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Vitalik Buterin
@vitalik.eth
Expired: e ^ (i * π) = -1 Tired: e ^ (i * τ) = 1 Inspired: i ^ i is a real number (!!)
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Cryptoflop
@cryptoflop
how come?
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Vitalik Buterin
@vitalik.eth
Think of "a^b" as "start at 1. Take the process that 'grows' the number slowly until it reaches a, and repeat it b times" Think of "i times" as "once, but the process is rotated 90 degrees" (assume we're working on the complex plane)
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Vitalik Buterin
@vitalik.eth
i is as far from the origin as 1 on the complex plane, so "growing from 1 toward i" is really rotation. To get to -1, you need to rotate a half circle, hence e^(i*pi) = -1. And a full circle (tau) gets you back to 1.
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Vitalik Buterin pfp
Vitalik Buterin
@vitalik.eth
For i^i, we take the process of rotating from 1 to i, and rotate *that* 90 degrees. And that means the growth process is instead... going straight toward zero! How far toward zero? The (canonical) value of i^i is equivalent to e^(-pi/2) ≈ 0.208
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