{ "id": "1805.02563", "version": "v1", "published": "2018-05-07T15:14:40.000Z", "updated": "2018-05-07T15:14:40.000Z", "title": "A comparison of classes in the Johnson cokernels of the mapping class groups of surfaces", "authors": [ "Naoya Enomoto", "Yusuke Kuno", "Takao Satoh" ], "comment": "17 pages", "categories": [ "math.GT", "math.AT", "math.RT" ], "abstract": "In [ES2], the first and the third authors introduced new classes in the Johnson cokernels of the mapping class groups of surfaces by a representation theoretic approach based on some previous results for the Johnson cokernels of the automorphism groups of free groups. On the other hand, in [KK1], Kawazumi and the second author introduced another type of classes by a topological consideration of self-intersections of curves on a surface. In this paper, we show that the classes found in [KK1] are contained in the classes found in [ES2] in a stable range. Furthermore, we prove that the anti-Morita obstructions $[1^{4m+1}]$ for $m \\ge 1$ obtained in [ES2] and a hook-type component $[3,1^5]$ detected in [EE] appear in their gap.", "revisions": [ { "version": "v1", "updated": "2018-05-07T15:14:40.000Z" } ], "analyses": { "keywords": [ "mapping class groups", "johnson cokernels", "comparison", "representation theoretic approach", "third authors" ], "note": { "typesetting": "TeX", "pages": 17, "language": "en", "license": "arXiv", "status": "editable" } } }