New phase transition in random planar diagrams and RNA-type matching

Autor: Lokhov, Andrey Y., Nechaev, Sergei K., Tamm, Mikhail V., Valba, Olga V.
Rok vydání: 2013
Předmět:
Zdroj: Phys. Rev. E 88, 052117 (2013)
Druh dokumentu: Working Paper
DOI: 10.1103/PhysRevE.88.052117
Popis: We study the planar matching problem, defined by a symmetric random matrix with independent identically distributed entries, taking values 0 and 1. We show that the existence of a perfect planar matching structure is possible only above a certain critical density, $p_{c}$, of allowed contacts (i.e. of '1'). Using a formulation of the problem in terms of Dyck paths and a matrix model of planar contact structures, we provide an analytical estimation for the value of the transition point, $p_{c}$, in the thermodynamic limit. This estimation is close to the critical value, $p_{c} \approx 0.379$, obtained in numerical simulations based on an exact dynamical programming algorithm. We characterize the corresponding critical behavior of the model and discuss the relation of the perfect-imperfect matching transition to the known molten-glass transition in the context of random RNA secondary structure's formation. In particular, we provide strong evidence supporting the conjecture that the molten-glass transition at T=0 occurs at $p_{c}$.
Comment: 8 pages, 6 figures (we have added the new fig.4)
Databáze: arXiv