Repository logo

Department of Mathematics

Permanent URI for this community

https://hdl.handle.net/10217/100468
These digital collections include faculty/student publications, theses, and dissertations from the Department of Mathematics.

Browse

Browsing Department of Mathematics by Subject "algebra"

Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    A simplicial homotopy group model for K2 of a ring
    (Colorado State University. Libraries, 2010) Whitfield, JaDon Saeed, author; Duflot, Jeanne, advisor; Miranda, Rick, committee member; Achter, Jeffrey D., committee member; Gelfand, Martin Paul, committee member
    We construct an isomorphism between the group K2(R) from classical, algebraic K-Theory for a ring R and a simplicial homotopy group constructed using simplicial homotopy theory based on that same ring R. First I describe the basic aspects of simplicial homotopy theory. Special attention is paid to the use of category theory, which will be applied to the construction of a simplicial set. K-Theory for K0(R), K1(R) and K2(R) is then described before we set to work describing explicitly the nature of isomorphisms for K0(R) and K1(R) based on previous work. After introducing some theory related to K-Theory, some considerations and corrections on previous work motivate more new theory that helps the isomorphism with K2(R). Such theory is developed, mainly with regards to finitely generated projective modules over R and then elementary matrices with entries from R, culminating in the description of the Steinberg Relations that are central to the understanding of K2(R) in terms of homotopy classes. We then use new considerations on the previous work to show that a map whose image is constructed through this article is an isomorphism since it is the composition of isomorphisms.
  • Thumbnail Image
    ItemOpen Access
    Asymptotic enumeration of matrix groups
    (Colorado State University. Libraries, 2018) Tyburski, Brady A., author; Wilson, James B., advisor; Adams, Henry, committee member; Pries, Rachel, committee member; Wilson, Jesse W., committee member
    We prove that the general linear group GLd(pe) has between pd4e/64-O(d2) and pd4e2·log2p distinct isomorphism types of subgroups. The upper bound is obtained by elementary counting methods, where as the lower bound is found by counting the number of isomorphism types of subgroups of the generalized Heisenberg group. To count these subgroups, we use nuclei of a bilinear map alongside versor products - a division analog of the tensor product.