title: Imaginary fixed points can be physical.
abstract: It has been proposed that a first-order phase transition driven to happen in the metastable region exhibits scaling and universality near an instability point controlled by an instability fixed point of a φ(3) theory. However, this fixed point has an imaginary value and the renormalization-group flow of the φ(3) coupling diverges at a finite scale. Here combining a momentum-space RG analysis and a nucleation theory near the spinodal point, we show that imaginary rather than real values are physical counterintuitively and thus the imaginary fixed point does control the scaling.
authors.affiliation: State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-sen University, Guangzhou 510275, People's Republic of China.
authors.forename: Fan
authors.initials: F
authors.lastname: Zhong