One of the first doctoral students of J. Robert Oppenheimer at the University of California, Berkeley, Phillips completed her PhD in 1933, a time when few women could pursue careers in science.

In 1935, Oppenheimer and Phillips published[1] their description of the Oppenheimer–Phillips process, an early contribution to nuclear physics that explained the behavior of accelerated nuclei of radioactive hydrogen atoms.

Phillips was also known for her refusal to cooperate with a U.S. Senate judiciary subcommittee's investigation on internal security during the McCarthy era which led to her dismissal from her professorship at Brooklyn College, where she was a professor of science from 1938 until 1952.

Intending to become an educator, Phillips studied mathematics at Oakland City College in Indiana, where she earned a bachelor of arts degree in 1926.

[2][3] She was one of the first doctoral students of J. Robert Oppenheimer, who later became scientific head of the Manhattan Project, the Allied effort to develop the Atomic bomb.

[8] In an era when few women were working as scientists, Phillips became a leading science educator and spent the majority of her career as a professor of physics.

[6] Before accepting a full-time faculty position at Brooklyn College in 1938, Phillips worked as a fellow at the Institute for Advanced Study in Princeton, New Jersey.

[2][7] Except for three years during World War II, when she taught at the University of Minnesota (1941–44), Phillips spent a decade as a professor of physics at Brooklyn College (1938–52).

[2] As a result of her refusal to cooperate with the commission as a matter of principle, Phillips, a highly regarded physics educator, was dismissed from her professorship at Brooklyn College and her part-time position at the Columbia University Radiation Laboratory.

[13] When questioned about whether she was involved with the Communist party, Phillips chose to neither confirm or deny, but to simply state that her lineage goes back just as far as any other American.

[2][7] Phillips died of coronary artery disease on November 8, 2004, at the age of ninety-seven, at Amber Manor nursing home in Petersburg, Indiana.