For any set representation (permutation representation) of the symmetric group $S_n$, we give combinatorial interpretation for coefficients of its Frobenius character expanded in the basis of monomial symmetric functions.
Characters of symmetric groups in terms of free cumulants and Frobenius coordinates
自由累积量是Young图形状的良好而有用的泛函,特别是它们给出了对称群S(n)在极限n \to \infty中的规范特征标的渐近性.给出了对称群的正规特征标用自由累积量表示的一个显式组合公式。我们也用Frobenius坐标来表示字符。我们的公式涉及到计算给定置换的某些因子分解。主要工具是斯坦利多项式,它给出了多矩形杨图上的字符值。简历自由累积量是函数的可积函数,特别是在\to \infty中对称群S(n)的特征正规化的渐近性。我们给出了一个明确的组合公式,用于自由累积量基础上对称组的标准化特征。我们将以弗罗贝纽斯的坐标为基础来检验这些特征。Nos formules font intervenir le nombre de certaines factorisations d'une permutation donnée.主要是斯坦利的多项式族,它具有杨的多矩形曲线上的特征值。
Gendo-Frobenius algebras are a common generalisation of Frobenius algebras and of gendo-symmetric algebras. A comultiplication is constructed for gendo-Frobenius algebras, which specialises to the known comultiplications on Frobenius and on gendo-symmetric algebras. In addition, Frobenius algebras are shown to be precisely those gendo-Frobenius algebras that have a counit compatible with this comultiplication. Moreover, a new characterisation of gendo-Frobenius algebras is given. This new characterisation is a key for constructing the comultiplication of gendo-Frobenius algebras.
We provide a new virtual description of the symmetric group action on the cohomology of ordered configuration space on SU_2 up to translations. We use this formula to prove the Moseley-Proudfoot-Young conjecture. As a consequence we obtain the graded Frobenius character of the Orlik-Terao algebra of type A_n.
Twisted Burnside-Frobenius theory for discrete groups
对于包括多环和多项式增长群在内的广泛的一类群,证明了自同构f的Reidemeister数等于酉对偶上诱导映射f^的有限维不动点的个数,如果这些个数之一是有限的.这个定理是经典的Burnside-Frobenius定理到无限群的自然推广。这个定理在拓扑动力学中也有重要的结果,在某种意义上是对J. P. Serre。本文所取得的主要技术成果为今后的进一步研究提供了工具。
The representation theory of finite groups began with Frobenius's factorization of Dedekind's group determinant. In this paper, we consider the case of the semigroup determinant. The semigroup determinant is nonzero if and only if the complex semigroup algebra is Frobenius, and so our results include applications to the study of Frobenius semigroup algebras. We explicitly factor the semigroup determinant for commutative semigroups and inverse semigroups. We recover the Wilf-Lindström factorization of the semigroup determinant of a meet semilattice and Wood's factorization for a finite commutat…
Let $G_k$ be a connected reductive algebraic group over an algebraically closed field $k$ of characteristic $\neq 2$. Let $K_k \subset G_k$ be a quasi-split symmetric subgroup of $G_k$ with respect to an involution $θ_k$ of $G_k$. The classification of such involutions is independent of the characteristic of $k$ (provided not $2$). We first construct a closed subgroup scheme $\mathbf{G}^\imath$ of the Chevalley group scheme $\mathbf{G}$ over $\mathbb{Z}$. The pair $(\mathbf{G}, \mathbf{G}^\imath)$ parameterizes symmetric pairs of the given type over any algebraically closed field of characteri…
We develop a theory of Frobenius functors for symmetric tensor categories (STC) $\mathcal{C}$ over a field $\bf k$ of characteristic $p$, and give its applications to classification of such categories. Namely, we define a twisted-linear symmetric monoidal functor $F: \mathcal{C}\to \mathcal{C}\boxtimes {\rm Ver}_p$, where ${\rm Ver}_p$ is the Verlinde category (the semisimplification of ${\rm Rep}_{\bf k}(\mathbb{Z}/p)$). This generalizes the usual Frobenius twist functor in modular representation theory and also one defined in arXiv:1503.01492, where it is used to show that if $\mathcal{C}$ i…