BIG BANG DAY (Large Hadron Collider)
Abhi
On 10th September, 2008, at 12.30 pm IST is the long-awaited day when the Large Hadron Collider (LHC) is switched on at the CERN laboratories in Switzerland. A group of physicists turned on a machine that will recreate the birth of the universe, the Raniwala couple from Jaipur will be watching the experiment very closely. After all, this will be the largest experiment in human history. And Sudhir Raniwala and Rashmi Raniwala, associate professors of physics at Rajasthan University, are among the 30-odd physicists from India, who are part of this experiment.
At the heart of this is the Large Hadron Collider (LHC), which was constructed at a cost of $4.4 billion. It is the latest in a series of successively more powerful particle accelerators that have been built at the European Centre for Nuclear Research (CERN) laboratory in Geneva. At the heart of this is the Large Hadron Collider (LHC), which was constructed at a cost of $4.4 billion. It is the latest in a series of successively more powerful particle accelerators that have been built at the European Centre for Nuclear Research (CERN) laboratory in Geneva. Within the LHC's circular tunnel, 27 km in circumference, beams of protons will be accelerated to up to 99.999999% of the speed of light. When they smash together, they will generate concentrations of energy resembling those that occurred during the first trillionth of a second after the Big Bang.
Big Bang Theory:
The Big Bang is the cosmologicalmodel of the universe that is best supported by all lines of scientific evidence and observation. The essential idea is that the universe has expanded from a primordial hot and dense initial condition at some finite time in the past and continues to expand to this day. Georges Lemaitre proposed what became known as the Big Bang theory of the origin of the Universe, although he called it his 'hypothesis of the primeval atom'. The framework for the model relies on Albert Einstein's General Relativity as formulated by Alexander Friedmann. After Edwin Hubble discovered in 1929 that the distances to far away galaxies were generally proportional to their redshifts, this observation was taken to indicate that all very distant galaxies and clusters have an apparent velocity directly away from our vantage point. The farther away, the higher the apparent velocity. If the distance between galaxy clusters is increasing today, everything must have been closer together in the past. This idea has been considered in detail back in time to extreme densities and temperatures, and large particle accelerators have been built to experiment on and test such conditions, resulting in significant confirmation of the theory. But these accelerators can only probe so far into such high energy regimes. Without any evidence associated with the earliest instant of the expansion, the Big Bang theory cannot and does not provide any explanation for such an initial condition, rather explaining the general evolution of the universe since that instant. The observed abundances of the light elements throughout the cosmos closely match the calculated predictions for the formation of these elements from nuclear processes in the rapidly expanding and cooling first minutes of the universe, as logically and quantitatively detailed according to Big Bang nucleosynthesis.
Fred Hoyle is credited with coining the phrase 'Big Bang' during a 1949 radio broadcast, as a derisive reference to a theory he did not subscribe to. Hoyle later helped considerably in the effort to figure out the nuclear pathway for building certain heavier elements from lighter ones. After the discovery of the cosmic microwave background radiation in 1964, and especially when its collective frequencies sketched out a blackbody curve, most scientists were fairly convinced by the evidence that some Big Bang scenario must have occurred.
What is Large Hadron Collider?
The Large Hadron Collider (LHC) is the world's largest particle accelerator complex, intended to collide opposing beams of 7 TeVprotons. Its main purpose is to explore the validity and limitations of the Standard Model, the current theoretical picture for particle physics. The LHC was built by the European Organization for Nuclear Research (CERN), and lies under the Franco-Swiss border near Geneva, Switzerland. The LHC is the world's largest and the highest-energy particle accelerator. It is funded and built in collaboration with over eight thousand physicists from over eighty-five countries as well as hundreds of universities and laboratories.
The collider is contained in a circular tunnel with a circumference of 27 kilometers (17 mi) at a depth ranging from 50 to 175 metreshadr ons). The two beams travel in opposite directions around the ring. Some 1,232 bending magnets keep the beams on their circular path, while an additional 392 focusing magnets superconducting magnets are installed, with most weighing over 27 tonnes. Approximately 96 tonnes of liquid helium is needed to keep the magnets at the operating temperature (1.9K), making the LHC the largest cryogenic facility in the world at liquid helium temperature. underground. The collider tunnel contains two adjacent beam pipes, each containing a proton beam (a proton is one type of are used to keep the beams focused, in order to maximize the chances of interaction between the particles in the four intersection points, where the two beams will cross. In total, over 1,600 hadrons). The two beams travel in opposite directions around the ring. Some 1,232 bending magnets keep the beams on their circular path, while an additional 392 focusing magnets are used to keep the beams focused, in order to maximize the chances of interaction between the particles in the four intersection points, where the two beams will cross. In total, over 1,600 superconducting magnets are installed, with most weighing over 27 tonnes. Approximately 96 tonnes of liquid helium is needed to keep the magnets at the operating temperature (1.9K), making the LHC the largest cryogenic facility in the world at liquid helium temperature.
Purpose:
When activated, it is theorized that the collider will produce the elusive Higgs boson. The verification of the existence of the Higgs boson would be a significant step in the search for a Grand Unified Theory, which seeks to unify three of the four known fundamental forces: electromagnetism, the strong nuclear forceweak nuclear force leaving out only gravity. The Higgs boson may also help to explain why gravitation is so weak compared with the other three forces. In addition to the Higgs boson, other theorized particles, models and states might be produced, and for some searches are planned, including super symmetric particles, compositeness (Technicolor, extra dimensions, strangelets, micro black holes and magnetic monopoles.
Construction accidents and delays:
On 25 October 2005, a technician was killed in the LHC tunnel when a crane load was accidentally dropped. On 27 March 2007 a cryogenic magnet support broke during a pressure test involving one of the LHC's inner triplet (focusing quadrupole) magnet assemblies, provided by Fermilab and KEK. No one was injured. Fermilab director Pier Oddone stated "In this case we are dumbfounded that we missed some very simple balance of forces". This fault had been present in the original design, and remained during four engineering reviews over the following years.Analysis revealed that its design, made as thin as possible for better insulation, was not strong enough to withstand the forces generated during pressure testing. Details are available in a statement from Fermilab, with which CERN is in agreement.Repairing the broken magnet and reinforcing the eight identical assemblies used by LHC delayed the startup date, then planned for November 2007, by several weeks.
References:
1. Times Of India.
2. BBC News.
3. Wikipedia.
. |
