“The search for shock-free airfoils is sort of futile,” said Jonathan Goodman, a math professor and one of Dr. Morawetz’s colleagues at New York University at the Courant Institute for Mathematical Sciences. Dr. Morawetz’s paper on the subject, he said, was “a beautiful proof.”
With that insight, aerospace engineers now design wings to minimize shocks rather than trying to eliminate them.
In later work Dr. Morawetz studied the scattering of waves off objects. She invented a method to prove what is known as the Morawetz inequality, which describes the maximum amount of wave energy near an object at a given time. It proves that wave energy scatters rather than lingering near the object indefinitely.
“She did some very nice things that are still quoted today,” said Louis Nirenberg, a New York University mathematician who first met Dr. Morawetz as a graduate student.
He said he attended a general relativity conference a few weeks ago. “People there were using her inequalities,” he said.
Cathleen Synge was born on May 5, 1923, in Toronto, the daughter of Irish immigrants. Her father, John Lighton Synge, was a physicist and mathematician known for research that used a geometric approach to study Einstein’s theory of general relativity. Her mother, the former Elizabeth Eleanor Mabel Allen, had been a math major in college but dropped out when she married. Dr. Morawetz credited her mother with encouraging her to have a career.
She earned a bachelor’s degree in mathematics at the University of Toronto in 1945, the same year she married Herbert Morawetz, a polymer chemist.
She toyed with the idea of going to India as a teacher, but a Toronto math professor who was…