Emma Markovna Lehmer ('' née'' Trotskaia) (November 6, 1906 – May 7, 2007) was a

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

known for her work on reciprocity laws in algebraic number theory. She preferred to deal with complex number fields and integers, rather than the more abstract aspects of the theory.

Biography

She was born in Samara,

Russian Empire The Russian Empire was an empire and the final period of the Russian monarchy from 1721 to 1917, ruling across large parts of Eurasia. It succeeded the Tsardom of Russia following the Treaty of Nystad, which ended the Great Northern War. ...

, but her father's job as a representative with a Russian sugar company moved the family to Harbin, China in 1910. Emma was tutored at home until the age of 14, when a school was opened locally. She managed to make her way to the US for her higher education. At

UC Berkeley The University of California, Berkeley (UC Berkeley, Berkeley, Cal, or California) is a public land-grant research university in Berkeley, California. Established in 1868 as the University of California, it is the state's first land-grant uni ...

, she started out in engineering in 1924, but found her niche in mathematics. One of her professors was Derrick N. Lehmer, the number theorist well known for his work on prime number tables and factorizations. While working for him at Berkeley finding pseudosquares, she met his son, her future husband Derrick H. Lehmer. Upon her graduation summa cum laude with a

B.A. Bachelor of arts (BA or AB; from the Latin ', ', or ') is a bachelor's degree awarded for an undergraduate program in the arts, or, in some cases, other disciplines. A Bachelor of Arts degree course is generally completed in three or four yea ...

in Mathematics (1928), Emma married the younger Lehmer. They moved to Brown University, where Emma received her

M.Sc. A Master of Science ( la, Magisterii Scientiae; abbreviated MS, M.S., MSc, M.Sc., SM, S.M., ScM or Sc.M.) is a master's degree in the field of science awarded by universities in many countries or a person holding such a degree. In contrast to ...

, and Derrick his

Ph.D. A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is ...

, both in 1930. Emma did not obtain a Ph.D. herself; she claimed there were many advantages to not holding a doctorate. The Lehmers had two children, Laura (1932) and Donald (1934).

Contributions

Lehmer did independent mathematical work, including a translation from Russian to English of Pontryagin's book ''Topological Groups''. She worked closely with her husband on many projects; 21 of her 56 publications were joint work with him. Her publications were mainly in number theory and computation, with emphasis on reciprocity laws, special primes, and congruences. She proved that there were infinitely many Fibonacci pseudoprimes.

Paul Halmos Paul Richard Halmos ( hu, Halmos Pál; March 3, 1916 – October 2, 2006) was a Hungarian-born American mathematician and statistician who made fundamental advances in the areas of mathematical logic, probability theory, statistics, operator ...

, in his book ''I want to be a mathematician: An automathography'', wrote about Lehmer's translation of Pontryagin's ''Topological Groups'': "I read the English translation by Mrs. Lehmer (usually referred to as Emma Lemma)...". Several later publications repeated Halmos' reference to reinforce the significance of Lehmer's translation. During

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

, she authored the paper "Simplified Rule for Determining Spacing in Train Bombing on Stationary Targets" and co-authored three others for the Statistical Laboratory at the University of California. With her husband, she co-founded the

West Coast Number Theory West Coast Number Theory (WCNT), a meeting that has also been known variously as the Western Number Theory Conference and the Asilomar Number Theory meeting, is an annual gathering of number theorists first organized by D. H. and Emma Lehmer at t ...

conference. Emma and Derrick Lehmer both have

Erdős number The Erdős number () describes the "collaborative distance" between mathematician Paul Erdős and another person, as measured by authorship of mathematical papers. The same principle has been applied in other fields where a particular individual ...

two. They published a joint paper with

John Brillhart John David Brillhart (November 13, 1930 – May 21, 2022) was a mathematician who worked in number theory at the University of Arizona. Early life and education Brillhart was born on November 13, 1930 in Berkeley, California. He studied at the U ...

in 1964 on bounds on consecutive power residues. Brillhart published a paper on the Rudin-Shapiro sequence with Erdős and Morton in 1983.

Notes

*''Notable Women in Mathematics, a Biographical Dictionary'', edited by Charlene Morrow and Teri Perl, Greenwood Press, 1998. pp 123–128

External links

Biographies of Women Mathematicians
* {{DEFAULTSORT:Lehmer, Emma 1906 births 2007 deaths Russian centenarians Emigrants from the Russian Empire to the United States American centenarians American women mathematicians 20th-century American mathematicians 21st-century American mathematicians 20th-century American women scientists 20th-century women mathematicians 21st-century women mathematicians Women centenarians 21st-century American women