Could the Nobel Prize for the “divine particle” be the last gasp for particle physics?
“Finally here!” 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. Nearly half a century ago, Englert and Higgs independently proposed the existence of a particle, known as the Higgs boson, which helps to impart 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 represents the last gasp of particle physics. I quoted physicist-journalist Adrian Cho noting in Science that “even as physicists celebrate, the discovery raises concerns among some that there may not be any new physics left that can be discovered with the atom breaker”. 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… It would be like closing a door.”
Most other news stories about today’s Nobel Prize announcement will no doubt be celebratory and optimistic about the future of particle physics. So no one will care if I go back to the grim Higgs perspective I’ve offered in previous articles.
The Higgs has long been a mixed blessing for particle physics. In the early 1990s, as physicists pleaded – ultimately unsuccessfully – with Congress not to cancel the superconducting supercollider, which was sucking up taxpayers’ money faster than a black hole, Nobel laureate Leon Lederman dubbed 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 divine particle? The Particle of the Mother of God?
Lederman himself confessed that “the goddamn particle” might have been a better name for the Higgs, given how difficult it had been to detect “and the expense it entails”. A more fundamental problem is that the discovery of the Higgs would be a modest, if not anti-climax, achievement compared to the grand ambitions of theoretical physics. The Higgs would only serve as the cornerstone of the Standard Model of particle physics, which describes how electromagnetism works and the strong and weak nuclear forces. The Standard Model, because it excludes gravity, is an incomplete account of reality; it’s like a theory of human nature that excludes sex. As physicist Michio Kaku said in 2011, the Standard Model is “pretty ugly” and “a theory that only a mother could love”.
Our best theory of gravity remains general relativity, which does not correspond mathematically to the quantum field theories that make up the Standard Model. In recent decades, theorists have become increasingly obsessed with finding a unified theory, a “theory of everything” that encompasses all the forces of nature into one tidy whole. Hearing all the hype around the Higgs, the public might naturally assume that it represents a crucial step towards a unified theory – and perhaps at least tentative confirmation of the existence of strings, branes, hyperspaces, multiverse and all the other fantastic eidolons that Kaku, Stephen Hawking, Brian Greene and other unification enthusiasts tout their bestsellers.
But the Higgs doesn’t get us any closer to a unified theory than climbing a tree would get me to the moon. String theory, loop space theory, and other popular candidates for a unified theory postulate phenomena far too minute to be detected by any existing or even imaginable experiment (except in the realm of science fiction) . To get the kind of evidence for a chain or a 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 true theory of everything, which can simply and beautifully unify all the forces of the universe into one cohesive whole – one goal researched by Einstein over the last 30 years of his life. He insisted that we are “at the beginning, not the end of physics. The adventure continues. Perhaps. But I have not Whether physicists find the goddamn particle or not, the quest for unification that has given physics its brilliance 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 non-profit organization that encourages long-term thinking, asked a group of people to bet on trends in science, technology, and other areas of culture. I bet Kaku $1,000 that by 2020, “no one will have won a Nobel Prize for their 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 but backed out at the last minute, the big chicken.)
Kaku and I each bet $1,000 up front, which the Long Now Foundation is holding in escrow. If Civilization – or more importantly, the Long Now Foundation – still exists in 2020, it will donate $2,000 to a charity designated by me (the Nature Conservancy) or Kaku (National Peace Action). To defend my bet, I said:
“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 a company that has very little hope of empirical gain. Most physicists will eventually accept that nature may 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 areas, and there is no reason for there to be a single theory that accounts for all the forces of nature. The quest for a unified theory will no longer be seen as a branch of science, which tells us about the real world, but as a kind of mathematical theology.
However, I added—and this is both cheeky and true—that “I’d be happy to lose that bet.”
Image and caption copyright: CERN, http://cms.web.cern.ch/news/about-higgs-boson. Image credit: Lucas Taylor.