Field-rotation equivalence of decoupled Ising theories
= Field-rotation equivalence of decoupled Ising theories
The <orthogonal transformation> $\psi_\pm=(\phi_1\pm\phi_2)/\sqrt2$ takes $g(\phi_1^4+\phi_2^4+6\phi_1^2\phi_2^2)$ to $2g(\psi_+^4+\psi_-^4)$. These are the same two decoupled <Ising models> expressed in rotated fields.