Umbral moonshine and the Niemeier lattices
Umbral moonshine and the Niemeier lattices
复制标题
本影月光和尼迈尔晶格
DOI:
10.1186/2197-9847-1-3
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发表时间:
2013
影响因子:
1.2
通讯作者:
Jeffrey A. Harvey
中科院分区:
文献类型:
--
作者:
Miranda C. N. Cheng;John FR Duncan;Jeffrey A. Harvey
In this paper, we relate umbral moonshine to the Niemeier lattices - the 23 even unimodular positive-definite lattices of rank 24 with non-trivial root systems. To each Niemeier lattice, we attach a finite group by considering a naturally defined quotient of the lattice automorphism group, and for each conjugacy class of each of these groups, we identify a vector-valued mock modular form whose components coincide with mock theta functions of Ramanujan in many cases. This leads to the umbral moonshine conjecture, stating that an infinite-dimensional module is assigned to each of the Niemeier lattices in such a way that the associated graded trace functions are mock modular forms of a distinguished nature. These constructions and conjectures extend those of our earlier paper and in particular include the Mathieu moonshine observed by Eguchi, Ooguri and Tachikawa as a special case. Our analysis also highlights a correspondence between genus zero groups and Niemeier lattices. As a part of this relation, we recognise the Coxeter numbers of Niemeier root systems with a type A component as exactly those levels for which the corresponding classical modular curve has genus zero.AMS subject classification11F22; 11F37; 11F46; 11F50; 20C34; 20C35