@book{7894922789014a1d98e3fbd920631269,

title = "Disproof of two conjectures of George Weiss",

abstract = "Two conjectures that were posed by Weiss almost ten years ago are shown not to hold. The first conjecture states that a scalar operator is admissible if and only a certain resolvent estimate holds. The second was posed by Weiss together with Russell and states that a system is exactly observable if and only if a test similar to the Hautus test for finite-dimensional systems holds. The $C_0$-semigroup in both counter-examples is analytic and possesses a basis of eigenfunctions.",

keywords = "METIS-141343, IR-65733, EWI-3366, MSC-93A05, MSC-93B07, MSC-93C25, MSC-47D60",

author = "B. Jacob and Birgit Jacob and Zwart, {Heiko J.}",

note = "Imported from MEMORANDA",

year = "2000",

language = "Undefined",

series = "Memorandum Faculteit TW",

publisher = "University of Twente, Department of Applied Mathematics",

number = "1546",

}