Computerized ‘Snowfakes’ Mimic Nature  February 25, 2009
Exquisitely detailed and beautifully symmetrical, the snowflakes
that David Griffeath makes are icy jewels of art.  But don’t be
fooled; there is some serious science behind the University of
Wisconsin-Madison mathematician’s charming creations. Although
they look as if they tumbled straight from the clouds, these
“snowfakes” are actually the product of an elaborate computer
model designed to replicate the wildly complex growth of snow
crystals.  Four years in the making, the model that Griffeath
built with University of California, Davis, mathematician Janko
Gravner can generate all of nature’s snowflake types in rich
three-dimensional detail. In the January issue of Physical
Review E, the pair published the model’s underlying theory and
computations, which are so intensive they are “right on the edge
of feasibility,” says Griffeath.   In nature, each snowflake
begins as a bit of dust, a bacterium or a pollutant in the sky,
around which water molecule