Martin Zirnbauer - Institute for Theoretical Physics Cologne
Wednesday, February 25, 2026
Zoom opens: 10:30AM EST
Seminar begins: 10:45AM EST
Is conformal symmetry violated at Anderson transitions?
Conformal symmetry has been established as a powerful principle constraining critical phenomena at second-order phase transitions. The so-called conformal "bootstrap" program in particular has resulted in very precise determinations of critical scaling exponents, e.g. for the 3D Ising model. It is therefore noteworthy that the principle of conformal symmetry was recently called into question for the case of disorder-driven Anderson metal-insulator transitions: by a combination of analytical reasoning and numerical simulations detecting a failure of parabolicity of the multifractality spectrum for critical wavefunction moments, it was concluded that conformal symmetry does not apply to Anderson transitions.
In this talk, after reviewing the history of the subject and pointing out a mistake in the field-theoretical analysis, we draw a different conclusion. New large-scale numerical simulations for the network model of the integer quantum Hall transition are, in fact, in excellent agreement with the predictions from conformal field theory (joint work with Abbas Saberi and Sen Mu).