116 citations · 1.1k across the 72 of their papers we have counts for
5 papers · 1 filter
Extreme points of matrix convex sets, free spectrahedra and dilation theory
Eric Evert, J. William Helton, Igor Klep +1
For matrix convex sets a unified geometric interpretation of notions of extreme points and of Arveson boundary points is given. These notions include, in increasing order of streng…
There are many more positive maps than completely positive maps
Igor Klep, Scott McCullough, Klemen Šivic +1
A linear map between matrix spaces is positive if it maps positive semidefinite matrices to positive semidefinite ones, and is called completely positive if all its ampliations are…
Regular and positive noncommutative rational functions
Igor Klep, James Eldred Pascoe, Jurij Volčič
Call a noncommutative rational function regular if it has no singularities, i.e., is defined for all tuples of self-adjoint matrices . In this article regular noncomm…
Circular Free Spectrahedra
Eric Evert, J. William Helton, Igor Klep +1
This paper considers matrix convex sets invariant under several types of rotations. It is known that matrix convex sets that are free semialgebraic are solution sets of Linear Matr…
Bianalytic Maps Between Free Spectrahedra
Meric Augat, J. William Helton, Igor Klep +1
Linear matrix inequalities (LMIs) play a role in many areas of applications and the set of solutions to one is called…