"Here at last!" With this unusual but understandable exuberance, the Royal Swedish Academy of Sciences announced today that it has awarded the 2013 Nobel Prize in Physics to François Englert and Peter Higgs. Almost a half century ago, Englert and Higgs independently proposed the existence of a particle—which came to be known as the Higgs boson--that helps confer mass to other particles. The Higgs boson was finally discovered last year by the Large Hadron Collider at CERN, the European Center for Nuclear Research.
The Higgs has long inspired mixed reactions. As I reported last year, some observers fear that the Higgs boson may represent the last gasp of particle physics. I quoted physicist-journalist Adrian Cho noting in Science that “even as physicists celebrate, the discovery raises worries among some that there may remain no new physics that can be discovered with the atom-smasher.” Nobel laureate Steven Weinberg told Cho: “My nightmare, and it’s not just me, but a lot of us [in particle physics], is that the LHC discovers the Higgs boson and nothing else… That would be like closing a door."
Most other coverage of today's Nobel Prize announcement will no doubt be celebratory and upbeat about the future of particle physics. So surely no one will mind if I reprise the glum perspective of the Higgs I have offered in previous posts.
The Higgs has long been a mixed blessing for particle physics. In the early 1990s, when physicists were pleading—ultimately in vain–with Congress not to cancel the Superconducting Supercollider, which was sucking up tax dollars faster than a black hole, the Nobel laureate Leon Lederman christened the Higgs "the God particle." This is scientific hype at its most outrageous. If the Higgs is the "God Particle," what should we call an even more fundamental particle, like a string? The Godhead Particle? The Mother of God Particle?
Lederman himself confessed that "the Goddamn Particle” might have been a better name for the Higgs, given how hard it had been to detect “and the expense it is causing.” A more fundamental problem is that discovering the Higgs would be a modest, even anti-climactic achievement, relative to the grand ambitions of theoretical physics. The Higgs would serve merely as the capstone of the Standard Model of particle physics, which describes the workings of electromagnetism and the strong and weak nuclear forces. The Standard Model, because it excludes gravity, is an incomplete account of reality; it is like a theory of human nature that excludes sex. As physicist Michio Kaku put it in 2011, the Standard Model is “rather ugly” and “a theory that only a mother could love.”
Our best theory of gravity is still general relativity, which does not mesh mathematically with the quantum field theories that comprise the Standard Model. Over the past few decades, theorists have become increasingly obsessed with finding a unified theory, a “theory of everything” that wraps all of nature’s forces into one tidy package. Hearing all the hoopla about the Higgs, the public might understandably assume that it represents a crucial step toward a unified theory–and perhaps at least tentative confirmation of the existence of strings, branes, hyperspaces, multiverses and all the other fantastical eidolons that Kaku, Stephen Hawking, Brian Greene and other unification enthusiasts tout in their bestsellers.
But the Higgs doesn’t take us any closer to a unified theory than climbing a tree would take me to the Moon. String theory, loop-space theory and other popular candidates for a unified theory postulate phenomena far too minuscule to be detected by any existing or even conceivable (except in a sci-fi way) experiment. Obtaining the kind of evidence of a string or loop that we have for, say, the top quark would require building an accelerator as big as the Milky Way.
Kaku asserted that finding the Higgs “is not enough. What is needed is a genuine theory of everything, which can simply and beautifully unify all the forces of the universe into a single coherent whole—a goal sought by Einstein for the last 30 years of his life.” He insisted that we are at “the beginning, not the end of physics. The adventure continues.” Maybe. But I’m not hopeful. Whether or not physicists find the Goddamn Particle, the quest for unification, which has given physics its glitter over the past half century, looks increasingly like a dead end.
Almost 10 years ago, I put my money where my mouth is. The Long Now Foundation, a nonprofit that encourages long-term thinking, asked a bunch of people to make bets about trends in science, technology and other realms of culture. I bet Kaku $1,000 that by the year 2020, “no one will have won a Nobel Prize for work on superstring theory, membrane theory or some other unified theory describing all the forces of nature.” (Lee “loop space” Smolin was my original counter-bettor but backed out at the last minute, the big chicken.)
Kaku and I each put up $1,000 in advance, which the Long Now Foundation keeps in escrow. If civilization–or more importantly, the Long Now Foundation–still exists in 2020, it will give $2,000 to a charity designated by me (the Nature Conservancy) or Kaku (National Peace Action). In defending my bet, I stated:
“The dream of a unified theory, which some evangelists call a ‘theory of everything,’ will never be entirely abandoned. But I predict that over the next twenty years, fewer smart young physicists will be attracted to an endeavor that has vanishingly little hope of an empirical payoff. Most physicists will come to accept that nature might not share our passion for unity. Physicists have already produced theories–Newtonian mechanics, quantum mechanics, general relativity, nonlinear dynamics–that work extraordinarily well in certain domains, and there is no reason why there should be a single theory that accounts for all the forces of nature. The quest for a unified theory will come to be seen not as a branch of science, which tells us about the real world, but as a kind of mathematical theology.”
I added, however—and this is both mawkish tripe and the truth–that "I would be delighted to lose this bet."
Image and caption copyright: CERN, http://cms.web.cern.ch/news/about-higgs-boson. Image credit: Lucas Taylor.