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the infinite possibilities
in nature are the source of human creativity. out of random processes,
mistakes,
errors - chaotic structures manifest into an order of patterns. the process
of snow crystallization units this themes.
snowflake shapes have
intrigued such scientific luminaries as tene descartes, robert hooke,
johannes
kepler, and antony van leeuwenhoek. the sheer abundance of snowflakes
and their endless variations
on a hexagonal theme supply ample material for study and philosophic contemplation.
snowflakes are
generated when atmospheric water is cooled below its freezing point by
either an invasion of cold air,
or a sudden updraft into cooler elevations. the water doesn't freeze;
it enters a supercooled
(orundercooled) state until it finds a solid substrate upon which it can
condense. snowflake formation
then takes place upon air-borne microscopic dust particles acting as nuclei
for condensation. as in other
chemical reactions, the rapidity of snowflake growth is dependent upon
temperature, pressure, and
concentration of reactants. however, the snowflake's final geometry is
a fractal pattern, and is less
predictable. just as one coastline differs from another by the random
erosion events each has
experienced, so random meteorological events arising during crystallization
yield those limitless
complexities found in snowflake crystals. the effortless appearance of
these natural fractals and their
quiet beauty justify continued scientific appreciation. no two snowflakes
are ever exactly the same
(neither are two lightning bolts). though two such patterns may have the
same overall shape,
if you look
closely you will see that they differ in the details of their structure.
the same is true for other
natural fractals as well. each example is unique, because the chances
are almost zero that exactly the
same sequence of random events will occur in the growth of two different
patterns, such as two
snowflakes.
a mathematical fractal,
by contrast, is constructed according to a set of fixed rules which do
not involve
any random processes. given the fixed rules, the resulting structures
are always identical to one another.
the earliest preserved
illustration of snowflakes is by olaus magnus in 1555. others interested
in snowflakes were descartes (in discours de la methode, 1635) and leuwenhoek
(and there were, and are many more).
it seems that at present there is no accepted explanation why many snowflakes
have a very symmetrical,
hexagonal structure, though the details are quite different for different
flakes. in fact, there is still
research going on in this field. the basic structure comes from the properties
of the water molecules,
no doubt. the problem is that the aggregation process from the supercooled
steam of the cloud is plausibly a local one. hence there is no obvious
reason why it should conserve the symmetry of the growing snowflake.
serious study of
snow crystals was performed in 1910 by a russian meteorologist who identified
246 types
in 176 days of observation. in the 1930s japanese meteorologist ukichiro
nakaya consolidated the list to
seventy-nine categories of crystals plus anomalies and oddballs he called
"mavericksÓ. in 1951 the
international commission on snow and ice simplified things immensely by
devising a classification system
recognizing seven basic forms of snow crystals: plate crystal, stellar
crystal, column, needle, spatial
dendrite, capped column and irregular crystals.
the installation
will display a cold chamber to produce artificial snowflakes, the process
of research will be
part of the installation. besides documentation, like photographs, sketches
and recording experiments,
the exhibition space should be handled as an open room to make the development
for ideas
understandable and alive.
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