Conformal maps are used by mathematicians, cartographers and
physicists to deform regions in a way that preserves shape on a
small scale. Difficult problems in heat and fluid flow can be
transformed by a conformal map into simple problems whose answers
are already known—in effect, tailoring the solution to fit the
problem. New methods using circle packing are ideally suited for
programming on a computer, and they are being applied to the
challenge of making a conformal map of the human
brain—important for interpreting functional information from
brain imaging.