Results for "Silvio C. Ferreira"

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Eden clusters in three-dimensions and the Kardar-Parisi-Zhang universality classSep 19 2012Oct 25 2012We present large-scale simulations of radial Eden clusters in three-dimensions and show that the growth exponent is in agreement with the value $\beta=0.242$ accepted for the Kardar-Parisi-Zhang (KPZ) universality class. Our results refute a recent assertion ... More
Universality of the contact process with random dilutionJan 05 2011We present quasi-stationary simulations of the two-dimensional contact process with quenched disorder included through the random dilution of a fraction of the lattice sites (these sites are not susceptible to infection). Our results strongly indicate ... More
Effects of local population structure in a reaction-diffusion model of a contact process on metapopulation networksMay 21 2013Nov 08 2013We investigate the effects of local population structure in reaction-diffusion processes representing a contact process (CP) on metapopulations represented as complex networks. Considering a model in which the nodes of a large scale network represent ... More
Non-universal parameters, corrections and universality in Kardar-Parisi-Zhang growthFeb 15 2013Apr 12 2013We present a comprehensive numerical investigation of non-universal parameters and corrections related to interface fluctuations of models belonging to the Kardar-Parisi-Zhang (KPZ) universality class, in d=1+1, for both flat and curved geometries. We ... More
On the origins of scaling corrections in ballistic growth modelsSep 08 2014We study the ballistic deposition and the grain deposition models on two-dimensional substrates. Using the Kardar-Parisi-Zhang (KPZ) ansatz for height fluctuations, we show that the main contribution to the intrinsic width, which causes strong corrections ... More
Effects of a kinetic barrier on limited-mobility interface growth modelsFeb 08 2019Feb 13 2019The role played by a kinetic barrier originated by out-of-plane step edge diffusion, introduced in [Leal \textit{et al.}, \href{https://doi.org/10.1088/0953-8984/23/29/292201}{J. Phys. Condens. Matter \textbf{23}, 292201 (2011)}], is investigated in the ... More
Quantifying echo chamber effects in information spreading over political communication networksJan 11 2019Echo chambers in online social networks, in which users prefer to interact only with ideologically-aligned peers, are believed to facilitate misinformation spreading and contribute to radicalize political discourse. In this paper, we gauge the effects ... More
Universality of fluctuations in the Kardar-Parisi-Zhang class in high dimensions and its upper critical dimensionMay 05 2014Jul 30 2014We show that the theoretical machinery developed for the Kardar-Parisi-Zhang (KPZ) class in low dimensions are obeyed by the restricted solid-on-solid (RSOS) model for substrates with dimensions up to $d=6$. Analyzing different restriction conditions, ... More
Sampling methods for the quasistationary regime of epidemic processes on regular and complex networksMay 31 2016A major hurdle in the simulation of the steady state of epidemic processes is that the system will unavoidably visit an absorbing, disease-free state at sufficiently long times due to the finite size of the networks where epidemics evolves. In the present ... More
Anomalous scaling and super-roughness in the growth of CdTe polycrystalline filmsJan 06 2011CdTe films grown on glass substrates covered by fluorine doped tin oxide by Hot Wall Epitaxy (HWE) were studied through the interface dynamical scaling theory. Direct measures of the dynamical exponent revealed an intrinsically anomalous scaling characterized ... More
Multiscale model for the effects of adaptive immunity suppression on the viral therapy of cancerFeb 15 2013Oncolytic virotherapy - the use of viruses that specifically kill tumor cells - is an innovative and highly promising route for treating cancer. However, its therapeutic outcomes are mainly impaired by the host immune response to the viral infection. ... More
Hallmarks of the Kardar-Parisi-Zhang universality class elicited by scanning probe microscopyJan 18 2016Sep 17 2016Scanning probe microscopy (SPM) is a fundamental technique for the analysis of surfaces. In the present work, the interface statistics of surfaces scanned with a probe tip was analyzed for both \textit{in silico} and experimental systems that \textit{do ... More
Local roughness exponent in the nonlinear molecular-beam-epitaxy universality class in one-dimensionDec 07 2018We report local roughness exponents, $\alpha_{\text{loc}}$, for three interface growth models in one dimension which are believed to belong the non-linear molecular-beam-epitaxy (nMBE) universality class represented by the Villain-Lais-Das Sarma (VLDS) ... More
Quantum field theory on rotating black hole spacetimesSep 25 2015This thesis is concerned with the development of a general method to compute renormalised local observables for quantum matter fields, in a given quantum state, on a rotating black hole spacetime. The rotating black hole may be surrounded by a Dirichlet ... More
On the $3 \times 3$ magic square constructed with nine distinct square numbersApr 24 2015Jun 26 2015A proof that there is no $3 \times 3$ magic square constructed with nine distinct square numbers is given.
Observational limits on the spin-down torque of Accretion Powered Stellar WindsDec 15 2010The rotation period of classical T Tauri stars (CTTS) represents a longstanding puzzle. While young low-mass stars show a wide range of rotation periods, many CTTS are slow rotators, spinning at a small fraction of break-up, and their rotation period ... More
The Antinomy of the Liar and ProvabilityJun 03 2008This work evidences that a sentence cannot be denominated by P and written as P IS NOT TRUE. It demonstrates that in a system in which Q denominates the sentence Q IS NOT PROVABLE it is not provable that Q is true and not provable.
Renormalized vacuum polarization of rotating black holesFeb 04 2015May 05 2015Quantum field theory on rotating black hole spacetimes is plagued with technical difficulties. Here, we describe a general method to renormalize and compute the vacuum polarization of a quantum field in the Hartle-Hawking state on rotating black holes. ... More
The non-trivial zeros of Riemann's zeta-functionMay 27 2004Apr 26 2015A proof of the Riemann hypothesis using the reflection principle is presented.
A proof of the non existence of Frey curves without using TSW theoremNov 19 2002Jul 19 2013Fermat's Last Theorem (FLT) implies that the Frey curves do not exist. A proof of FLT independent of proved Taniyama-Shimura-Weil conjecture is presented.
On Goldbach's ConjectureSep 18 2002It is shown that if every odd integer $n > 5$ is the sum of three primes, then every even integer $n > 2$ is the sum of two primes. A conditional proof of Goldbach's conjecture, based on Cram\'er's conjecture, is presented. Theoretical and experimental ... More
Infinite and natural numbersFeb 14 2002The infinite numbers of the set M of finite and infinite natural numbers are defined starting from the sequence 0\Phi, where 0 is the first natural number, \Phi is a succession of symbols S and xS is the successor of the natural number x. The concept ... More
Williams and Bjerknes model with growth limitationNov 19 2001Williams and Bjerknes proposed a simple stochastic growth model to describe the tumor growth in the basal layer of an epithelium. In this work we generalize this model by including the possibility of saturation in the tumor growth as it is clinically ... More
Stability of warped AdS3 black holes in Topologically Massive Gravity under scalar perturbationsApr 22 2013May 24 2013We demonstrate that the warped AdS3 black hole solutions of Topologically Massive Gravity are classically stable against massive scalar field perturbations by analysing the quasinormal and bound state modes of the scalar field. In particular, it is found ... More
Critical behavior of the contact process on small-world networksJul 23 2013Nov 11 2013We investigate the role of clustering on the critical behavior of the contact process (CP) on small-world networks using the Watts-Strogatz (WS) network model with an edge rewiring probability p. The critical point is well predicted by a homogeneous cluster-approximation ... More
Bit Flipping Moment Balancing Schemes for Insertion, Deletion and Substitution Error CorrectionJan 23 2019In this paper, two moment balancing schemes, namely a variable index scheme and a fixed index scheme, for either single insertion/deletion error correction or multiple substitution error correction are introduced for coded sequences originally developed ... More
Thermodynamics of nonsingular bouncing universesSep 12 2015Feb 05 2016Homogeneous and isotropic, nonsingular, bouncing world models are designed to evade the initial singularity at the beginning of the cosmic expansion. Here, we study the thermodynamics of the subset of these models governed by general relativity. Considering ... More
Griffiths effects of the susceptible-infected-susceptible epidemic model on random power-law networksDec 16 2015Mar 28 2016We provide numerical evidence for slow dynamics of the susceptible-infected-susceptible model evolving on finite-size random networks with power-law degree distributions. Extensive simulations were done by averaging the activity density over many realizations ... More
Scaling, cumulant ratios and height distribution of the ballistic deposition in 3+1 and 4+1 dimensionsMar 28 2016Apr 07 2016We investigate the origin of the scaling corrections in ballistic deposition models in high dimensions using the method proposed by Alves \textit{et al}. [Phys Rev. E \textbf{90}, 052405 (20014)] in $d=2+1$ dimensions, where the intrinsic width associated ... More
Pair quenched mean-field theory for the susceptible-infected-susceptible model on complex networksMay 22 2013Sep 10 2013We present a quenched mean-field (QMF) theory for the dynamics of the susceptible-infected-susceptible (SIS) epidemic model on complex networks where dynamical correlations between connected vertices are taken into account by means of a pair approximation. ... More
Critical behavior of the contact process in a multiscale networkJan 06 2011Inspired by dengue and yellow fever epidemics, we investigated the contact process (CP) in a multiscale network constituted by one-dimensional chains connected through a Barab\'asi-Albert scale-free network. In addition to the CP dynamics inside the chains, ... More
Multiple phase transitions of the susceptible-infected-susceptible epidemic model on complex networksMar 26 2014Jan 09 2015The epidemic threshold of the susceptible-infected-susceptible (SIS) dynamics on random networks having a power law degree distribution with exponent $\gamma>3$ has been investigated using different mean-field approaches, which predict different outcomes. ... More
Quasi-stationary analysis of the contact process on annealed scale-free networksMay 17 2011We present an analysis of the quasi-stationary (QS) state of the contact process (CP) on annealed scale-free networks using a mapping of the CP dynamics in a one-step processes and analyzing numerically and analytically the corresponding master equation. ... More
Faceted anomalous scaling in the epitaxial growth of semiconductor filmsJan 07 2011May 17 2011We apply the generic dynamical scaling theory (GDST) to the surfaces of CdTe polycrystalline films grown in glass substrates. The analysed data were obtained with a stylus profiler with an estimated resolution lateral resolution of $l_c=0.3 \mu$m. Both ... More
Heterogeneous pair-approximation for the contact process on complex networksFeb 12 2014May 07 2014Recent works have shown that the contact process running on the top of highly heterogeneous random networks is described by the heterogeneous mean-field theory. However, some important aspects as the transition point and strong corrections to the finite-size ... More
ALGORAND: The Efficient and Democratic LedgerJul 05 2016Aug 24 2016Algorand is a truly decentralized, new, and secure way to manage a shared ledger. Unlike prior approaches based on {\em proof of work}, it requires a negligible amount of computation, and generates a transaction history that does not fork with overwhelmingly ... More
The index of symmetry of three-dimensional Lie groups with a left-invariant metricApr 17 2016Jul 11 2016We determine the index of symmetry of 3-dimensional unimodular Lie groups with a left-invariant metric. In particular, we prove that every 3-dimensional unimodular Lie group admits a left-invariant metric with positive index of symmetry. We also study ... More
ALGORAND: The Efficient and Democratic LedgerJul 05 2016Oct 03 2016Algorand is a truly decentralized, new, and secure way to manage a shared ledger. Unlike prior approaches based on {\em proof of work}, it requires a negligible amount of computation, and generates a transaction history that does not fork with overwhelmingly ... More
The distribution of symmetry of a naturally reductive nilpotent Lie groupOct 13 2017We show that the distribution of symmetry of a naturally reductive nilpotent Lie group coincides with the invariant distribution induced by the set of fixed vectors of the isotropy. This extends a known result on compact naturally reductive spaces. We ... More
Manifolds admitting a metric with co-index of symmetry 4Dec 12 2018By a recent result, it is known that compact homogeneous spaces with co-index of symmetry 4 are quotients of a semisimple Lie group of dimension at most 10. In this paper we determine exactly which ones of these spaces actually admit such a metric. For ... More
Existence of solutions for a class of $p(x)$-laplacian equations involving a concave-convex nonlinearity with critical growth in $\mathbb{R}^{N}$Apr 26 2013Dec 11 2013We prove the existence of solutions for a class of quasilinear problems involving variable exponents and with nonlinearity having critical growth. The main tool used is the variational method, more precisely, Ekeland's Variational Principle and the Mountain ... More
Evaluating and improving the cluster variation method entropy functional for Ising alloysJan 09 1998The success of the "Cluster Variation Method" (CVM) in reproducing quite accurately the free energies of Monte Carlo (MC) calculations on Ising models is explained in terms of identifying a cancellation of errors: We show that the CVM produces correlation ... More
Renormalized vacuum polarization on rotating warped AdS3 black holesOct 22 2014Jan 28 2015We compute the renormalized vacuum polarization of a massive scalar field in the Hartle-Hawking state on (2+1)-dimensional rotating, spacelike stretched black hole solutions to Topologically Massive Gravity, surrounded by a Dirichlet mirror that makes ... More
On the Schrödinger equation with singular potentialsJul 25 2013We study the Cauchy problem for the non-linear Schr\"odinger equation with singular potentials. For point-mass potential and nonperiodic case, we prove existence and asymptotic stability of global solutions in weak-L^{p} spaces. Specific interest is give ... More
Global well-posedness and asymptotic behavior for Navier-Stokes-Coriolis equations in homogeneous Besov spacesNov 08 2017We are concerned with the $3$D-Navier-Stokes equations with Coriolis force. Existence and uniqueness of global solutions in homogeneous Besov spaces are obtained for large speed of rotation. In the critical case of the regularity, we consider a suitable ... More
Hadamard states for a scalar field in anti-de Sitter spacetime with arbitrary boundary conditionsOct 04 2016Dec 16 2016We consider a real, massive scalar field on ${\rm PAdS}_{d+1}$, the Poincar\'e domain of the $(d+1)$-dimensional anti-de Sitter (AdS) spacetime. We first determine all admissible boundary conditions that can be applied on the conformal boundary, noting ... More
On the algebraic quantization of a massive scalar field in anti-de-Sitter spacetimeJan 25 2017Feb 16 2017We discuss the algebraic quantization of a real, massive scalar field in the Poincar\'e patch of the (d+1)-dimensional anti-de Sitter spacetime, with arbitrary boundary conditions. By using the functional formalism, we show that it is always possible ... More
Large scale magnetic fields in viscous resistive accretion disks. I. Ejection from weakly magnetized disksMar 23 2010Cold steady-state disk wind theory from near Keplerian accretion disks requires a large scale magnetic field at near equipartition strength. However the minimum magnetization has never been tested. We investigate the time evolution of an accretion disk ... More
Is it really possible to grow isotropic on-lattice diffusion-limited aggregates?Mar 08 2006In a recent paper (Bogoyavlenskiy V A 2002 \JPA \textbf{35} 2533), an algorithm aiming to generate isotropic clusters of the on-lattice diffusion-limited aggregation (DLA) model was proposed. The procedure consists of aggregation probabilities proportional ... More
Existence and stability of global large strong solutions for the Hall-MHD systemDec 30 2014Apr 26 2015We consider the 3D incompressible Hall-MHD system and prove a stability theorem for global large solutions under a suitable integrable hypothesis in which one of the parcels is linked to the Hall term. As a byproduct, a class of global strong solutions ... More
Anomalous tag diffusion in the asymmetric exclusion model with particles of arbitrary sizesApr 03 2002Anomalous behavior of correlation functions of tagged particles are studied in generalizations of the one dimensional asymmetric exclusion problem. In these generalized models the range of the hard-core interactions are changed and the restriction of ... More
Exactly Solvable Interacting Spin-Ice Vertex ModelAug 23 2006A special family of solvable five-vertex model is introduced on a square lattice. In addition to the usual nearest neighbor interactions, the vertices defining the model also interact alongone of the diagonals of the lattice. Such family of models includes ... More
Multi-bump solutions for a class of quasilinear problems involving variable exponentsFeb 27 2014We establish the existence of multi-bump solutions for the following class of quasilinear problems $$ - \Delta_{ p(x) } u + \big( \lambda V(x) + Z(x) \big) u ^{ p(x)-1 } = f(x,u) \text{ in } \mathbb R^N, \, u \ge 0 \text{ in } \mathbb R^N, $$ where the ... More
Nonlinear perturbations of a $p(x)$-Laplacian equation with critical growth in $\mathbb{R}^N$Apr 26 2013Dec 11 2013We prove the existence of solution for a class of $p(x)$-Laplacian equations where the nonlinearity has a critical growth. Here, we consider two cases: the first case involves the situation where the variable exponents are periodic functions. The second ... More
Aggregation in a mixture of Brownian and ballistic wandering particlesApr 10 2006In this paper, we analyze the scaling properties of a model that has as limiting cases the diffusion-limited aggregation (DLA) and the ballistic aggregation (BA) models. This model allows us to control the radial and angular scaling of the patterns, as ... More
Constraining Logotropic Unified Dark Energy ModelsNov 25 2016A unification of dark matter and dark energy in terms of a logotropic perfect dark fluid has recently been proposed, where deviations with respect to the standard $\Lambda {\rm CDM}$ model are dependent on a single parameter $B$. In this paper we show ... More
Scaling laws in the diffusion limited aggregation of persistent random walkersJul 27 2011We investigate the diffusion limited aggregation of particles executing persistent random walks. The scaling properties of both random walks and large aggregates are presented. The aggregates exhibit a crossover between ballistic and diffusion limited ... More
Quasi-stationary simulations of the directed percolation universality class in d = 3 dimensionsJan 05 2011Jan 07 2011We present quasi-stationary simulations of three-dimensional models with a single absorbing configuration, namely the contact process (CP), the susceptible-infected-susceptible (SIS) model and the contact replication process (CRP). The moment ratios of ... More
Kardar-Parisi-Zhang universality class in 2+1 dimensions: Universal geometry-dependent distributions and finite-time correctionsFeb 15 2013Apr 12 2013The dynamical regimes of models belonging to the Kardar-Parisi-Zhang (KPZ) universality class are investigated in d=2+1 by extensive simulations considering flat and curved geometries. Geometry-dependent universal distributions, different from their Tracy-Widom ... More
Sampling methods for the quasistationary regime of epidemic processes on regular and complex networksMay 31 2016Oct 14 2016A major hurdle in the simulation of the steady state of epidemic processes is that the system will unavoidably visit an absorbing, disease-free state at sufficiently long times due to the finite size of the networks where epidemics evolves. In the present ... More
Epidemic thresholds of the Susceptible-Infected-Susceptible model on networks: A comparison of numerical and theoretical resultsJun 28 2012Oct 16 2012Recent work has shown that different theoretical approaches to the dynamics of the Susceptible-Infected-Susceptible (SIS) model for epidemics lead to qualitatively different estimates for the position of the epidemic threshold in networks. Here we present ... More
Phase transitions with infinitely many absorbing states in complex networksSep 28 2012Feb 08 2013We instigate the properties of the threshold contact process (TCP), a process showing an absorbing-state phase transition with infinitely many absorbing states, on random complex networks. The finite size scaling exponents characterizing the transition ... More
Collective versus hub activation of epidemic phases on networksDec 01 2015Feb 19 2016We consider a general criterion to discern the nature of the threshold in epidemic models on scale-free (SF) networks. Comparing the epidemic lifespan of the nodes with largest degrees with the infection time between them, we propose a general dual scenario, ... More
Continuous and discontinuous absorbing-state phase transitions on Voronoi-Delaunay random latticesSep 17 2015Dec 18 2015We study absorbing-state phase transitions in two-dimensional Voronoi-Delaunay (VD) random lattices with quenched coordination disorder. Quenched randomness usually changes the criticality and destroys discontinuous transitions in low-dimensional nonequilibrium ... More
Effects of a kinetic barrier on limited-mobility interface growth modelsFeb 08 2019The role played by a kinetic barrier originated by out-of-plane step edge diffusion, introduced in [Leal \textit{et al.}, \href{https://doi.org/10.1088/0953-8984/23/29/292201}{J. Phys. Condens. Matter \textbf{23}, 292201 (2011)}], is investigated in the ... More
The Noncommutative U(N) Kalb-Ramond TheoryMar 08 2004We present the noncommutative extention of the U(N) Cremmer-Scherk-Kalb-Ramond theory, displaying its differential form and gauge structures. The Seiberg-Witten map of the model is also constructed up to $0(\theta^2)$.
Large Scale Structure in Bekenstein's theory of relativistic Modified Newtonian DynamicsMay 26 2005Feb 08 2006A relativistic theory of modified gravity has been recently proposed by Bekenstein. The tensor field in Einstein's theory of gravity is replaced by a scalar, a vector, and a tensor field which interact in such a way to give Modified Newtonian Dynamics ... More
Gradient flows of time-dependent functionals in metric spaces and applications for PDEsSep 14 2015We develop a gradient-flow theory for time-dependent functionals defined in abstract metric spaces. Global well-posedness and asymptotic behavior of solutions are provided. Conditions on functionals and metric spaces allow to consider the Wasserstein ... More
Periodic solutions for a 1D-model with nonlocal velocity via mass transportOct 10 2014This paper concerns periodic solutions for a 1D-model with nonlocal velocity given by the periodic Hilbert transform. There is a rich literature showing that this model presents singular behavior of solutions via numerics and mathematical approaches. ... More
Quasi-stationary simulations of the contact process on quenched networksJul 01 2011Nov 17 2011We present high-accuracy quasi-stationary (QS) simulations of the contact process in quenched networks, built using the configuration model with both structural and natural cutoffs. The critical behavior is analyzed in the framework of the anomalous finite ... More
Addendum to "Anomalous scaling and super-roughness in the growth of CdTe polycrystalline films"Jan 10 2011The scaling of the growth of CdTe films on glass substrates was investigated by Mata \textit{et al.} [Phys. Rev. B \textbf{78}, 115305 (2008)]. Part of the analysis consisted of the estimation of the correlation length $\xi$ using the decay in the height-height ... More
Assessing the Basel II Internal Ratings-Based Approach: Empirical Evidence from AustraliaNov 29 2014Jul 08 2016The Basel II internal ratings-based (IRB) approach to capital adequacy for credit risk implements an asymptotic single risk factor (ASRF) model. Measurements from the ASRF model of the prevailing state of Australia's economy and the level of capitalisation ... More
New Insights into Time Series Analysis - I - Correlated observationsJun 16 2015The first step when investigating time varying data is the detection of any reliable changes in star brightness. This step is crucial to decreasing the processing time by reducing the number of sources processed in later, slower steps. Variability indices ... More
Morphology transitions induced by chemotherapy in carcinomas "in situ"Dec 30 2002Recently, we have proposed a nutrient-limited model for the avascular growth of tumors including cell proliferation, motility and death \cite{jr}, that, qualitatively reproduces commonly observed morphologies for carcinomas {\it in situ}. In the present ... More
Proximal point method for a special class of nonconvex multiobjective optimization functionsApr 02 2015Feb 17 2017The proximal point method for a special class of nonconvex multiobjective functions is studied in this paper. We show that the method is well defined and that the accumulation points of any generated sequence, if any, are Pareto--Clarke critical points. ... More
Mode solutions for a Klein-Gordon field in anti-de Sitter spacetime with dynamical boundary conditions of Wentzell typeFeb 01 2018Apr 26 2018We study a real, massive Klein-Gordon field in the Poincar\'e fundamental domain of the $(d+1)$-dimensional anti-de Sitter (AdS) spacetime, subject to a particular choice of dynamical boundary conditions of generalized Wentzell type, whereby the boundary ... More
Superradiant instabilities in the Kerr-mirror and Kerr-AdS black holes with Robin boundary conditionsDec 09 2017Feb 01 2018It has been recently observed that a scalar field with Robin boundary conditions (RBCs) can trigger both a superradiant and a bulk instability for a BTZ black hole (BH). To understand the generality and scrutinize the origin of this behavior, we consider ... More
New Insights into Time Series Analysis II - No Correlated ObservationsNov 23 2016Statistical parameters are used in finance, weather, industrial, science, among other vast number of different fields to draw conclusions. They are also used to identify variability patterns on photometric data in order to select non-stochastic variations, ... More
Cardinality of the Ellis semigroup on compact metric countable spacesNov 24 2016Let $E(X,f)$ be the Ellis semigroup of a dynamical system $(X,f)$ where $X$ is a compact metric space. We analyze the cardinality of $E(X,f)$ for a compact countable metric space $X$. A characterization when $E(X,f)$ and $E(X,f)^* = E(X,f) \setminus \{ ... More
On the non-homogeneous Navier-Stokes system with Navier friction boundary conditionsOct 04 2012We address the issue of existence of weak solutions for the non-homogeneous Navier-Stokes system with Navier friction boundary conditions allowing the presence of vacuum zones and assuming rough conditions on the data. We also study the convergence, as ... More
An Existence Result for the Generalized Vector Equilibrium Problem on Hadamard ManifoldJun 19 2014Jun 28 2014A sufficient condition for the existence of a solution for generalized vector equilibrium problem (GVEP) on Hadamard manifold, by using a version of KKM lemma on this context, is presented in this paper. It is worth to point out that, in particular, existence ... More
A reaction-diffusion model for the growth of avascular tumorSep 25 2001Nov 20 2001A nutrient-limited model for avascular cancer growth including cell proliferation, motility and death is presented. The model qualitatively reproduces commonly observed morphologies for primary tumors, and the simulated patterns are characterized by its ... More
Stationary scalar clouds around a BTZ black holeJul 25 2017We establish the existence of stationary clouds of massive test scalar fields around BTZ black holes. These clouds are zero-modes of the superradiant instability and are possible when Robin boundary conditions (RBCs) are considered at the AdS boundary. ... More
Stability and contagion measures for spatial extreme value analysesJun 06 2012As part of global climate change an accelerated hydrologic cycle (including an increase in heavy precipitation) is anticipated. So, it is of great importance to be able to quantify high-impact hydrologic relationships, for example, the impact that an ... More
Existentially Closed Brouwerian SemilatticesFeb 27 2017Jul 25 2017The variety of Brouwerian semilattices is amalgamable and locally finite, hence by well-known results due to W. H. Wheeler, it has a model completion (whose models are the existentially closed structures). In this paper, we supply for such a model completion ... More
Mean-field avalanches in jammed spheresAug 03 2016Aug 24 2016Disordered systems are characterized by the existence of many sample- dependent local energy minima, that cause a stepwise response when the system is perturbed. In this article we use an approach based on elementary probabilistic methods to compute the ... More
Finite-size critical fluctuations in microscopic models of mode-coupling theoryOct 22 2012Jun 12 2013Facilitated spin models on random graphs provide an ideal microscopic realization of the mode-coupling theory of supercooled liquids: they undergo a purely dynamic glass transition with no thermodynamic singularity. In this paper we study the fluctuations ... More
Verifying Patterns of Dynamic Architectures using Model CheckingMar 21 2017Architecture patterns capture architectural design experience and provide abstract solutions to recurring architectural design problems. They consist of a description of component types and restrict component connection and activation. Therefore, they ... More
Nonlinear looped band structure of Bose-Einstein condensates in an optical latticeMay 10 2016We study experimentally the stability of excited, interacting states of bosons in a double-well optical lattice in regimes where the nonlinear interactions are expected to induce "swallowtail" looped band structure. By carefully preparing different initial ... More
Effects of the mean free path and relaxation in a model for the aggregation of particles in superfluid mediaJan 05 2011In this paper, we study a two-dimensional model for the growth of molecular clusters in superfluid helium at low temperature. In the model, particles of diameter a follow random ballistic moves of length \delta = a-256a. Upon attachment on the cluster ... More
A Global Energetic Model for Microquasars (GEMM): A rich and consistent disk+jet solutionOct 01 2008Based on a dynamical model describing how stationary, powerful and self-collimated jets are being launched from a magnetized disk, we build a consistent disk+jet microquasar picture. Our disk is a new type of disk solution called the Jet Emitting Disk ... More
Fighting cancer with virusSep 09 2003One of the most promising strategies to treat cancer is attacking it with viruses. Virus can kill tumor cells specifically or act as carriers that deliver normal genes into cancer cells. A model for virus therapy of cancer is investigated and some of ... More
Self-similar solutions for active scalar equations in Fourier-Besov-Morrey spacesSep 20 2013Feb 13 2014We are concerned with a family of dissipative active scalar equation with velocity fields coupled via multiplier operators that can be of high-order. We consider sub-critical values for the fractional diffusion and prove global well-posedness of solutions ... More
On nonlinear Schrödinger equations with random potentials: existence and probabilistic propertiesApr 09 2013In this paper we are concerned with nonlinear Schr\"odinger equations with random potentials. Our class includes continuum and discrete potentials. Conditions on the potential $V_{\omega}$ are found for existence of solutions almost sure $\omega $. We ... More
Iteration-complexity of gradient, subgradient and proximal point methods on Riemannian manifoldsSep 15 2016This paper considers optimization problems on Riemannian manifolds and analyzes iteration-complexity for gradient and subgradient methods on manifolds with non-negative curvature. By using tools from the Riemannian convex analysis and exploring directly ... More
Universal fluctuations in radial growth models belonging to the KPZ universality classSep 22 2011We investigate the radius distributions (RD) of surfaces obtained with large-scale simulations of radial clusters that belong to the KPZ universality class. For all investigated models, the RDs are given by the Tracy-Widom distribution of the Gaussian ... More
Improving the Redundancy of the Knuth Balancing Scheme for Packet Transmission SystemsNov 09 2017Nov 15 2017A simple scheme was proposed by Knuth to generate balanced codewords from a random binary in- formation sequence. However, this method presents a redundancy which is twice that of the full sets of bal- anced codewords, that is the minimal achievable redun- ... More
The Mathematics and Physics of Diderot. I. On Pendulums and Air ResistanceSep 26 2014In this article Denis Diderot's Fifth Memoir of 1748 on the problem of a pendulum damped by air resistance is discussed. Diderot wrote the Memoir in order to clarify an assumption Newton made without further justification in the first pages of the Principia ... More
An efficient reconciliation algorithm for social networksJul 05 2013Nov 20 2013People today typically use multiple online social networks (Facebook, Twitter, Google+, LinkedIn, etc.). Each online network represents a subset of their "real" ego-networks. An interesting and challenging problem is to reconcile these online networks, ... More
An optimal transport approach for solving dynamic inverse problems in spaces of measuresJan 29 2019In this paper we propose and study a novel optimal transport based regularization of linear dynamic inverse problems. The considered inverse problems aim at recovering a measure valued curve and are dynamic in the sense that (i) the measured data takes ... More