Physics, more than any other field, lured me into science journalism more than three decades ago. Physics represented a kind of scientific theology, an empirical, rational way of probing, if not solving, the mysteries of existence. Physicists were discerning resonances between the smallest and largest scales of reality and spinning out astonishing conjectures about our universe and even other universes.
My favorite scientific theologian was John Wheeler. Musing over how observation seems to influence the outcome of quantum experiments, Wheeler challenged conventional objectivity and materialism, and hinted that we humans might not be just a cosmic afterthought. We live in a “participatory” cosmos, he proposed, which emerges from the interaction of consciousness and the physical realm.
Wheeler popularized the anthropic principle, which purports to answer one of the deepest of all questions: Why are the laws of physics as we find them rather than some other way? What explains the precise strength of gravity and other constants of nature? The universe seems so, well, arbitrary. According to the anthropic principle, the universe must be as we observe it to be, because otherwise we wouldn’t be here to observe it.
Moreover, our universe might be one of many. The big-bang theory led Einstein, among others, to propose the oscillating-universe theory. Our cosmos will eventually stop expanding, collapse back in a “big crunch” and rebound in yet another big bang, which will in turn implode and be reborn, ad infinitum.
Quantum mechanics–which implies that a particle such as an electron, when we’re not looking at it, follows many paths–yielded an even weirder multiverse theory. In the late 1950s, Hugh Everett proposed that each particle pursues each possible path—in another universe.
What can physicists do to top these far-out visions? Not much, if books written over the past decade by leading physicist/popularizers are any guide. For the most part, they merely recycle the once-startling propositions of Wheeler and other precursors.
The old oscillating-universe theory is revived in Cycles of Time by Roger Penrose. In The Beginning of Infinity, David Deutsch dusts off Everett’s many-worlds hypothesis. And in his bestseller The Hidden Reality, Brian Greene extols all the varieties of multiverse, including the old idea that our universe may be a simulation running on the computer of an alien civilization.
These fantasies are not just stale. Increasingly, they strike me as escapist and even irresponsible, because they are so lacking in evidence. If theories are being passed off as science, shouldn’t they have at least a remote chance of being empirically corroborated? Otherwise, how do they differ from pseudoscientific ideas like intelligent design?
To recapture its fizz, physics desperately needs not new ideas but new facts. Ideally, physicists will stumble on something so astonishing that they abandon their pursuit of multiverses and other fantasies and return to reality.
In the late 1990s, astronomers studying supernovas deduced to their astonishment that the expansion of the universe is speeding up. But this discovery, the most exciting since I became a science writer, has not forced radical revisions of the big-bang paradigm. Similarly, the Higgs boson, detected a few years ago by the Large Hadron Collider, merely confirmed the standard model of particle physics. Ho hum.
Things have gotten so bad that physicists are openly fretting about the future of their field. In a recent TED Talk, “Have we reached the end of physics?”, Harry Cliff states that “for the first time in the history of science, we could be facing questions that we cannot answer, not because we don’t have the brains or technology, but because the laws of physics themselves forbid it.”
I still keep an eye on physics, but my go-to source for fizzy ideas now is research into the brain and mind. Science’s wildest frontier is inside our heads.
John Horgan directs the Stevens Center for Science Writings. This essay is adapted from one originally published in The Chronicle of Higher Education.
