Do you geek out over the the light-sparkle-boom show we enjoy each Fourth of July? Our friends over at Boing Boing share the above chart posted by The Works, which shows us the chemicals that make each firework color.
The results are based on the full batch of data gathered at Fermilab's Tevatron experiment over the course of more than a decade, and Fermilab said the findings represented the "strongest indication to date for the long-sought Higgs particle" from the separate teams behind the Tevatron's CDF and DZero detectors.
"The Tevatron experiments accomplished the goals that we had set with this data sample," CDF co-spokesperson Rob Roser said in a news release about the revelation. "Our data strongly point toward the existence of the Higgs boson, but it will take results from the experiments at the Large Hadron Collider in Europe to establish a discovery."
Discovery of the Higgs boson is the top objective for the $10 billion Large Hadron Collider, which was started up almost four years ago. Physicists have theorized about the particle and its associated Higgs field for four decades, working it in as a key part of the Standard Model, one of physics' most successful theories. The Higgs field is thought to be the mechanism that imparts mass to some particles while leaving other particles massless. What's more, the Higgs mechanism could serve as a gateway for going beyond the Standard Model and exploring way-out concepts such as supersymmetry and extra dimensions.
No wonder, then, that Nobel-winning Fermilab physicist Leon Lederman dubbed it "the God Particle" almost two decades ago. (Today, most physicists wish he hadn't.)
Fermilab via AFP - Getty Images
The 4-mile-round (6.4-kilometer-round) Tevatron accelerator was shut down last year, but researchers have just released what they say is their final analysis of data from the Tevatron experiments relating to the search for the Higgs boson.
Over the past year, results from Fermilab in Illinois as well as from the LHC on the French-Swiss border have focused in on a "bump" of anomalous data, hinting at an unknown particle with a mass of 125 billion electron volts, or 125 GeV. Two big questions have been hanging in the air: How precisely can the mass be determined? And how sure can the scientists be that what they're seeing is real, rather than merely a fluke in the data?
The Fermilab teams' almost-final answer is that a particle like the Higgs boson can lurk only in the area between 115 and 135 GeV, and they say there's just a 1-in-550 chance that the bump they're seeing is a random fluctuation. Another way of expressing the statistical confidence in the results is to say that it's at the 2.9-sigma level in the bottom-quark decay mode, and 2.5 sigma overall.
That level falls just short of the 3-sigma standard that physicists have been using for "strong evidence" of a subatomic particle's existence, and far short of the 5-sigma standard for "discovery." The 5-sigma level is equivalent to 99.99994 percent confidence. This is why Roser said actually establishing a discovery will have to be up to the LHC.
At least an almost-discovery As it happens, Europe's CERN particle-physics center has scheduled an announcement about the LHC's search on Wednesday, and for the past couple of weeks, onlookers have been wondering whether this will mark the true 5-sigma discovery of the Higgs boson. Last December, the teams behind the LHC's ATLAS and CMS detectors reported that they saw "tantalizing hints" of the Higgs at 125 GeV, with confidence levels of 3.6 sigma for ATLAS and 2.6 sigma for CMS.
Since that time, the detectors have doubled the amount of data collected, and the energy level for the LHC's collisions has ramped up to four times what was achievable at Fermilab's Tevatron. That has raised expectations that the LHC's results will come close to or even exceed the 5-sigma confidence standard, depending on how Wednesday's announcement is spun.
A graphic from Fermilab shows the "bump" that hints at the existence of the Higgs boson in a mass region from 115 to 135 GeV.
Advance indications suggest that the ATLAS and CMS teams both have higher confidence that they're really seeing a particle matching the Higgs boson's description — in the range of 4.5 to 5 sigma, according to Nature. Some of the advance rumblings suggest that the results from the two detectors would have to be combined to get past 5 — but CERN says that particular statistical twist won't figure into this week's announcement.
"Combining the data from two experiments is a complex task, which is why it takes time, and why no combination will be presented on Wednesday," CERN spokesman James Gillies told The Associated Press.
Even if one detector — say, ATLAS — were to get past 5, some physicists might still question the results. After all, the researchers who reported clocking neutrinos at speeds faster than light were pretty sure of their results, too, until they found a flaw in their fiber-optic timing system. But if the findings are as solid as the latest reports suggest, all this hand-wringing over the technical definition of a discovery may be a merely academic matter.
"I agree that any reasonable outside observer would say, ''It looks like a discovery,'" CERN physicist John Ellis told AP. "We've discovered something which is consistent with being a Higgs."
The Large Hadron Collider is continuing to run, and ATLAS and CMS are continuing to collect data. Even if the results being announced this week turn out to be merely an almost-discovery, the matter will certainly be settled by the end of the year, as predicted.
After the discovery Discovering the Higgs boson, or something like it, would just be the start of the real work to be conducted at the LHC: Is the Higgs mechanism totally in sync with what's predicted by the Standard Model? How does particle mass arise in the Higgs field? Are there any anomalous trails that could be followed to new frontiers in physics? This is where the results from Fermilab's Tevatron could come into play again.
Researchers at the LHC and the Tevatron can't detect the Higgs boson directly. Instead, they check a number of pathways by which the particle decays into other particles that can be detected — two photons, for example, or a pair of bottom quarks. To nail down the particle's characteristics completely, observations will have to be analyzed from multiple pathways.
Fermilab scientist Don Lincoln describes the nature of the Higgs boson.
"Being able to see it decaying into photons, and seeing it also in bottom quarks gives us some confidence that it's the Standard Model Higgs — and not some cousin particle that's similar to, but different from what the Standard Model predicts," Fermilab's Lincoln said. "Or, if you want to be terribly perverse, it could be some particle we haven't seen before, but not the Higgs at all."
If the LHC reports a discovery at the 125-GeV mass level, that would provide a new focus for Fermilab. "Once it's established that there's something to look at, we'll be able to retool the analyses to try to work out the question of what it is we're seeing," Lincoln said. Knowing for sure that there's something actually there, at 125 GeV, will allow physicists to fine-tune their analytical tools.
Fermilab shut down the Tevatron almost a year ago, so no new data can be collected at that collider. But the Tevatron data, when used in combination with the data that will continue to flood from the LHC, could still contribute to solving some of the deepest questions in physics. "The story is not over," Lincoln said.
The big story on July 4 Here are some websites to watch leading up to Wednesday's big reveal:
CERN webcast: Latest update in the search for the Higgs, with seminar at 3 a.m. ET and news conference at 5 a.m. ET Wednesday.
ViXra.org: Physicist Philip Gibbs blogs about boson buzz.
Richard Leakey predicts skepticism over evolution will soon be history.
Not that the avowed atheist has any doubts himself.
Sometime in the next 15 to 30 years, the Kenyan-born paleoanthropologist expects scientific discoveries will have accelerated to the point that "even the skeptics can accept it."
"If you get to the stage where you can persuade people on the evidence, that it's solid, that we are all African, that color is superficial, that stages of development of culture are all interactive," Leakey says, "then I think we have a chance of a world that will respond better to global challenges."
Leakey, a professor at Stony Brook University on Long Island, recently spent several weeks in New York promoting the Turkana Basin Institute in Kenya. The institute, where Leakey spends most of his time, welcomes researchers and scientists from around the world dedicated to unearthing the origins of mankind in an area rich with fossils.
His friend, Paul Simon, performed at a May 2 fundraiser for the institute in Manhattan that collected more than $2 million. A National Geographic documentary on his work at Turkana aired this month on public television.
Now 67, Leakey is the son of the late Louis and Mary Leakey and conducts research with his wife, Meave, and daughter, Louise. The family claims to have unearthed "much of the existing fossil evidence for human evolution."
On the eve of his return to Africa earlier this week, Leakey spoke to The Associated Press in New York City about the past and the future.
"If you look back, the thing that strikes you, if you've got any sensitivity, is that extinction is the most common phenomena," Leakey says. "Extinction is always driven by environmental change. Environmental change is always driven by climate change. Man accelerated, if not created, planet change phenomena; I think we have to recognize that the future is by no means a very rosy one."
Any hope for mankind's future, he insists, rests on accepting existing scientific evidence of its past.
"If we're spreading out across the world from centers like Europe and America that evolution is nonsense and science is nonsense, how do you combat new pathogens, how do you combat new strains of disease that are evolving in the environment?" he asked.
"If you don't like the word evolution, I don't care what you call it, but life has changed. You can lay out all the fossils that have been collected and establish lineages that even a fool could work up. So the question is why, how does this happen? It's not covered by Genesis. There's no explanation for this change going back 500 million years in any book I've read from the lips of any God."
Leakey insists he has no animosity toward religion.
"If you tell me, well, people really need a faith ... I understand that," he said.
"I see no reason why you shouldn't go through your life thinking if you're a good citizen, you'll get a better future in the afterlife ...."
Leakey began his work searching for fossils in the mid-1960s. His team unearthed a nearly complete 1.6-million-year-old skeleton in 1984 that became known as "Turkana Boy," the first known early human with long legs, short arms and a tall stature.
In the late 1980s, Leakey began a career in government service in Kenya, heading the Kenya Wildlife Service. He led the quest to protect elephants from poachers who were killing the animals at an alarming rate in order to harvest their valuable ivory tusks. He gathered 12 tons of confiscated ivory in Nairobi National Park and set it afire in a 1989 demonstration that attracted worldwide headlines.
In 1993, Leakey crashed a small propeller-driven plane; his lower legs were later amputated and he now gets around on artificial limbs. There were suspicions the plane had been sabotaged by his political enemies, but it was never proven.
About a decade ago, he visited Stony Brook University on eastern Long Island, a part of the State University of New York, as a guest lecturer. Then-President Shirley Strum Kenny began lobbying Leakey to join the faculty. It was a process that took about two years; he relented after returning to the campus to accept an honorary degree.
Kenny convinced him that he could remain in Kenya most of the time, where Stony Brook anthropology students could visit and learn about his work. And the college founded in 1957 would benefit from the gravitas of such a noted professor on its faculty.
"It was much easier to work with a new university that didn't have a 200-year-old image where it was so set in its ways like some of the Ivy League schools that you couldn't really change what they did and what they thought," he said.
Earlier this month, Paul Simon performed at a benefit dinner for the Turkana Basin Institute. IMAX CEO Rich Gelfond and his wife, Peggy Bonapace Gelfond, and billionaire hedge fund investor Jim Simons and his wife, Marilyn, were among those attending the exclusive show in Manhattan's Chelsea neighborhood.
Simon agreed to allow his music to be performed on the National Geographic documentary airing on PBS and donated an autographed guitar at the fundraiser that sold for nearly $20,000.
Leakey, who clearly cherishes investigating the past, is less optimistic about the future.
"We may be on the cusp of some very real disasters that have nothing to do with whether the elephant survives, or a cheetah survives, but if we survive."