1 Answers
In algebra, given a commutative ring R, the graded-symmetric algebra of a graded R-module M is the quotient of the tensor algebra of M by the ideal I generated by elements of the form:
for homogeneous elements x, y in M of degree |x |, |y |. By construction, a graded-symmetric algebra is graded-commutative; i.e., x y = | x | | y | y x {\displaystyle xy=^{|x||y|}yx} and is universal for this.
In spite of the name, the notion is a common generalization of a symmetric algebra and an exterior algebra: indeed, if V is a R-module, then the graded-symmetric algebra of V with trivial grading is the usual symmetric algebra of V. Similarly, the graded-symmetric algebra of the graded module with V in degree one and zero elsewhere is the exterior algebra of V.