It is my pleasure to present the report of the Thomas Stieltjes
Institute for Mathematics on the years 1998 and 1999. After the
report on the single year 1997, the tradition of biennial reports is
resumed. The report covers the end of the first five year period as
a research school and the start of the second. On June 4, 1999, the
recognition of the Stieltjes Institute as a research school was
renewed by the Royal Netherlands Academy for Arts and Sciences
for another five years. In the motivation the quality of the research
groups was characterised as good to excellent. In the new period
there are some changes in the research groups. Because of its
participation in an other research school the group Theoretical
Computer Science left the Stieltjes Institute. On the other hand, the
Analysis group of the Eindhoven University of Technology joined
the Stieltjes Institute. Leiden University continued to be the
administrator of the Institute.
During the past two years we have continued to care about the
quality of the research and of the graduate study. Apart from the
regular evaluation of the research by the scientific committee,
which resulted in some measures by the board, there were various
positive actions. In 1999 Professor J.A. Wellner from the University
of Washington in Seattle, USA, was the first Stieltjes Visiting
Professor. In 1999 J.A. van Hamel received the Stieltjes
Prize for the best thesis in 1997 and J.V. Stokman for the best
one in 1998. Apart from the regular seminars and workshops about
a special topic in mathematics we started with some Stieltjes
Afternoons at which lectures were given for all members of the
In this and other ways the collaboration of Stieltjes members was
enhanced. A new initiative is the organisation of Stieltjes
Weeks starting in 2000. Researchers from different universities
will lecture and work intensively with (advanced under)graduate
students from all Stieltjes universities on a topic which has broad
The quality of Stieltjes members was recognised in various ways.
H.W. Lenstra was the first mathematician to receive the prestigious
Spinoza grant from the Netherlands Organization for Scientific
Research (NWO). This will enable him to build a strong number
theory group around him. In 1998 S.M. Verduyn Lunel and in 1999
another member of the Stieltjes Institute, E.M. Opdam, received
Pioneer grants from NWO. An honorary doctorate was awarded to R.
Tijdeman by the University of Debrecen, Hungary.
The cooperation with other research schools was strengthened.
With MRI and EIDMA an application was initiated for the depth
strategy of NWO. Afterwards informal discussions started which
may lead to a national research school committee for mathematics.
In accordance with proposals in a report of the Advisory Committee
for Science and Technology (AWT) of the Ministry of Education,
Culture and Science, the Stieltjes Institute stimulated the
cooperation and coordination of teaching of mathematics students
at undergraduate level by universities participating in the Stieltjes
Finally, the person who led the Stieltjes from the beginning,
W.R. van Zwet retired from the university and passed on the
directorship. In March 1999, a successful symposium was held on
the State of the Art in Probability and Statistics, concluded by the
last official lecture by Van Zwet at Leiden University. He remained
director until July 1999. On behalf of the Stieltjes Institute I want
to thank him here for all the good things he has done for the
institute. We are still not without his good advice, for at present he
attends the meetings of the Board of the Stieltjes Institute as
director of the associated European research institute EURANDOM.