The Search for
the God Particle
In July 2012, scientists analyzing data from the Large Hadron Collider on the Swiss-French border announced, “I think we have it.” “It” was evidence of the Higgs boson, sometimes called the God particle. You don’t have to be a particle physicist to understand the importance of the discovery: The Higgs boson, which is believed to impart mass to other particles, may help explain the mysteries of how our world came to be.
For decades physicists have been trying to determine why some particles have mass and others, such as the photons that make up light, do not. In 1964 British physicist Peter Higgs authored one of three separate papers that hypothesized the existence of some kind of cosmic field that imparts mass. Higgs theorized that the field consists of particles formed 13.7 billion years ago in the nanoseconds following the Big Bang, when a region of infinite mass density exploded, rapidly expanded and then cooled, and the universe sprang into existence. These particles, named Higgs bosons, attach to other particles that move through the field, giving them mass. The more Higgs bosons a particle attracts, the greater its mass becomes. The Higgs boson has been described as the “cosmic molasses” that binds the universe together. Without Higgs bosons, matter would zip around the universe at the speed of light, and there would be no stars, planets or life as we know it. To connote its importance, Nobel Prize–winning physicist Leon Lederman dubbed the Higgs boson the “God particle” in his and Dick Teresi’s 1993 book of that name. Lederman originally nicknamed the Higgs boson the “goddamn particle” for its confounding elusiveness.
To test the theory of the Higgs boson’s existence, scientists needed to replicate conditions as they were a billionth of a second after the Big Bang. To do so they developed the Large Hadron Collider, an enormous underground accelerator ring. The space inside it is a vacuum so completely devoid of matter that its overseers call it “the emptiest place in the solar system.” Trillions of hadrons (subatomic particles made up of quarks) are sent zipping around the collider in both directions, and the vacuum allows them to reach almost the speed of light. The racing particles, making 11,245 laps each second, collide at a rate of some 600 million times per second, the collisions generating temperatures 100,000 times hotter than those at the sun’s core. The energy is transmitted into new particles that include, if the “God particle” theory is correct, the Higgs boson. On July 4, 2012, two teams of about 3,000 physicists each, working separately on data from the collisions, announced they had detected evidence of a “Higgs-like” particle. In early 2013, having analyzed the results of 2,000 trillion collisions, the team further confirmed, “It is clear that we are dealing with a Higgs boson.”
The center of the universe for particle physics is 300 feet belowground in a gigantic tunnel, 17 miles in circumference, spanning the border between France and Switzerland near Geneva. The Large Hadron Collider, operated by the European Organization for Nuclear Research (CERN), is the world’s largest scientific instrument. In its vast chambers, scientists attempt to simulate the conditions that led to the Big Bang, when the universe was created. Superconductive electromagnets chilled to temperatures colder than those in outer space propel trillions of subatomic particles around the collider. When particles crash into one another, the energy released creates primordial fireballs that take us back to the first microseconds of the universe. Data from these collisions should reveal a wealth of fundamental truths about our world and how it works. They may answer questions about the nature of matter immediately following the Big Bang; the nature of dark matter and dark energy; whether extra dimensions exist in space; and why, if everything we know is made of matter, there is essentially no antimatter. Most tantalizing of all, perhaps, the collider experiments may open new realms of physics that do not exist even in theory.
In the latter part of the 20th century, particle physicists devised the Standard Model of the universe, sometimes called the “theory of almost everything.” According to the Standard Model, everything in the universe is made from 12 basic building blocks called fundamental particles, and these are governed by four fundamental forces: the strong force, the weak force, the electromagnetic force and the gravitational force. Peter Higgs added an essential ingredient to the Standard Model when he proposed the presence of the particles now known as Higgs bosons to explain why the Standard Model’s fundamental particles have mass. The mountains of data supplied by subatomic collisions inside the Large Hadron Collider seem to support Higgs’s theory, so the next step for physicists is to determine the precise nature of the particle and its significance in our understanding of the universe. The collider was shut down in early 2013 so its superconductive electromagnets could be refitted to create even more forceful collisions, which, it is expected, will reveal additional clues to the mysteries of particle physics. The two-year wait is a trifle considering the LHC re-creates conditions as they were nearly 14 billion years ago.
When scientists switched on the Large Hadron Collider in September 2008, a few naysayers were terrified of being zapped by cosmic rays or sucked into black holes. The largest machine on earth, designed to create trillions of subatomic explosions that unleash unimaginable amounts of energy, the LHC seems like something out of science fiction. Scientists have reassured the public that the collider is safe, noting much of what happens in the gigantic tunnel occurs naturally all the time. Cosmic rays (speeding streams of atomic nuclei), which the LHC re-creates under controlled conditions, are produced in space and continually bombard Earth at energies far exceeding those in the collider. Theoretically, cosmic rays produce enough energy to create black holes, but in reality they don’t, nor did the collider, which ran safely for three years before shutting down for a revamp in early 2013. And cosmic rays weren’t the most farfetched fear: The LHC had a malfunction in 2008, leading a couple of physicists to speculate that the particle’s discovery would prove catastrophic, so much so that unknown forces from the future had traveled back in time to derail the attempt to locate it. The LHC’s findings put such worries to rest.
Particle physics, which deals in the elementary particles that make up everything in existence, in itself does not have many practical applications. Some of the techniques developed to conduct its research, however, have expanded into other areas and touched the lives of many. Particle detectors have been outfitted for use in nuclear reactors to monitor plutonium levels and detect leaks, and similar technology scans cargo containers at ports. Superconductive wiring used in accelerators may one day replace less efficient cables for electricity transmission. In medicine, detectors used in particle physics research are the basis of positron emission tomography (the technology of PET scans), and the accelerators used for particle physics experimentation also produce X-rays, protons, neutrons and heavy ions used in sophisticated cancer therapies. Biomedical researchers use particle physics technology to decipher the structure of proteins in the search for more targeted drug therapies. But the most broadly used byproduct of particle physics is the World Wide Web: A scientist working at the headquarters of CERN (the operator of the Large Hadron Collider) in Switzerland developed the web in the early 1990s to enable researchers in labs around the world to share information with their colleagues quickly and effectively.