4 papers
SIC-POVMs and orders of real quadratic fields
Gene S. Kopp, Jeffrey C. Lagarias
This paper concerns SIC-POVMs and their relationship to class field theory. SIC-POVMs are generalized quantum measurements (POVMs) described by equiangular complex lines thro…
Unit-generated orders of real quadratic fields I. Class number bounds
Gene S. Kopp, Jeffrey C. Lagarias
Unit-generated orders of a quadratic field are orders of the form , where is a unit in the quadratic field. If the order $\math…
The Shintani--Faddeev modular cocycle: Stark units from -Pochhammer ratios
Gene S. Kopp
We give a new interpretation of Stark units associated to real quadratic fields as real multiplication values of a modular cocycle. The cocycle of interest is a meromorphic factor…
A Constructive Approach to Zauner's Conjecture via the Stark Conjectures
Marcus Appleby, Steven T Flammia, Gene S Kopp
We propose a construction of complex equiangular lines in , also known as SICPOVMs, conjectured by Zauner to exist for all d. The construction gives a putativel…