Shadow of complex fixed point: Approximate conformality of Q>4 Potts model

Understand

We study the famous example of weakly first order phase transitions in the 1+1D quantum Q-state Potts model at Q>4.

• We numerically show that these weakly first order transitions have approximately conformal invariance.
• Specifically, we find entanglement entropy on considerably large system sizes fits perfectly with the universal scaling law of this quantity in the conformal field theories (CFTs).
• This supports that the weakly first order transitions is proximate to complex fixed points, which are described by recent conjectured complex CFTs.