Ralph A. Alpher; Physicist Published Theory of Big Bang

His doctoral thesis said this: After the explosion, what remained would be radiation and other matter, which Dr. Alpher dubbed ylem. This cloud of neutrons decayed and formed protons, electrons and neutrinos. As the universe cooled, the remaining neutrons, protons and electrons combined to form all the chemical elements of which the physical world is composed. His calculations found 10 atoms of hydrogen for every one atom of helium, exactly the ratio observed by astronomers looking at the stars.

The idea was profound and exciting. But his thesis adviser had another twist to offer; he wanted to add renowned physicist Hans Bethe's name to the list of authors as a scientific pun: Alpher, Bethe and Gamow would be the alpha, beta and gamma of science. Bethe, who had nothing to do with the research, gamely agreed.

Word spread that the young Silver Spring resident had made a major scientific breakthrough. His thesis defense drew 300 spectators to GWU's auditorium, including prominent scientists and the press. Asked how long the whole process of primordial nucleosynthesis had taken, Dr. Alpher said about 300 seconds.

The next day, a six-paragraph article in The Washington Post was headlined: "World Began in 5 Minutes, New Theory." A Herblock cartoon showed an evil-looking atom bomb reading the headline, scratching its chin and pondering, "Five Minutes, Eh?"

Within months, Dr. Alpher next published, with Herman, a paper that said radiation from the big bang should still be in the universe, cooled to a temperature of 5 degrees Kelvin (about 450 degrees below zero Fahrenheit). But astronomers, skeptical of the big-bang theory in general, did not believe it could be measured and would not pursue it.

Stymied by the lack of enthusiasm, Dr. Alpher left Johns Hopkins in 1955 to join General Electric in Schenectady, N.Y. He joined the faculty at Union College in Schenectady in 1986. He retired in 2004.

Eventually, he did receive recognition for his achievements: the 1975 Magellanic Premium from the American Philosophical Society, the John Price Wetherill Medal from the Franklin Institute and the National Academy of Sciences' 1993 Henry Draper Medal. He was a fellow of the American Physical Society and the American Academy of Arts and Sciences.

His wife of 66 years, Louise Simons Alpher, died in 2004.

Survivors include two children, Victor Alpher of Austin and Harriet Lebetkin of Danbury, Conn.; and two grandchildren.