Improve this question. Add a comment. Active Oldest Votes. But what about a snowflake? Improve this answer. Brian Webster 1 1 silver badge 8 8 bronze badges. See meta. I thought I'd let you know so you could omit the "Dear In this program a particle diffused around in a box, and clinged to a "seed" in the center.
Result of that were forms very similar to snowflakes. Mark Eichenlaub Gordon Gordon 4, 1 1 gold badge 27 27 silver badges 35 35 bronze badges. AbstractDissonance AbstractDissonance 1. If not, the object should'nt be called a crystal. The less beautiful snow crystals look like columns or needles, but even those have some symmetry.
Leos Ondra Leos Ondra 1, 19 19 silver badges 29 29 bronze badges. Daniel Matthews Daniel Matthews 1. Roald Schrack Roald Schrack 1. Do you think you could include some more details here? Thanks, and welcome to PSE! Please read the introductory paper referenced above. The intricate shape of a single arm of the snowflake is determined by the atmospheric conditions experienced by entire ice crystal as it falls. A crystal might begin to grow arms in one manner, and then minutes or even seconds later, slight changes in the surrounding temperature or humidity causes the crystal to grow in another way.
Although the six-sided shape is always maintained, the ice crystal and its six arms may branch off in new directions. Except for the featureless hexagons, of course. Not only are snowflakes six-sided: they have—to a very good approximation, ignoring damaged or partially melted ones, and so on—sixfold symmetry. The combination of order symmetry and chaos irregular patterns of great diversity seems difficult to explain.
Are snowflakes made by a regular process, or a random one? It seems to be both. And so it is. Johannes Kepler, famous for discovering that planets move in ellipses, was so intrigued by snowflakes that in he wrote a book about them: The Six-Cornered Snowflake.
By pure thought, he was led to the suggestion that the hexagonal character of snowflakes arises because, on some microscopic level, they are made by packing lots of very tiny identical units together. Six identical coins fit exactly around a seventh to form a hexagon. Hexagons pack together like the cells in a honeycomb. Ice, said Kepler, is made from tiny hexagonal patterns, and snowflakes are crystals of ice.
What makes this idea all the more amazing is that in those days the atomic theory of matter was no more than obscure speculation by a few ancient Greek philosophers. We now know that Kepler was right.
The higher the symmetry, the more stable the crystal is. Water molecules floating freely in a vapor begin to arrange themselves into a crystalline solid when the temperature drops below freezing. The two hydrogen atoms of the molecules tend to attract neighboring water molecules.
When the temperature thermal motion is low enough, the molecules link together to form a solid, open framework that has a strict hexagonal symmetry. But why are snowflake shapes so elaborate? Nobody has a good answer for that. The general explanation is that snowflakes form in the atmosphere where conditions are very complex and variable. A crystal might begin to grow in one manner and then minutes or even seconds later something changes temperature or humidity , so it starts to grow in another manner.
The hexagonal symmetry is maintained, but the ice crystal may branch off in new directions. The changes in environmental conditions take place over a large area compared with the size of a single snowflake, so all regions of the flake are similarly affected.
In the end, there are all kinds of forms that can arise: everything from prisms and needles to the familiar lacy snowflakes.
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