Tuesday, December 13, 2011

The Higgs-Boson God Particle Found


Genesis 1.1-5: The First Day

1In the beginning, God created the heavens and the earth. 2The earth was without form and void, and darkness was over the face of the deep. And the Spirit of God was hovering over the face of the waters.

3And God said, "Let there be light," and there was light. 4And God saw that the light was good. And God separated the light from the darkness. 5God called the light Day, and the darkness he called Night. And there was evening and there was morning, the first day.


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Scientists May Have Observed Elusive
Higgs Boson "God Particle"


Higgs boson, aka the "God particle," is trending as physicists at the CERN, which operates the Large Hadron Collider in Switzerland, announced they may have finally glimpsed the elusive elemental particle critical to our understanding of how the universe works. Named after Physicist Peter Higgs, the subatomic particle is seen as the lynchpin to explain what gives mass and gravity to all other particles, thus allowing matter to interact the way we observe it. The hunt for Higgs boson has been going on for decades. Scientists at the CERN say the latest evidence is not a definitive discovery but that the data is "exciting" and suggests that with further statistical analysis, they should know within a year if the theoretical Higgs boson actually exists.




The Guardian

Higgs boson: scientists close in on 'God particle'

Ian Sample, science correspondent guardian.co.uk

Discovery would rank among most important scientific advances in 100 years
and confirm how elementary particles get mass

Scientists are expected to announce they may have caught their first glimpse of the Higgs boson, a curious subatomic particle long thought to underpin the microscopic workings of nature.

Hundreds of physicists will crowd into a seminar room at Cern, the European particle physics laboratory near Geneva, on Tuesday, to hear the latest in the hunt for the particle, while thousands more are expected to watch online.

The Higgs boson, or so-called God particle, has become the most coveted prize in particle physics since it was postulated in the mid-1960s. Its discovery would rank among the most important scientific advances of the past 100 years and confirm how elementary particles get mass.

(FILES) This file picture taken on March
Higgs boson hunt – finding the so-called God particle has been a major goal for the
£10bn Large Hadron Collder. Photograph: Fabrice Coffrini/AFP/Getty Images

Scientists have been hunting the Higgs for more than 30 years with machines so large they are miles across and consume the power of a reasonable-sized town. While the results are unlikely to be conclusive – the hints of the particle could fade when the Large Hadron Collider (LHC) collects more data next year – they are understood to be the strongest evidence so far that the Higgs particle is there to be found.

Finding the Higgs boson has been a major goal for the £10bn LHC after a less powerful machine at Cern, the LEP, failed to find the missing particle before it was shut down in 2000. The hunt was joined by scientists at the Tevatron collider near Chicago, who will present their results early next year.

The Higgs boson is the signature particle of a theory published by six physicists within a few months of each other in 1964. Peter Higgs at Edinburgh University was the first to point out the theory called for the existence of the unusual, missing particle.

According to the theory, an invisible energy field fills the vacuum of space throughout the universe. When some particles move through the field they feel drag and gain weight as a result. Others, like particles of light, or photons, feel no drag at all and remain massless.

Without the field – or something to do its job – all fundamental particles would weigh nothing and hurtle around at the speed of light. That would spell disaster for the formation of familiar atoms in the early universe and rule out life as we know it.

While the field is thought to give mass to fundamental particles, including quarks and electrons (the particles that make up atoms) it accounts for only 1% or 2% of the weight of an atom itself, or any everyday object. That is because most mass comes from the energy that glues quarks together inside atoms.

To hunt for the Higgs boson, physicists at the LHC sift through showers of subatomic debris that spew out when protons collide in the machine at close to the speed of light. Most of the energy released in these microscopic fireballs is converted into well-known particles that are identified by the collider's giant detectors.

Occasionally, the collisions might create a Higgs boson, but it disintegrates immediately into more familiar particles. To find it, scientists must look for telltale "excesses" of particles that signify Higgs boson decays. They appear as bumps, or peaks, in the data.

If the rumoured glimpse of the Higgs boson turns into a formal sighting next year, it may be one of several Higgs particles outlined in a radical, but much studied theory of nature called supersymmetry. The theory, that every known type of particle has an undiscovered twin, is popular among many physicists because it explains how some forces of nature might have behaved as one in the early universe. Unifying the forces of nature was a feat that eluded Albert Einstein.



Science News


Has the Higgs Been Discovered?
Physicists Gear Up for Watershed Announcement

By Davide Castelvecchi | December 8, 2011 |88

Rumors are flying about a December 13 update on the search for the long-sought Higgs boson at Europe's Large Hadron Collider

Part of the LHC in Geneva
SMASHING RESULTS? Workers in front of part of the ATLAS detector
at the Large Hadron Collider, one of two experiments rumored to have seen
hints of  the elusive Higgs boson.Image: CERN/Claudia Marcelloni

The physics buzz reached a frenzy in the past few days over the announcement that the Large Hadron Collider in Geneva is planning to release what is widely expected to be tantalizing—although not conclusive—evidence for the existence of the Higgs boson, the elementary particle hypothesized to be the origin of the mass of all matter.

Many physicists have already swung into action, swapping rumors about the contents of the announcement and proposing grand ideas about what those rumors would mean, if true. "It's impossible to be excited enough," says Gordon Kane, a theoretical physicist at the University of Michigan at Ann Arbor.

The spokespersons of the collaborations using the cathedral-size ATLAS and CMS detectors to search for the Higgs boson and other phenomena at the 27-kilometer-circumference proton accelerator of the Large Hadron Collider (LHC) are scheduled to present updates December 13 based on analyses of the data collected to date. "There won't be a discovery announcement, but it does promise to be interesting," says James Gillies, spokesperson for CERN (European Organization for Nuclear Research), which hosts the LHC.

Joe Lykken, a theoretical physicist at Fermi National Accelerator Laboratory in Batavia, Ill., and a member of the CMS collaboration, says, "Whatever happens eventually with the Higgs, I think we'll look back on this meeting and say, 'This was the beginning of something.'" (As a CMS member, Lykken says he is not yet sure himself what results ATLAS would unveil; he is bound by his collaboration's rules not to reveal what CMS has in hand.)

[Click here for a lightly edited partial transcript of the interview with Lykken that Davide Castelvecchi conducted for this story.]

The talks were announced last week; true to form, the particle physics rumor mill shifted into high gear, and by the weekend multiple anonymous sources had leaked consistent information, according to several bloggers, including Peter Woit, Lubos Motl and Philip Gibbs. Both experiments are said to have seen evidence of the long-sought Higgs, pointing to a particle mass of around 125 billion electron volts, or 125 GeV. (125 billion electron volts is roughly the mass of 125 hydrogen atoms.) Such results would not constitute an ironclad discovery quite yet, being below the required "5 sigma," a measure of statistical reliability. But the two experiments are rumored to have seen signals of 2.5 sigma and 3.5 sigma, which together would give a strong hint. (Three sigmas would correspond to a one-in-370 chance of the finding being a statistical quirk, although in particle physics experiments it is not uncommon for 3-sigma results to vanish.)

Previous rounds of data analysis from the LHC as well as from its U.S. predecessor, Fermilab's Tevatron, had narrowed the Higgs mass range down to somewhere between 115 and 140 GeV. But the new announcement would constitute the first time that both LHC experiments had made a precise and consistent estimate of the mass.

Even before the data are out, theoretical physicists around the world are working out the possible implications. Some have pointed out that a value of 125 GeV would be good news for supersymmetry, a theory that predicts that each particle would have a heavier partner known as a superparticle (at least for particles within the framework of the Standard Model of particle physics, the currently accepted description of the subatomic world)." Most supersymmetric models put a Higgs below 140 [GeV] or so," says Matt Strassler of Rutgers University. Supersymmetry has long been a favorite candidate for extending the Standard Model, because it would answer numerous open questions, beginning with the nature of dark matter, the unseen mass that keeps galaxies rotating faster than they otherwise would.

But Kane, a longtime proponent of supersymmetry, makes a more ambitious statement. In a paper posted to the physics preprint site arXiv.org on December 5, he and his collaborators work not from supersymmetry but from an even more radical overhaul of physics: string theory. (String theory is itself an extension of supersymmetry.) Their calculations predict a Higgs mass between 122 and 129 GeV. "If it's in that range it's an incredible success for connecting string theory to the real world," Kane says. He says he is confident that the upcoming LHC announcements, if they pan out as predicted, will constitute evidence for string theory. "I don't think my wife will let us bet our house, but I'll come close," he says.

That Kane and his colleagues released their paper now that the Higgs mass has been—or is about to be—restricted to a particular range, will surely lead some physicists to charge that the new study constitutes not a prediction but a "postdiction." String theory critics have long claimed that the theory has so much flexibility that one can always tweak it to make it predict just about anything.

Moreover, whether string theory can make testable predictions at all has often been the subject of debate. "The trouble is, for all we know, there might be 10,000 other ways of starting with string theory and getting the same Higgs mass, and they may differ in other respects," Lykken cautions.

And when it comes to mass predictions, consistency does not necessarily mean validation, Strassler points out. "If the Higgs turns up at 125 GeV, that would also be consistent with the Standard Model with no supersymmetric particles and no hint of string theory," Strassler says.

For all the excitement, it is still quite possible that any preliminary whiff of the Higgs will later turn out to be a statistical fluke. After all, the CMS and ATLAS detectors cannot directly catch Higgs bosons; those particles would decay into other particles immediately after being created in the LHC's proton collisions. Instead, physicists must analyze the subatomic debris from the decays and reconstruct what happened. Thousands of collisions take place every second, and many of them generate signatures similar to those of the Higgs. "The reason why we don't know whether there's a Higgs yet has mostly to do with the fact that the Higgs boson's decays look like other kinds of physics," Lykken says. "So we need to understand the other kinds of physics enough. It's not just a question of statistics."

Whether next week's announcements pan out, experts say, it is only a matter of time before a final answer is known: Once the experiments have amassed enough data, they either will find the Higgs boson and understand its properties or they will conclusively demonstrate that it does not exist. "It's just a question of when it will happen," Lykken says. "It's not going to be a maybe-yes-maybe-no kind of answer."


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For More Information see Wikipedia - http://en.wikipedia.org/wiki/Higgs_boson


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CERN Announcement

Earlier this morning, CERN made a much-anticipated announcement about its progress in finding the elusive Higgs particle. Below, Brian Greene explains the significance of the news.


bg bwHere’s a summary of today’s announcement: The Large Hadron Collider (a 17-mile-long circular tunnel in which protons are sent whizzing around in opposite directions at just shy of light-speed, and directed into head-on collisions) has two mammoth detectors called ATLAS and CMS (each of which captures and analyzes particulate debris created by the proton–proton collisions). Two independent (and highly competitive) research teams, involving thousands of scientists, using each of these detectors have seen moderately convincing evidence that the elusive Higgs particle has been created in some of the proton–proton collisions.

This is a challenging experiment as the detectors can’t see the Higgs particle directly—it is a short-lived particle that quickly falls apart (decays)—but, rather, they infer its presence by seeing its decay products. (Watch here, as physicist and ATLAS researcher Monica Dunford explains this process of inferring new possible particles during the World Science Festival.) In particular, the equations show that when a Higgs particle decays, some fraction of the time two photons (particles of light) are produced. The researchers sift through a maelstrom of debris for these photons, but even then they need to ensure that the photons weren’t produced by some other, more mundane process. This painstaking work, aided by sophisticated computer analysis, now shows evidence of a Higgs particle that weighs about 126 times as much as a proton.

The researchers’ confidence in this result, while fairly strong, does not yet rise to the level at which a definitive discovery is claimed (there’s roughly a chance of a few in a thousand that the data is a statistical fluke, sort of like the chance of getting 8 to 9 heads in a row when you flip a coin; the protocol for claiming a definitive discovery is more like 1 in a million, similar to getting heads about 20 times in a row). But within the next few months, or surely within the next year, the teams should know whether or not they’ve found the Higgs particle.

For some background, here’s a short piece (about a minute long) I filmed giving an explanation of the Higgs idea—take a look if you have a moment. In the video, when I refer to a “molasses-like substance” that’s a metaphor for the “Higgs field”; the Higgs particle would be a tiny nugget of that field which the violent particle collisions at the Large Hadron Collider may have, roughly speaking, knocked loose.








Brian Greene and Lawrence Krauss on CERN’s Higgs Announcement
http://worldsciencefestival.com/videos/ask_brian_greene_and_lawrence_krauss_cerns_higgs_announcement?utm_source=Fb_BG&utm_medium=Wall&utm_campaign=Higgs

The Cosmos    higgs boson     large hadron collider    physics

About This Video

On the morning of December 13th, the European Organization for Nuclear Research (CERN) announced that its Large Hadron Collider had found evidence which leads them to believe that the elusive Higgs Boson may reside at the 126 gigaelectron volts(GeV) of energy with a confidence level of 2.8 sigma. A sigma of greater than 5 is required to announce the discovery of a new particle. World Science Festival co-founder Brian Greene was at Arizona State University at the time, and he met with theoretical physicist and WSF alum Lawrence Krauss in order to field some questions sent in about the Higgs Boson and the future of physics as we know it.






Eternal Inflation of a Cosmic Landscape
http://worldsciencefestival.com/videos/eternal_inflation_of_a_cosmic_landscape

2011.12.08

About This Video

The search for a unified theory of physics has led theorists far and wide for answers. String theory is a major contender in the race to find the unified theory, but there are things that it doesn’t explain. Surprisingly, the answers have been coming from cosmologists. Stanford University physicist Leonard Susskind explains how a vast energy landscape becomes populated with bubbles, each with their own complex landscapes.




How can one picture Eternal Inflation and Multiverses?
By thinking of it in terms of...

Bubbles within bubbles within bubbles in an infinite but discrete array
of primodial possibilities giving birth to more arrays of primodial possibilities.

In the end, we live in the kind of universe that can support the kind
of universe that we can live within.




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