![]() Physicists have never found any solid experimental data that contradict the Standard Model, and that’s a problem because they know it can’t be the final word on the nature of the physical universe. Its predictions continue to match experiments with uncanny precision. So far, the Standard Model remains practically impregnable. The LHC itself was conceived as a Standard Model destroyer. (Credit: Claudia Marcelloni de Oliveira/CERN)ĭespite their pride in the theory, Murayama and other physicists can hardly wait to punch it full of holes - their field advances only by tearing down the old and replacing it with something new and even more all-encompassing. Peter Higgs shares a Nobel Prize for proposing that his namesake particle and field explain how matter gains mass. “It’s an incredible success, and we physicists can boast about it.” “Pretty much everything is explained by the Standard Model,” says Hitoshi Murayama, a theoretical physicist at the University of California, Berkeley. With the discovery of the Higgs boson, physicists found the last missing piece of the Standard Model, an overarching theory that describes the universe in terms of a handful of particles and four fundamental forces. ![]() The discovery of the Higgs boson netted a Nobel Prize in 2013 for Higgs, who is now 86, and François Englert, 82, a physicist at the Free University of Brussels. Particles that we perceive as being heavy interact strongly with the Higgs field lighter particles interact more weakly. The universe, they said, is filled with an invisible field, now called the Higgs field, that interacts with all particles via one very special particle: the Higgs boson. Why are protons 2,000 times heavier than electrons, yet their charges are simply equal and opposite? Why do photons - particles of light - have no mass at all? And all the fundamental particles in nature have a seemingly random assortment of masses. Mass varies depending on how fast particles move protons zipping along at close to the speed of light, like those in the LHC, weigh more than protons at rest. Some properties of particles - the negative electric charge on an electron or the positive charge on a proton, for example - are intrinsic to the particle itself. Isn’t mass simply a given, a basic feature of matter? No, it turns out. The particle’s existence was first predicted 50 years ago by several physicists working independently, including Peter Higgs at the University of Edinburgh, as a solution to what had been one of the most vexing mysteries in physics: How do particles acquire mass?įor those of us who aren’t physicists, the question barely seems worth asking. On July 4, 2012, seven months before the machine’s hiatus, physicists announced they had discovered the particle that the $4.9 billion accelerator had been hunting: the Higgs boson. PART 1: The Greatest Machine of All TimeĮven before its upgrade, the LHC managed to shake up the physics world. Now physicists are anticipating a new era of discoveries from a machine that will dominate experimental particle physics for at least another two decades. “I called it the Little Hadron Collider,” says Maria Spiropulu, an experimental physicist at the California Institute of Technology, “because during its first run, it only operated at half-energy.” That changed in April when the accelerator fired up again after a two-year shutdown dedicated to nearly doubling the energy of its proton beams. The LHC started operating in 2008, yet for some physicists it only recently began to live up to its name. The project’s mission: to see what happens when protons collide at 99.99999 percent of the speed of light in a 17-mile-long circular tunnel. With about 1,200 giant superconducting magnets, multiple-ton detectors, a worldwide computing grid and a staff of thousands, the Large Hadron Collider is an international undertaking beyond the means of any single nation. On the outskirts of Geneva, Switzerland, some 300 feet underground, is the biggest, most complicated machine ever built.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |