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Accelerating f(T) gravity models constrained by recent cosmological dataApr 24 2012Generalised Teleparallel gravity, also referred to as f(T) gravity, has been recently proposed as an extended theory of gravitation able to give rise to an accelerated expansion in a matter only universe. The cosmic speed up is driven by an effective ... More

An updated analysis of two classes of f(R) theories of gravityJan 16 2012The observed accelerated cosmic expansion can be a signature of fourth\,-\,order gravity theories, where the acceleration of the Universe is a consequence of departures from Einstein General Relativity, rather than the sign of the existence of a fluid ... More

Detectability of Torsion Gravity via Galaxy Clustering and Cosmic Shear MeasurementsNov 05 2013Apr 10 2014Alterations of the gravity Lagrangian introduced in modified torsion gravity theories---also referred to as $f(T)$ gravity---allows for an accelerated expansion in a matter dominated Universe. In this framework, the cosmic speed up is driven by an effective ... More

Cosmography of f(R) - brane cosmologyOct 07 2010Cosmography is a useful tool to constrain cosmological models, in particular dark energy models. In the case of modified theories of gravity, where the equations of motion are generally quite complicated, cosmography can contribute to select realistic ... More

Increasing the Lensing Figure of Merit through Higher Order Convergence MomentsFeb 08 2018The unprecedented quality, the increased dataset, and the wide area of ongoing and near future weak lensing surveys allows to move beyond the standard two points statistics thus making worthwhile to investigate higher order probes. As an interesting step ... More

Averaging procedure in variable-G cosmologiesMay 08 2008Oct 20 2008Previous work in the literature had built a formalism for spatially averaged equations for the scale factor, giving rise to an averaged Raychaudhuri equation and averaged Hamiltonian constraint, which involve a backreaction source term. The present paper ... More

Cosmological parameters from lenses distance ratioSep 22 2015Strong lensing provides popular techniques to investigate the mass distribution of intermediate redshift galaxies, testing galaxy evolution and formation scenarios. It especially probes the background cosmic expansion, hence constraining cosmological ... More

A thermodynamic point of view on dark energy modelsDec 06 2016We present a conjugate analysis of two different dark energy models investigating both their agreement with recent data and their thermodynamical properties. The successful match with the data allows to both constrain the model parameters and characterize ... More

Constraining f(R) theories with Type Ia Supernovae and Gamma Ray BurstsJul 27 2009Fourth - order gravity theories have received much interest in recent years thanks to their ability to provide an accelerated cosmic expansion in a matter only universe. In these theories, the Lagrangian density of the gravitational field has the form ... More

Testing a Phenomenologically Extended DGP Model with Upcoming Weak Lensing SurveysJan 13 2011A phenomenological extension of the well-known brane-world cosmology of Dvali, Gabadadze and Porrati (eDGP) has recently been proposed. In this model, a cosmological-constant-like term is explicitly present as a non-vanishing tension sigma on the brane, ... More

Constraining massive gravity with recent cosmological dataMay 08 2012A covariant formulation of a theory with a massive graviton and no negative energy state has been recently proposed as an alternative to the usual General Relativity framework. For a spatially flat homogenous and isotropic universe, the theory introduces ... More

Hints for families of GRBs improving the Hubble diagramJun 23 2013As soon as their extragalactic origins were established, the hope to make Gamma - Ray Bursts (GRBs) standardizeable candles to probe the very high - z universe has opened the search for scaling relations between redshift independent observable quantities ... More

Gamma-ray bursts as cosmological probes: LambdaCDM vs. conformal gravityMar 28 2011Oct 11 2011LambdaCDM, for the currently preferred cosmological density Omega_0 and cosmological constant Omega_Lambda, predicts that the Universe expansion decelerates from early times to redshift z~0.9 and accelerates at later times. On the contrary, the cosmological ... More

Tomography from the Next Generation of Cosmic Shear Experiments for Viable f(R) ModelsApr 14 2011Jul 15 2011We present the cosmic shear signal predicted by two viable cosmological models in the framework of modified-action f(R) theories. We use f(R) models where the current accelerated expansion of the Universe is a direct consequence of the modified gravitational ... More

The leading chiral electromagnetic correction to the nonleptonic Delta I = 3/2 amplitude in kaon decaysOct 26 1998Jan 05 1999In kaon decay, electromagnetic radiative corrections can generate shifts in the apparent Delta I = 3/2 amplitude of order alpha A_0/A_2 ~ 22 alpha. In order to know the true Delta I = 3/2 amplitude for comparison with lattice calculations and phenomenology, ... More

Dimension-eight Operators in the Weak OPEJul 18 2000We expose a potential flaw in standard treatments of weak decay amplitudes, including that of epsilon'/epsilon. We show that (contrary to conventional wisdom) dimension-eight operators do contribute to weak amplitudes, at order G_F alpha_s and without ... More

Spiral galaxies rotation curves in the Horava - Lifshitz gravity theoryFeb 10 2012We focus on a modified version of Horava - Lifschitz theory and, in particular, we consider the impact of its weak - field static spherically symmetric limit on the galaxy dynamics. In a previous paper, we used the modified gravitational potential obtained ... More

Color and stellar population gradients in galaxies. Correlation with massApr 27 2010We analyze the color gradients (CGs) of ~50000 nearby SDSS galaxies. From synthetic spectral models based on a simplified star formation recipe, we derive the mean spectral properties, and explain the observed radial trends of the color as gradients of ... More

Testing the distance duality relation with present and future dataMay 09 2012The assumptions that "light propagates along null geodesics of the spacetime metric" and "the number of photons is conserved along the light path" lead to the distance duality relation (DDR), $\eta = D_L(z) (1 + z)^{-2}/D_A(z) = 1$, with $D_L(z)$ and ... More

Halting eternal acceleration with an effective negative cosmological constantMay 09 2008In order to solve the problem of eternal acceleration, a model has been recently proposed including both a negative cosmological constant $\Lambda$ and a scalar field evolving under the action of an exponential potential. We further explore this model ... More

Measurement of the halo bias from stacked shear profiles of galaxy clustersFeb 19 2014We present the observational evidence of the 2-halo term in the stacked shear profile of a sample of about 1200 optically selected galaxy clusters based on imaging data and the public shear catalog from the CFHTLenS. We find that the halo bias, a measure ... More

On the shear estimation bias induced by the spatial variation of colour across galaxy profilesNov 21 2012The spatial variation of the colour of a galaxy may introduce a bias in the measurement of its shape if the PSF profile depends on wavelength. We study how this bias depends on the properties of the PSF and the galaxies themselves. The bias depends on ... More

The power spectrum of systematics in cosmic shear tomography and the bias on cosmological parametersJul 18 2013Cosmic shear tomography has emerged as one of the most promising tools to both investigate the nature of dark energy and discriminate between General Relativity and modified gravity theories. In order to successfully achieve these goals, systematics in ... More

No need for dark matter in galaxy clusters within Galileon theoryJul 09 2016Modified gravity theories with a screening mechanism have acquired much interest recently in the quest for a viable alternative to General Relativity on cosmological scales, given their intrinsic property of being able to pass Solar System scale tests ... More

Improving lensing cluster mass estimate with flexionJul 20 2016Gravitational lensing has long been considered as a valuable tool to determine the total mass of galaxy clusters. The shear profile as inferred from the statistics of ellipticity of background galaxies allows to probe the cluster intermediate and outer ... More

RG generated fermion massJan 15 2001Chiral symmetry breaking in a purely fermionic theory is investigated by the help of the renormalization group method. The RG equation for the running mass $m_k$ admits a solution with vanishing bare mass and finite physical mass. The running Fermi coupling ... More

Interaction and observation: categorical semantics of reactive systems trough dialgebrasSep 26 2012Jun 03 2013We use dialgebras, generalising both algebras and coalgebras, as a complement of the standard coalgebraic framework, aimed at describing the semantics of an interactive system by the means of reaction rules. In this model, interaction is built-in, and ... More

Phenomenology of SIDIS unpolarized cross sections and azimuthal asymmetriesMar 28 2012I review the phenomenology of unpolarized cross sections and azimuthal asymmetries in semi-inclusive deeply inelastic scattering (SIDIS). The general theoretical framework is presented and the validity of the Gaussian model is discussed. A brief account ... More

Phenomenology of transverse-spin and transverse-momentum effects in hard processesFeb 03 2011Some recent analyses of single-spin and azimuthal asymmetries in SIDIS and Drell-Yan processes, focusing in particular on Collins, Sivers and Boer-Mulders effects, are briefly reviewed. The perspectives for future phenomenological studies are also outlined. ... More

Understanding transversity: present and futureFeb 11 2005I review the present state of knowledge concerning transversity distributions and related observables. In particular, I discuss the phenomenology of transverse asymmetries in e p\uparrow, p p\uparrow, p\uparrow p\uparrow and pbar \uparrow p\uparrow scattering, ... More

On the lexicographic representation of numbersMay 03 2015It is proven that, contrarily to the common belief, the notion of zero is not necessary for having positional representations of numbers. Namely, for any positive integer $k$, a positional representation with the symbols for $1, 2, \ldots, k$ is given ... More

Radiative Corrections in K, D, and B decaysJun 01 2006In this talk I review recent developments in the calculation of radiative corrections to $K, D, B$ meson decays and discuss their impact on precision phenomenology.

Non perturbative renormalization group potentials and quintessenceFeb 01 2000Feb 02 2000New solutions to the non perturbative renormalization group equation for the effective action of a scalar field theory in the Local Potential Approximation having the exponential form $e^{\pm\phi}$ are found. This result could be relevant for those quintessence ... More

Vector Quantization for Machine VisionMar 30 2016This paper shows how to reduce the computational cost for a variety of common machine vision tasks by operating directly in the compressed domain, particularly in the context of hardware acceleration. Pyramid Vector Quantization (PVQ) is the compression ... More

Attenuation of shear sound waves in jammed solidsSep 08 2010We study the attenuation of long-wavelength shear sound waves propagating through model jammed packings of frictionless soft spheres interacting with repulsive springs. The elastic attenuation coefficient, $\alpha(\omega)$, of transverse phonons of low ... More

A computational framework for microstructural modelling of polycrystalline materials with damage and failureFeb 06 2018In the present thesis, a computational framework for the analysis of the deformation and damage phenomena occurring at the micro-scale of polycrystalline materials is presented. Micro-mechanics studies are commonly performed using the Finite Element Method ... More

Financial LPPL Bubbles with Mean-Reverting Noise in the Frequency DomainSep 24 2010Jan 30 2011The log-periodic power law (LPPL) is a model of asset prices during endogenous bubbles. A major open issue is to verify the presence of LPPL in price sequences and to estimate the LPPL parameters. Estimation is complicated by the fact that daily LPPL ... More

On the Optimality of Simple Schedules for Networks with Multiple Half-Duplex RelaysDec 05 2014This paper studies networks with N half-duplex relays assisting the communication between a source and a destination. In ISIT'12 Brahma, \"{O}zg\"{u}r and Fragouli conjectured that in Gaussian half-duplex diamond networks (i.e., without a direct link ... More

Generic I0 at $\aleph_ω$Sep 26 2016In this paper it is introduced a generic large cardinal akin to I0, and its consequences are analyzed in the case that $\aleph_\omega$ is such a generic large cardinal. In this case $\aleph_\omega$ is J\'{o}nsson, and in a choiceless inner model many ... More

Concentrating solutions for a class of nonlinear fractional Schrödinger equations in $\mathbb{R}^{N}$Dec 07 2016We deal with the existence of positive solutions for the following fractional Schr\"odinger equation $$ \varepsilon ^{2s} (-\Delta)^{s} u + V(x) u = f(u) \mbox{ in } \mathbb{R}^{N}, $$ where $\varepsilon>0$ is a parameter, $s\in (0, 1)$, $N>2s$, $(-\Delta)^{s}$ ... More

Fractional $p\&q$ Laplacian problems in $\mathbb{R}^{N}$ with critical growthJan 31 2018We deal with the following nonlinear problem involving fractional $p$ and $q$-Laplacians: \begin{equation*} (-\Delta)^{s}_{p}u+(-\Delta)^{s}_{q}u+|u|^{p-2}u+|u|^{q-2}u=\lambda f(u)+|u|^{q^{*}_{s}-2}u \mbox{ in } \mathbb{R}^{N} \end{equation*} where $s\in ... More

Laser from a Manybody Correlated MediumDec 07 2015Mar 11 2016We consider a non-equilibrium system of interacting emitters described by the XXZ model, whose excitonic transitions are spatially and spectrally coupled to a single mode cavity. We demonstrate that the output radiation field is sensitive to an interplay ... More

Quantum CavitationJun 05 2010We consider the theoretical setting of a superfluid like 3He in a rotating container, which is set between the two layers of a type-II superconductor. We describe the superfluid vortices as a 2-dimensional Ising-like model on a triangular lattice in presence ... More

Slope evolution of GRB correlations and cosmologyAug 08 2013Gamma -ray bursts (GRBs) observed up to redshifts $z>9.4$ can be used as possible probes to test cosmological models. Here we show how changes of the slope of the {\it luminosity $L^*_X$ -break time $T^*_a$} correlation in GRB afterglows, hereafter the ... More

Accelerating cosmology in Rastall's theoryJun 22 2009Oct 08 2010In an attempt to look for a viable mechanism leading to a present-day accelerated expansion, we investigate the possibility that the observed cosmic speed up may be recovered in the framework of the Rastall's theory, relying on the non-conservativity ... More

Pixel lensing observations towards globular clustersApr 15 2003It has been suggested that a monitoring program employing the pixel lensing method to search for microlensing events towards galactic globular clusters may increase the statistics and discriminate among different halo models. Stimulated by this proposal, ... More

Uniform resolvent convergence for strip with fast oscillating boundaryJun 08 2012May 07 2013In a planar infinite strip with a fast oscillating boundary we consider an elliptic operator assuming that both the period and the amplitude of the oscillations are small. On the oscillating boundary we impose Dirichlet, Neumann or Robin boundary condition. ... More

3-D Self-Assembled Soi Mems: An Example of Multiphysics SimulationNov 21 2007MEMS devices are typical systems where multiphysics simulations are unavoidable. In this work, we present possible applications of 3-D self-assembled SOI (Silicon-on-Insulator) MEMS such as, for instance, thermal actuators and flow sensors. The numerical ... More

Experimental evidence of guided resonances in photonic crystals with aperiodically-ordered supercellsAug 20 2010Oct 28 2010We report on the first experimental evidence of guided resonances (GRs) in photonic crystal slabs based on aperiodically-ordered supercells. Using the Ammann-Beenker (quasiperiodic, 8-fold symmetric) tiling geometry, we present our study on the fabrication, ... More

Systematic biases on galaxy haloes parameters from Yukawa-like gravitational potentialsFeb 04 2011A viable alternative to the dark energy as a solution of the cosmic speed up problem is represented by Extended Theories of Gravity. Should this be indeed the case, there will be an impact not only on cosmological scales, but also at any scale, from the ... More

On the Capacity of the Two-user Gaussian Causal Cognitive Interference ChannelJul 23 2012Sep 30 2013This paper considers the two-user Gaussian Causal Cognitive Interference Channel (GCCIC), which consists of two source-destination pairs that share the same channel and where one full-duplex cognitive source can causally learn the message of the primary ... More

Phenomenology of Minimal Lepton Flavor ViolationJan 13 2006Jan 13 2006We extend the effective theory of Minimal Lepton Flavor Violation (MLFV) by including four-lepton operators. We compute the rates for mu -> 3 e and tau -> 3 ell decays and point out several new ways to test the hypothesis of MLFV. We also investigate ... More

Level Crossings in a PT-symmetric Double WellJun 04 2015We consider a \textit{PT}-symmetric cubic oscillator with an imaginary double well. We prove the existence of an infinite number of level crossings with a definite selection rule. Decreasing the positive parameter $\hbar$ from large values, at a value ... More

Slice regular semigroupsMay 05 2016May 17 2016In this paper we introduce the notion of slice regular right linear semigroup in a quaternionic Banach space. It is an operatorial function which is slice regular (a noncommutative counterpart of analyticity) and which satisfies a noncommutative semigroup ... More

Precision physics with heavy-flavoured hadronsOct 15 2015The understanding of flavour dynamics is one of the key aims of elementary particle physics. The last 15 years have witnessed the triumph of the Kobayashi-Maskawa mechanism, which describes all flavour changing transitions of quarks in the Standard Model. ... More

A general tool for consistency results related to I1Oct 12 2015In this paper we provide a general tool to prove the consistency of $I1(\lambda)$ with various combinatorial properties at $\lambda$ typical at settings with $2^\lambda>\lambda^+$, that does not need a profound knowledge of the forcing notions involved. ... More

Stone duality above dimension zero: Axiomatising the algebraic theory of C(X)Aug 31 2015Oct 17 2016It has been known since the work of Duskin and Pelletier four decades ago that KH^op, the category opposite to compact Hausdorff spaces and continuous maps, is monadic over the category of sets. It follows that KH^op is equivalent to a possibly infinitary ... More

Spectral correlations among interfering nonidentical photons in universal linear opticsJun 17 2017Jun 30 2017Multiphoton quantum interference underpins fundamental tests of quantum mechanics and quantum technologies. Consequently, the detrimental effect of photon distinguishability in multiphoton interference experiments can be catastrophic. Here, we theoretically ... More

Surreal numbers with derivation, Hardy fields and transseries: a surveyAug 11 2016The present article surveys surreal numbers with an informal approach, from their very first definition to their structure of universal real closed analytic and exponential field. Then we proceed to give an overview of the recent achievements on equipping ... More

Nominal Cellular AutomataAug 11 2016The emerging field of Nominal Computation Theory is concerned with the theory of Nominal Sets and its applications to Computer Science. We investigate here the impact of nominal sets on the definition of Cellular Automata and on their computational capabilities, ... More

Stability, Higgs Boson Mass and New PhysicsJul 19 2013May 27 2014When the particle with mass $\sim 126$ GeV discovered at LHC is identified with the Higgs boson of the Standard Model, intriguing and challenging questions arise. Among them, the issue of the EW vacuum stability. We find that, despite claims to the contrary, ... More

Surreal numbers with derivation, Hardy fields and transseries: a surveyAug 11 2016Oct 23 2016The present article surveys surreal numbers with an informal approach, from their very first definition to their structure of universal real closed analytic and exponential field. Then we proceed to give an overview of the recent achievements on equipping ... More

Soft quantum vibrations of PT-symmetric nonlinear ion chainFeb 18 2013Nov 11 2013We theoretically study the quantum dynamics of transverse vibrations of a one-dimensional chain of trapped ions in harmonic potentials interacting via a Reggeon-type cubic nonlinearity that is nonunitary but preserves PT symmetry. We propose the notion ... More

Transseries as germs of surreal functionsMar 06 2017Oct 05 2017We show that \'Ecalle's transseries and their variants (LE and EL-series) can be interpreted as functions from positive infinite surreal numbers to surreal numbers. The same holds for a much larger class of formal series, here called omega-series. Omega-series ... More

Geometric background charge: dislocations on capillary bridgesJun 19 2012Recent experiments have shown that colloidal crystals confined to weakly curved capillary bridges introduce groups of dislocations organized into `pleats' as means to relieve the stress caused by the Gaussian curvature of the surface. We consider the ... More

Crystals and liquid crystals confined to curved geometriesJan 20 2014This review introduces the elasticity theory of two-dimensional crystals and nematic liquid crystals on curved surfaces, the energetics of topological defects (disclinations, dislocations and pleats) in these ordered phases, and the interaction of defects ... More

Neutrino flavor dynamics in post-bounce supernovae: the role of the electron componentApr 20 2012In this paper we study the dynamics of flavor transformation for neutrinos propagating in the very dense environment of astrophysical compact objects as Type II supernova in post collapse phase and proto-neutron stars. The analysis is based on the generalized ... More

Multifractal structure of Ly$α$ clouds: An example with the spectrum of QSO 0055--26Mar 15 1996Ly$\alpha$ forests are usually associated with intergalactic gas clouds intercepting the quasar sight--line. Using as an example the Ly$\alpha$ forest of QSO 0055--26 ($z_{em} = 3.66$), we show that the probability of observing a line at the velocity ... More

Finite Temperature Behaviour of O'KKLT ModelApr 04 2008We summarize our work on the O'Raifeartaigh uplifted KKLT model at finite temperature. We study the system for parameter values for which the zero temperature potential for the volume modulus has a dS minimum. The temperature-dependent part of the effective ... More

A note on isospin violation in Pl2(gamma) decaysFeb 02 2011We discuss the size of isospin violating effects of both electromagnetic (e \neq 0) and strong (m_u \neq m_d) origin in P_{\ell 2 (\gamma)} decays. Our results are relevant for the extraction of |V_{us}/V_{ud}| from the measured ratio of the K_{\mu 2 ... More

On the Betti numbers of some semigroup ringsNov 06 2011For any numerical semigroup $S$, there are infinitely many numerical symmetric semigroups $T$ such that $S=\frac{T}{2}$ is their half. We are studying the Betti numbers of the numerical semigroup ring $K[T]$ when $S$ is a 3-generated numerical semigroup ... More

Multiple solutions for a class of nonhomogeneous fractional Schrödinger equations in $\mathbb{R}^{N}$Dec 07 2016This paper is concerned with the following fractional Schr\"odinger equation \begin{equation*} \left\{ \begin{array}{ll} (-\Delta)^{s} u+u= k(x)f(u)+h(x) \mbox{ in } \mathbb{R}^{N} u\in H^{s}(\mathbb{R}^{N}), \, u>0 \mbox{ in } \mathbb{R}^{N}, \end{array} ... More

Toward quantum computational supremacy of boson sampling with random overlap in the photonic spectraJan 11 2018Multiphoton interference is at the very heart of quantum foundations and applications in quantum sensing and information processing. In particular, boson sampling experiments have the potential to demonstrate quantum computational supremacy while only ... More

Systematics in the Gamma Ray Bursts Hubble diagramMay 05 2011Thanks to their enormous energy release which allows to detect them up to very high redshift, Gamma Rays Bursts (GRBs) have recently attracted a lot of interest to probe the Hubble diagram (HD) deep into the matter dominated era and hence complement Type ... More

Dark energy and dark matter as curvature effectsFeb 15 2006Mar 20 2006Astrophysical observations are pointing out huge amounts of dark matter and dark energy needed to explain the observed large scale structures and cosmic accelerating expansion. Up to now, no experimental evidence has been found, at fundamental level, ... More

Reconciling dark energy models with f(R) theoriesJan 20 2005Higher order theories of gravity have recently attracted a lot of interest as alternative candidates to explain the observed cosmic acceleration without the need of introducing any scalar field. A critical ingredient is the choice of the function f(R) ... More

Experimental and phenomenological comparison between Piezonuclear reactions and Condensed Matter Nuclear Science phenomenologyMar 06 2011The purpose of this paper is to place side by side the experimental results of Piezonu- clear reactions, which have been recently unveiled, and those collected during the last twenty years of experiments on low energy nuclear reactions (LENR). We will ... More

Gravitational lensing in fourth order gravityApr 20 2006Gravitational lensing is investigated in the weak field limit of fourth order gravity in which the Lagrangian of the gravitational field is modified by replacing the Ricci scalar curvature R with an analytical expression $f(R)$. Considering the case of ... More

Unified dark energy models : a phenomenological approachFeb 10 2004A phenomenological approach is proposed to the problem of universe accelerated expansion and of the dark energy nature. A general class of models is introduced whose energy density depends on the redshift $z$ in such a way that a smooth transition among ... More

Possible Experimental Evidence for Violation of Standard Electrodynamics, de Broglie Pilot Wave and Spacetime DeformationJun 28 2011We report and discuss the results of double-slit-like experiments in the infrared range, which evidence an anomalous behaviour of photon systems under particular (energy and space) constraints. These outcomes apparently disagree both with standard quantum ... More

Neutrinos superluminality and Local Lorentz InvarianceSep 24 2011Mar 02 2012The recent measurement of the neutrino velocity with the OPERA detector in the CNGS beam, on whose basis it was found that (v-c)/c = (2.48 \pm 0.28 (stat.) \pm 0.30 (sys.)) 10e-5, does not contain any significant violation of Local Lorentz Invariance ... More

The Principle of Solidarity: Geometrical Description of InteractionsSep 08 2011We discuss the possibility of geometrizing interactions by exploiting the "principle of solidarity" between space-time and the physical phenomena occurring in it (formulated by the Italian matematician B. Finzi in 1955). This is accomplished by means ... More

Speeding-up Thorium decayOct 26 2007We show that cavitation of a solution of thorium-228 in water induces its transformation at a rate 10000 times faster than the natural radioactive decay would do. This result agrees with the alteration of the secular equilibrium of thorium-234 obtained ... More

Néron-Severi group of a general hypersurfaceJun 24 2015Jan 11 2016In this paper we extend the well known theorem of Angelo Lopez concerning the Picard group of the general space projective surface containing a given smooth projective curve, to the intermediate N\'eron-Severi group of a general hypersurface in any smooth ... More

Factoriality and Neron-Severi groups of a projective codimension two complete intersection with isolated singularitiesMay 12 2006For a projective variety $Z$ and for any integer $p$, define the $p$-th N\'eron-Severi group $NS_p(Z)$ of $Z$ as the image of the cycle map $A_{p}(Z)\to H_{2p}(Z; \mathbb{C})$. Now let $X\subset \Ps^{2m+1}$ ($m\geq 1$) be a projective variety of dimension ... More

Simultaneous observation of gravitational and electromagnetic wavesApr 28 2016Assuming that the short gamma-ray burst detected by the Fermi Gamma-Ray Space Telescope about 0.4 seconds after the gravitational waves observed by the LIGO and VIRGO Collaborations originated from the same black hole merger event, we perform a model-independent ... More

Periodic solutions for nonlocal fractional equationsAug 13 2016The purpose of this paper is to study the existence of (weak) periodic solutions for nonlocal fractional equations with periodic boundary conditions. These equations have a variational structure and, by applying a critical point result coming out from ... More

On the existence of a Gysin morphism for the Blow-up of an ordinary singularityMar 12 2016Jun 01 2016In this paper we characterize the Blowing-up maps of ordinary singularities for which there exists a natural Gysin morphism, i.e. a bivariant class $\theta \in Hom_{D(Y)}(R\pi_*\mathbb Q_X, \mathbb Q_Y)$, compatible with pullback and with restriction ... More

Monodromy of a family of hypersurfacesMar 11 2008Apr 28 2009Let $Y$ be an $(m+1)$-dimensional irreducible smooth complex projective variety embedded in a projective space. Let $Z$ be a closed subscheme of $Y$, and $\delta$ be a positive integer such that $\mathcal I_{Z,Y}(\delta)$ is generated by global sections. ... More

A speciality Theorem for curves in $\mathbb{P}^5$ contained in Noether-Lefschetz general fourfoldsNov 17 2016Let $C\subset \mathbb P^r$ be an integral projective curve. One defines the speciality index $e(C)$ of $C$ as the maximal integer $t$ such that $h^0(C,\omega_C(-t))>0$, where $\omega_C$ denotes the dualizing sheaf of $C$. In the present paper we consider ... More

Plucker-Clebsch formula in higher dimensionJan 27 2010Let $S\subset\Ps^r$ ($r\geq 5$) be a nondegenerate, irreducible, smooth, complex, projective surface of degree $d$. Let $\delta_S$ be the number of double points of a general projection of $S$ to $\Ps^4$. In the present paper we prove that $ \delta_S\leq{\binom ... More

A lower bound for $K^2_S$Jan 25 2016Let $(S,\mathcal L)$ be a smooth, irreducible, projective, complex surface, polarized by a very ample line bundle $\mathcal L$ of degree $d > 35$. In this paper we prove that $K^2_S\geq -d(d-6)$. The bound is sharp, and $K^2_S=-d(d-6)$ if and only if ... More

Low surface brightness galaxies rotation curves in the low energy limit of $R^n$ gravity : no need for dark matter?Mar 20 2006Dec 13 2006We investigate the possibility that the observed flatness of the rotation curves of spiral galaxies is not an evidence for the existence of dark matter haloes, but rather a signal of the breakdown of General Relativity. To this aim, we consider power ... More

Cosmography of f(R) gravityFeb 12 2008Jul 08 2008It is nowadays accepted that the universe is undergoing a phase of accelerated expansion as tested by the Hubble diagram of Type Ia Supernovae (SNeIa) and several LSS observations. Future SNeIa surveys and other probes will make it possible to better ... More

Lens modelling and H_0 estimate in quadruply lensed systemsJul 07 2004We present a numerical method to estimate the lensing parameters and the Hubble constant H_0 from quadruply imaged gravitational lens systems. The lens galaxy is modeled using both separable deflection potentials and constant mass-to-light ratio profiles, ... More

Spherical galaxy models with power law logarithmic slopeJan 10 2005We present a new family of spherically symmetric models for the luminous components of elliptical and spiral galaxies and their dark matter haloes. Our starting point is a general expression for the logarithmic slope $\alpha(r) = d\log{\rho}/d\log{r}$ ... More

Remarks on the cavitation of Thorium-228Jan 29 2010Jan 31 2010In this short note we would like to provide some useful remarks on our previous work about the piezonuclear decay of Thorium and in general about the methods and protocols that we used in the experiments on piezonuclear reactions. The purpose of these ... More

Dynamical and gravitational lensing properties of a new phenomenological model of elliptical galaxiesNov 21 2006Recent observations of the line of sight velocity profile of elliptical galaxies have furnished controversial results with some works favouring the presence of a large amount of dark matter in the outer regions and others arguing in favour of no dark ... More

Some astrophysical implications of dark matter and gas profiles in a new galaxy clusters modelAug 09 2004The structure of the dark matter and the thermodynamical status of the hot gas in galaxy clusters is an interesting and widely discussed topic in modern astrophysics. Recently, Rasia et al. (2004) have proposed a new dynamical model for the mass density ... More

Inflessence: a phenomenological model for inflationary quintessenceJun 16 2005We present a phenomenologically motivated model which is able to give rise both to an inflationary epoch and to the present day cosmic acceleration. We introduce an approach where the energy density depends on the scale factor $a$ in such a way that a ... More