From Wired Science:
Just a year after the world's fastest supercomputers broke the petaflop barrier by performing one thousand trillion calculations per second, nuclear physicists are planning a 20-petaflop machine in conjunction with IBM.
Nicknamed Sequoia, the Department of Energy computer will most likely be the most powerful in the world when it is released. If it were running today, it'd be more than 10 times faster than any machine in existence.
When it's installed at Lawrence Livermore National Laboratory in 2012, it could make new kinds of calculations possible, but initially, that power will be primarily used to simulate nuclear explosions, as many of its supercomputer forebears have done.
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