Cohomology ring of tree braid groups and exterior face rings

نویسندگان

چکیده

For a tree T T and positive integer alttext="n"> n encoding="application/x-tex">n , let B Subscript n Baseline upper B encoding="application/x-tex">B_nT denote the -strand braid group on . We use discrete Morse theory techniques to show that cohomology ring H Superscript asterisk left-parenthesis T right-parenthesis"> H ? ( stretchy="false">) encoding="application/x-tex">H^*(B_nT) is encoded by an explicit abstract simplicial complex K K encoding="application/x-tex">K_nT measures -local interactions among essential vertices of that, in many cases (for instance when binary tree), exterior face determined

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ژورنال

عنوان ژورنال: Transactions of the American Mathematical Society

سال: 2022

ISSN: ['2330-0000']

DOI: https://doi.org/10.1090/btran/131