**Jim Wiegold** was a Welsh mathematician who worked in group theory.

- James Wiegold was born near Caerphilly on 15 April 1934.
- Wiegold had graduated B.Sc. with First Class Honours in Mathematics from Manchester in 1954, then spent a year working for his M.Sc. which he received one year later.
- The Pure Mathematics Department in the Faculty of Technology was led by Hanna Neumann and Wiegold had already started joint work with her on certain products of groups which they called linked products before he joined the staff at Manchester.
- In 1963 Wiegold left Manchester and returned to Wales when he was appointed as a Lecturer at the University College of South Wales and Monmouthshire, now Cardiff University.
- In 1966 Wiegold was promoted to Senior Lecturer.
- Both Bernhard and Hanna Neumann had left Manchester in the same year that Wiegold went to Cardiff.
- When Wiegold visited, Hanna Neumann held the chair of pure mathematics in the School of General Studies and Bernhard Neumann was Head of the Mathematics Department at the Institute of Advanced Studies.
- Wiegold was promoted to a Readership at Cardiff in 1969.
- In 1974 Wiegold became a professor when given a personal chair in the University College, Cardiff.
- We have already indicated the contents of Wiegold's thesis, the main results of which he published in 1959.
- In 1960, in addition to the paper with Hanna Neumann mentioned above and a short paper On a note of B H Neumann, Wiegold published two further papers On direct factors in groups and Some remarks on generalised products of groups with amalgamations.
- The range and quantity of Wiegold's mathematics make it impossible to give here anything other than an impression of the many areas on which Wiegold worked and the remarkable range of his co-authors.
- We shall, however, indicate two topics which were important to Wiegold and on which he devoted continued effort over many years.
- In 1981 Wiegold gave a five-lecture survey entitled The Schur multiplier: an elementary approach at the first Groups St Andrews conference.
- The article Wiegold wrote for the conference Proceedings based on these lectures is today the most cited of all his 127 papers.
- Having mentioned Wiegold's most cited paper, his second most cited paper is Groups with all subgroups normal-by-finite (1995) which he wrote jointly with John Lennox, Bernhard Neumann and Howard Smith.
- We promised to mention two topics that were particularly important to Wiegold: the second is growth sequences.
- In 1978, jointly with John S Wilson, he published Growth sequences of finitely generated groups and, in 1989, a second part appeared written jointly by Wiegold and Alastair G R Stewart.
- Wiegold's papers are a joy to read.
- Before leaving our discussion of Wiegold's research, we mention the importance he put on checking the correctness of any results from papers by other authors which he had used in the proof of his own theorems.
- A major contribution by Wiegold came from his editorial appointments which included being a Member of the Editorial Board of the London Mathematical Society (1973-74), Secretary of the Journal of the London Mathematical Society (1974-77), and Joint Editor in Chief (with Desmond Evans) of the Proceedings of the London Mathematical Society (1986-1992).
- Wiegold spent research visits of up to three months at the Institute of Advanced Studies, Australian National University (1965), Adelaide (1973), Aachen (1978), York University, Toronto (1979), Western Michigan (1982), Manitoba (1982), York University, Toronto (1982), Padova (1986), Aachen (1986), and Napoli (1988).

Born 15 April 1934, Trecennydd, near Caerphilly, Wales. Died 4 August 2009, Penarth, near Cardiff, Wales.

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Group Theory, Origin Wales

**Oâ€™Connor, John J; Robertson, Edmund F**: MacTutor History of Mathematics Archive