PREFACE to Volume 2 of Helmut Wielandt's mathematical Works.
 
This second volume of Helmut Wielandt's Mathematical Works contains his
contributions to matrix theory and analysis.
 
In about two dozen papers of moderate length, Wielandt has deeply
influenced matrix theory and linear algebra, and those parts of analysis
and numerical mathematics that he investigated. Wielandt is a highly
creative mathematician who had a vision, unusual for his time, of the
proper balance in mathematics between the abstract and general on the
one hand and the more concrete and specific on the other, as is
demonstrated by his extraordinarily prescient acceptance speech to the
Heidelberg Academy in 1961/62 reprinted in these volumes. Add to this
the legendary sparseness and beauty of his style, and perhaps one
obtains some explanation of the continuing importance of Wielandt's
work.
 
A word needs to be said about the nature of the commentaries in this
volume. I asked contributors to choose the paper they wished to discuss,
and this has resulted in several commentaries being received on some
papers and none on others. Contributors were also asked to remark on
recent developments of the topics under discussion in order to make
their observations useful to researchers of today. It is remarkable how
little overlap there is in commentaries on the same paper, which again
attests to the scope of the development of Wielandt's ideas.
 
Commentaries appear after the corresponding publications, except that
Olga Taussky's many contributions appear in one article by her
expressed wish. My thanks are due to all contributors, and to my
students, Ahmad Muchlis and Judith McDonald, who helped in organization
the commentaries. My thanks are also due to Manfred Karbe, the
mathematics editor at de Gruyter's for his constant encouragement and
help.
 
 
HS   14:05:36  11/5/1995