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US experiment hints at 'multiple God particles' everynametaken Send a noteboard - 15/06/2010 04:04:14 AM
There may be multiple versions of the elusive "God particle" - or Higgs boson - according to a new study.

Finding the Higgs is the primary aim of the £6bn ($10bn) Large Hadron Collider (LHC) experiment near Geneva.

But recent results from the LHC's US rival suggest physicists could be hunting five particles, not one.

The data may point to new laws of physics beyond the current accepted theory - known as the Standard Model.

The Higgs boson's nickname comes from its importance to the Standard Model; it is the sub-atomic particle which explains why all other particles have mass.

However, despite decades trying, no one, so far, has detected it.

The idea of multiple Higgs bosons is supported by results gathered by the DZero experiment at the Tevatron particle accelerator, operated by Fermilab in Illinois, US.

DZero is designed to shed light on why the world around us is composed of normal matter and not its shadowy opposite: anti-matter.

Researchers working on the experiment observed collisions of protons and anti-protons in the Tevatron.

The collisions produced pairs of matter particles slightly more often than they yielded anti-matter particles.

The results showed a 1% difference in the production of pairs of muon (matter) particles and pairs of anti-muons (anti-matter particles) in these high-energy collisions.

Physicists had already seen such differences - known as "CP violation", but these effects were small compared to those seen by the DZero experiment.

The DZero results showed much more significant "asymmetry" of matter and anti-matter - beyond what could be explained by the Standard Model.

Bogdan Dobrescu, Adam Martin and Patrick J Fox from Fermilab say this large asymmetry effect can be accounted for by the existence of multiple Higgs bosons.

They say the data point to five Higgs bosons with similar masses but different electric charges.

Three would have a neutral charge and one each would have a negative and positive electric charge. This is known as the two-Higgs doublet model.

Dr Martin told BBC News that the two-Higgs doublet could explain the results seen by the DZero team whilst keeping much of the Standard Model intact.

"In models with an extra Higgs doublet, it's easy to have large new physics effects like this DZero result," he explained.

"What's difficult is to have those large effects without damaging anything else that we have already measured."

Dr Martin explained that there were other possible interpretations for the DZero result.

But he added: "The Standard Model fits just about every test we've thrown at it. To fit in a new effect in one particular place is not easy."

Developed in the 1970s, the Standard Model incorporated all that was then known about the interactions of sub-atomic particles.
Stepping stone

But today, many physicists regard it as incomplete, a mere stepping stone to something else.

The Standard Model cannot explain the best known of the so-called four fundamental forces: gravity; and it describes only ordinary matter, not the dark matter which makes up some 25% of the Universe.

The Standard Model only has one Higgs "doublet". Although we tend to think of the Higgs boson as one particle, it actually comes in a package of four, explained Dr Martin.

"In the Standard Model, you only see one of them becuase the other three are absorbed into [other parts of the scheme] such as the W and the Z bosons. There's only one left," he told BBC News.

"So if you want to add another Higgs doublet - you actually have to add four more particles."

The two-Higgs doublet model also ties in with a theory in particle physics known as supersymmetry.

Supersymmetry represents an extension to the Standard Model, in which each particle in the scheme has a more massive "shadow" partner particle.

But so far, physicists have lacked experimental evidence for the existence of these more massive particles.

Evidence for the Higgs and for supersymmetry could be uncovered by the LHC, the world's most powerful "atom smasher" which is housed 100m under the French-Swiss border.

The researchers have published the latest DZero study on the pre-print server arXiv.org; the results were reported by Symmetry magazine.

A physicist I am not but it sounds pretty cool to me. :P
But wine was the great assassin of both tradition and propriety...
-Brandon Sanderson, The Way of Kings
bbc
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US experiment hints at 'multiple God particles' - 15/06/2010 04:04:14 AM 697 Views
- 15/06/2010 04:11:11 AM 341 Views
this has always bothered me about particle physicists.... - 15/06/2010 05:32:26 AM 350 Views
Down with particle-of-the-gaps thinking! - 15/06/2010 05:38:20 AM 340 Views
Yeah, always been my problem, too. - 15/06/2010 05:44:30 AM 292 Views
Lederman wanted to call it "the goddamn particle," but the publisher wouldn't let him. - 15/06/2010 06:26:56 AM 314 Views
Well, we've been pretty bad at name stuff - 15/06/2010 08:52:09 AM 320 Views
"Giant radiating dyke swarms"?!!! - 15/06/2010 05:57:11 PM 317 Views
Oh, yes, and it's often accompanied by Dickite - 15/06/2010 06:18:35 PM 308 Views
This I can believe. - 15/06/2010 06:02:37 PM 260 Views
It's more than a few right answers. - 15/06/2010 06:26:35 AM 437 Views
As a physicist... - 15/06/2010 06:13:01 AM 436 Views
Cool. - 16/06/2010 01:01:34 PM 356 Views
I feel ya! *NM* - 17/06/2010 12:18:30 AM 205 Views
As a physicist, I find this quite interesting. - 16/06/2010 09:08:15 PM 437 Views
Not quite. - 16/06/2010 09:57:18 PM 422 Views
Re: Not quite. - 16/06/2010 10:22:14 PM 433 Views
Nerds! - 17/06/2010 12:19:57 AM 260 Views
Re: Not quite. - 17/06/2010 12:45:06 AM 489 Views
Re: Not quite. - 17/06/2010 08:23:10 AM 415 Views
Eight minus three is five - 17/06/2010 09:19:46 AM 237 Views

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