1994 Kirkman medal awarded to Jonathan Jedwab
From BICA (15) 1995:
The 1995 Kirkman Medals of the ICA
The 1995 Kirkman Medals of the ICA are awarded to members of the Institute who received their doctoral degrees in 1991, 1992, or 1993, and who have already produced a substantial amount of research work of exceptional quality. The Kirkman Medals were inaugurated in 1994, and the 1995 Kirkman Medals, the first to be granted, have been awarded to Jonathan Jedwab and Robert Craigen. We give summaries of the much more extensive citations and publication lists that were supplied by the nominators of these two outstanding young researchers.
Jonathan Jedwab received his Master's degree from Cambridge University and completed a doctorate at Royal Holloway College of the University of London, under the direction of Fred Piper, in 1991. Despite being only a part-time doctoral student, he completed his thesis in a record years. Since that time, he has been employed at Hewlett-Packard Laboratories, where he is involved in seven pending patents relating to the communication of digital information. At HP, Jonathan has put his deep knowledge of combinatorics to many practical purposes. His work on the HP 'bit error rate tester" was particularly innovative.
Despite the fact that he is working outside academia, Jonathan has made fundamental contributions to the theory of difference sets and binary arrays. He has extraordinary progress in using diverse mathematical areas to contribute to the theory of difference sets. One labelled his construction that showed that every abelian 2-group of order 22a+2 and exponent less than 2a+3 has a difference set as "the only completely satisfactory result in the theory of difference sets". Among other important results which he discovered, or in which he played a major role arc: the non-existence result establishing that the exponent of the group is not a necessary and sufficient condition for the existence of a difference set; characterization of groups that can contain a McFarland difference set; a structure theorem that determines precisely what Hadamard difference sets must look like for primes other than 2 or 3. Recently he has discovered a new family of parameters that have difference sets; this is the first new parameter family containing difference sets that has been found in 20 years; it includes as subfamilies almost all known families of difference sets, and it yields an infinite family of new groups that contain a McFarland difference set This major breakthrough will have an important unifying effect in the study of difference sets.
Jonathan Jedwab has made substantial contributions in both practical research and theoretical combinatorics; he is already recognized as a leading expert in the theory of difference sets.