On American Independence Day, July 4, physicists working in Geneva at CERN, the world’s biggest particle-physics laboratory, announced that they had found the Higgs boson. Like the uncovering of DNA’s structure by Francis Crick and James Watson in 1953, the discovery of the Higgs makes sense of what would otherwise be incomprehensible. Its significance is massive. Literally. Without the Higgs there would be no mass. And without mass, there would be no stars, no planets and no atoms. And certainly no human beings. Indeed, there would be no history. Massless particles are doomed by Einstein’s theory of relativity to travel at the speed of light. That means, for them, that the past, the present and the future are the same thing.
BOSON was named after an Indian Scientist !!!
The 'boson' in the Higgsboson particle, whose search and ultimate detection was one of the longest and most expensive in the history of science, owes its name to Satyendra Nath Bose who was an Indian Scientist. In 1924, the city-based physicist had sent a paper to Albert Einstein, describing a statistical model that led to the discovery of the Bose-Einstein condensate phenomenon. The paper laid the basis for describing the two classes of subatomic particles - bosons, named after Bose, and fermions, after Italian physicist Enrico Fermi.
Info on Satyendra Nath Bose
Info on Bose-Einstein condensate
Finding the Higgs, though, made looking for needles in haystacks seem simple. The discovery eventually came about using the Large Hadron Collider (LHC), a machine at CERN that sends bunches of protons round a ring 27km in circumference, in opposite directions, at close to the speed of light, so that they collide head on. The faster the protons are moving, the more energy they have. When they collide, this energy is converted into other particles (Einstein’s E=mc2), which then decay into yet more particles. What these decay particles are depends on what was created in the original collision, but unfortunately there is no unique pattern that shouts “Higgs!” The search, therefore, has been for small deviations from what would be seen if there were no Higgs. That is one reason it took so long. The LHC, sustained by a consortium that was originally European but is now global, cost about $10 billion to build.
The discovery puts the finishing flourish on the Standard Model, the best explanation to date for how the universe works—except in the domain of gravity, which is governed by the general theory of relativity. The model comprises 17 particles. Of these, 12 are fermions such as quarks (which coalesce into neutrons and protons in atomic nuclei) and electrons (which whizz around those nuclei). They make up matter. A further four particles, known as gauge bosons, transmit forces and so allow fermions to interact: photons convey electromagnetism, which holds electrons in orbit around atoms; gluons link quarks into protons and neutrons via the strong nuclear force; W and Z bosons carry the weak nuclear force, which is responsible for certain types of radioactive decay. And then there is the Higgs.
The Higgs, though a boson (meaning it has a particular sort of value of a quantum-mechanical property known as spin), is not a gauge boson. Physicists need it not to transmit a force but to give mass to other particles. Two of the 16 others, the photon and the gluon, are massless. But without the Higgs, or something like it, there is no explanation of where the mass of the other particles comes from.
For fermions this is no big deal. The Standard Model’s rules would let mass be ascribed to them without further explanation. But the same trick does not work with bosons. In the absence of a Higgs, the rules of the Standard Model demand that bosons be massless. The W and Z are not. They are very heavy indeed, weighing almost as much as 100 protons. This makes the Higgs the keystone of the Standard Model. Slot it in and the structure stands. Take it out and it topples. Little wonder that physicists were getting impatient.
How is Higgs particle created ? (Click to view larger image)
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