From the 1 of 8 linked papers with an AI index.
8 papers
A Three-Dimensional Operator System without the Smith--Ward Property
Marcel Scherer
The paper builds a three‑dimensional hyperrigid operator system inside a matrix amplification of the reduced C*-algebra of the free group, whose identity map lacks a unital complet…
On the spectral radius of operator tuples
Marcel Scherer, Orr Shalit, Eli Shamovich
In recent work, Shalit and Shamovich associated to every operator space structure on a spectral radius function on -tuples of ope…
Empirical bounds for commuting dilations of free unitaries and the universal commuting dilation constant
Malte Gerhold, Marcel Scherer, Orr Shalit
For a tuple of Hilbert space operators, the 'commuting dilation constant' is the smallest number such that the operators of are a simultaneous compression of commuting…
The Hyperrigidity Conjecture for Spectrahedra
Marcel Scherer
We show that if K is a compact spectrahedron whose set of extreme points is closed, then the operator system of continuous affine functions on K is hyperrigid in the C*-algebra C(e…
A C*-cover lattice dichotomy
Adam Humeniuk, Christopher Ramsey, Marcel Scherer
In this paper, we show that the lattice of C*-covers of a non-selfadjoint operator algebra is either one point or uncountable. We prove that there are non-selfadjoint operator alge…
The SOT-closure of the set of 2-isometries
Marcel Scherer
We show that the set of -isometries on an infinite-dimensional Hilbert space is not closed in the strong operator topology. In fact, we prove that its SOT-closure coincides with…