The Ry Gate

The Ry(theta) gate rotates with real amplitudes - the best-behaved trainable gate, and Kronos's default for encoding data and parameters in fusion circuits.

What it does

Ry(theta) acts as the real rotation [[cos(theta/2),-sin(theta/2)],[sin(theta/2),cos(theta/2)]], sweeping smoothly from |0> to |1>.

Where it appears at Kronos

Because real amplitudes give well-behaved gradients, Ry layers are the trainable rotations in Kronos's quantum-machine-learning surrogates and QAOA-style design circuits.

Honest note

These are research tools now; a decisive edge on fusion problems is expected ~mid-2030s.