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William Hunter McCrea
RAS obituary
Fellow of the RAS; President, Secretary, Treasurer and Foreign Correspondent of the Society; distinguished international relativist and astrophysicist; inspiring teacher and leader; a good friend and a diligent ambassador for science.
William Hunter McCrea was born on W 13 December 1904, son of Robert Hunter McCrea, in Dublin, Ireland. In 1906 his family moved to England, first to Kent, before settling in Chesterfield. He was educated at Chesterfield Grammar School, entering Trinity College, Cambridge, in 1923 to begin a notable career as Wrangler, Rayleigh Prizeman, Sheepshanks Exhibitioner and Isaac Newton Student. On graduating in 1926, he undertook postgraduate studies under the supervision of R H Fowler, producing a thesis "Problems concerning the outer layers of the Sun" in 1929. During his postgraduate studies he spent a year at Göttingen University as a Rouse Ball Travelling Fellow.
His first academic appointment came in 1930 at the University of Edinburgh with Whittaker, followed two years later by a Readership and Assistant Professorship at Imperial College London (1932-36), prior to appointment as Professor of Pure Mathematics at the Queen's University of Belfast (1936-44). After the war, which included service in operational research in PM S Blackett's group, he was appointed to the Chair of Mathematics at Royal Holloway College, London (1944-66) and in 1966 became Research Professor in Theoretical Astronomy at the newly founded Astronomy Centre at the University of Sussex from which he "retired" in 1972.
He was elected a Fellow of the Royal Society in 1952, was knighted for his services to astronomy in 1985, and was made a Freeman of the City of London in 1988. He was the holder of honorary degrees from universities both in the UK and abroad, was a Bye-Fellow at Caius College, Cambridge, a visiting professor at universities on four continents, and a member of the Akademie Leopoldina and the Turin Academy of Sciences. During his career he published some 280 papers, 6 books and contributed approximately 250 incisive, critical reviews to the Zentralblat für Mathematik.
Bill was elected a Fellow of the Royal Astronomical Society on 10 May 1929 and thereafter served the Society in many capacities, for some years as editor of Monthly Notices, and held all four of the Society's Offices (a feat shared only with Sir Harold Spencer Jones): President (1961-63), Secretary (1946-49),
Treasurer (1976-79), Foreign Correspondent (1968-71). He was awarded the Gold Medal of the Society in 1976. His period as Secretary was an important contribution in revitalizing the Society following the Second World War. His foresight, wisdom and diplomatic skills contributed greatly to the prominence and success of the Society subsequently. He was also an Editor of The Observatory.
Bill's scientific work encompassed astrophysics, applied mathematics and the general theory of relativity. He went to Göttingen principally to meet the leading relativists of that time. On arrival, he found the relativists had moved away, being replaced by astrophysicists who supported and encouraged his interests. He built up many relationships with the leading German astrophysicists of his generation of value not least in restoring German astronomy after the war. His relativity studies received a boost when he moved to Edinburgh where he began a fruitful collaboration with George McVittie.
Relativistic cosmology
Before the Second World War, the bulk of his published papers were on relativistic cosmology, including two papers in 1935 and 1939 on "Observable relations in relativistic cosmology a topic to which he attached considerable importance. He analysed in detail what one could deduce about the structure of the universe from astronomical observations without making a priori assumptions that the universe is isotropic and homogeneous. These papers have become of significant interest again in recent years and the second of them was recently republished in General Relativity and Gravitation Journal to make it more easily accessible to current researchers. Although his PhD thesis and early papers had been astrophysical and had led him to consider one of the most important questions of the late 20s – the finding by Cecilia Payne that hydrogen was the most abundant element in the universe – the bulk of his pre-war astrophysical output was his concise, incisive, precise, and above all clear abstracts in the Zentralblat für Mathematik. Those abstracts were, in a way, the embodiment of Bill's approach to science.
Bill's most famous contribution to science was his demonstration, in collaboration with Edward A Milne, that the isotropic and homo-geneous cosmological solutions of Einstein's equations all had simple Newtonian analogues which could be derived in a straightforward manner that bypassed all the mathematical technicalities of Einstein's theory. The Milne-McCrea theorem of 1934 subsequently became the basis for the exposition of cosmology and can be found in all relevant textbooks. This desire for rigorous simplification can also be found in his important paper showing that the C-field proposed by Hoyle to provide the continuous creation of matter required to sustain steady-state cosmology did not demand a modification of Einstein's theory of General Relativity. It could be accommodated by a judicious choice of the equation of state of the matter to represent a vacuum stress. Thirty years later this model is standard in the representation of the inflationary universe.
Much of Bill's work focused upon the subtleties of Einstein's General Theory of Relativity. He always regretted never having met Einstein, but it is a measure of the regard in which he was held that he was invited to contribute the foreword to editions of Einstein's book The Meaning of Relativity. This book was widely read because Einstein took to announcing his latest unified field theory in 4th, 5th and 6th editions. Bill used to tell with amusement how these new pages of tensor analysis would be pasted on the windows of New York department stores for the public to admire.
After the war, Bill continued with astrophysics and relativity – the balance being more directed towards astrophysics. His argument with Herbert Dingle on the Clock Paradox is a classic of its kind the resolution being Bill's paper on "A class of transformations in Special Relativity" of 1959. While his expositions of steady-state cosmology were also classics, he was actively considering problems of binary stars, star formation and means to form inter-stellar molecular hydrogen. His model of star formation of 1960 resolved two of the major problems that still beset star formation theory – fragmentation of massive gas clouds into stellar masses and excess angular momentum of stellar fragments. While his theory in 1960 had certain difficulties, modern concepts of the interstellar medium suggest that his concepts deserve revisitation.
Astronomy Centre
After his move to Sussex, Bill was joined by Roger Tayler in 1967 and the new Centre was soon well established with a successful Masters teaching programme, ongoing research funding from DSIR and the Science Research Council, close links with the Royal Greenwich Observatory at Herstmonceux and a number of notable research and teaching appointments. His "retirement" in 1972 made little difference to his activity in research and service to the astronomical community. He continued to pursue his interests in a variety of cosmological and astrophysical problems. Members of the Astronomy Centre took great pleasure in celebrating the honours and landmarks that arrived in steady succession for him.
Bill was also a successful teacher. His experience of departmental administration meant that his department ran with considerable smoothness. He was never an absentee professor, but took his full share of the teaching load. He was always accessible to his postgraduate students and encouraged a wide interest in all branches of astronomy and relativity. It was clear that he was no believer in the narrow specialization that characterizes so much of scientific activity today. He did not tolerate slackness in any form yet he was always kind and encouraging, if sometimes daunting. One of the things that distinguished Bill was the way he took the same time and trouble to listen and talk to the most junior student as to the Nobel Prize-winning visitor. Young people always remember that attention and it was one of the reasons he was held in such esteem and affection. He expected the highest mathematical standards in teaching and in research; he inspired his staff and students to give just that.
It was Bill's clarity of vision, insight into the essentials of a situation and warmth of spirit that made him the perfect ambassador for UK science astronomy in particular. Whether it was as advisor and subsequently a governor, of the Dublin Institute of Advanced Study at the height of the Second World War, maintaining links between Irish and British astronomers following Irish independence in 1948, smoothing serious political differences in the UK into workable propositions, mending fences in Argentina after the Falklands War or simply as chairman of a meeting bringing a long-winded speaker gently to a conclusion, Bill possessed the necessary skills, his choice of words always correct and tactful. As with his mathematics, Bill never fudged the issues, but brought clarity, reason and common sense to bear.
In his 80s, Bill was energetic in trying to retain the RGO at Herstmonceux and was dismayed by its closure in 1998. He still travelled extensively as a speaker and advisor. Bill was extremely loyal to all the organizations he served and the activities in which he participated. All seminar speakers could expect at least one McCrea question usually simple in initial delivery but likely to spin deceptively when played. Again, many young researchers' and visitors' memories of Bill are coloured by their recollections of these incisive but gently put questions. Young astronomy Masters students giving their first public talk as part of their course felt pleased if they could answer, but also terribly chuffed that he had asked.
Although Bill seemed on first acquaintance a little shy, and so enjoyed a certain protective formality, this was soon bypassed and you discovered that the only thing he liked more than astrophysics was astrophysicists. His memberships of scientific societies and their informal dining clubs were amongst his greatest enjoyments, and his gregarious manner endeared him to colleagues all over the world.
Bill McCrea was one of the most scientifically distinguished, widely respected and best-loved astronomers in the world. He had out-lived almost all his contemporaries, but had generated two more generations of friends, collaborators and admirers. A gentleman of sterling character; a friend and colleague of great loyalty and charm; a scientist blessed with great abilities that he used critically and with long-lasting effect; his death on 25 April 1999 brings to an end a long chapter in British astronomy, leaving many fond memories of a truly remarkable person.
JD Barrow, University of Sussex and D McNally, University of London Observatory.
His first academic appointment came in 1930 at the University of Edinburgh with Whittaker, followed two years later by a Readership and Assistant Professorship at Imperial College London (1932-36), prior to appointment as Professor of Pure Mathematics at the Queen's University of Belfast (1936-44). After the war, which included service in operational research in PM S Blackett's group, he was appointed to the Chair of Mathematics at Royal Holloway College, London (1944-66) and in 1966 became Research Professor in Theoretical Astronomy at the newly founded Astronomy Centre at the University of Sussex from which he "retired" in 1972.
He was elected a Fellow of the Royal Society in 1952, was knighted for his services to astronomy in 1985, and was made a Freeman of the City of London in 1988. He was the holder of honorary degrees from universities both in the UK and abroad, was a Bye-Fellow at Caius College, Cambridge, a visiting professor at universities on four continents, and a member of the Akademie Leopoldina and the Turin Academy of Sciences. During his career he published some 280 papers, 6 books and contributed approximately 250 incisive, critical reviews to the Zentralblat für Mathematik.
Bill was elected a Fellow of the Royal Astronomical Society on 10 May 1929 and thereafter served the Society in many capacities, for some years as editor of Monthly Notices, and held all four of the Society's Offices (a feat shared only with Sir Harold Spencer Jones): President (1961-63), Secretary (1946-49),
Treasurer (1976-79), Foreign Correspondent (1968-71). He was awarded the Gold Medal of the Society in 1976. His period as Secretary was an important contribution in revitalizing the Society following the Second World War. His foresight, wisdom and diplomatic skills contributed greatly to the prominence and success of the Society subsequently. He was also an Editor of The Observatory.
Bill's scientific work encompassed astrophysics, applied mathematics and the general theory of relativity. He went to Göttingen principally to meet the leading relativists of that time. On arrival, he found the relativists had moved away, being replaced by astrophysicists who supported and encouraged his interests. He built up many relationships with the leading German astrophysicists of his generation of value not least in restoring German astronomy after the war. His relativity studies received a boost when he moved to Edinburgh where he began a fruitful collaboration with George McVittie.
Relativistic cosmology
Before the Second World War, the bulk of his published papers were on relativistic cosmology, including two papers in 1935 and 1939 on "Observable relations in relativistic cosmology a topic to which he attached considerable importance. He analysed in detail what one could deduce about the structure of the universe from astronomical observations without making a priori assumptions that the universe is isotropic and homogeneous. These papers have become of significant interest again in recent years and the second of them was recently republished in General Relativity and Gravitation Journal to make it more easily accessible to current researchers. Although his PhD thesis and early papers had been astrophysical and had led him to consider one of the most important questions of the late 20s – the finding by Cecilia Payne that hydrogen was the most abundant element in the universe – the bulk of his pre-war astrophysical output was his concise, incisive, precise, and above all clear abstracts in the Zentralblat für Mathematik. Those abstracts were, in a way, the embodiment of Bill's approach to science.
Bill's most famous contribution to science was his demonstration, in collaboration with Edward A Milne, that the isotropic and homo-geneous cosmological solutions of Einstein's equations all had simple Newtonian analogues which could be derived in a straightforward manner that bypassed all the mathematical technicalities of Einstein's theory. The Milne-McCrea theorem of 1934 subsequently became the basis for the exposition of cosmology and can be found in all relevant textbooks. This desire for rigorous simplification can also be found in his important paper showing that the C-field proposed by Hoyle to provide the continuous creation of matter required to sustain steady-state cosmology did not demand a modification of Einstein's theory of General Relativity. It could be accommodated by a judicious choice of the equation of state of the matter to represent a vacuum stress. Thirty years later this model is standard in the representation of the inflationary universe.
Much of Bill's work focused upon the subtleties of Einstein's General Theory of Relativity. He always regretted never having met Einstein, but it is a measure of the regard in which he was held that he was invited to contribute the foreword to editions of Einstein's book The Meaning of Relativity. This book was widely read because Einstein took to announcing his latest unified field theory in 4th, 5th and 6th editions. Bill used to tell with amusement how these new pages of tensor analysis would be pasted on the windows of New York department stores for the public to admire.
After the war, Bill continued with astrophysics and relativity – the balance being more directed towards astrophysics. His argument with Herbert Dingle on the Clock Paradox is a classic of its kind the resolution being Bill's paper on "A class of transformations in Special Relativity" of 1959. While his expositions of steady-state cosmology were also classics, he was actively considering problems of binary stars, star formation and means to form inter-stellar molecular hydrogen. His model of star formation of 1960 resolved two of the major problems that still beset star formation theory – fragmentation of massive gas clouds into stellar masses and excess angular momentum of stellar fragments. While his theory in 1960 had certain difficulties, modern concepts of the interstellar medium suggest that his concepts deserve revisitation.
Astronomy Centre
After his move to Sussex, Bill was joined by Roger Tayler in 1967 and the new Centre was soon well established with a successful Masters teaching programme, ongoing research funding from DSIR and the Science Research Council, close links with the Royal Greenwich Observatory at Herstmonceux and a number of notable research and teaching appointments. His "retirement" in 1972 made little difference to his activity in research and service to the astronomical community. He continued to pursue his interests in a variety of cosmological and astrophysical problems. Members of the Astronomy Centre took great pleasure in celebrating the honours and landmarks that arrived in steady succession for him.
Bill was also a successful teacher. His experience of departmental administration meant that his department ran with considerable smoothness. He was never an absentee professor, but took his full share of the teaching load. He was always accessible to his postgraduate students and encouraged a wide interest in all branches of astronomy and relativity. It was clear that he was no believer in the narrow specialization that characterizes so much of scientific activity today. He did not tolerate slackness in any form yet he was always kind and encouraging, if sometimes daunting. One of the things that distinguished Bill was the way he took the same time and trouble to listen and talk to the most junior student as to the Nobel Prize-winning visitor. Young people always remember that attention and it was one of the reasons he was held in such esteem and affection. He expected the highest mathematical standards in teaching and in research; he inspired his staff and students to give just that.
It was Bill's clarity of vision, insight into the essentials of a situation and warmth of spirit that made him the perfect ambassador for UK science astronomy in particular. Whether it was as advisor and subsequently a governor, of the Dublin Institute of Advanced Study at the height of the Second World War, maintaining links between Irish and British astronomers following Irish independence in 1948, smoothing serious political differences in the UK into workable propositions, mending fences in Argentina after the Falklands War or simply as chairman of a meeting bringing a long-winded speaker gently to a conclusion, Bill possessed the necessary skills, his choice of words always correct and tactful. As with his mathematics, Bill never fudged the issues, but brought clarity, reason and common sense to bear.
In his 80s, Bill was energetic in trying to retain the RGO at Herstmonceux and was dismayed by its closure in 1998. He still travelled extensively as a speaker and advisor. Bill was extremely loyal to all the organizations he served and the activities in which he participated. All seminar speakers could expect at least one McCrea question usually simple in initial delivery but likely to spin deceptively when played. Again, many young researchers' and visitors' memories of Bill are coloured by their recollections of these incisive but gently put questions. Young astronomy Masters students giving their first public talk as part of their course felt pleased if they could answer, but also terribly chuffed that he had asked.
Although Bill seemed on first acquaintance a little shy, and so enjoyed a certain protective formality, this was soon bypassed and you discovered that the only thing he liked more than astrophysics was astrophysicists. His memberships of scientific societies and their informal dining clubs were amongst his greatest enjoyments, and his gregarious manner endeared him to colleagues all over the world.
Bill McCrea was one of the most scientifically distinguished, widely respected and best-loved astronomers in the world. He had out-lived almost all his contemporaries, but had generated two more generations of friends, collaborators and admirers. A gentleman of sterling character; a friend and colleague of great loyalty and charm; a scientist blessed with great abilities that he used critically and with long-lasting effect; his death on 25 April 1999 brings to an end a long chapter in British astronomy, leaving many fond memories of a truly remarkable person.
JD Barrow, University of Sussex and D McNally, University of London Observatory.
William Hunter McCrea's obituary appeared in Journal of the Royal Astronomical Society 40:6 (1999), 35-36.