Giacomo Marmorini

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We show that local and semilocal strings in Abelian and non-Abelian gauge theories with critical couplings always reconnect classically in collision, by using moduli space approximation. The moduli matrix formalism explicitly identifies a well-defined set of the vortex moduli parameters. Our analysis of generic geodesic motion in terms of those shows(More)
Many complex networks from the World Wide Web to biological networks grow taking into account the heterogeneous features of the nodes. The feature of a node might be a discrete quantity such as a classification of a URL document such as personal page, thematic website, news, blog, search engine, social network, etc., or the classification of a gene in a(More)
We discuss some aspects of confinement and dynamical symmetry breaking in the so-called nonabelian Argyres-Douglas vacua, which occur very generally in supersymmetric theories. These systems are characterized by strongly-coupled nonabelian monopoles and dyons; confinement and dynamical symmetry breaking are caused by the condensation of monopole composites,(More)
The triangular lattice of S=1/2 spins with XXZ anisotropy is a ubiquitous model for various frustrated systems in different contexts. We determine the quantum phase diagram of the model in the plane of the anisotropy parameter and the magnetic field by means of a large-size cluster mean-field method with a scaling scheme. We find that quantum fluctuations(More)
Magnetization processes of spin-1/2 layered triangular-lattice antiferromagnets (TLAFs) under a magnetic field H are studied by means of a numerical cluster mean-field method with a scaling scheme. We find that small antiferromagnetic couplings between the layers give rise to several types of extra quantum phase transitions among different high-field(More)
We study a class of N = 1 supersymmetric U(N) gauge theories and find that there exist vacua in which the low-energy magnetic effective gauge group contains multiple nonabelian factors, ∏ i SU(ri), supported by light monopoles carrying the assiciated nonabelian charges. These nontrivially generalize the physics of the so-called r-vacua found in softly(More)
One of the main necessities for population geneticists is the availability of statistical tools that enable to accept or reject the neutral Wright-Fisher model with high power. A number of statistical tests have been developed to detect specific deviations from the null frequency spectrum in different directions (i.e., Tajima’s D, Fu and Li’s F and D test,(More)
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