To unravel the mystery of our existence physicists have devised theories which account for both the large-scale and small-scale structure of the universe. One such theory, called the Standard Model has been the pillar of fundamental physics. It explains the origin of mass in the universe. According to this theory all matter in the universe is built from the tiniest, almost massless, fundamental entities called quarks and leptons. Three quarks bind together to form the proton and neutron. Gluons bring about the binding of quarks.
The neutrons and protons stick together to form nuclei — the tiny, core of atoms. Another kind of particles called leptons appear in nature in two types: electrically charged and neutral (uncharged). Neutral leptons are called neutrinos. There are three known charged leptons named as electron, muon and tau, electron being the lightest of them.
Electrons which are negatively charged, are attracted to nuclei, which are positively charged, to form atoms. Atoms coalesce together to form matter making up everything in the world.
Physicists across the world are experimenting to test this theory. Results from these experiments substantiate many of its predictions. But also show some anomalies. An important anomaly among these is the discovery that even the tiniest particles have definite mass.
The Standard Model, however, assumes that they don’t!
To settle this British Physicist Peter Higgs proposed that there exists a mysterious particle called Higgs Boson, nicknamed the “God particle” by Nobel laureate Leon Lederman that pervades the entire universe and explains how everything is the way it is. It is assumed that Higgs somehow interacts with all other forms of matter to give them their mass i.e. to make them weigh something.
No one knows whether the Higgs particle exists or not. But in the ultimate leap of faith, physicists across the world are preparing to build one of the most ambitious and expensive science experiments to study the mechanism that makes the fundamental mass, one of the essentials of creation of universe and hence our existence.
Experts from Europe, Asia and the US have entered into collaborations to build a gigantic atom smashing machine called Large Hadron Collider (LHC) at the European Center for Research in Nuclear and Particle Physics (CERN) in Geneva, Switzerland. Buried underground in a circular tunnel of 27 km circumference, the collider will collide protons head-on at very high speeds. The resulting catastrophic explosion of heat, light and radiation at energies as high as 14 TeV will recreate the conditions encountered in first few billionths of a second of the creation of universe. Physicists hope and aspire that the Higgs-Boson will then show up.
A huge layered particle detector built using the cutting-edge technology involving both hardware and software is used for tracking and identifying the particles produced in collisions. Computer simulations based on the information from all the layers reconstruct the particle track and identify its momentum, energy, and speed.
On the proton-proton Large Hadron Collider (LHC) at CERN, scientists are building huge detectors to discover Higgs-Boson and to discover signatures of new physics. The Compact Muon Solenoid (CMS) is one of the four detectors being built by approximately 2300 members of a collaboration formed by about 160 institutions, world over, including Tata Institute of Fundamental Research (TIFR) & Bhabha Atomic Research Center (BARC) Mumbai, Delhi University and Department of Physics, Panjab University, Chandigarh.
The cylindrical CMS detector will be 21 metres long and 16 metres in diameter weighing approximately 12300 tons. The Indian groups have been funded jointly by Department of Atomic Energy (DAE) and Department of Science & Technology (DST), Govt. of India to build parts of this detector. Teams of researchers from these institutions are deputed to CERN in Geneva for installing these parts on the
detector
The author is Professor-in-Physics and Fellow, Panjab University
