Conformal field theories are magical

Understand

"Magic" is the degree to which a state cannot be approximated by Clifford gates.

• We study mana, a measure of magic, in the ground state of the $\mathbb Z_3$ Potts model, and argue that it is a broadly useful diagnostic for many-body physics.
• In particular we find that the $q = 3$ ground state has large mana at the model's critical point, and that this mana resides in the system's correlations.
• We explain the form of the mana by a simple tensor-counting calculation based on a MERA representation of the state.