Paul Charles William Davies AM (born 22 April 1946) is an English physicist, writer and broadcaster, a professor in Arizona State University and director of BEYOND: Center for Fundamental Concepts in Science.

He attended Woodhouse Grammar School and studied physics at University College London, gaining a Bachelor of Science degree with first-class honours in 1967.

His notable contributions are the so-called Fulling–Davies–Unruh effect,[4] according to which an observer accelerating through empty space will be subject to a bath of induced thermal radiation, and the Bunch–Davies vacuum state, often used as the basis for explaining the fluctuations in the cosmic microwave background left over from the Big Bang.

Davies has had a longstanding association with the problem of time's arrow, and has also identified the mystery of 'dark energy' as one of the most important issues facing fundamental science.

[5] Davies was also an early proponent of the theory that life on Earth may have come from Mars cocooned in rocks ejected by asteroid and comet impacts.

[9][10] Davies is an outreach investigator at Arizona State University's Center for Convergence of Physical Science and Cancer Biology.

"[14] The Edge Foundation presented a criticism of Davies' article written by Jerry Coyne, Nathan Myhrvold, Lawrence Krauss, Scott Atran, Sean Carroll, Jeremy Bernstein, PZ Myers, Lee Smolin, John Horgan, Alan Sokal and a response by Davies beginning "I was dismayed at how many of my detractors completely misunderstood what I had written.

"[15] While atheists Richard Dawkins[16] and Victor J. Stenger[17] have criticised Davies' public stance on science and religion, other commentators, including the John Templeton Foundation,[18] have praised his work.

"[21] He also made the statement, "Well, I would be astonished if this was the only arsenic-based organism on Earth and Felisa just happened to scrape it up from the bottom of Mono Lake on the first try, It's quite clear that it is the tip of an iceberg.