Hey, math nerds, I really want to know, why is Wikipedia saying that $$\wp(X)$$ is a notation for the power set? First time I see the Weierstrass pe symbol used for something other than an elliptic curve, and I don't like it, my boy Weierstrass didn't write no power sets like that.

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Gimme a damn citation for that notation, Wikipedia.

@JordiGH I've seen Ps with various degrees of swirliness denote powerset, but never the weierstrauss p.

From wikipedia "Talk:Power_set":

"℘ is really only used for the power set by people who don't know how to get a script looking P in LaTeX any other way."

@JordiGH That quote is from 2009, and no citation has been seen since.

@j I have half a mind to just go into Wikipedia and get rid of that silly notation until someone comes along with a citation.

@JordiGH I found two uses on arxiv.

@j Dammit!

Are they published?

@JordiGH Doesn't look like it at least. I think that still validates the wikipedia user who said "℘ is really only used for the power set by people who don't know how to get a script looking P in LaTeX any other way."

@j I feel like a reasonable editor should catch that mistake.

@JordiGH I've seen some people \wp as a powerset symbol in LaTeX (but it's clear from context they don't know the difference with \mathcal{P})

@Vierkantor Hm, really? The Wikipedia talk page agrees that people are doing it because they don't know better. Like using <> for inner products instead of \langle and \rangle?

@JordiGH I tried to figure out where, but it was probably on like an exercise sheet for a Bachelor's course or something like that. Couldn't find any \wp s in the lecture note PDFs I have saved (nor with a quick look through anything on paper).

@Vierkantor I just couldn't take it anymore.

en.wikipedia.org/w/index.php?t

However, I note that the German Wikipedia also says it's a thing:

de.wikipedia.org/wiki/Diskussi

And you seem Dutch, which is close to Germany?

So maybe it's just German notation, the way that tg is Russian notation for the tangent. :)

@JordiGH I can't recall whether it was anyone from Germany using \wp, my gut says no.

Maybe @antonia would like to inform us what's up with powerset symbols in Germany?

@Vierkantor@mastodon.vierkantor.com @JordiGH@mathstodon.xyz I've usually seen $\mathcal P$ in Germany. That other different P might also appear every now and then, but I think I haven't consciously seen it.

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