The lattice of C*-covers of an operator algebra.
Every non-selfadjoint operator algebra A generates a C*-algebra, but isomorphic copies of A can generate many non-isomorphic C*-algebras, and we call these the C*-covers of A. A celebrated result--first proved by Hamana, is that a unique minimum C*-cover for any A exists, called the C*-envelope. The C*-envelope is intrinsic to A, but non-isomorphic operator algebras A and B can share the same C*-envelope. If we instead ask that A and B share ALL the same C*-covers, must A and B be isomorphic?
The C*-covers of an operator algebra form a complete lattice, but little more is known regarding the structure of this lattice. There are multiple natural senses in which two operator algebras may have "the same" lattice of C*-covers, and we will discuss how these different senses remember different information about the operator algebras involved. This is joint work with Dr. Christopher Ramsey.