Algebra Seminar
Sylvie Davis, Department of Pure Mathematics, University of Waterloo
"Monoids, Computation, and the State Complexity of Regular Languages"
Sylvie Davis, Department of Pure Mathematics, University of Waterloo
"Monoids, Computation, and the State Complexity of Regular Languages"
Valentina Harizanov, George Washington University
"Arithmetically categorical structures"
Michael Deveau, Department of Pure Mathematics, University of Waterloo
"Computability Theory and Some Applications"
Jeff Samuelson, Department of Pure Mathematics, University of Waterloo
"A variety of schemes, part II"
We give the general definition of schemes and discuss several examples.
MC 5479
Samuel Harris, Department of Pure Mathematics, University of Waterloo
"Applying unitary correlations to matrix-valued Tsirelson correlations"
In this talk we’ll explore another application of unitary correlations. We’ll use C*-algebraic analogues of quantum teleportation and super-dense coding to transform non-spatial unitary correlations into a matrix version of non-spatial Tsirelson correlations. On the way, we’ll also find some separations for matrix-valued Tsirelson correlations between the quantum and the quantum spatial models.
Mohammad Mahmoud, Department of Pure Mathematics, University of Waterloo
"The Isomorphism Problem of the Class of Computable Trees of Finite Rank"
Eric Boulter, Department of Pure Mathematics, University of Waterloo
"The Parallel Postulate: a 2000-year controversy"
Roger Smith, Texas A&M University
"A Galois correspondence for crossed products"
We consider a discrete group G acting by outer automorphisms on a simple unital C*-algebra A. We address the problem of characterising the C*-algebras lying between A and its crossed product by G. The main result is that these are parameterised by the subgroups of G. This is joint work with Jan Cameron.
MC 5417
Carlos Valero, Department of Pure Mathematics, University of Waterloo
"Why we Caré about the Poincaré Conjecture?"
Luke MacLean, Department of Pure Mathematics, University of Waterloo
"Different extensions of first-order logic"
How does one capture the properties that aren’t definable by first-order sentences or even theories? One way is to allow infinitary conjunctions of first-order sentences. Another is to expand the language that is being used. In this talk I will discuss the cases when these two extensions coincide, and sketch a proof by W. Craig and R.L. Vaught that a computably axiomatizable theory can be finitely axiomatized using additional predicates.