Crossed modules

التفاصيل البيبلوغرافية
العنوان: Crossed modules
المؤلفون: Huebschmann, Johannes
المصدر: Notices Amer. Math. Soc. 70 (2023), 1802-1813
سنة النشر: 2024
المجموعة: Mathematics
مصطلحات موضوعية: Mathematics - Group Theory, Mathematics - Algebraic Topology, 01A60 12G05 18G45 20J05 57M10
الوصف: This is an overview of the idea of a crossed module. For a group, the triple that consists of the group, its group of automorphisms, and the canonical homomorphism from the group to its group of automorphisms constitutes a crossed module. Crossed modules arise from the identities among the relations of the presentation of a group, from the extension problem for groups and, more generally, in low dimensional topology. Also, the (successful) attempt to extend the idea of a normal extension of commutative fields to the realm of non-commutative algebras leads to crossed modules. Crossed modules appear implicitly in a forgotten paper by A. Turing which in principle settles the extension problem for groups. Crossed modules make perfect sense for Lie algebras.
Comment: 17 pages
نوع الوثيقة: Working Paper
DOI: 10.1090/noti2831
URL الوصول: http://arxiv.org/abs/2403.15900
رقم الأكسشن: edsarx.2403.15900
قاعدة البيانات: arXiv