Nature of the glassy phase of RNA secondary structure

Laboratoire de Physique Théorique et Modèles Statistiques Université Paris-Sud - Bâtiment 100, F-91405 Orsay, France

Received: 29 August 2001
Accepted: 6 December 2001

Abstract

We characterize the low-temperature phase of a simple model for RNA secondary structures by determining the typical energy scale E(l) of excitations involving l bases. At low enough temperatures, including T=0, we find a scaling law with a small exponent θ. Above a critical temperature, there is a different phase characterized by a relatively flat free-energy landscape resembling that of a homopolymer with a scaling exponent . These results strengthen the evidence in favour of the existence of a glass phase at low temperatures.