منابع مشابه
Root systems and generalized associahedra
Contents Root systems and generalized associahedra 1 Root systems and generalized associahedra 3 Lecture 1. Reflections and roots 5 1.1. The pentagon recurrence 5 1.2. Reflection groups 6 1.3. Symmetries of regular polytopes 8 1.4. Root systems 11 1.5. Root systems of types A, B, C, and D 13 Lecture 2. Dynkin diagrams and Coxeter groups 15 2.1. Finite type classification 15 2.2. Coxeter groups ...
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We find all the inequivalent simple root systems for the complex reflection groups G12, G24, G25 and G26. Then we give all the non-congruent essential presentations of these groups by generators and relations. The methed used in the paper is applicable to any finite (complex) reflection groups. Introduction. Shephard and Todd classified all the finite complex reflection groups in paper [5]. Lat...
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Graphs which generalize the simple or aane Dynkin diagrams are introduced. Each diagram deenes a bilinear form on a root system and thus a reeection group. We present some properties of these groups and of their natural \Coxeter element". The folding of these graphs and groups is also discussed, using the theory of C-algebras. Abstract Graphs which generalize the simple or aane Dynkin diagrams ...
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متن کاملGeneralized Dynkin diagrams and root systems and their folding
Graphs which generalize the simple or affine Dynkin diagrams are introduced. Each diagram defines a bilinear form on a root system and thus a reflection group. We present some properties of these groups and of their natural “Coxeter element”. The folding of these graphs and groups is also discussed, using the theory of C-algebras.
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ژورنال
عنوان ژورنال: Journal of Algebra
سال: 2017
ISSN: 0021-8693
DOI: 10.1016/j.jalgebra.2017.08.010