Complete positivity and distance-avoiding sets
نویسندگان
چکیده
منابع مشابه
Distance-Avoiding Sets in the Plane
Fix a real number d > 0. Let D = {1, d} if d 6= 1; otherwise D = {1} may simply be written as 1. A subset S ⊆ R is said to avoid D if kx− yk / ∈ D for all x, y ∈ S. For example, the union of open balls of radius 1/2 with centers in (2Z) avoids the distance 1. If instead the balls have centers in (3Z), then their union avoids {1, 2}. It is natural to ask about the “largest possible” S that avoid...
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There are two ways to turn a categorical model for pure quantum theory into one for mixed quantum theory, both resulting in a category of completely positive maps. One has quantum systems as objects, whereas the other also allows classical systems on an equal footing. The former has been axiomatized using environment structures. We extend this axiomatization to the latter by introducing decoher...
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We provide a general and consistent formulation for linear subsystem quantum dynamical maps, developed from a minimal set of postulates, primary among which is a relaxation of the usual, restrictive assumption of uncorrelated initial system-bath states. We describe the space of possibilities admitted by this formulation, namely that, far from being limited to only completely positive (CP) maps,...
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ژورنال
عنوان ژورنال: Mathematical Programming
سال: 2020
ISSN: 0025-5610,1436-4646
DOI: 10.1007/s10107-020-01562-6