Plethora of cluster structures on $GL_n$
Plethora of cluster structures on $GL_n$
复制标题
$GL_n$ 上有过多的簇结构
DOI:
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发表时间:
2019
期刊:
影响因子:
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通讯作者:
A. Vainshtein
中科院分区:
文献类型:
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作者:
M. Gekhtman;M. Shapiro;A. Vainshtein
We continue the study of multiple cluster structures in the rings of regular functions on $GL_n$, $SL_n$ and $operatorname{Mat}_n$ that are compatible with Poisson-Lie and Poisson-homogeneous structures. According to our initial conjecture, each class in the Belavin-Drinfeld classification of Poisson--Lie structures on a semisimple complex group $mathcal G$ corresponds to a cluster structure in $mathcal O(mathcal G)$. Here we prove this conjecture for a large subset of Belavin-Drinfeld (BD) data of $A_n$ type, which includes all the previously known examples. Namely, we subdivide all possible $A_n$ type BD data into oriented and non-oriented kinds. In the oriented case, we single out BD data satisfying a certain combinatorial condition that we call aperiodicity and prove that for any BD data of this kind there exists a regular cluster structure compatible with the corresponding Poisson-Lie bracket. In fact, we extend the aperiodicity condition to pairs of oriented BD data and prove a more general result that establishes an existence of a regular cluster structure on $SL_n$ compatible with a Poisson bracket homogeneous with respect to the right and left action of two copies of $SL_n$ equipped with two different Poisson-Lie brackets. If the aperiodicity condition is not satisfied, a compatible cluster structure has to be replaced with a generalized cluster structure. We will address this situation in future publications.