Faster Computers Accelerate Pace of Discovery
Monday, December 3, 2007
Sometime next year, developers will boot up the next generation of supercomputers, machines whose vast increases in processing power will accelerate the transformation of the scientific method, experts say.
The first "petascale" supercomputer will be capable of 1,000 trillion calculations per second. That's about twice as powerful as today's dominant model, a basketball-court-size beast known as BlueGene/L at the Energy Department's Lawrence Livermore National Laboratory in California that performs a peak of 596 trillion calculations per second.
The computing muscle of the new petascale machines will be akin to that of more than 100,000 desktop computers combined, experts say. A computation that would take a lifetime for a home PC and that can be completed in about five hours on today's supercomputers will be doable in as little as two hours.
"The difficulty in building the machines is tremendous, and the amount of power these machines require is pretty mind-boggling," said Mark Seager, assistant department head for advanced computing technology at Lawrence Livermore. "But the scientific results that we can get out of them are also mind-boggling and worth every penny and every megawatt it takes to build them."
A leading candidate to become the first petascale machine, the "Roadrunner" supercomputer being developed by IBM in partnership with the Energy Department's Los Alamos National Laboratory, will require about 4 megawatts of power -- enough to illuminate 10,000 light bulbs, said John Hopson, program director for advanced simulation and computing at Los Alamos in New Mexico.
But scientists say Roadrunner and its cousins will make possible dramatically improved computer simulations. That will help shed new light on subjects such as climate change, geology, new drug development, dark matter and other secrets of the universe, as well as other fields in which direct experimental observation is time-consuming, costly, dangerous or impossible.
In fact, supercomputers and their simulations are becoming so powerful that they essentially have introduced a new step in the time-honored scientific method that moves from theory to hypothesis to experimental confirmation, some experts contend.
"They are a tool that really helps stimulate the imagination of scientists and engineers in ways that previously weren't possible," said David Turek, vice president of supercomputing at IBM. "You had theory and hypothesis and experimentation. Well, now scientists are admitting that computation is an important part of this, as well."
"Nature is the final arbiter of truth," said Seager, the Lawrence Livermore computer scientist, but "rather than doing experiments, a lot of times now we're actually simulating those experiments and getting the data that way.
"We can now do as much scientific discovery with computational science as we could do before with observational science or theoretical science."
A particularly fruitful area of computer modeling has been the study of global climate change. Ten years ago, experts agreed that humans probably were contributing to global warming. Now, in part because of a 10,000-fold increase computing power and better accuracy in climate simulations, scientists are sure of it.
One result is that computer climate models can now simulate atmospheric and oceanic conditions and, crucially, how changes in each affect the other, experts said. Now the worry is not that computing power is inadequate but that the aging of NASA's weather satellites will lead to a shortage of input data before long, Seager and others said.