Ring $R_{ 142 }$

Kaplansky's right-not-left hereditary ring

Description:

Let $k$ be a countable field and $C$ be the ring of $k$ linear transformations of a countably infinite dimensional $k$ vector space. Let $S$ be the socle of $C$, which is the unique nontrivial ideal. Let $B$ be the subring of $C$ generated by $S$ and the identity of $C$. The required ring is $B\otimes_kB$

Keywords endomorphism ring subring tensor product

Reference(s):

  • I. Kaplansky. On the Dimension of Modules and Algebras, X: A Right Hereditary Ring which is not left Hereditary. (1958) @ Main theorem


Legend
  • = has the property
  • = does not have the property
  • = information not in database
Name Measure
global dimension left: 2right: 1
weak global dimension 0
Name Description
Jacobson radical $\{0\}$
Left singular ideal $\{0\}$
Right singular ideal $\{0\}$