Griffiths singularities and algebraic order in the exact solution of an Ising model on a fractal modular network

dc.creatorHinczewski, Michael
dc.date2007-01-15
dc.date2007-04-12
dc.date.accessioned2026-07-07T08:05:44Z
dc.date.available2026-07-07T08:05:44Z
dc.descriptionWe use an exact renormalization-group transformation to study the Ising model on a complex network composed of tightly-knit communities nested hierarchically with the fractal scaling recently discovered in a variety of real-world networks. Varying the ratio K/J of of inter- to intra-community coupling, we obtain an unusual phase diagram: at high temperatures or small K/J we have a disordered phase with a Griffiths singularity in the free energy, due to the presence of rare large clusters, which we analyze through the Yang-Lee zeros in the complex magnetic field plane. As the temperature is lowered, true long-range order is not seen, but there is a transition to algebraic order, where pair correlations have power-law decay with distance, reminiscent of the XY model. The transition is infinite-order at small K/J, and becomes second-order above a threshold value (K/J)_m. The existence of such slowly decaying correlations is unexpected in a fat-tailed scale-free network, where correlations longer than nearest-neighbor are typically suppressed.
dc.description7 pages, 4 figures; replaced with final version to appear in Phys. Rev. E
dc.identifierhttps://arxiv.org/abs/cond-mat/0701349
dc.identifierhttp://arxiv.org/abs/cond-mat/0701349
dc.identifierPhys. Rev. E 75, 061104 (2007)
dc.identifierdoi:10.1103/PhysRevE.75.061104
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/130371
dc.subjectDisordered Systems and Neural Networks
dc.titleGriffiths singularities and algebraic order in the exact solution of an Ising model on a fractal modular network
dc.typetext

Files

Collections