Popper commanded international audiences and conversation with him was an intellectual adventure even if a little rough animated by a myriad of philosophical problems. His intense desire to tear away at the veneer of falsity in pursuit of the truth lead him to contribute to a field of thought encompassing (among others) political theory, quantum mechanics, logic, scientific method and evolution...

Touching the 3rd Dimension (Dagstuhl Seminar 12151) Daniel Keefe, Antonio Krüger, Frank Steinicke, and Jean-Baptiste de la Rivière . . 1 Software Synthesis (Dagstuhl Seminar 12152) Ratislav Bodik, Sumit Gulwani, and Eran Yahav . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Semantic Data Management (Dagstuhl Seminar 12171) Grigoris Antoniou, Oscar Corcho, Karl Aberer, Elena...

We show that a unitary upper Hessenberg matrix with positive subdiago-nal elements is uniquely determined by its eigenvalues and the eigenvalues of a modiied principal submatrix. This provides an analog of a well-known result for Jacobi matrices.

Karl Gebhardt (1897–1948) had a distinguished career as professor of sports medicine before the Second World War. He developed sports for the disabled at a specialised orthopaedic clinic at Hohenlychen and was President of the Red Cross in Germany. During the war, Gebhardt also acted as Heinrich Himmler’s personal physician and was responsible for medical experimentation on prisoners in the con...

Karl Popper, though not trained as a physicist and embarrassed early in his career by a physics error pointed out by Einstein and Bohr, ultimately made substantial contributions to the interpretation of quantum mechanics. As was often the case, Popper initially formulated his position by criticizing the views of others—in this case Niels Bohr and Werner Heisenberg. Underlying Popper’s criticism...

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Karl Johan Åström & Richard M. Murray: Feedback Systems is published by Princeton University Press and copyrighted, © 2008, by Princeton University Press. All rights reserved. No part of this book may be reproduced in any form by any electronic or mechanical means (including photocopying, recording, or information storage and retrieval) without permission in writing from the publisher, except f...

We characterize matrices A ∈ Cn×n whose zero/nonzero pattern requires that the controllability matrix [b Ab Ab . . . An−1b] ∈ Cn×n is of full rank, where b ∈ Cn×1 has exactly one nonzero entry. When all the diagonal entries of A are nonzero we show that this occurs if and only if QAQ is unreduced upper Hessenberg, with Q being a permutation matrix for which Qb = [b1, 0, . . . , 0] T . We also c...