analyses": { "subjects": [ "20F36" ], "keywords": [ "artin groups", "artins presentation", "involution", "explicit left-orderings", "palindromes invariant" ], "note": { "typesetting": "TeX", "pages": 16, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2004math.....10275D" } } }