Thursday, December 20, 2007

266)2008:The year all the rest of those teensy-weensy, itsy-bitsy particles that make up material reality may be uncovered, courtesy of the LHC.

LHC=Large Hadron Collider

CERN=Europe's Main Particle Physics Laboratory in Geneva, Switzerland.

"Science is a wonderful, powerful tool and research budgets are essential. But Science is only the beginning in the new age we are entering. Islam does not perceive the world as two seperate domains of mind and spirit, science and belief. Science and the search for knowledge are an expression of man's designated role in the universe, but they do not define that role totally....."(Aga Khan IV, McMaster University Convocation, Hamilton, Ontario, Canada, May 15th 1987).

"....The Qur’an itself repeatedly recommends Muslims to become better educated in order better to understand God’s creation"(Closing Address by His Highness Aga Khan IV at the "Musée-Musées" Round Table Louvre Museum, Paris, France, October 17th 2007)

"Inside it, he and the thousands of other physicists who work at CERN hope to find the secrets of the universe: dark matter, dark energy, extra dimensions, tiny black holes that evaporate in an eye-blink and the origins of mass itself":

Particle physics

Merry Christmas, Dr Heuer

Dec 19th 2007
From The Economist print edition

The most prestigious job in physics is about to change hands

NAPOLEON once asked of a newly appointed general, “Has he luck?” Rolf-Dieter Heuer clearly does—and in Napoleonic quantities. At the moment, he is the research director of the German Electron Synchrotron, an important but local institution based in Hamburg. On December 13th, however, he was chosen to be the next director-general of CERN, Europe's main particle-physics laboratory.

Luckier still, he does not actually start his term for 12 months. By then, if all has gone well, he will be in charge of the best Christmas present that a physicist could imagine—the world's biggest particle accelerator. Inside it, he and the thousands of other physicists who work at CERN hope to find the secrets of the universe: dark matter, dark energy, extra dimensions, tiny black holes that evaporate in an eye-blink and the origins of mass itself.

Dr Heuer's unlucky predecessor, Robert Aymar, has sweated out his own five-year term trying to get this behemoth of a machine, which is called the Large Hadron Collider (LHC), finished approximately on time and approximately on budget. Approximately, it looks as though he has succeeded. If all goes well, the LHC's first test run should happen in the summer, only two years late. Meanwhile, the creative financing techniques Dr Aymar employed to accomplish this—borrowing against future income in a way that the heads of pure-science projects rarely dare to do—seem to have worked, and not bankrupted the LHC as some more nervous people feared they might. Unfortunately for Dr Aymar, it is Dr Heuer who will reap the reward, for after a decade and a half in the wilderness since the United States abandoned its own plans for a giant accelerator, called the superconducting super-collider, the subject of particle physics is just about to get sexy again.

Standard deviations

The wilderness from which the field is emerging is called the Standard Model. This description of the way the universe works was built up in the early 1970s. It links together, in a reasonably satisfying mathematical way, all of the known fundamental particles (electrons, quarks, photons and so on) and three of the four known fundamental forces (electromagnetism, and the strong and weak forces that shape atomic nuclei). However, it is not a complete explanation. The force of gravity, for instance, is not yet part of it. Nor has its explanation of the existence of mass yet been proved true. And it relies on a lot of mathematical fiddle factors that are disturbingly arbitrary. Also, it has hardly changed for 35 years, and physicists are getting bored with it.

The LHC exists to relieve that boredom. Though its first task—to find a particle called the Higgs boson—has been talked up endlessly, the Higgs is actually just unfinished business from the Standard Model. The Higgs is the missing element needed for mass to exist. Since mass clearly does exist, an absence of Higgs would be a real shock. But assuming it is there, as everyone expects, the exciting stuff will be what happens afterwards.

That journey beyond the Standard Model is what the LHC was really built for. The machine itself is a pair of ring-shaped pipes, each 27km long, buried 100 metres down in a layer of rock between Geneva and the Jura mountains. The pipes are surrounded by powerful magnets that guide and accelerate the particles within, so that they whizz round in opposite directions at close to the speed of light. This gives them enormous energy and, because energy and mass are two aspects of the same thing, enormous mass as well.

The collisions between these particles that are the purpose of all this engineering take place in four huge particle-detecting machines buried in caverns on the ring's circumference. The pipes—and the streams of protons they are carrying—cross in the middle of each of these machines. When the protons from opposing streams bash into each other, the alchemy of subatomic physics creates new, massive and generally unstable particles—of which the Higgs should be one example. These quickly decay into showers of daughter particles that shoot out through concentric layers of detectors made of materials such as liquid argon and the purest crystals of silicon available. Each layer is designed to measure the passage of a different class of daughter. By analysing the daughters, the nature of the massive parents that gave birth to them can be worked out.

All this happens fast. Very fast. When the LHC is running at full speed, each detector will have to deal with a billion collisions a second. That is way beyond what even the best modern computers can study thoroughly, so most are given a cursory glance and thrown away. The truly promising—a few hundred a second—are stored for future examination.

Unwrapping reality

The first big discovery probably will be the Higgs. But not necessarily. Theory suggests that something called a neutralino would require about the same amount of energy as a Higgs to make, and so it might turn up at about the same time. A neutralino is a very different sort of beast—one that promises to lead physics into the promised land that is called supersymmetry.
Supersymmetry brings hope that physics will be able to jettison the Standard Model's arbitrary fiddle factors. The price it extracts for doing so is to double the number of particles needed to make sense of the universe. Neutralinos are (or, at least, are predicted to be) the lightest and most stable of these new particles. And their stability means they may also solve a cosmological mystery, which is that a quarter of the universe seems to be made of dark matter that can be detected only by its gravitational interactions. Many physicists think this dark matter is made largely of neutralinos.

That neutralinos feel gravity but not electromagnetism makes them hard to detect. (They also feel the weak nuclear force, but that, as its name suggests, is little help.) The way to find a neutralino, therefore, is to note everything else that comes out of a collision and see if any energy is missing. If that missing energy matches the expected energy of a neutralino, then that is probably what has escaped detection.

A similar trick will be used to look for gravitons—hypothetical particles that may carry the force of gravity. These, too, would be an extension to the Standard Model. Moreover, if their missing energies turn out to have a particular set of values, it will be evidence that they live part of their lives in a hitherto undetected fifth dimension (the other four being length, breadth, height and time). That, in turn, will cast light on the complex field of string theory, which is the best available “theory of everything”, even though it requires the existence of not five, but 11 dimensions.

Miniature black holes that evaporate in a hail of particles known as the Hawking radiation may also turn up in the detectors. That would allow Stephen Hawking, who predicted such radiation in 1974, to collect a much-deserved Nobel prize—just as discovering the Higgs would surely grant one to Peter Higgs, who realised the need for such a particle in 1964. (Nobel prizes are not awarded to theoreticians until their theories have been proved.)

Indeed, the Higgs itself may do more than merely create mass. Put a bunch of them together and they will repel one another in a way that takes the very fabric of space along with them. They could thus be the explanation for the sudden inflation that the universe seems to have undergone just after it came into existence. They could even help to explain another 70% of the universe whose nature is unknown—the dark energy that is pushing space apart even now.

With all this to play for, Dr Heuer is a very lucky man indeed. As long as the machine behaves, of course. If it does not—and when you are running something whose operating temperature is just above absolute zero, and which has the power consumption of a small town, you can never be sure—then the SFr6 billion or so (about $5 billion) it has cost will start to look rather pricey. And if that happens, then particle physics may find itself back in the wilderness for good.

These were earlier articles related to the above topic which I placed on my old blog:

Easy Nash aka easynash

Islam, eminently logical, placing the greatest emphasis on knowledge, purports to understand God's creation:Aga Khan 4(2006)
The God of the Quran is the One whose Ayats(Signs) are the Universe in which we live, move and have our being:Aga Khan 3(1952)
Our interpretation of Islam places enormous value on knowledge. Knowledge is the reflection of faith if it is used properly. Seek out that knowledge and use it properly:Aga Khan 4(2005)
All human beings, by their nature, desire to know(Aristotle, The Metaphysics, a few hundred years BC)