An upper bound for the representation dimension of group algebras with elementary abelian Sylow p-subgroups

Abstract

In this article, we present an upper bound on the representation dimension of the group algebra of a group with an elementary abelian Sylow p-subgroup. Specifically, if k is a field of characteristic p and G is a group with elementary abelian Sylow p-subgroup P, we prove that the representation dimension of kG is bounded above by the order of P. Key to proving this theorem is the separable equivalence between the two algebras and some nice properties of Mackey decomposition.     

On a class of coupled Hamiltonian operators and their integrable hierarchies with two potentials

We discuss at first in this paper the Gauge equivalence among several u‐linear Hamiltonian operators and present explicitly the associated Gauge transformation of Bäcklund type among them. We then establish the sufficient and necessary conditions for the linear superposition of the discussed u‐linear operators and matrix differential operators with constant coefficients of arbitrary order to be Hamiltonian, which interestingly shows that the resulting Hamiltonian operators survive only up to the third differential order. Finally, we explore a few illustrative examples of integrable hierarchies from Hamiltonian pairs embedded in the resulting Hamiltonian operators.     

状态函数的性质等价性的数学证明

将状态函数的性质用数学表达式表达，严格地证明了状态函数性质的3个数学表达式是等价的，与麦克斯韦关系式也是等价的，从而在数学上证明了状态函数的性质是等价的，应用状态函数的性质解决实际问题，可以使问题极大地简化。     

保持两个等价关系的变换半群的Green关系

Let Tx be the full transformation semigroup on a set X. For a non-trivial equivalence F on X, let
TF（X） = {f ∈ Tx ： arbieary （x, y） ∈ F, （f（x）,f（y）） ∈ F}.
Then TF（X） is a subsemigroup of Tx. Let E be another equivalence on X and TFE（X） = TF（X） ∩ TE（X）. In this paper, under the assumption that the two equivalences F and E are comparable and E lohtain in F, we describe the regular elements and characterize Green＇s relations for the semigroup TFE（X）.     

Spectrum of orientifold QCD in the strong coupling and hopping expansion approximation

We use the strong coupling and hopping parameter expansions to calculate the pion and rho meson masses for lattice Yang–Mills gauge theories with fermions in irreducible two-index representations, namely the adjoint, symmetric and antisymmetric. The results are found to be consistent with orientifold planar equivalence, and leading order 1/Nc$1/N_c$ corrections are calculated in the lattice phase. An estimate of the critical bare mass, for which the pion is massless, is obtained as a function of the bare coupling. A comparison to data from the two-flavour SU(2)$\mathit{SU}(2)$ theory with adjoint fermions gives evidence for a bulk phase transition at βc∼2${\beta }_c\sim 2$, separating a pure lattice phase from a phase smoothly connected to the continuum.     

Nonlinear Perturbations for Linear Nonautonomous Impulsive Differential Equations and Nonuniform $(h,k,\mu,\nu)$-dichotomy

We explore nonlinear perturbations of a flow generated by a linear nonautonomous impulsive differential equation $x''=A(t)x,t\neq\tau_i,\Delta x|_{t=\tau_i}=B_ix(\tau_i),~ i \in \Z$ in Banach spaces. Here we assume that the linear nonautonomous impulsive equation admits a more general dichotomy on $\R$ called the nonuniform $(h,k,\mu,\nu)$-dichotomy, which extends the existing uniform or nonuniform dichotomies and is related to the theory of nonuniform hyperbolicity. Under nonlinear perturbations, we establish a new version of the Grobman-Hartman theorem and construct stable and unstable invariant manifolds for nonlinear nonautonomous impulsive differential equations $x''=A(t)x+f(t,x)$, $t\neq \tau_i, \Delta x|_{t=\tau_i}=B_ix(\tau_i)+g_i(x(\tau_i)),i \in \Z$ with the help of nonuniform $(h,k,\mu,\nu)$-dichotomies.     

Elementary equivalence of rings with finitely generated additive groups

We give algebraic characterizations of elementary equivalence between rings with finitely generated additive groups. They are similar to those previously obtained for finitely generated nilpotent groups. Here, the rings are not supposed associative, commutative or unitary.     

A note on the Glauberman correspondence

In this paper, we will investigate the Glauberman-Watanabe correspondence between the characters and blocks. Motivated by the work of Puig and Zhou [10 Puig, L., Zhou, Y. (2012). Glauberman correspondents and extensions of nilpotent block algebras. J. London Math. Soc. (2) 85809–837.[Crossref] , [Google Scholar]] which is about the extension of a nilpotent block and its Glauberman correspondent, we will modify the basic Morita equivalence obtained in their work and get a new equivalence such that the correspondence between characters induced by this equivalence coincides with the Glauberman correspondence under the situation that the block is a p-extension of a nilpotent block.     

Invariant characterization of scalar third‐order ODEs that admit the maximal point symmetry Lie algebra

The Cartan equivalence method is used to deduce an invariant characterization of the scalar third‐order ordinary differential equation , which admits the maximal 7‐dimensional point symmetry Lie algebra. The method provides auxiliary functions that can be used to efficiently obtain the point transformation that does the reduction to the simplest linear equation . Moreover, examples are given to illustrate the method.