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L. Donetti

Publications and source records attributed to L. Donetti.

4 recordsLinked to original sources

Improved spectral algorithm for the detection of network communities

We review and improve a recently introduced method for the detection of communities in complex networks. This method combines spectral properties of some matrices encoding the network topology, with well known hierarchical clustering techniques, and the use of the modularity parameter to quantify the goodness of any possible community subdivision. This provides one of the best available methods for the detection of community structures in complex systems.

physics.soc-ph

The spectral dimension of random trees

We present a simple yet rigorous approach to the determination of the spectral dimension of random trees, based on the study of the massless limit of the Gaussian model on such trees. As a byproduct, we obtain evidence in favor of a new scaling hypothesis for the Gaussian model on generic bounded graphs and in favor of a previously conjectured exact relation between spectral and connectivity dimensions on more general tree-like structures.

cond-mat

Recurrence on the average on trees

In this paper we show that all infinite trees which have bounded coordination and whose surface is negligible with respect to the volume in the limit of large distances (so that they can be embedded in a finite-dimensional euclidean space) are recurrent on the average; this has important consequences about the spontaneous symmetry breaking of statistical models defined on such trees.

cond-mat

Lee-Yang zeros and the Ising model on the Sierpinski Gasket

We study the distribution of the complex temperature zeros for the partition function of the Ising model on a Sierpinski gasket using an exact recursive relation. Although the zeros arrange on a curve pinching the real axis at T=0 in the thermodynamic limit, their density vanishes asymptotically along the curve approaching the origin. This phenomenon explains the coincidence of the low temperature regime on the Sierpinski gasket and on the linear chain.

cond-mat