Beyond the God Particle, by Leon Lederman and Christopher Hill (Amherst, NY: Prometheus Books, 2013, ISBN hardcover, 978-1-61614-801-0; e-book, 978-1-61614-802-7) 325 pp. Hardcover, $24.95; e-book, $12.99.
In 1964, six physicists published three independent papers in the same issue of Physical Review Letters suggesting a way by which certain elementary particles gain mass. The process was dubbed the “Higgs mechanism” after just one of the authors, an unassuming British professor named Peter Higgs. The other authors deserve mention. They are Robert Brout (now deceased), François Englert, Gerry Guralnik, Dick Hagen, and Tom Kibble. In simplest terms, particles such as the electron and those responsible for the weak nuclear force, which provides the energy of the sun, are intrinsically massless but gain mass, that is, inertia, by colliding with particles called “Higgs bosons,” which fill the universe.
In 1993, Nobel laureate and Fermilab director Leon Lederman, with Dick Teresi, published a book titled The God Particle: If the Universe Is the Answer, What Is the Question? Lederman had used the phrase “God particle” to describe the Higgs boson in a lecture, partly as a joke. He is a great stand-up comedian with a mischievous smile that never leaves his face. However, Lederman was also partly serious in emphasizing the fundamental role of the Higgs particle, existing everywhere in space, sort of like a god, and providing for the masses of particles. Most physicists hated the name. Higgs winced at it, calling it aggrandizing and offensive. Lederman said he offended two groups of people: those who believe in God and those who don’t. But his publisher liked it (I am told that putting God in the title of a book helps its sales) and the media loved it.* In any case, the term never had anything to do with theology.
The God Particle was written, in part, to generate public support for the Superconducting Supercollider (SSC) that would seek to confirm, or deny, the existence of the Higgs boson. The Higgs had become an intrinsic ingredient of the highly successful standard model of elementary particles, which was developed in the 1970s, and it was the only element of the model that remained to be empirically tested. President Ronald Reagan had given his approval for the SSC and in 1991 construction had begun at the selected site, Waxahachie, Texas. The collider was to be a ring 87.1 kilometers around, and it would collide beams of protons together, each with energy 20 TeV (trillion electron-volts). However, in 1993, after three billion dollars had been spent and the tunnel for the ring was almost 30 percent complete, Congress balked at the twelve-billion-dollar estimated cost. Furthermore, not all the scientific community was behind it, so the project was cancelled. This event marked the beginning of a sharp decline in support for elementary particle physics in the United States that has continued to this day. Physics graduate students looked elsewhere for opportunities, and they still do.
Although many particle physics research facilities remain in operation all over the world, including the United States, the international CERN (European Organization for Nuclear Research) laboratory in Geneva has for many years been the largest accelerator site in the world. There the greatest scientific effort of all time was mounted to build the Large Hadron Collider (LHC). While the LHC is huge and still cost billions, it is smaller and cheaper than the SSC would have been, using an already existing tunnel “only” 27 kilometers long compared to 87.1 kilometers and “only” 14 TeV total collision energy compared to 40 TeV for the SSC. On July 4, 2012, CERN announced that two independent experiments involving thousands of scientists from seventy-nine countries had each detected highly significant signals in the mass range 125-126 GeV that were very likely the long-sought Higgs boson. On October 8, 2013, it was announced that Peter Higgs and François Englert had been awarded the 2013 Nobel Prize for Physics.
Lederman’s Beyond the God Particle, which looks at the next phase of exploration, written with theoretical physicist Christopher Hill, has something for everyone. A reader with no formal education in physics but a lively interest will be treated to the basics of particle acceleration and the structure of matter. The physics student will be brought up to date on the standard model of elementary particles and the role played by rare processes and neutrinos. The authors make a heroic but what I think is ultimately not very successful attempt to explain the Higgs mechanism by going deeper than the typical, oversimplified popular accounts. It’s really tough without the math.
Of special interest to old-time particle physicists such as myself, who worked at Fermilab, CERN, and other particle accelerators during a forty-year career in the field, the authors provide details on Project X at Fermilab, which is developing a wide range of new techniques for going beyond the Higgs boson to new physics (the authors drop the use of “God particle” early in the book, after explaining its origin). The techniques being considered by Project X do not just involve higher and higher energies but higher intensities at lower energies and other methods.
Especially gratifying to me personally is an emphasis on “long-baseline” neutrino experiments that send beams of neutrinos from accelerators through Earth to distant underground detectors. Back in the 1980s, I made a proposal presentation to a Fermilab program committee for such an experiment, but its time had not yet come. It now has. Today there are three operating long-baseline neutrino experiments, including one that sends neutrinos 450 miles from Fermilab to a mine in Minnesota. Part of Project X is LBNE, the Long-Baseline Neutrino Experiment, which will send a high-intensity beam of neutrinos eight hundred miles to the Homestake Mine in South Dakota, where neutrinos from the Sun were first observed by Ray Davis in the 1960s. Davis saw half as many as expected, and this finding remained controversial for many years. But it proved correct and was the first evidence that neutrinos “oscillate” from one type to another while in flight from a source to detector. It’s as if a pitcher tossed a baseball that changed into a golf ball on the way to home plate.
I played a small role in the verification of neutrino oscillations in 1998 by an experiment in a mine in Japan called “Super-Kamiokande.” This showed conclusively that neutrinos have very small but nonzero masses. Davis and the leader of Super-Kamiokande, Masatoshi Koshiba, shared the 2002 Nobel Prize for Physics.
The long-baseline neutrino experiments are designed to use this quantum-mechanical phenomenon to probe deeper into the forces of nature than is possible with any feasible colliding beam accelerator. One of the problems that is beginning to raise its head at the LHC is that no new phenomenon beyond the anticipated Higgs has yet been seen. It is hoped that that will change when the energy is doubled, but decades ago some reputable physicists were already predicting that a “desert” extends well beyond the LHC energy where no new physics will be found once the standard model is wrapped up. Surely some new physics has to be out there somewhere, but it may be beyond reach of any conceivable accelerators.
For example, one major question that is not answered by the standard model is why particles outnumber antiparticles by a factor of a billion in the universe. Neutrino long-baseline experiments may be able to test the explanation proposed in 1967 by the famous Russian physicist and political dissident, Andrei Sakharov, in which the natural symmetry between particles and antiparticles was spontaneously broken when th
e universe was very young.
Also, according to Lederman and Hill, Project X will not just concern itself with fundamental physics questions but will explore solutions to the problems of clean energy and nuclear waste. One new idea (to me) is “accelerator-driven subcritical reactors” that generate energy by the fission of lighter elements such as thorium without requiring a critical mass. (Although not mentioned in the book being reviewed, I would like to take this opportunity to promote another technology involving thorium that has been in our possession since 1945 and which holds the promise of solving the world’s energy problems for a thousand years. I won’t worry about what happens after that. This is the liquid fluoride thorium reactor [LFTR].** Such reactors would never lead to meltdowns such as Fukushima and Chernobyl. The only reason this specific reactor technology was dropped during the Nixon administration is that it has no military applications. You can really see why hawkish politicians, who are also fossil-fuel funded, object.)
Finally, scientists and science supporters will greatly appreciate Lederman and Hill’s impassioned case for the importance of basic science to society. They tell the probably apocryphal story of a visit to Michael Faraday’s lab by the Chancellor of the Exchequer, William Gladstone. Gladstone wanted to see where all this “wasteful” spending on electricity was going. Faraday supposedly responded, “I don’t know what good this will be, but one day you may tax it.”
One of the readers of my regular Huffington Post blog once asked me what use could the Higgs boson possibly have. I answered: How could Faraday have known to tell Gladstone that electricity would someday make it possible for teenagers to send written messages instantaneously to their friends all over the world with a small, hand-held device?
Lederman and Hill also remind us that in 1989 a young computer scientist working at CERN named Tim Berners-Lee proposed what he called a “distributed information system” to enable the lab’s scientists to handle the great amounts of data that were then coming in from its Proton Synchrotron accelerator. I don’t know who was the author, but in the early 1980s I used an early version of the program, involving now familiar “hyper-links,” to organize the data from a neutrino experiment with the fifteen-foot bubble chamber at Fermilab. The collaboration involved several universities with different computers and different analysis programs. I wrote to CERN, and they provided me with the program free of charge, including the cost of shipping a heavy magnetic tape from Geneva to Honolulu. No one had ever heard of software licensing in those days.
As is now legend, Berners-Lee’s program became the World Wide Web, a vital part of the Internet. Lederman and Hill call it “the greatest information revolution humanity has ever seen” and note that today it “garners many trillions of dollars worth of new gross domestic product per year for all the people on planet Earth.
Lederman and Hill also mention the inventions of a Polish CERN physicist (and World War II resistance hero) Georges Charpac, in particular the “multiwire proportional chamber,” that is now widely used in biology, radiology, and nuclear medicine. Charpac was awarded the 1992 Nobel Prize for Physics.
No one can predict what practical applications can come out of the basic scientific research being done today, but history shows that without basic science we can expect little human progress. The Internet and multiwire proportional chamber did not result from a direct application of particle physics, but when you have very talented and dedicated people working on uncovering the basic nature of the universe, you can expect just this sort of spin-off.
Lederman and Hill calculate, “If U.S. particle physics received a mere 0.01 percent (a hundredth of a penny on the dollar) of the tax revenue per year on the cash flow it [that is, European particle physics] has generated by inventing the World Wide Web, the Superconducting Supercollider would have been built in Waxahachie, it would have discovered the Higgs boson ten years ago, and we’d be well on to the next machines.”
Very seldom do I find a popular book on physics written for a general audience from which I learn anything. This was not the case with Beyond the God Particle, which contains much that is new to me. Of course, the authors were not writing for me, and their intended wider audience will find much more that is useful and worthwhile.
*Ian Sample, Massive: the Missing Particle That Sparked the Greatest Hunt in Science (New York: Basic Books, 2012).
**Richard Martin, Superfuel: Thorium, the Green Energy Source for the Future (New York: Palgrave Macmillan, 2012); see also Victor J. Stenger, God and the Atom: From Democritus to the Higgs Boson (Amherst, NY: Prometheus Books, 2013).