Vivian "Vob" O'Brien (1924 – December 24, 2010) was an American applied mathematician and physicist whose research included

fluid dynamics In physics, physical chemistry and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids – liquids and gases. It has several subdisciplines, including (the study of air and other gases in motion ...

and

visual perception Visual perception is the ability to detect light and use it to form an image of the surrounding Biophysical environment, environment. Photodetection without image formation is classified as ''light sensing''. In most vertebrates, visual percept ...

. She worked for many years as a researcher at

Johns Hopkins University The Johns Hopkins University (often abbreviated as Johns Hopkins, Hopkins, or JHU) is a private university, private research university in Baltimore, Maryland, United States. Founded in 1876 based on the European research institution model, J ...

, and is the namesake of the

Craik–O'Brien–Cornsweet illusion The Cornsweet illusion, also known as the Craik–O'Brien–Cornsweet illusion or the Craik–Cornsweet illusion, is an optical illusion that was described in detail by Tom Cornsweet in the late 1960s. Kenneth Craik and Vivian O'Brien had made ea ...

Education and career

O'Brien was originally from

Baltimore Baltimore is the most populous city in the U.S. state of Maryland. With a population of 585,708 at the 2020 census and estimated at 568,271 in 2024, it is the 30th-most populous U.S. city. The Baltimore metropolitan area is the 20th-large ...

, and was educated at Eastern High School (Baltimore) and then

Goucher College Goucher College ( ') is a Private university, private Liberal arts colleges in the United States, liberal arts college in Towson, Maryland, United States. Founded in 1885 as a Nonsectarian, nonsecterian Women's colleges in the United States, ...

, where she earned a bachelor's degree in mathematics in 1945. Because of

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

, technical jobs were open to women at the time, and she began working in aerodynamics as a

computer A computer is a machine that can be Computer programming, programmed to automatically Execution (computing), carry out sequences of arithmetic or logical operations (''computation''). Modern digital electronic computers can perform generic set ...

for the

Glenn L. Martin Company The Glenn L. Martin Company, also known as The Martin Company from 1917 to 1961, was an American aircraft and aerospace industry, aerospace manufacturing company founded by aviation pioneer Glenn L. Martin. The Martin Company produced many impo ...

. She became a research assistant in aerodynamics at Johns Hopkins University in 1947, and while doing so earned two master's degrees, in mathematics in 1950 and in engineering aeronautics in 1954. In 1955 she became a principal staff physicist at the Eisenhower Research Center of the

Johns Hopkins Applied Physics Laboratory The Johns Hopkins University Applied Physics Laboratory (or simply Applied Physics Laboratory, or APL) is a not-for-profit university-affiliated research center (UARC) in Howard County, Maryland. It is affiliated with Johns Hopkins University ...

, a position she kept for over 30 years until her retirement in 1986. She completed a Ph.D. in fluid mechanics in 1960, becoming the first female employee of the Applied Physics Laboratory with a doctorate.

Research

O'Brien's research included

aerodynamics Aerodynamics () is the study of the motion of atmosphere of Earth, air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics, and is an ...

magnetohydrodynamics In physics and engineering, magnetohydrodynamics (MHD; also called magneto-fluid dynamics or hydromagnetics) is a model of electrically conducting fluids that treats all interpenetrating particle species together as a single Continuum ...

, the flow of blood through the human eye, and visual perception. She is the namesake of the

in the optical perception of brightness.

Recognition

O'Brien was named a

Fellow of the American Physical Society The American Physical Society honors members with the designation ''Fellow'' for having made significant accomplishments to the field of physics. The following lists are divided chronologically by the year of designation. * List of fellows of the ...

(APS) in 1976, following a nomination by the APS Division of Fluid Dynamics.

References

{{DEFAULTSORT:OBrien, Vivian 1924 births 2010 deaths Scientists from Baltimore 20th-century American mathematicians American physicists American women physicists Goucher College alumni Johns Hopkins University alumni Fellows of the American Physical Society 21st-century American women 20th-century American women mathematicians