From Andrew York:

“The Equations of Beauty” is a six-movement suite, and each movement is named for a mathematical constant or variable. The names are h, e, π, i, ∞ and c. These symbols stand for the smallest, the fastest, the infinite, the beautiful and mystical transcendental, irrational and imaginary numbers; all the utmost extremes that inhabit the realm of mathematics. I chose the names to match the spirit of each movement. “Equations” is entirely played with a capo on the fifth fret, and the tuning is D A D F# B D.”

Full story and all recordings at the Guitar Salon International site.