What kind of matter do you study?

Everything that we recognise around us is composed of atoms. Atoms contain a tiny nucleus with electrons going around it. The nucleus is made of protons and neutrons. These are in turn made of particles called quarks. No one has ever succeeded in chipping a quark out of a proton or a neutron. There is even a million dollar prize for proving that this cannot be done. Nature's super-glue which binds quarks together is called a gluon. Quarks and gluons are described by a theory called Quantum Chromodynamics (QCD).  [more]

We study matter made directly out of quarks and gluons, something that may be possible at immensely large temperatures and pressures. Such matter is called the quark gluon plasma. All matter in the universe was just such a soup of quarks and gluons 20 microseconds after the birth of the universe. When this matter cooled it congealed into protons and neutrons, and eventually became the kind of matter that we see all around us.  [more]  [more]

 

What is lattice gauge theory?

Particles as small as quarks and electrons are described by a mathematical model called Quantum Field Theory. One of the ways of making this mathematics tractable is to pretend that space-time is a lattice. With this pretension many computations can be performed which are otherwise intractable. After that one makes the lattice finer and finer, until the effects of the lattice are no longer important. Kenneth Wilson's insight was that this process makes sense, much as Newton's calculus does.

This leaves us with the incredibly time consuming problem of actually doing the computation on finer and finer lattices, and checking whether the effects of the lattice are no longer visible. This requires enormous computing power.  [more]

 

Is all this for real?

Certainly. We may not be able to remember what happened 13.7 billion years ago when the universe was born, but we can jolly well go ahead and try to recreate those conditions in the lab. This is what the relativistic heavy-ion collider at Brookhaven National Lab in Long Island, New York (USA) is built to do. [more]

The universe is a pretty cold place now, but the core of a neutron star is a high pressure environment. Some people believe that the pressure is high enough to melt the neutrons and protons and create quark matter in these cores. [more]

 

What is a super-computer?

A super-computer is a computer which is far faster than most other computers. Since computers become faster as soon as you buy one, this makes super-computing a moving target. For example, the super-computer of 1985 is today's PC.

Computing speeds are measured in "flops". This stands for "floating point operations per second", just a fancy way of saying how many arithmetic operations (such as additions or multiplications) a computer can perform in a second. I can do less than 1 flop. The Cray X1 that we have bought can do upto 200 Giga flops (Giga stands for a billion).  [more]