Harold Grad (January 23, 1923 in

New York City New York, often called New York City or NYC, is the most populous city in the United States. With a 2020 population of 8,804,190 distributed over , New York City is also the most densely populated major city in the U ...

– November 17, 1986) was an American applied mathematician. His work specialized in the application of statistical mechanics to

plasma physics Plasma ()πλάσμα
, Henry George Liddell, R ...

and

magnetohydrodynamics Magnetohydrodynamics (MHD; also called magneto-fluid dynamics or hydromagnetics) is the study of the magnetic properties and behaviour of electrically conducting fluids. Examples of such magnetofluids include plasmas, liquid metals ...

Work

In statistical mechanics he had developed in his thesis new methods for the solution of the

Boltzmann equation The Boltzmann equation or Boltzmann transport equation (BTE) describes the statistical behaviour of a thermodynamic system not in a state of equilibrium, devised by Ludwig Boltzmann in 1872.Encyclopaedia of Physics (2nd Edition), R. G. Ler ...

. He derived the

from Liouville equation using BBGKY hierarchy under certain limits, known as Boltzmann–Grad limit. Harold Grad was the founder of the Magneto-fluid Dynamics Division of the

Courant Institute The Courant Institute of Mathematical Sciences (commonly known as Courant or CIMS) is the mathematics research school of New York University (NYU), and is among the most prestigious mathematics schools and mathematical sciences research cente ...

and served as its head until shortly before his death From 1964 to 1967 and 1974 to 1977 he was a member of the Advisory Committee for Fusion Energy at

Oak Ridge National Laboratory Oak Ridge National Laboratory (ORNL) is a U.S. multiprogram science and technology national laboratory sponsored by the U.S. Department of Energy (DOE) and administered, managed, and operated by UT–Battelle as a federally funded research an ...

. Grad was a critic and supporter of many early fusion schemes including picket fences,

magnetic mirror A magnetic mirror, known as a magnetic trap (магнитный захват) in Russia and briefly as a pyrotron in the US, is a type of magnetic confinement device used in fusion power to trap high temperature plasma using magnetic fields. Th ...

s and Biconic cusps.

Recognition

In 1970, Grad became a member of the

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nat ...

. He was an

invited speaker at the International Congress of Mathematicians This is a list of International Congresses of Mathematicians Plenary and Invited Speakers. Being invited to talk at an International Congress of Mathematicians has been called "the equivalent, in this community, of an induction to a hall of fame." ...

in Nice in 1970 and in Stockholm in 1962. In 1981, Grad was awarded a

Guggenheim Fellowship Guggenheim Fellowships are grants that have been awarded annually since by the John Simon Guggenheim Memorial Foundation to those "who have demonstrated exceptional capacity for productive scholarship or exceptional creative ability in the ar ...

. In 1982, he was awarded the

Eringen Medal The A. C. Eringen Medal or Eringen Medal is an award given annually bthe Society of Engineering Science(SES) to an individual "in recognition of sustained outstanding achievements in Engineering Science". This award was established in 1976. The ...

from the Society of Engineering Science, and in 1986, he received the James Clerk Maxwell Prize for Plasma Physics from the American Physical Society. The Courant Institute offers the Harold Grad Memorial Prize to outstanding performance and promise as a graduate student.

Life

Dr. Grad received a bachelor's degree in electrical engineering from the

Cooper Union The Cooper Union for the Advancement of Science and Art (Cooper Union) is a private college at Cooper Square in New York City. Peter Cooper founded the institution in 1859 after learning about the government-supported École Polytechnique in ...

in 1943 and his masters at

New York University New York University (NYU) is a private research university in New York City. Chartered in 1831 by the New York State Legislature, NYU was founded by a group of New Yorkers led by then- Secretary of the Treasury Albert Gallatin. In 1832, ...

in 1945. Grad did his doctoral work under

Richard Courant Richard Courant (January 8, 1888 – January 27, 1972) was a German American mathematician. He is best known by the general public for the book '' What is Mathematics?'', co-written with Herbert Robbins. His research focused on the areas of real ...

and graduated in 1948. His thesis was on the approximation of the Boltzmann Equation by torque. He was then at the

of Mathematical Sciences of

from 1948 as associate professor and from 1957 until his death. Dr. Grad conducted research in

, the mathematical formulation of plasma physics and applications of plasma physics to nuclear fusion. He led the

department from 1956 until 1980.

References

{{DEFAULTSORT:Grad, Harold 20th-century American mathematicians Scientists from New York City New York University alumni 1923 births 1986 deaths Courant Institute of Mathematical Sciences faculty Mathematicians from New York (state) Cooper Union alumni