The 11th Workshop on Numerical Ranges and Numerical Radii was held from 9 to 12 July 2012, at the National Sun Yat-sen University, Kaohsiung, Taiwan (http://www.math.nsysu.edu.tw/~wong/WONRA2012/).
A special session on 11 July was dedicated to Professor Pei Yuan Wu for his contribution to matrix and operator theory, especially on the study of numerical ranges and numerical radii. This issue consists of papers on these topics, and most of them were presented in the workshop.
The study of numerical ranges and numerical radii has an extended history, and it is still under active research with connections to many different subjects. In this special issue, there are papers relating to spectral theory, cone theory, combinatorial matrix theory, numerical linear algebra, quantum information sciences, special classes of operators, norms, preserver problems, etc. We are happy to play a supporting role to the continuous development and growth of the study of numerical ranges and numerical radii.
We express our sincere thanks to the contributors, reviewers and other editors (Kirkland and Audenaert) of this special issue. We would also like to thank the organizer of the 11th Workshop. Last but not least, we would like to thank Professor Pei Yuan Wu for his contribution to the study of numerical ranges and other topics in matrix and operator theory.
Guest EditorsChi Kwong Li
College of William and Mary, USA
Yiu Tung Poon
Iowa State University, USA
Ngai-Ching Wong
National Sun Yat-sen University, Taiwan