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Two Snowflakes May Be Alike After All
An anonymous reader writes "LiveScience is reporting that it may be possible for two snowflakes to be alike after all. For anyone who studies probability, this seems reasonable, given that the article mentions that 10^24 snowflakes fall in any given year. The article contains links to fascinating snowflake pictures. From the article: 'A typical snow crystal weighs roughly one millionth of a gram. This means a cubic foot of snow can contain roughly one billion crystals ... "It is probably safe to say that the possible number of snow crystal shapes exceeds the estimated number of atoms in the known universe," Nelson said. Still, while "no two snowflakes are alike" might hold true for larger snowflakes, Nelson figures it might ring false for smaller crystals that sometimes fall before they have a chance to fully develop. "How likely is it that two snowflakes are alike? Very likely if we define alike to mean that we would have trouble distinguishing them under a microscope and if we include the crystals that hardly develop beyond the prism stage--that is, the smallest snow crystals," Nelson said.'"
I am special. And I'm going to be famous.
...and of course, I can't find it... a scientist published a picture of two identical snowflakes in, I'm almost sure, Science or Nature. And, no, I'm not talking about Snowflake Bentley. It was a byproduct of some kind of meteorological research, they were flying a plane through clouds where snow was being formed, and, as you'd expect, if two flakes of snow form under virtually identical conditions you end up with two virtually identical flakes.
I think this was in the 1990s.
It made the mainstream news at the time.
"How to Do Nothing," kids activities, back in print!
I've always wondered what physicists were doing when they were busy not discovering cold fusion. Seriously though, what I got from this was that while still incredibly unlikely it is possible for two snowflakes to be the same. Just like everything else that is extremely unlikely but not quite impossible.
Am I the only person to think this guy has too much time on his hands?
What goes up must come down. (suspected true)
Lightning doesn't strike the same spot twice. (obviously false (ouch!))
A watched pot never boils. etc...
This is like numerology. You take a bunch of squishy data (aphorisms) and attempt to rigorously evaluate them.
I am reminded of Charlie Brown's answer to the question "How many angels can dance on the head of a pin?" His answer: Eight if they're skinny, four if they're fat.
Don't trust anyone under thirty.
Myth Busted?
A typical snow crystal weighs roughly one millionth of a grama cubic foot of snow can contain roughly one billion crystals...
Most snowflakes are less than one-half inch across. The smallest may be only about one-tenth of a millimeter across...
I think, if you're talking about the myth that Americans do science in metric, then yes: Myth Busted.
When our name is on the back of your car, we're behind you all the way!
-- Neil Gaiman and Terry Pratchett, Good Omens
Some bring out the best in others, some the worst. Some bring out far more.
In other news--it is very likely that two people will have identical fingerprints. If by fingerprints we mean the part of the fingerprint that cannot even be distinguished as a whorl. That is, a couple of cells constituting a tiny fold of skin.
Si la vida me da palo, yo la voy a soportar Si la vida me da palo, yo la voy a espabilar
If someone tells you "You're one in a million," there are 6,571 people exactly like you.
Nancy Knight, 1988
3 95.htm
"The old saw that no two snow crystals are identical was disproved in 1988, when National Center for Atmospheric Research scientist Nancy Knight found two that apparently were. The twin crystals were found by accident when Knight was examining samples collected at 6 kilometers (20,000 feet) over Wisconsin for a cloud-climatology study. Thick, hollow, and columnar, the crystals seem to have been Siamese twins that grew attached to each other. No satisfying explanation has yet been found." -
http://www.proquestk12.com/curr/snow/snow395/snow
proving that a watched pot does indeed boil
Hoorah for science!
1 voice in a sea of voices
This isn't news. No truism is 100% true.
including that one?
my pet machine
So how does the number of possible snowflake configurations compare with the number of possible IPV6 addresses? Can we assign a unique address to every snowflake and then just see if we get an address conflict somewhere?
However, is our starting number of 15 reasonable? The standard snowflake crystals are all formed at temperatures just below freezing under fairly normal conditions. The rate at which the water cools will have a major impact, as will any airborne particles around which the snow crystals can condense. (Particles may cause a break in the symmetry or may force the ice to contain patterns that simply aren't possible when only hexagonal ice crystals are present.) There again, anything dissolved in the water will change the chemistry as well. As not everything freezes at the same temperature, it is entirely possible for snowflakes to acquire bubbles and other oddities where something has remained liquid even as the water froze.
Then, there are the exotic states of frozen H2O which are not considered "ice", per se. Water that has frozen under really strange pressures or at extreme rates will not form regular ice crystals, but form other solid states instead. Slashdot has covered a few of these in the past. Is it possible to have a snowflake form from such states? Maybe. Then you add a whole new set of possibilities to the mix, although it would be unlikely that you could get a mixture of regular ice and these exotic states. (Not impossible, though. If the higher-level clouds chucked down snow in the exotic states, which then got added to by regular snowflake crystals, then you could indeed have a mixture. Not sure this could happen on Earth, but there may be planets where this is common.)
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
So collisions in snowflake based hashing algorithms would be instances of a SnowCrash?
Stop intellectual property from infringing on me
how many lego combinations are possible
To simplify the question, we could consider just these classic bricks. By different combinations we'll understand fully connected arrangements, with no regard to combinations of colour, rotations, or symmetries. I suppose that Legos can connect with a single corner, correct me if I am wrong.
Le(1) = 1
Le(2) = 17
Then, for one of the combinations in Le(2), there are 18 ways to add the third piece. The problem seems to be barely tractable now without the aid of at least lego pieces and a piece of paper, but I'll make bold assumptions. If Le(n) grows at least as fast as 10^n (and my gut tells me that it grows much faster), then measly 100 pieces will give you a quantity that dwarfs the number of particles in the known universe.
The problem is that once you've done a ping sweep of the IPv6 network, the first lot of snowflakes have melted (along with the DHCP server).
Moderation Total: -1 Troll, +3 Goat
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[/sarcasm]
Leave the snowflakes alone, try to research if we can get something to fuel our cars after a decade or two or try to find the cure for utter stupidity. Hearing something useful coming out from science is rather rare these days, probably because really interesting stuff is not published or wouldn't interest the business giants like oil producers.
. .
Believe it or not the largest payout from research is generally not directly the target of the research. We call this serendipity
Off the top of my head the study of this subject would require the researcher to apply his efforts (described here as apparently useless) on the details of crystal formation, manipulating factors of said formation, crystalline structure, and the statistical analysis of crystal formation, besides who knows how many other details that we will never know because we weren't involved.
Let me see if I can come up with some "useless" applications for knowledge in this research track. How about crystalline formation in metals? I bet the aerospace industry has no need for this type of knowledge as they try to come up with ways to grow single crystal blocks of titanium to form turbine blades or anything else that requires insanely high strength. As an example (from memory): the tensile strength of cast iron is a little more then 10,000 psi. The tensile strength of iron formed as a single crystal is somewhere around 100,000 psi! If I remember correctly, the single crystal tensile strength of carbon is 500,000 psi. The reason for these amazing numbers is that the primary weakness is always the crystalline boundaries. (reference: http://en.wikipedia.org/wiki/Single_crystal )
Another "useless" application of this type of research is crystalline formation as it relates to pharmaceutical research. Did you know that the (apparently unimportant and profitless) pharmaceutical companies actually sent an experiment up into orbit just so they could see how crystals grow in zero G? That sounds like it must be an incredibly lavish waste of their shareholder's money (by one of the greediest industries in the world (personal opinion)).
Fun facts:
- When you analyze a crystal you can tell the strength of the gravity field it was formed under.
- Crystalline formation is a state change and controlling this can allow you to do all sorts of interesting things from scalding the hell out of yourself heating water in a microwave, to creating so called meta materials.(reference: http://en.wikipedia.org/wiki/Meta_materials )
- And finally: Utter stupidity is often caused by not looking any deeper then the surface of a subject. (reference: http://www.suck.com/daily/97/11/12/1.html )