Penzias

Arno A. Penzias, whose astronomical probes yielded incontrovertible evidence of a dynamic, evolving universe with a clear point of origin, confirming what became known as the Big Bang theory, died on Monday in San Francisco.

Until Dr. Penzias and Dr. Wilson published their observations, the Big Bang theory competed with the steady-state theory, which envisioned a more static, timeless expanse growing into infinite space, with new matter formed to fill the gaps.

Dr. Penzias and Dr. Wilson’s discovery finally settled the debate.

In 1961, Dr. Penzias joined AT&T’s Bell Laboratories in Holmdel, N.J., with the intention of using a radio telescope, which was being developed for satellite communications, to make cosmological measurements.

In 1964, while preparing the antenna to measure the properties of the Milky Way galaxy, Dr. Penzias and Dr. Wilson, another young radio astronomer who was new to Bell Labs, encountered a persistent, unexplained hiss of radio waves that seemed to come from everywhere in the sky, detected no matter which way the antenna was pointed.