物理學家發現釋放質量的"神"粒子(謠言).請學物理的幫助解釋一下
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Rumors in Physics Blogosphere Test Faith in \'God Particle\'
John Borland 06.18.07 | 2:00 AM
This illustration shows the simulated decay pattern of the Higgs boson, the much sought-after God particle, which researchers may or may not have found. For weeks, the physics world has been buzzing with rumors juicier -- at least in context -- than any Washington scandal: Researchers at Fermilab\'s Tevatron particle collider may have made one of the biggest scientific discoveries in decades, just months before a new European facility supplanted their position at the top of the field.
According to the rumors, researchers may have experimental results compatible with the discovery of a long-sought particle called the Higgs boson, sometimes dubbed the God particle, which is widely regarded as giving all other particles mass. Depending on the details, this could be a Nobel-level discovery, and could lead to a reexamination of much of today\'s physics.
Nevertheless, the blog-spread buzz is polarizing the physics community. The tension, and the ongoing silence from researchers in the know, says much about a field on the brink of changes that will shape research for decades to come.
There are a lot of ways that things can go wrong, said University of Padova\'s Tommaso Dorigo, who is also associated with Fermilab, but emphasized he has no direct knowledge of the data in question. Seeing something maybe worth another prize is an extraordinary claim, and would require extraordinary evidence.
The latest round of rumors began spreading in late May, when an anonymous commenter on Dorigo\'s blog alluded to unannounced, but potentially significant Tevatron results.
News quickly spread across the physics blogosphere. Others weighed in with details, all second- or third-hand, while some criticized the premature speculation. One scientist associated with the Fermilab team confirmed exasperatedly that a significant analysis was ongoing, and pleaded for calm.
But this kind of enthusiasm has happened before, often enough to lead to a kind of Higgs fatigue. Just a few months ago, researchers from the same facility drew eager attention after releasing data some felt could be a Higgs fingerprint. As usual, researchers haven\'t yet found confirmation.
The difference is, this time there\'s no data at all. No charts, no graphs, no researchers who have yet stepped forward to offer up the usual tentative interpretations.
In one sense, this simply represents the physics community\'s collision with the irrepressible nature of the blogosphere. Like politicians or Apple executives used to controlling information, research physicists are uncomfortable with leaks, preferring to analyze complicated, often deeply confusing data sets exhaustively before making claims.
We\'re delighted that there is this level of interest, but we can\'t say too strongly that there are some stringent criteria for being able to claim one has seen something in a particle physics experiment, said Fermilab spokeswoman Judy Jackson. There are many examples of things that people thought they have seen that have promptly disappeared.
Yet it\'s no wonder that the Fermilab researchers are taking extra care to dot every i and cross every microscopic t. Much of today\'s leading-edge particle physics research hangs on the hunt for this elusive Higgs particle, and if it has indeed shown up in Fermilab\'s data, the international physics community could be forced to reevaluate its theories and plans.
Rumors in Physics Blogosphere Test Faith in \'God Particle\'
John Borland 06.18.07 | 2:00 AM
The Higgs\' proposed role in both theory and the actual universe is critical. Without it, the Standard Model that has been exquisitely successful in describing and predicting the universe\'s menagerie of particles falls short of explaining why they -- and by extension we -- have any mass at all.
Researchers at today\'s particle accelerators, of which the U.S.-based Tevatron is the most powerful, have long hoped to find evidence of the Higgs. But most physicists have pinned their expectations on CERN\'s $8 billion Large Hadron Collider, or LHC, now being built in Switzerland, scheduled after recent delays to begin operations next spring.
The political fragility of this project, and of a similarly priced International Linear Collider still in the planning stages, have led some commentators to argue that finding the Higgs today would be disastrous for physics, undermining the rationale for the new facilities. Other researchers have called this nonsense, saying any discovery would open up new avenues of research possible only with the new colliders.
Many physicists discount the rumors strictly on experimental grounds, however.
Particle accelerator experiments inherently throw up what physicists call statistical fluctuations. Essentially, this means that in every hundred collisions, a mildly unusual blip in the data will show up. Every 1,000 instances, a more significant, but still meaningless blip will show, and so on.
According to the unconfirmed rumors, the Fermilab results show a fairly high degree of statistical significance, which -- if true -- is unusual. But even strong observations can wind up being explained as strong fluctuations, or fluctuations combined with modeling errors, not real breakthroughs, physicists note.
Other scientists note a historical trend: Researchers at experiments nearing the end of their lives often tend to uncover suggestive data, which argue for extending the experiments\' operation. In one recent example, work at CERN\'s Large Election-Positron collider, which had to be shut down to make way for the LHC, was extended in 2000 to investigate data that also raised hopes of a Higgs discovery.
Tevatron has plans and funding to work through the end of 2009, and thus is in no danger of immediate closure. But the opening of the LHC next year will undeniably shift the field\'s center of gravity to the European facility, away from Fermilab.
Whatever the final outcome, the weeks of rumors and response say more about the sociology of science than about science itself. The hard physics will come only when (and if) data is released, and the business of testing, interpreting and re-analyzing begins.
It\'s a lot like looking for an ivory-billed woodpecker, said University of Wisconsin-Madison physicist Dick Loveless, whose LHC experiment that’s due to start next year also stands a chance of finding the Higgs. Was it seen? Can you prove it?