Richard A. Parker (born 29 January 1953, in

Surrey Surrey () is a ceremonial and non-metropolitan county in South East England, bordering Greater London to the south west. Surrey has a large rural area, and several significant urban areas which form part of the Greater London Built-up Area. ...

) is a mathematician and freelance computer programmer in

Cambridge Cambridge ( ) is a university city and the county town in Cambridgeshire, England. It is located on the River Cam approximately north of London. As of the 2021 United Kingdom census, the population of Cambridge was 145,700. Cambridge bec ...

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

. He invented many of the algorithms for computing the modular character tables of finite

simple group SIMPLE Group Limited is a conglomeration of separately run companies that each has its core area in International Consulting. The core business areas are Legal Services, Fiduciary Activities, Banking Intermediation and Corporate Service. The d ...

s. He discovered the relation between

Niemeier lattice In mathematics, a Niemeier lattice is one of the 24 positive definite even unimodular lattices of rank 24, which were classified by . gave a simplified proof of the classification. has a sentence mentioning that he found more than 10 such latt ...

s and deep holes of the

Leech lattice In mathematics, the Leech lattice is an even unimodular lattice Λ24 in 24-dimensional Euclidean space, which is one of the best models for the kissing number problem. It was discovered by . It may also have been discovered (but not published) by ...

, and constructed Parker's

Moufang loop Moufang is the family name of the following people: * Christoph Moufang (1817–1890), a Roman Catholic cleric * Ruth Moufang (1905–1977), a German mathematician, after whom several concepts in mathematics are named: ** Moufang–Lie algebra ** ...

of order 2¹³ (which was used by

John Horton Conway John Horton Conway (26 December 1937 – 11 April 2020) was an English mathematician active in the theory of finite groups, knot theory, number theory, combinatorial game theory and coding theory. He also made contributions to many branches ...

in his construction of the

monster group In the area of abstract algebra known as group theory, the monster group M (also known as the Fischer–Griess monster, or the friendly giant) is the largest sporadic simple group, having order 246320597611213317192329314147 ...

Books

* Conway, J. H.; Sloane, N. J. A. (1999). ''Sphere packings, lattices and groups.'' (3rd ed.) With additional contributions by E. Bannai, R. E. Borcherds, John Leech, Simon P. Norton, A. M. Odlyzko, R. A. Parker, L. Queen and B. B. Venkov. Grundlehren der Mathematischen Wissenschaften, 290. New York: Springer-Verlag. . * *''An Atlas of Brauer Characters'' (London Mathematical Society Monographs) by Christopher Jansen, Klaus Lux, Richard Parker, Robert Wilson. Oxford University Press, U.S. (October 1, 1995)

References

Alumni of St John's College, Cambridge 20th-century English mathematicians 21st-century English mathematicians Group theorists 1953 births Living people {{UK-mathematician-stub