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Source:  Wikipedia

The Higgs boson is an elementary particle in the Standard Model (SM) of particle physics. It belongs to a class of particles known as bosons, characterized by an integer value of their spin quantum number. The Higgs field is a quantum field that fills all of space. Fundamental particles (or elementary particles) such as quarks and electrons acquire mass through the Higgs mechanism. The Higgs boson is the quantum of the Higgs field, just as the photon is the quantum of the electromagnetic field. The Higgs boson has a large mass, however, which is why a large accelerator is needed to study it.
The existence of the Higgs boson was predicted by the Standard Model to explain how spontaneous breaking of electroweak symmetry (the Higgs mechanism) takes place in nature, which in turn explains why other elementary particles have mass.[Note 1] Its discovery has validated the Standard Model as essentially correct, and was the final elementary particle predicted by the Standard Model to be observed in particle physics experiments.[3] The Standard Model completely fixes the properties of the Higgs boson, except for its mass. It is expected to have no spin and no electric or color charge, and it interacts with other particles through the weak interaction and Yukawa-type interactions between the various fermions and the Higgs field. Alternative sources of the Higgs mechanism that do not need the Higgs boson are also possible and would be considered if the existence of the Higgs boson were ruled out. They are known as Higgsless models.
Experiments to determine whether the Higgs boson exists are currently being performed using the Large Hadron Collider (LHC) at CERN, and were performed at Fermilab's Tevatron until its closure in late 2011. Mathematical consistency of the Standard Model requires that any mechanism capable of generating the masses of elementary particles become visible at energies above 1.4 TeV;[4] therefore, the LHC (designed to collide two 7-TeV proton beams) is expected to be able to answer the question of whether or not the Higgs boson actually exists.[5] In December 2011, Fabiola Gianotti and Guido Tonelli, who were then spokespersons of the two main experiments at the LHC (ATLAS and CMS) both reported independently that their data hints at a possibility the Higgs may exist with a mass around 125 GeV/c2 (about 133 proton masses, on the order of 10−25 kg). They also reported that the original range under investigation has been narrowed down considerably and that a mass outside approximately 115–130 GeV/c2 is almost ruled out.[6] It was anticipated that the LHC would provide sufficient data by the end of 2012 for a definite answer.[2][7][8][9]
Around 28 June 2012 rumors began to spread in the media that an announcement was anticipated, but it was unclear whether this would be a stronger signal, or a formal discovery.[10] On 4 July 2012, Fabiola Gianotti and Joseph Incandela, current spokespersons for the ATLAS and CMS experiments, and chief executive of the Science and technology Facilities Council John Womersley, presented the latest results on the Higgs from the LHC.[11] They confirmed the "five sigma" level of evidence needed to show a formal discovery of a particle which was "consistent with the Higgs boson", acknowledging that further work would be needed to conclude that it indeed had all theoretically predicted properties of the Higgs boson.[12][13]
 

The six authors of the 1964 PRL papers, who received the 2010 J. J. Sakurai Prize for their work. From left to right: Kibble, Guralnik, Hagen, Englert, Brout. Right: Higgs.
See also: 1964 PRL symmetry breaking papers and Higgs mechanism
Particle physicists believe matter to be made from fundamental particles whose interactions are mediated by exchange particles known as force carriers. At the start of the 1960s a number of these particles had been discovered or proposed, along with theories suggesting how they relate to each other. However these theories were known to be incomplete. One omission was that they could not explain the origins of mass as a property of matter. Goldstone's theorem, relating to continuous symmetries within some theories, also appeared to rule out many obvious solutions. [14]
The Higgs mechanism is a process by which vector bosons can get rest mass without explicitly breaking gauge invariance. The proposal for such a spontaneous symmetry breaking mechanism was originally suggested in 1962 by Philip Warren Anderson[15] and developed into a full relativistic model in 1964 independently and almost simultaneously by three groups of physicists: by François Englert and Robert Brout;[16] by Peter Higgs;[17] and by Gerald Guralnik, C. R. Hagen, and Tom Kibble (GHK).[18] Properties of the model were further considered by Guralnik in 1965[19] and by Higgs in 1966.[20] The papers showed that when a gauge theory is combined with an additional field which spontaneously breaks the symmetry group, the gauge bosons can consistently acquire a finite mass. In 1967, Steven Weinberg and Abdus Salam were the first to apply the Higgs mechanism to the breaking of the electroweak symmetry, and showed how a Higgs mechanism could be incorporated into Sheldon Glashow's electroweak theory,[21][22][23] in what became the Standard Model of particle physics.
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2010 Sakurai Prize awarded for 1964 Higgs Boson theory work
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The three papers written in 1964 were each recognized as milestone papers during Physical Review Letters's 50th anniversary celebration.[24] Their six authors were also awarded the 2010 J. J. Sakurai Prize for Theoretical Particle Physics for this work.[25] (A dispute also arose the same year; in the event of a Nobel Prize up to 3 scientists would be eligible, with 6 authors credited for the papers.[26] ) Two of the three PRL papers (by Higgs and by GHK) contained equations for the hypothetical field that would eventually become known as the Higgs field and its hypothetical quantum, the Higgs boson. Higgs' subsequent 1966 paper showed the decay mechanism of the boson; only a massive boson can decay and the decays can prove the mechanism.
In the paper by Higgs the boson is massive, and in a closing sentence Higgs writes that "an essential feature" of the theory "is the prediction of incomplete multiplets of scalar and vector bosons". In the paper by GHK the boson is massless and decoupled from the massive states. In reviews dated 2009 and 2011, Guralnik states that in the GHK model the boson is massless only in a lowest-order approximation, but it is not subject to any constraint and acquires mass at higher orders, and adds that the GHK paper was the only one to show that there are no massless Nambu-Goldstone bosons in the model and to give a complete analysis of the general Higgs mechanism.[27][28]
In addition to explaining how mass is acquired by vector bosons, the Higgs mechanism also predicts the ratio between the W boson and Z boson masses as well as their couplings with each other and with the Standard Model quarks and leptons. Many of these predictions have subsequently been verified by precise measurements performed at the LEP and the SLC colliders, thus overwhelmingly confirming that some kind of Higgs mechanism does take place in nature,[29] but the exact manner by which it happens is not yet proven. The results of searching for the Higgs boson are expected to provide evidence about how this is realized in nature.
 The Higgs boson is often referred to as "the God particle" by the media,[73] after the title of Leon Lederman's popular science book on particle physics, The God Particle: If the Universe Is the Answer, What Is the Question?[74][75] While use of this term may have contributed to increased media interest,[75] many scientists dislike it, since it overstates the particle's importance, not least since its discovery would still leave unanswered questions about the unification of Quantum chromodynamics, the electroweak interaction, and gravity, as well as the ultimate origin of the universe.[73] [76]
Lederman said he gave it the nickname "The God Particle" because the particle is "so central to the state of physics today, so crucial to our understanding of the structure of matter, yet so elusive,"[73][74][77] but jokingly added that a second reason was because "the publisher wouldn't let us call it the Goddamn Particle, though that might be a more appropriate title, given its villainous nature and the expense it is causing."[74]
A renaming competition conducted by the science correspondent for the British Guardian newspaper chose the name "the champagne bottle boson" as the best from among their submissions: "The bottom of a champagne bottle is in the shape of the Higgs potential and is often used as an illustration in physics lectures. So it's not an embarrassingly grandiose name, it is memorable, and [it] has some physics connection too."[78]