View from the Sidewalk.

While perambulating recently, I was stopped in my tracks by the oddest, most erudite of graffiti.

Strictly speaking, since the message was not written by hand (graph-itti) it might be called a poster or one of those bills nobody wants others to post. Whatever the actual medium, when slapped onto a garage door, the message is both mysterious and unsettling.

A citizen in the 21st Century, I turned immediately to the inter webs. 

I will not deny that my first thought was that it was some sort of political code. And perhaps it is...one that might encourage deescalation. I mean, really: people are CHEERING that an 82-year-old got his head bashed in by a home intruder?

Well anyhoo, the formula I known as Euler's Identity. Which sounds like a spy story, but that name is pronounced "Oiler's". So, less international-operative let us say, and more rogue garage-mechanical. 

And, she re-phrased with laser-like focus, it's commonly considered the most beautiful of mathematical equations.  (I wonder if they have an annual contest with capes and crowns and airbrushed tans).  

​It's been likened to a Shakespearean sonnet, and my favorite starry-eyed quote about the formula is that it "is absolutely paradoxical; we cannot understand it and we don't know what it means, but we have proved it and it must be the truth."  

But wait, she said plaintively, what the Euler's identity DO in the world? Short answer: math stuff that I cannot, for the life of me and the love of light, manage to keep herded up in my brain for long enough to summarize. Dang. We REALLY don't know what it means.

Ah, but wait. Plot thickens: there's Euler's Identity, Euler's Constant, Euler's Four-Square Identity (okay, check this shiznit: double the sum of 4 squared numbers and the result can be expressed as the sum of four squares whaaaaa),  Euler's Number,  Euler's other Number (a cavitation number in fluid dynamics), and Euler's Theory, and, Holy Bologna on a pony –– Euler's Lucky Numbers. Which are, btw, a series of prime numbers that, well, geek.  

​Ooh! electronic music based on it can be seen here.

And of course there's a Euler's Society.

And to think I saw it on Mulberry Street.