Seminar

Subscribe to Seminar
Monday, January 31, 2011 12:30 pm - 1:00 pm EST (GMT -05:00)

Gus Gutoski: Short quantum games characterize PSPACE

Gus Gutoski, Institute for Quantum Computing

Abstract

I will present material from http://arxiv.org/abs/1011.2787. The abstract at that link is included below. Essentially, the result is a strengthening of the QIP=PSPACE result of Jain, Ji, Upadhyay, and Watrous from 2009. A goal of this talk is to clarify the statement and meaning of the multiplicative weights update method and illustrate how it can be used to prove space bounds in quantum complexity theory.

Monday, January 17, 2011 12:30 pm - 1:30 pm EST (GMT -05:00)

Mohammad Ansari: The Kondo effect

Mohammad Ansari, Institute for Quantum Computing

Abstract

With lowering temperature, a qubit may become strongly coupled to the reservoirs. This can result into some exotic situations such as: the appearance of full conductivity instead of current blockade in a quantum dot, increasing resistivity with lowering temperature in a metal, and the appearance of microresonators in the critical current noise in a Josephson junction. In this talk, some of these phenomena are discussed.

Friday, November 19, 2010 3:30 pm - 4:30 pm EST (GMT -05:00)

David Jao: Constructing Elliptic Curve Isogenies in Quantum Subexponential Time

Given two elliptic curves over a finite field having the same cardinality and endomorphism ring, it is known that the curves admit an isogeny (a.k.a. algebraic map) between them, but finding such an isogeny is believed to be computationally difficult. The fastest known classical algorithm for this problem requires exponential time, and prior to our work no faster quantum algorithm was known. We show that this problem can be solved in subexponential time on a quantum computer, assuming the