The General PBW Property

Generalized nil-Coxeter algebras, cocommutative algebras, and the PBW property

Poincare-Birkhoff-Witt (PBW) Theorems have attracted significant attention since the work of Drinfeld (1986), Lusztig (1989), and Etingof-Ginzburg (2002) on deformations of skew group algebras $H \ltimes {\rm Sym}(V)$, as well as for other cocommutative Hopf algebras $H$. In this paper we show that such PBW theorems do not require the full Hopf algebra structure, by working in the more general setting of a "cocommutative algebra", which involves a coproduct but not a counit or antipode. Special cases include infinitesimal Hecke algebras, as well as symplectic reflection algebras, rational Cher…

Lengths of Finite Dimensional Representations of PBW Algebras

We present a proof of an upper bound for the lengths of finite dimensional representations of algebras obeying a modified PBW property, including Lie algebras and quantum groups. The sharpness of the bound is proved and discussed.

PBW property for associative universal enveloping algebras over an operad

Given a symmetric operad $\mathcal{P}$ and a $\mathcal{P}$-algebra $V$, the associative universal enveloping algebra ${\mathsf{U}_{\mathcal{P}}}$ is an associative algebra whose category of modules is isomorphic to the abelian category of $V$-modules. We study the notion of PBW property for universal enveloping algebras over an operad. In case $\mathcal{P}$ is Koszul a criterion for the PBW property is found. A necessary condition on the Hilbert series for $\mathcal{P}$ is discovered. Moreover, given any symmetric operad $\mathcal{P}$, together with a Gröbner basis $G$, a condition is given in…

变形论与霍普夫作用在科兹尔代数上的作用

Deformation Theory and Hopf Actions on Koszul Algebras

研究非交换代数上格雷德变形与PBW变形的纤维结构，聚焦霍普夫代数作用于二次代数的霍普夫-科兹尔海德代数，通过扭转张量积的亚历山大-惠特尼和埃利恩伯格-齐贝尔映射转换同调信息。