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ggm
I increasingly find the no two alike thing exasperating. Almost nothing in nature above the subatomic/atomic/molecule level is "alike" in crystals or anything else. Making BIPM spheres of counted atoms does not truly make them identical. Cubic crystals of salt will have differences.

At the level of detail most people can discern, I suspect many morphological forms of ice crystal are very alike, and we have to resort to the small imperfections to get to not alike.

Nothing is exactly the same. That's what discrete countable things are: distinct.

(Of course it's semantics. And poetic license. Most snowflakes are trivially unlike, and those which are nearly alike have discernible difference if you go looking for them. As do cells, flowers, grains of sand.. )

topherclay
That's a fun thought experiment: to imagine what level of detail of snowflakes most people are able to discern.

Reminds me of a little bit of that one xkcd.

https://xkcd.com/2501/

zafka
Thanks! Your comment compelled me to look up olivine and then feldspar to check their formulas. Becoming much more aware of the makeup of minerals is on my list of things to do.
behnamoh
Do we have evidence or proof about "no two alike" or is it more like an educated guess?
beenBoutIT
Snowflakes processed via this method could be the future of true random.
j4yav
There's a whole class of factoids where it seems some people are unable to resist bringing it up even when the connection to the current discussion is quite tenuous, and a reactionary set of people who are unable to resist a stock reply to the mention (which varies depending on the topic, but generally it's an "actually" calling out some exception to the first statement). In reality, everyone has read both the factoid and the stock reply a million times.

It would be interesting to document and track these. They are almost like little autonomous programs that run on people's consciousness, which I guess is a just a meme per the original definition.

cwillu
Obligatory xkc… nevermind.
jerzmacow
Another one is measuring with football fields! We can't resist doing it, nor can we resist complaining about it
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OJFord
> device, which stands at about five feet in height off the ground when placed on a table

And is about the length of three football fields when dismantled and spaced equally across them?

BobaFloutist
Good catch, that's a remarkably poor description. A table can easily be anywhere from like two to four feet tall, so this device is anywhere from one to three feet tall, neither of which sounds nearly as impressive as five feet.
hooloovoo_zoo
Hehe snowflakes should prove a patent challenge worthy of Myrvhold.
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hermitcrab
I don't understand how snowflakes are different to each other and yet also symmetric. Are they always symmetric?
tim333
The symmetry is imperfect.
hermitcrab
I don't understand how they are even close to symmetric. The 'seed' seems unlikely to be symmetric. There is no way for one 'arm' to communicate directly with another. And the conditions (temperature etc) is unlikely to be completely uniform around that seed.
neurostimulant
> The ice crystals that make up snowflakes are symmetrical (or patterned) because they reflect the internal order of the crystal’s water molecules as they arrange themselves in predetermined spaces (known as “crystallization”) to form a six-sided snowflake.

https://www.noaa.gov/stories/how-do-snowflakes-form-science-...

hermitcrab
>Because each arm experiences the same atmospheric conditions, the arms look identical.

Thanks. But I'm still not convinced. If it is just that the microclimate around the seed is the same, why aren't adjacent crystals identical?

clintfred
Maybe they are? Has this been tested?
firecall
I was also wondering why they form six arms, for want of a better description?
ekanes
Fun fact - the inventor is none other than Nathan Myhrvold, the OG patent troll.