Nathan Mendelsohn
Encyclopedia
Nathan Saul Mendelsohn, (April 14, 1917 – July 4, 2006) was an American
-born mathematician
who lived and worked in Canada
. Mendelsohn was a researcher in several areas of discrete mathematics
, including group theory
and combinatorics
.
, New York City
the eldest of four children of Samuel and Sylvia (née Kirschenbaum) Mendelsohn, Jewish immigrants from Roumania, and Galicia (resp.). In 1918, he and his family moved to Toronto
, Canada
, after a fire destroyed the tenement they were living in. Mendelsohn and his family lived in a house at 13 Euclid Avenue.
Mendelsohn completed all his education at the University of Toronto
. He would have been unable to attend university had he not won a four years' tuition and books scholarship. In 1938, he was on the University of Toronto team for the first Putnam Competition
, along with Irving Kaplansky
and John Coleman. The team placed first and each of the three team members won fifty dollars. Mendelsohn was a junior, the other two were seniors. The subsequent year Mendelsohn was barred from competition as at that time the winning university set the examination for the next year and its students were barred from competition. Mendelsohn completed his Ph.D.
dissertation in 1941. It was titled "A Group-Theoretic Characterization of the General Projective Collineation Group", and summarized in the Proceedings of the National Academy of Sciences
in 1944. His supervisor was Gilbert de Beauregard Robinson
.
Mendelsohn also began practising magic tricks in high school as a means of steadying a tremor in his hands. He placed second in the 1953? International Brotherhood of Magicians
contest, behind Johnny Carson
. He could memorize a shuffled deck of cards seeing each card only once briefly, or a list of fifty objects called out in any order. He could identify the position of each card or name the card in any position.
, Mendelsohn worked on simulations of artillery and
code breaking. As with much of the mathematical work for military purposes during the time, it was classified. Although others related after fifty years what their exact role was, Nathan Mendelsohn strictly followed the Official Secrets Act
and never revealed exact details of what he had done.
From 1945 to 1947, Mendelsohn was a professor at Queen's University
in Kingston, Ontario
, Canada
. Mendelsohn's son later remarked that Mendelsohn "understood that, as a Jew, he would never get a permanent position" at Queen's, as the university "already had a Jewish professor in the department."
In 1947, Mendelsohn moved to the University of Manitoba
in Winnipeg
, Manitoba
. Mendelsohn stayed at the University of Manitoba until his retirement in 2005.
During early summers at the University of Manitoba, Mendelsohn would travel to Quebec City
to teach to supplement his $3,000 annual salary at the University of Manitoba. In 1958, Mendelsohn and Dulmage published the paper "Coverings of biparte graphs", in which the Dulmage–Mendelsohn decomposition is described. Mendelsohn is also remembered for Mendelsohn triple systems.
Mendelsohn was head of the department of mathematics at the University of Manitoba for almost a quarter of a century.
In the early 1960s, Mendelsohn returned to classified mathematics, this time at the RAND
Corporation. From 1969 to 1971, Mendelsohn was the president of the Canadian Mathematical Society
.
In 1985, Mendelsohn was the subject of a short film form the National Film Board of Canada
, titled "An Aesthetic Indulgence".
obtained through tainted blood
.
. He won the Henry Marshall Tory Medal
in 1979.
On April 15, 1999, Mendelsohn was made a member of the Order of Canada
. His citation reads, in part, that Mendelsohn is "known throughout the world as an authority in combinatorics
, classical geometry
and finite groups
".
for the highest ranking student at a Canadian University in Putnam Competition
.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
-born mathematician
Mathematics
Mathematics is the study of quantity, space, structure, and change. Mathematicians seek out patterns and formulate new conjectures. Mathematicians resolve the truth or falsity of conjectures by mathematical proofs, which are arguments sufficient to convince other mathematicians of their validity...
who lived and worked in Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. Mendelsohn was a researcher in several areas of discrete mathematics
Discrete mathematics
Discrete mathematics is the study of mathematical structures that are fundamentally discrete rather than continuous. In contrast to real numbers that have the property of varying "smoothly", the objects studied in discrete mathematics – such as integers, graphs, and statements in logic – do not...
, including group theory
Group theory
In mathematics and abstract algebra, group theory studies the algebraic structures known as groups.The concept of a group is central to abstract algebra: other well-known algebraic structures, such as rings, fields, and vector spaces can all be seen as groups endowed with additional operations and...
and combinatorics
Combinatorics
Combinatorics is a branch of mathematics concerning the study of finite or countable discrete structures. Aspects of combinatorics include counting the structures of a given kind and size , deciding when certain criteria can be met, and constructing and analyzing objects meeting the criteria ,...
.
Early life and education
Mendelsohn was born in 1917 in BrooklynBrooklyn
Brooklyn is the most populous of New York City's five boroughs, with nearly 2.6 million residents, and the second-largest in area. Since 1896, Brooklyn has had the same boundaries as Kings County, which is now the most populous county in New York State and the second-most densely populated...
, New York City
New York City
New York is the most populous city in the United States and the center of the New York Metropolitan Area, one of the most populous metropolitan areas in the world. New York exerts a significant impact upon global commerce, finance, media, art, fashion, research, technology, education, and...
the eldest of four children of Samuel and Sylvia (née Kirschenbaum) Mendelsohn, Jewish immigrants from Roumania, and Galicia (resp.). In 1918, he and his family moved to Toronto
Toronto
Toronto is the provincial capital of Ontario and the largest city in Canada. It is located in Southern Ontario on the northwestern shore of Lake Ontario. A relatively modern city, Toronto's history dates back to the late-18th century, when its land was first purchased by the British monarchy from...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, after a fire destroyed the tenement they were living in. Mendelsohn and his family lived in a house at 13 Euclid Avenue.
University of Toronto
The University of Toronto is a public research university in Toronto, Ontario, Canada, situated on the grounds that surround Queen's Park. It was founded by royal charter in 1827 as King's College, the first institution of higher learning in Upper Canada...
. He would have been unable to attend university had he not won a four years' tuition and books scholarship. In 1938, he was on the University of Toronto team for the first Putnam Competition
William Lowell Putnam Mathematical Competition
The William Lowell Putnam Mathematical Competition, often abbreviated to the Putnam Competition, is an annual mathematics competition for undergraduate college students of the United States and Canada, awarding scholarships and cash prizes ranging from $250 to $2,500 for the top students and $5,000...
, along with Irving Kaplansky
Irving Kaplansky
Irving Kaplansky was a Canadian mathematician.-Biography:He was born in Toronto, Ontario, Canada, after his parents emigrated from Poland and attended the University of Toronto as an undergraduate. After receiving his Ph.D...
and John Coleman. The team placed first and each of the three team members won fifty dollars. Mendelsohn was a junior, the other two were seniors. The subsequent year Mendelsohn was barred from competition as at that time the winning university set the examination for the next year and its students were barred from competition. Mendelsohn completed his Ph.D.
Ph.D.
A Ph.D. is a Doctor of Philosophy, an academic degree.Ph.D. may also refer to:* Ph.D. , a 1980s British group*Piled Higher and Deeper, a web comic strip*PhD: Phantasy Degree, a Korean comic series* PhD Docbook renderer, an XML renderer...
dissertation in 1941. It was titled "A Group-Theoretic Characterization of the General Projective Collineation Group", and summarized in the Proceedings of the National Academy of Sciences
Proceedings of the National Academy of Sciences
The Proceedings of the National Academy of Sciences of the United States of America, usually referred to as PNAS, is the official journal of the United States National Academy of Sciences...
in 1944. His supervisor was Gilbert de Beauregard Robinson
Gilbert de Beauregard Robinson
Gilbert de Beauregard Robinson was a Canadian mathematician most famous for his work on combinatorics and representation theory of the symmetric groups, including the Robinson-Schensted algorithm.-Biography:...
.
Mendelsohn also began practising magic tricks in high school as a means of steadying a tremor in his hands. He placed second in the 1953? International Brotherhood of Magicians
International Brotherhood of Magicians
International Brotherhood of Magicians is the world's largest organization for professional and amateur magicians, with approximately 15,000 members worldwide. The headquarters is in St...
contest, behind Johnny Carson
Johnny Carson
John William "Johnny" Carson was an American television host and comedian, known as host of The Tonight Show Starring Johnny Carson for 30 years . Carson received six Emmy Awards including the Governor Award and a 1985 Peabody Award; he was inducted into the Television Academy Hall of Fame in 1987...
. He could memorize a shuffled deck of cards seeing each card only once briefly, or a list of fifty objects called out in any order. He could identify the position of each card or name the card in any position.
Career
During the Second World WarWorld War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
, Mendelsohn worked on simulations of artillery and
code breaking. As with much of the mathematical work for military purposes during the time, it was classified. Although others related after fifty years what their exact role was, Nathan Mendelsohn strictly followed the Official Secrets Act
Official Secrets Act
The Official Secrets Act is a stock short title used in the United Kingdom, Ireland, India and Malaysia and formerly in New Zealand for legislation that provides for the protection of state secrets and official information, mainly related to national security.-United Kingdom:*The Official Secrets...
and never revealed exact details of what he had done.
From 1945 to 1947, Mendelsohn was a professor at Queen's University
Queen's University
Queen's University, , is a public research university located in Kingston, Ontario, Canada. Founded on 16 October 1841, the university pre-dates the founding of Canada by 26 years. Queen's holds more more than of land throughout Ontario as well as Herstmonceux Castle in East Sussex, England...
in Kingston, Ontario
Kingston, Ontario
Kingston, Ontario is a Canadian city located in Eastern Ontario where the St. Lawrence River flows out of Lake Ontario. Originally a First Nations settlement called "Katarowki," , growing European exploration in the 17th Century made it an important trading post...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. Mendelsohn's son later remarked that Mendelsohn "understood that, as a Jew, he would never get a permanent position" at Queen's, as the university "already had a Jewish professor in the department."
In 1947, Mendelsohn moved to the University of Manitoba
University of Manitoba
The University of Manitoba , in Winnipeg, Manitoba, Canada, is the largest university in the province of Manitoba. It is Manitoba's most comprehensive and only research-intensive post-secondary educational institution. It was founded in 1877, making it Western Canada’s first university. It placed...
in Winnipeg
Winnipeg
Winnipeg is the capital and largest city of Manitoba, Canada, and is the primary municipality of the Winnipeg Capital Region, with more than half of Manitoba's population. It is located near the longitudinal centre of North America, at the confluence of the Red and Assiniboine Rivers .The name...
, Manitoba
Manitoba
Manitoba is a Canadian prairie province with an area of . The province has over 110,000 lakes and has a largely continental climate because of its flat topography. Agriculture, mostly concentrated in the fertile southern and western parts of the province, is vital to the province's economy; other...
. Mendelsohn stayed at the University of Manitoba until his retirement in 2005.
During early summers at the University of Manitoba, Mendelsohn would travel to Quebec City
Quebec City
Quebec , also Québec, Quebec City or Québec City is the capital of the Canadian province of Quebec and is located within the Capitale-Nationale region. It is the second most populous city in Quebec after Montreal, which is about to the southwest...
to teach to supplement his $3,000 annual salary at the University of Manitoba. In 1958, Mendelsohn and Dulmage published the paper "Coverings of biparte graphs", in which the Dulmage–Mendelsohn decomposition is described. Mendelsohn is also remembered for Mendelsohn triple systems.
Mendelsohn was head of the department of mathematics at the University of Manitoba for almost a quarter of a century.
In the early 1960s, Mendelsohn returned to classified mathematics, this time at the RAND
RAND
RAND Corporation is a nonprofit global policy think tank first formed to offer research and analysis to the United States armed forces by Douglas Aircraft Company. It is currently financed by the U.S. government and private endowment, corporations including the healthcare industry, universities...
Corporation. From 1969 to 1971, Mendelsohn was the president of the Canadian Mathematical Society
Canadian Mathematical Society
The Canadian Mathematical Society is an association of professional mathematicians dedicated to the interests of mathematical research and education in Canada.It was originally conceived in June 1945 as the Canadian Mathematical Congress...
.
In 1985, Mendelsohn was the subject of a short film form the National Film Board of Canada
National Film Board of Canada
The National Film Board of Canada is Canada's twelve-time Academy Award-winning public film producer and distributor. An agency of the Government of Canada, the NFB produces and distributes documentary, animation, alternative drama and digital media productions...
, titled "An Aesthetic Indulgence".
Retirement
Mendelsohn retired from the University of Manitoba in 2005. He died on July 4, 2006 from hepatitis CHepatitis C
Hepatitis C is an infectious disease primarily affecting the liver, caused by the hepatitis C virus . The infection is often asymptomatic, but chronic infection can lead to scarring of the liver and ultimately to cirrhosis, which is generally apparent after many years...
obtained through tainted blood
Health Management Associates Scandal
Health Management Associates is a defunct Arkansas-based company involved in a blood-management scandal during the 1980s.-HMA scandal:The Health Management Associates Scandal refers to the sale of tainted blood from HMA to Canadian blood banks.HMA was contracted by the state of Arkansas to provide...
.
Awards
In 1957, Mendelsohn was made a fellow of the Royal Society of CanadaRoyal Society of Canada
The Royal Society of Canada , may also operate under the more descriptive name RSC: The Academies of Arts, Humanities and Sciences of Canada , is the oldest association of scientists and scholars in Canada...
. He won the Henry Marshall Tory Medal
Henry Marshall Tory Medal
The Henry Marshall Tory Medal is an award of the Royal Society of Canada "for outstanding research in a branch of astronomy, chemistry, mathematics, physics, or an allied science". It is named in honour of Henry Marshall Tory and is awarded bi-annually. The award consists of a gold plated silver...
in 1979.
On April 15, 1999, Mendelsohn was made a member of the Order of Canada
Order of Canada
The Order of Canada is a Canadian national order, admission into which is, within the system of orders, decorations, and medals of Canada, the second highest honour for merit...
. His citation reads, in part, that Mendelsohn is "known throughout the world as an authority in combinatorics
Combinatorics
Combinatorics is a branch of mathematics concerning the study of finite or countable discrete structures. Aspects of combinatorics include counting the structures of a given kind and size , deciding when certain criteria can be met, and constructing and analyzing objects meeting the criteria ,...
, classical geometry
Geometry
Geometry arose as the field of knowledge dealing with spatial relationships. Geometry was one of the two fields of pre-modern mathematics, the other being the study of numbers ....
and finite groups
Group theory
In mathematics and abstract algebra, group theory studies the algebraic structures known as groups.The concept of a group is central to abstract algebra: other well-known algebraic structures, such as rings, fields, and vector spaces can all be seen as groups endowed with additional operations and...
".
Nathan Mendelsohn Prize
In 2008 the Nathan Mendelsohn Prize was established by his family at the University of ManitobaUniversity of Manitoba
The University of Manitoba , in Winnipeg, Manitoba, Canada, is the largest university in the province of Manitoba. It is Manitoba's most comprehensive and only research-intensive post-secondary educational institution. It was founded in 1877, making it Western Canada’s first university. It placed...
for the highest ranking student at a Canadian University in Putnam Competition
William Lowell Putnam Mathematical Competition
The William Lowell Putnam Mathematical Competition, often abbreviated to the Putnam Competition, is an annual mathematics competition for undergraduate college students of the United States and Canada, awarding scholarships and cash prizes ranging from $250 to $2,500 for the top students and $5,000...
.
External links
- An Aesthetic Indulgence. A short film about Mendelsohn.
- An Aesthetic Indulgence. National Film Board of CanadaNational Film Board of CanadaThe National Film Board of Canada is Canada's twelve-time Academy Award-winning public film producer and distributor. An agency of the Government of Canada, the NFB produces and distributes documentary, animation, alternative drama and digital media productions...
webpage.