God particle: What is the Higgs Particle and what it does?

Scientists at the CERN research centre have found a new subatomic particle that could be the Higgs boson, the basic building block of the universe. 

Joe Incandela, spokesman for one of the two teams hunting for the Higgs particle told an audience at CERN near Geneva: "This is a preliminary result, but we think it's very strong and very solid."

What is the Higgs Boson?

The Higgs is the last missing piece of the Standard Model, the theory that describes the basic building blocks of the universe. The other 11 particles predicted by the model have been found and finding the Higgs would validate the model. Ruling it out or finding something more exotic would force a rethink on how the universe is put together.

Scientists believe that in the first billionth of a second after the Big Bang, the universe was a gigantic soup of particles racing around at the speed of light without any mass to speak of. It was through their interaction with the Higgs field that they gained mass and eventually formed the universe.

The Higgs field is a theoretical and invisible energy field that pervades the whole cosmos. Some particles, like the photons that make up light, are not affected by it and therefore have no mass. Others are not so lucky and find it drags on them as porridge drags on a spoon.

Picture George Clooney (the particle) walking down a street with a gaggle of photographers (the Higgs field) clustered around him. An average guy on the same street (a photon) gets no attention from the paparazzi and gets on with his day. The Higgs particle is the signature of the field - an eyelash of one of the photographers.

The particle is theoretical, first posited in 1964 by six physicists, including Briton Peter Higgs.

The search for it only began in earnest in the 1980s, first in Fermilab's now mothballed Tevatron particle collider near Chicago and later in a similar machine at CERN, but most intensively since 2010 with the start-up of the European centre's Large Hadron Collider.

What is the Standard Model?

The Standard Model is to physics what the theory of evolution is to biology. It is the best explanation physicists have of how the building blocks of the universe are put together. It describes 12 fundamental particles, governed by four basic forces.

But the universe is a big place and the Standard Model only explains a small part of it. Scientists have spotted a gap between what we can see and what must be out there. That gap must be filled by something we don't fully understand, which they have dubbed 'dark matter'. Galaxies are also hurtling away from each other faster than the forces we know about suggest they should. This gap is filled by 'dark energy'. This poorly understood pair are believed to make up a whopping 96 percent of the mass and energy of the cosmos.

Confirming the Standard Model, or perhaps modifying it, would be a step towards the holy grail of physics - a 'theory of everything' that encompasses dark matter, dark energy and the force of gravity, which the Standard Model also does not explain. It could also shed light on even more esoteric ideas, such as the possibility of parallel universes.

CERN spokesman James Gillies has said that just as Albert Einstein's theories enveloped and built on the work of Isaac Newton, the work being done by the thousands of physicists at CERN has the potential to do the same to Einstein's work.

What is the Large Hadron Collider?

The Large Hadron Collider is the world's biggest and most powerful particle accelerator, a 27-km (17-mile) looped pipe that sits in a tunnel 100 metres underground on the Swiss/French border. It cost 3 billion euros to build.

Two beams of protons are fired in opposite directions around it before smashing into each other to create many millions of particle collisions every second in a recreation of the conditions a fraction of a second after the Big Bang, when the Higgs field is believed to have 'switched on'.

The vast amount of data produced is examined by banks of computers. Of all the trillions of collisions, very few are just right for revealing the Higgs particle. That makes the hunt for the Higgs slow, and progress incremental.

What is the Threshold for Proof?

To claim a discovery, scientists have set themselves a target for certainty that they call "5 sigma". This means that there is a probability of less than one in a million that their conclusions from the data harvested from the particle accelerator are the result of a statistical fluke.

The two teams hunting for the Higgs at CERN, called Atlas and CMS, now have twice the amount of data that allowed them to claim 'tantalising glimpses' of the Higgs at the end of last year and this could push their results beyond that threshold.

CERN experiments observe particle consistent with long-sought Higgs Boson

Geneva: One of the two independent teams at the world's biggest atom smasher said today that it has found strong evidence of a new subatomic particle that looks like the one believed to give all matter in the universe size and shape.

Here's what CERN had to say on the development:

At a seminar held at CERN today as a curtain raiser to the year's major particle physics conference, ICHEP2012 in Melbourne, the ATLAS and CMS experiments presented their latest preliminary results in the search for the long sought Higgs particle. Both experiments observe a new particle in the mass region around 125-126 Gev

"We observe in our data clear signs of a new particle, at the level of 5 sigma, in the mass region around 126 GeV. The outstanding performance of the LHC and ATLAS and the huge efforts of many people have brought us to this exciting stage," said ATLAS experiment spokesperson Fabiola Gianotti, "but a little more time is needed to prepare these results for publication."

"The results are preliminary but the 5 sigma signal at around 125 GeV we're seeing is dramatic. This is indeed a new particle. We know it must be a boson and it's the heaviest boson ever found," said CMS experiment spokesperson Joe Incandela. "The implications are very significant and it is precisely for this reason that we must be extremely diligent in all of our studies and cross-checks."

"It's hard not to get excited by these results," said CERN Research Director Sergio Bertolucci. " We stated last year that in 2012 we would either find a new Higgs-like particle or exclude the existence of the Standard Model Higgs. With all the necessary caution, it looks to me that we are at a branching point: the observation of this new particle indicates the path for the future towards a more detailed understanding of what we're seeing in the data."

The results presented today are labelled preliminary. They are based on data collected in 2011 and 2012, with the 2012 data still under analysis.  Publication of the analyses shown today is expected around the end of July. A more complete picture of today's observations will emerge later this year after the LHC provides the experiments with more data.

The next step will be to determine the precise nature of the particle and its significance for our understanding of the universe. Are its properties as expected for the long-sought Higgs boson, the final missing ingredient in the Standard Model of particle physics? Or is it something more exotic? The Standard Model describes the fundamental particles from which we, and every visible thing in the universe, are made, and the forces acting between them. All the matter that we can see, however, appears to be no more than about 4% of the total. A more exotic version of the Higgs particle could be a bridge to understanding the 96% of the universe that remains obscure.

"We have reached a milestone in our understanding of nature," said CERN Director General Rolf Heuer. "The discovery of a particle consistent with the Higgs boson opens the way to more detailed studies, requiring larger statistics, which will pin down the new particle's properties, and is likely to shed light on other mysteries of our universe."

Positive identification of the new particle's characteristics will take considerable time and data. But whatever form the Higgs particle takes, our knowledge of the fundamental structure of matter is about to take a major step forward.

A new particle could be Physics' Holy Grail

Aspen (Colorado): Physicists working at CERN's Large Hadron Collider said today that they had discovered a new particle that looks for all the world like the Higgs boson, a long sought particle that is a key to understanding why elementary particles have mass and indeed to the existence of diversity and life in the universe.

"I think we have it," said Rolf Heuer, the Director General of CERN in an interview from his office outside of Geneva. His words signaled what is probably the beginning of the end of the longest most expensive manhunt in the history of science and, if scientists are lucky, could lead to a new understanding of how the universe began. 

Dr Heuer and others said that it was too soon to know for sure whether the new particle, which weighs in at 125 billion electron volts, the heaviest subatomic particle yet, fits the simplest description given by the Standard Model, the theory that has ruled physics for the last half century, or whether it is an imposter, a single particle or even the first of many. The latter possibilities are particularly exciting to physicists since they could point the way to new deeper ideas, beyond the Standard Model, about the nature of reality.


Joe Incandela, of the University of California, Santa Barbara, and spokesperson for one of two groups reporting data, Wednesday called the discovery, " very, very significant. It's something that may, in the end, be one of the biggest observations of any new phenomena in our field in the last 30 or 40 years, going way back to the discovery of quarks, for example."

Here at the Aspen Center for Physics, a retreat for scientists that will celebrate its 50th birthday Saturday, bleary-eyed physicists watched their colleagues read off the results in a webcast from CERN. That was a scene that was duplicated in Melbourne, Australia, where physicists had gathered for a major conference, to Los Angeles to Chicago to Princeton, New York City, London, and beyond, everywhere that members of a curious species have dedicated their lives and fortunes to the search for their origins in a dark universe. 

DMK protest against Tamil Nadu govt: Kanimozhi, Stalin court arrest, 50,000 party cadres to follow

Chennai: Arterial roads in Chennai are blocked and traffic is being diverted in many places as DMK cadres are pouring out all over Tamil Nadu to court arrest as part of the opposition party's jail bharo or fill jails protest against what it calls the AIADMK's "repressive regime" and "political vendetta." Senior party leaders and about 50,000 DMK workers are reportedly protesting outside government offices in the state. 

Here is this fast-developing story in 10 points:

1) DMK chief M Karunanidhi's son MK Stalin and daughter Kanimozhi have courted arrest. Kanimozhi, in a bright red sari, smiled and waved as she was led away in a bus by policewomen.

2) Kanimozhi, who is out on bail in the 2G case, has taken permission of the court to join the agitation from Saidapet. Stalin, who is the party treasurer, courted arrest in his constituency Kolathur.

3) Speaking after courting arrest, Ms Kanimozhi blamed the AIADMK for "indulging in vindictive politics from day one". "This is DMK's answer to AIADMK's vendetta politics. DMK leaders are being arrested without any proof. This is not a moment for soul searching by DMK. This is time for soul searching by the public and the press," she said.

4) Other senior leaders will court arrest too in 22 locations in Chennai. Former Union Minister Dayanidi Maran will court arrest outside Chennai's Ezhilagam.

5) Mr Karunanidhi, who is 90 and is not participating in the protests, has reportedly instructed all party leaders not to seek bail when they are arrested. They are all expected to be released by this evening.

6) Traffic has been thrown asunder. Three arterial roads - Panagal Building in Saidapet that connects the Airport and Guindy Industrial estate to Mount Road, the DMS complex almost in the heart of Mount Road and the Ezhilagam and War Memorial along Radhakrishnan Road or the Marina Beach Road - were blocked from 9 am till noon. Traffic movement is however slowly resuming here now. Traffic has been diverted at Chennai's Kamarajar Road, Greenways Road and RA Puram. Traffic disruptions are also being reported from Arcot Road, Rangarajapuram, Nandanam and Saidapet.

7) Chief Minister J Jayalalithaa, the main target of the DMK's ire, is not in Chennai. She is away in Ooty.

8) Mr Karunanidhi said yesterday, "The "fill the jails" protest will be held in a great manner ... we are confident about it. The government is also confident about that." He added that around 50,000 party members had agreed to participate in the agitation that is being held to condemn the continuing arrests of former DMK ministers and other party members.

9) The last two years have been turbulent for the DMK. It lost the Assembly elections, key leaders like A Raja and Kanimozhi were put behind bars in the 2G case, and ever since the J Jayalalithaa-led AIADMK took over, many senior DMK leaders and hundreds of party workers have been put in jail on land grab charges.

10) The ruling AIADMK government denies the allegation of political vendetta made by the DMK and claims that all arrests have been made on the basis of genuine complaints.