Bernard d'Espagnat, a French physicist and philosopher of science whose work has focused on the philosophical implications of quantum theory, is the 2009 Templeton Prize winner. He is accepting the award this morning at a press conference (and live Web cast) at the United Nations Educational, Scientific, and Cultural Organization headquarters in Paris.
D'Espagnat, 87, was a senior physicist at CERN (where he helped form its theoretical physics group) and a longtime professor at the University of Paris-Orsay (now the University of Paris-Sud), where he was director of the Laboratory of Theoretical Physics and Elementary Particles from 1970 until his retirement in 1987. He is an emeritus professor of theoretical physics at the University of Paris-Sud.
From the mid-1960s to the early 1980s, he worked on foundational problems in physics and played a key role during the development of quantum mechanics, the theory that explains the rules that govern the behavior of atoms and molecules and predicts their interactions. (Specifically, he tested the "Bell's inequalities" theorem.) The impact of quantum theory was enormous: Pre-quantum physics—what we call "classical" physics—describes "reality as it really is," d'Espagnat explains, while quantum physics predicts what will be observed under certain circumstances.
Quantum physics reshaped our basic ideas about the nature of reality and challenged the way we thought about the world. Namely, d'Espagnat said in prepared remarks, "it is now clear that to strictly keep to the, apparently obvious, notion that all individual things really exist at some separate places in space whether we know about them or not is not fully compatible with our knowledge: It appears that a certain type of holism, not straightforwardly perceptible but hidden in the equations, must be taken into account."
D'Espagnat's idea is that a unifying, ultimate reality is "veiled" behind the things we perceive—"a ground of things" he calls it, that "lies so much beyond our concepts, be they familiar or mathematical, that the phenomena—those we directly perceive as well as those science describe—do not enable us to decipher it. On it they provide us with merely glimpses, and very vague ones at that."
Classical physicists, he said, seemed to think their job was to "explain everything by starting 'from the bottom up,' that is from elementary material components taken to be the fundamental entities and by showing that little by little they combine in such a way that finally the complex colorful world we see emerges." In their eyes, he explained, it was possible to reach "a knowledge of the ultimate nature of things, so that anything having to do with mystery was doomed to final elimination."
D'Espagnat sees things differently: What he calls the "ground of things" is "beyond conceptual knowledge, and mystery is not therefore something negative that has to be eliminated. On the contrary, it is one of its constitutive elements," he said.
"My own conception of present-day physics rather favors, as religions do, an explanation 'from the top,' that is ... grounded on a Being endowed with some mysterious unity and whose essence is not fully describable by means of conceptualized talk alone." And he's "convinced that those among our contemporaries who believe in a spiritual dimension of existence and live up to it are, when all is said, fully right."
The Templeton Prize, valued at about 1.42 million dollars, the largest annual monetary award given to an individual, celebrates someone who has made "an exceptional contribution to affirming life’s spiritual dimension." It will be officially awarded to d'Espagnat by Prince Philip, the Duke of Edinburgh, at a private ceremony at Buckingham Palace in London on May 5. —Heather Wax