What do the equations on this gate mean or relate to? These equations are on gates to the John Dalton building in Manchester UK: $$X \geq Y \text{ iff } \not\exists \, x_r \leq Y \text{ & } X \leq Y_L $$ $$X = Y \text{ iff } X \leq Y \text{ & } Y \geq X$$ Here’s a picture of the gates !Gates at the John Dalton building Does anybody know what they mean or which work they relate to? I've tagged this mathematical physics, but am not really sure if this is correct.

Looks like Conway's surreal numbers -- check < and his ONAG, and Knuth's introductory book for more information.