Photo of Gregory Breit

Gregory Breit

  • National Medal of Science
  • Physical Sciences

For pioneering contributions to the theoretical understanding of nuclear structure and particle dynamics, for highly significant work in atomic and ionospheric physics, and for the inspiration he has given to several generations of American physicists.

During the hydrogen bomb’s development, scientists worried the blast might be powerful enough to set off a runaway chain reaction.

Such a phenomenon could ignite a global explosion, destroying all life on Earth. Officials with the Manhattan project – America’s undercover operation to build nuclear weapons – employed Gregory Breit to ensure the atomic bomb’s obliteration wouldn’t extend beyond its intended target.

The Russian scientist was already well-versed in the physics of Earth’s atmosphere, having discovered the ionosphere earlier in his career. The atmospheric layer, located about 50 miles above the Earth’s surface, contains densely-arranged ions and electrons that are capable of reflecting radio signals. Breit’s calculations eased minds, proving that a runaway reaction from the H-bomb was unlikely.

Through his research, he also co-developed the resonance theory of nuclear reactions, which states that every object has different vibration frequencies. The principle later helped the Navy develop radar and sonar to spot undersea mines.