Higgs Boson: It is a type of elementary particle within the Standard Model of particle physics. European Organization for Nuclear Research (CERN) scientists reporting from the Large Hadron Collider (LHC) have claimed the discovery of a new particle consistent with the Higgs boson.
The Higgs field has been described as a kind of cosmic “treacle” spread through the universe. According to Prof Higgs’s 1964 theory, the field interacts with the tiny particles that make up atoms, and weighs them down so that they do not simply whizz around space at the speed of light.
But in the half-century following the theory, produced independently by the six scientists within a few months of each other, nobody has been able to prove that the Higgs Field really exists.
Scientists have been looking for the Higgs since the 1960s, but the search began in earnest more than 20 years ago with early experiments at Cern in Europe and Fermilab in the US.
After a quest spanning nearly half a century, physicists said they had found a new sub-atomic particle consistent with the elusive Higgs which is believed to confer mass. Rousing cheers and a standing ovation erupted at the European Organisation for Nuclear Research (CERN) after scientists presented astonishing new data in their search for the mysterious particle.
On 4th July 2012, the two main experiments at the LHC (ATLAS and CMS) both reported independently the confirmed existence of a previously unknown particle with a mass of about 125 GeV/c2 (about 133 proton masses, on the order of 10-25 kg), which is “consistent with the Higgs boson” and widely believed to be the Higgs boson. They acknowledged that further work would be needed to confirm that it is indeed the Higgs boson and not some other previously unknown particle (meaning that it has the theoretically predicted properties of the Higgs boson) and, if so, to determine which version of the Standard Model it best supports.
The Standard Model and the Higgs boson:
• The Standard Model is the simplest set of ingredients – elementary particles – needed to make up the world we see in the heavens and in the laboratory
• Quarks combine together to make, for example, the proton and neutron – which make up the nuclei of atoms today – though more exotic combinations were around in the Universe’s early days
• Leptons come in charged and uncharged versions; electrons – the most familiar charged lepton – together with quarks make up all the matter we can see; the uncharged leptons are neutrinos, which rarely interact with matter
• The “force carriers” are particles whose movements are observed as familiar forces such as those behind electricity and light (electromagnetism) and radioactive decay (the weak nuclear force)
• The Higgs boson came about because although the Standard Model holds together neatly, nothing requires the particles to have mass; for a fuller theory, the Higgs – or something else – must fill in that gap
About 13.7 billion years ago, the Big Bang gave birth to the universe and caused an outburst of massless particles and radiation energy. Scientists think that fractions of a second later, part of the radiation energy congealed into the Higgs field.
When the universe began to cool, particles acquired mass from the Higgs field, slowed down and began to bunch up to form composite particles and, eventually, atoms.
Interesting Question & Answers from Belfasttelegraph:
Q. What exactly is the “Higgs boson”?
A. A boson is a type of subatomic particle that imparts a force. The Higgs boson was postulated in the early 1960s by Professor Peter Higgs of Edinburgh University who suggested that its existence could explain why matter, from atoms to planets, have mass rather than float around the Universe without any mass, like photons of light.
Q How is the Higgs boson related to the Big Bang?
A About 13.7bn years ago the Big Bang gave birth to the universe and caused an outburst of massless particles and radiation energy.
Scientists think that fractions of a second later, part of the radiation energy congealed into the Higgs field. When the universe began to cool, particles acquired mass from the Higgs field, slowed down and began to bunch up to form composite particles and, eventually, atoms. Conditions present a billionth of a second after the Big Bang are recreated in the Large Hadron Collider particle accelerator near Geneva.
Q How do you find a Higgs boson?
A Protons are spun at almost the speed of light in opposite directions and smashed together. The enormous energy released is converted into new particles.
Like other heavy particles, the Higgs decays into lighter particles, which then decay into even lighter ones. The process can follow a certain number of paths. Physicists compare the decay paths to predicted decay paths. When a match is found, it suggests the observed particle is the one being searched for.
Q. Why has it taken so long to find it?
A. Suggesting something in theory is one thing, but proving its existence can be quite tricky. It seems that Higgs particles, if they do indeed exist, only exist for a fraction of a second. Theory suggests that enough of them should become detectable if beams of protons are collided together at high enough energies. Until the Large Hadron Collider was built a few years ago, previous colliders were not able to reach these energy levels.
Q. So have scientists actually found the Higgs?
A. Not quite, or at least not to the confidence levels they would like to achieve. They have definitely found a new subatomic particle with a mass of about 130 protons and the preliminary results certainly fit in with it being a Higgs boson. It may be the Higgs boson, or it may be one of several – the theory suggests there may be more than one.
Q How did the Higgs boson get the nickname ‘the God particle’?
A Nobel laureate physicist Leon Lederman wrote a book in the early 1990s about the search for the elusive Higgs boson. His publishers coined the name as a marketable title for the book, but it’s disliked by many scientists.
Q. Why does such a discovery matter?
A. Physicists trying to understand the Universe have come up with a theoretical framework that brings together the various forces of nature. It is called the Standard Model. But the problem was that the model did not explain why matter has mass, that is without invoking a Higgs boson. So finding the Higgs is powerful support for the correctness of the Standard Model. If the Higgs was not found, then the entire edifice of modern theoretical physics would fall apart.
Q. Is this the end of particle physics?
A. It’s just the end of the beginning. Confirming the existence of the Higgs would only be the start of a new era of particle physics as scientists focus on understanding how it works and look for unexpected phenomena.
Q. Where do we go from here?
A. Further work will be necessary to confirm the new particle is indeed the Higgs. The Large Hadron Collider meanwhile has many other projects on the go, such as discovering “super symmetry”, the idea that subatomic particles have symmetrical twins.
Q. Did everyone think it would happen?
A. Not everyone. In 2000, Professor Stephen Hawking bet the University of Michigan’s Gordon Kane $100 that the Higgs would never be found. Yesterday he admitted he would have to pay up.