Articolo in rivista

Weitzenböck's torsion, Fermi coordinates, and adapted frames

We study Weitzenböck's torsion and discuss its properties. Specifically, we calculate the measured components of Weitzenböck's torsion tensor for a frame field adapted to static observers in a Fermi normal coordinate system that we establish along the world line of an arbitrary accelerated observer…

Multiple clustering solutions analysis through least-squares consensus algorithms

Clustering is one of the most important unsupervised learning problems and it deals with finding a structure in a collection of unlabeled data; however, different clustering algorithms applied to the same data-set produce different solutions. In many applications the problem of multiple solutions…

The speciality index and the Lifshitz-Khalatnikov Kasner index parametrization

The speciality index function ${\mathcal S}$ for any Petrov type I, II or D spacetime is shown to be a natural function of a single complex scalar quantity $\mu$ (natural modulo permutation symmetries). For the family of Kasner spacetimes, this quantity is a function of the Kasner indices alone…

Translocation Dynamics of High-Internal Phase Double Emulsions in Narrow Channels

We numerically study the translocation dynamics of double emulsion drops with multiple close-packed inner droplets within constrictions. Such liquid architectures, which we refer to as HIPdEs (high-internal phase double emulsions), consist of a ternary fluid, in which monodisperse droplets are…

IMSP schemes for spatially explicit models of cyclic populations and metapopulation dynamics

We examine spatially explicit models described by reaction-diffusion partial differential equations for the study of predator-prey population dynamics. The numerical methods we propose are based on the coupling of a finite difference/element spatial discretization and a suitable partitioned Runge-…

On the Modification of the Cosmic Microwave Background Anisotropy Spectrum from Canonical Quantum Gravity

We evaluate the modifications to the cosmic microwave background anisotropy spectrum that result from a semiclassical expansion of the Wheeler-DeWitt equation. Recently, such an investigation in the case of a real scalar field coupled to gravity has led to the prediction that the power at large…

Intermittency and Universality in Fully Developed Inviscid and Weakly Compressible Turbulent Flows

Crystallization to the Square Lattice for a Two-Body Potential

We consider two-dimensional zero-temperature systems of N particles to which we associate an energy of the form E[V](X):=?1?i<j?NV(|X(i)-X(j)|),where X(j) ? R represents the position of the particle j and V(r) ? R is the pairwise interaction energy potential of two particles placed at distance r…

Novel risk predictor for thrombus deposition in abdominal aortic aneurysms

The identification of the basic mechanisms responsible for cardiovascular diseases stands as one of the most challenging problems in modern medical research including various mechanisms which encompass a broad spectrum of space and time scales. Major implications for clinical practice and pre-…

An optimized D2Q37 Lattice Boltzmann code on GP-GPUs

We describe the implementation of a thermal compressible Lattice Boltzmann algorithm on an NVIDIA Tesla C2050 system based on the Fermi GP-GPU. We consider two different versions, including and not including reactive effects. We describe the overall organization of the algorithm and give details on…