2025/10/22 by Martin Hasenbusch, Hasenbusch, Martin · 1 citation
Physics and Astronomy · Mathematics · #Theoretical and Computational Physics #Stochastic processes and statistical mechanics #Quantum Chromodynamics and Particle Interactions
paper · pdf · doi:10.48550/arxiv.2510.19473
We study the 2-component ϕ4 model on the simple cubic lattice in the presence of a cubic, or equivalently, a \mathbbD4 invariant perturbation. To this end, we perform Monte Carlo simulations in conjunction with a finite size scaling analysis of the data. We follow previous work on the 3-component case. We study the RG flow from the decoupled Ising fixed point into the O(2)-invariant one and towards the fluctuation induced first order transition. To this end we study the behavior of phenomenological couplings. At the O(2)-invariant fixed point we obtain the estimate Y4=-0.1118(10) of the RG-exponent of the perturbation. Note that the small modulus of Y4 means that the RG flow is slow. Hence, in order to interpret experiments or Monte Carlo simulations of lattice models, which are effectively described by the ϕ4 model with a cubic term, we have to consider the RG flow beyond the neighborhood of the fixed points.