Prof. Andris Ambainis

University of Latvia

Pseudorandom sets of quantum states and their applications

We study probability distributions over quantum states (complex unit vectors in n dimensions) which approximate the uniform probability distribution over the n-dimensional unit sphere. More specifically, we look at t-designs: probability distributions which are hard to distinguish from the uniform distribution, given at most t copies of a sample from the probability distribution. t-designs have been studied in both mathematics (starting with Delsarte, Goethals and Seidel, 1977) and quantum information theory. I will review the known constructions of t-designs and give a new construction of approximate t-designs. I will also describe some applications of t-designs in quantum information theory.

This is a joint work with Joseph Emerson.

Seminar schedule: http://www.physics.rutgers.edu/qcg/Seminars.html