Results for "Jorge Goncalves"

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An Approach to Sparse Continuous-time System Identification from Unevenly Sampled DataFeb 28 2018In this work, we address the problem of identifying sparse continuous-time dynamical systems when the spacing between successive samples (the sampling period) is not constant over time. The proposed approach combines the leave-one-sample-out cross-validation ... More
Linear system identification from ensemble snapshot observationsMar 15 2019Developments in transcriptomics techniques have caused a large demand in tailored computational methods for modelling gene expression dynamics from experimental data. Recently, so-called single-cell experiments have revolutionised genetic studies. These ... More
Koopman-based lifting techniques for nonlinear systems identificationSep 06 2017Apr 24 2019We develop a novel lifting technique for nonlinear system identification based on the framework of the Koopman operator. The key idea is to identify the linear (infinitedimensional) Koopman operator in the lifted space of observables, instead of identifying ... More
Koopman-based lifting techniques for nonlinear systems identificationSep 06 2017Nov 21 2018We develop a novel lifting technique for nonlinear system identification based on the framework of the Koopman operator. The key idea is to identify the linear (infinitedimensional) Koopman operator in the lifted space of observables, instead of identifying ... More
Linear identification of nonlinear systems: A lifting technique based on the Koopman operatorMay 14 2016Aug 27 2016We exploit the key idea that nonlinear system identification is equivalent to linear identification of the socalled Koopman operator. Instead of considering nonlinear system identification in the state space, we obtain a novel linear identification technique ... More
Dynamical Structure Functions for the Estimation of LTI Networks with Limited InformationOct 03 2006This research explores the role and representation of network structure for LTI Systems. We demonstrate that transfer functions contain no structural information without more assumptions being made about the system, assumptions that we believe are unreasonable ... More
Bayesian variable selection in linear dynamical systemsFeb 15 2018We develop a method for reconstructing regulatory interconnection networks between variables evolving according to a linear dynamical system. The work is motivated by the problem of gene regulatory network inference, that is, finding causal effects between ... More
Network Reconstruction from Intrinsic NoiseOct 01 2013Dec 19 2014This paper considers the problem of inferring an unknown network of dynamical systems driven by unknown, intrinsic, noise inputs. Equivalently we seek to identify direct causal dependencies among manifest variables only from observations of these variables. ... More
Dynamic controllers for column synchronization of rotation matrices: a QR-factorization approachAug 11 2017Jan 08 2018In the multi-agent systems setting, this paper addresses continuous-time distributed synchronization of columns of rotation matrices. More precisely, k specific columns shall be synchronized and only the corresponding k columns of the relative rotations ... More
Towards Almost Global Synchronization on the Stiefel ManifoldMar 14 2018Jul 25 2018A graph $\mathcal{G}$ is referred to as $\mathsf{S}^1$-synchronizing if, roughly speaking, the Kuramoto-like model whose interaction topology is given by $\mathcal{G}$ synchronizes almost globally. The Kuramoto model evolves on the unit circle, \ie the ... More
Intrinsic almost global consensus on the n-sphereSep 16 2016Oct 06 2016This paper provides a novel analysis of the global convergence properties of a large class of consensus protocols for multi-agent systems that evolve in continuous time on the n-sphere. The feedback laws are intrinsic in the sense of not rely on a protocol ... More
A Full Bayesian Approach to Sparse Network Inference using Heterogeneous DatasetsJan 04 2019Network inference has been attracting increasing attention in several fields, notably systems biology, control engineering and biomedicine. To develop a therapy, it is essential to understand the connectivity of biochemical units and the internal working ... More
High Precision Variational Bayesian Inference of Sparse Linear NetworksJan 03 2019Sparse networks can be found in a wide range of applications, such as biological and communication networks. Inference of such networks from data has been receiving considerable attention lately, mainly driven by the need to understand and control internal ... More
High-dimensional Kuramoto models on Stiefel manifolds synchronize complex networks almost globallyJul 26 2018Jan 22 2019The Kuramoto model of a system of coupled phase oscillators describe synchronization phenomena in nature. We propose a generalization of the Kuramoto model where each oscillator state lives on the compact, real Stiefel manifold St(p,n). Previous work ... More
Correlating Pedestrian Flows and Search Engine QueriesJun 19 2012An important challenge for ubiquitous computing is the development of techniques that can characterize a location vis-a-vis the richness and diversity of urban settings. In this paper we report our work on correlating urban pedestrian flows with Google ... More
Inverse Problems for Matrix Exponential in System Identification: System AliasingMay 23 2016This note addresses identification of the $A$-matrix in continuous time linear dynamical systems on state-space form. If this matrix is partially known or known to have a sparse structure, such knowledge can be used to simplify the identification. We ... More
On Transitive Consistency for Linear Invertible Transformations between Euclidean Coordinate SystemsSep 02 2015Transitive consistency is an intrinsic property for collections of linear invertible transformations between Euclidean coordinate frames. In practice, when the transformations are estimated from data, this property is lacking. This work addresses the ... More
The problem of almost global consensus on the n-sphereSep 16 2016This paper provides a novel analysis of the global convergence properties of a large class of consensus protocol for multi-agent systems that evolve in continuous time on the n-sphere. It is shown that, for any connected undirected graph topology and ... More
Shaping Pulses to Control Bistable Monotone Systems Using Koopman OperatorMay 20 2016In this paper, we further develop a recently proposed control method to switch a bistable system between its steady states using temporal pulses. The motivation for using pulses comes from biomedical and biological applications (e.g. synthetic biology), ... More
Distributed methods for synchronization of orthogonal matrices over graphsJan 25 2017Apr 07 2017This paper addresses the problem of synchronizing orthogonal matrices over directed graphs. For synchronized transformations (or matrices), composite transformations over loops equal the identity. We formulate the synchronization problem as a least-squares ... More
Almost global consensus on the n-sphereSep 16 2016Sep 12 2017This paper establishes novel results regarding the global convergence properties of a large class of consensus protocols for multi-agent systems that evolve in continuous time on the n-dimensional unit sphere or n-sphere. For any connected, undirected ... More
Situationally-Induced Impairments and Disabilities ResearchApr 12 2019Research has shown that various environmental factors impact smartphone interaction and lead to Situationally-Induced Impairments and Disabilities. In this work we discuss the importance of thoroughly understanding the effects of these situational impairments ... More
Consensus and Formation Control on SE(3) for Switching TopologiesNov 01 2015This paper addresses the consensus problem and the formation problem on SE(3) in multi-agent systems with directed and switching interconnection topologies. Several control laws are introduced for the consensus problem. By a simple transformation, it ... More
Minimal realization of the dynamical structure function and its application to network reconstructionSep 17 2012Network reconstruction, i.e., obtaining network structure from data, is a central theme in systems biology, economics and engineering. In some previous work, we introduced dynamical structure functions as a tool for posing and solving the problem of network ... More
Synchronisation of Partial Multi-Matchings via Non-negative FactorisationsMar 16 2018Mar 25 2019In this work we study permutation synchronisation for the challenging case of partial permutations, which plays an important role for the problem of matching multiple objects (e.g. images or shapes). The term synchronisation refers to the property that ... More
Linear Dynamic Network Reconstruction from Heterogeneous DatasetsDec 06 2016This paper addresses reconstruction of linear dynamic networks from heterogeneous datasets. Those datasets consist of measurements from linear dynamical systems in multiple experiment subjected to different experimental conditions, e.g., changes/perturbations ... More
Synchronisation of Partial Multi-Matchings via Non-negative FactorisationsMar 16 2018Jul 12 2018In this work we study permutation synchronisation for the challenging case of partial permutations, which plays an important role for the problem of matching multiple objects (e.g. images or shapes). The term synchronisation refers to the property that ... More
Experimental design trade-offs for gene regulatory network inference: an in silico study of the yeast Saccharomyces cerevisiae cell cycleDec 14 2017Time-series of high throughput gene sequencing data intended for gene regulatory network (GRN) inference are often short due to the high costs of sampling cell systems. Moreover, experimentalists lack a set of quantitative guidelines that prescribe the ... More
A state-space approach to sparse dynamic network reconstructionNov 21 2018Dynamic network reconstruction has been shown to be challenging due to the requirements on sparse network structures and network identifiability. The direct parametric method (e.g., using ARX models) requires a large amount of parameters in model selection. ... More
A Lifting method for analyzing distributed synchronization on the unit sphereMay 07 2018Jun 07 2018This paper introduces a new lifting method for analyzing convergence of continuous-time distributed synchronization/consensus systems on the unit sphere. Points on the d-dimensional unit sphere are lifted to the (d+1)-dimensional Euclidean space. The ... More
Dynamic Network Reconstruction from Heterogeneous DatasetsDec 06 2016Feb 04 2019Performing multiple experiments is common when learning internal mechanisms of complex systems. These experiments can include perturbations to parameters or external disturbances. A challenging problem is to efficiently incorporate all collected data ... More
Linear Shape Deformation Models with Local Support Using Graph-based Structured Matrix FactorisationOct 28 2015May 11 2016Representing 3D shape deformations by linear models in high-dimensional space has many applications in computer vision and medical imaging, such as shape-based interpolation or segmentation. Commonly, using Principal Components Analysis a low-dimensional ... More
Identification of Sparse Continuous-Time Linear Systems with Low Sampling Rate: Optimization ApproachesMay 30 2016Jun 07 2016This paper addresses identification of sparse linear and noise-driven continuous-time state-space systems, i.e., the right-hand sides in the dynamical equations depend only on a subset of the states. The key assumption in this study, is that the sample ... More
Identification of Sparse Continuous-Time Linear Systems with Low Sampling Rate: Exploring Matrix LogarithmsMay 27 2016May 30 2016A continuous time linear dynamic in state space form has an $A$-matrix that reveals the connection between the states. Many dynamical systems allow a a sparse structure for this matrix. This means that the right-hand sides of the dynamical equations depend ... More
Continuous time Gaussian process dynamical models in gene regulatory network inferenceAug 24 2018One of the focus areas of modern scientific research is to reveal mysteries related to genes and their interactions. The dynamic interactions between genes can be encoded into a gene regulatory network (GRN), which can be used to gain understanding on ... More
Compressed Sensing for Network ReconstructionNov 15 2014The problem of identifying sparse solutions for the link structure and dynamics of an unknown linear, time-invariant network is posed as finding sparse solutions x to Ax=b. If the sensing matrix A satisfies a rank condition, this problem has a unique, ... More
Identification of Sparse Continuous-Time Linear Systems with Low Sampling Rate: Optimization ApproachesMay 30 2016Apr 17 2018This paper addresses identification of sparse linear and noise-driven continuous-time state-space systems, i.e., the right-hand sides in the dynamical equations depend only on a subset of the states. The key assumption in this study, is that the sample ... More
Systems Aliasing in Dynamic Network Reconstruction: Issues on Low Sampling FrequenciesMay 27 2016Oct 29 2018Network reconstruction of dynamical continuous-time (CT) systems is motivated by applications in many fields. Due to experimental limitations, especially in biology, data could be sampled at low frequencies, leading to significant challenges in network ... More
A multifactorial evaluation framework for gene regulatory network reconstructionJun 28 2019In the past years, many computational methods have been developed to infer the structure of gene regulatory networks from time-series data. However, the applicability and accuracy presumptions of such algorithms remain unclear due to experimental heterogeneity. ... More
Scaling limits for gradient systems in random environmentFeb 17 2007For interacting particle systems that satisfies the gradient condition, the hydrodynamic limit and the equilibrium fluctuations are well known. We prove that under the presence of a symmetric random environment, these scaling limits also hold for almost ... More
No-horizon theorem for spacetimes with spacelike G1 isometry groupsDec 30 2003We consider four-dimensional spacetimes $(M,{\mathbf g})$ which obey the Einstein equations ${\mathbf G}={\mathbf T}$, and admit a global spacelike $G_{1}={\mathbb R}$ isometry group. By means of dimensional reduction and local analyis on the reduced ... More
Shear-free gravitational collapse is strongly censoredDec 30 2003We consider spherically symmetric spacetimes with matter whose timelike flow is assumed to be shear-free. A number of results on the formation and visibility of spacetime singularities is proven, with the main one being that shear-free collapse cannot ... More
Naked singularities in Tolman-Bondi-de Sitter collapseDec 07 2000We study the formation of central naked singularities in spherical dust collapse with a cosmological constant. We find that the central curvature singularity is locally naked, Tipler strong, and generic, in the sense that it forms from a non-zero-measure ... More
Black hole formation from massive scalar field collapse in the Einstein-de Sitter universeAug 15 2000We study the spherically symmetric collapse of a real, minimally coupled, massive scalar field in an asymptotically Einstein-de Sitter spacetime background. By means of an eikonal approximation for the field and metric functions, we obtain a simple analytical ... More
Constraining the Strength and CP Structure of Dark Production at the LHC: the Associated Top-Pair ChannelNov 19 2015We consider the production of dark matter in association with a pair of top quarks, mediated by a scalar or pseudoscalar particle in a generic Simplified Model. We demonstrate that the difference of azimuthal angle between the two leptons $\Delta \phi_{ll}$, ... More
Solution to the Hidden Subgroup Problem for a Class of Noncommutative GroupsApr 07 2011The hidden subgroup problem (HSP) plays an important role in quantum computation, because many quantum algorithms that are exponentially faster than classical algorithms can be casted in the HSP structure. In this paper, we present a new polynomial-time ... More
Epidemics scenarios in the "Romantic network"Aug 09 2012The structure of sexual contacts, its contacts network and its temporal interactions, play an important role in the spread of sexually transmitted infections. Unfortunately, that kind of data is very hard to obtain. One of the few exceptions is the "Romantic ... More
Anyons in 1+1 DimensionsMar 20 1995The possibility of excitations with fractional spin and statististics in $1+1$ dimensions is explored. The configuration space of a two-particle system is the half-line. This makes the Hamiltonian self-adjoint for a family of boundary conditions parametrized ... More
Distributed Kalman filtering with minimum-time consensus algorithmMar 16 2017Fueled by applications in sensor networks, these years have witnessed a surge of interest in distributed estimation and filtering. A new approach is hereby proposed for the Distributed Kalman Filter (DKF) by integrating a local covariance computation ... More
Identifying Biochemical Reaction Networks From Heterogeneous DatasetsSep 17 2015Sep 18 2015In this paper, we propose a new method to identify biochemical reaction networks (i.e. both reactions and kinetic parameters) from heterogeneous datasets. Such datasets can contain (a) data from several replicates of an experiment performed on a biological ... More
A Solution for Multi-Alignment by Transformation SynchronisationOct 30 2014Apr 14 2015The alignment of a set of objects by means of transformations plays an important role in computer vision. Whilst the case for only two objects can be solved globally, when multiple objects are considered usually iterative methods are used. In practice ... More
Matters of Gravity, the newsletter of the APS TG on gravitationFeb 09 1998Contents: *News: Topical group news, by Jim Isenberg April 1997 Joint APS/AAPT Meeting, GTG program, by Abhay Ashtekar Formation of the Gravitational-Wave International Committee, by Sam Finn The 1997 Xanthopoulos award, by Abhay Asthekar We hear that..., ... More
The Heavy Quark Free Energy in QCD and in Gauge Theories with Gravity DualsMar 03 2010Mar 19 2010We show that the Polyakov loop approaches its asymptotic value at high temperatures {\it from below} in any strongly-coupled gauge theory at large $N_c$ with a dual supergravity description. In these theories the Polyakov loop can be used to define a ... More
Connecting Polyakov Loops to the Thermodynamics of $SU(N_c)$ Gauge Theories Using the Gauge-String DualityOct 07 2009Mar 04 2010We show that in four-dimensional gauge theories dual to five-dimensional Einstein gravity coupled to a single scalar field in the bulk the derivative of the single heavy quark free energy in the deconfined phase is $dF_{Q}(T)/dT \sim -1/c_s^2(T)$, where ... More
Dense granular media as athermal glassesOct 16 2001I briefly describe how mean-field glass models can be extended to the case in which the bath and friction are non-thermal, thus promoting them to granular matter mean-field caricatures. Solving their dynamics one discovers a temperature with a thermodynamic ... More
(Super)-Gravities Beyond 4 DimensionsJun 18 2002Dec 04 2002These lectures are intended as a broad introduction to Chern Simons gravity and supergravity. The motivation for these theories lies in the desire to have a gauge invariant action -in the sense of fiber bundles- in more than three dimensions, which could ... More
Convergence of homogeneous manifoldsMay 11 2011Mar 02 2012We study in this paper three natural notions of convergence of homogeneous manifolds, namely infinitesimal, local and pointed, and their relationship with a fourth one, which only takes into account the underlying algebraic structure of the homogeneous ... More
On the moment map for the variety of Lie algebrasJun 05 2002Let V be the vector space of all skew-symmetric (non-associative) complex algebras of dimension n and L the algebraic subset of V of all Lie algebras. We consider the moment map for the action of GL(n) on the projective space P(V) and study the critical ... More
Spontaneous breaking of axial symmetry for Schroedinger's equation in the presence of a magnetic fieldSep 21 2000For appropriate parameters, the ground state for the Schroedinger and Ampere coupled equations in a cylindric domain does not have axial symmetry.
Flux-induced Nernst effect in a superconducting loopSep 03 2013Aug 26 2014When a superconducting ring encloses a magnetic flux that is not an integer multiple of half the quantum of flux, a voltage arises in the direction perpendicular to the temperature gradient. This effect is entirely due to thermal fluctuations. We study ... More
Confinement into a state with persistent current by thermal quenching of loop of Josephson junctionsApr 04 2007We study a loop of Josephson junctions that is quenched through its critical temperature. For three or more junctions, symmetry breaking states can be achieved without thermal activation, in spite of the fact that the relaxation time is practically constant ... More
A probability theory for non-equilibrium gravitational systemsJun 01 2015This paper uses dynamical invariants to describe the evolution of collisionless systems subject to time-dependent gravitational forces without resorting to maximum-entropy probabilities. We show that collisionless relaxation can be viewed as a special ... More
Approaches of near stars to the SunSep 05 2014We investigate aspects of computing the perihelion distances and impact parameters for near stars to the Sun, and, we analyze the solar motion. Keywords: perihelion distance, impact parameter, Oort cloud, solar motion
Reconstruction and stability for piecewise smooth potentials in the planeJun 09 2016Jul 15 2016We show that potentials with jump discontinuities can be recovered from the Dirichlet-to-Neumann map using Bukhgeim's method. Combining with known formulas, this enables the recovery from the scattering amplitude at a fixed energy. We also provide a priori ... More
Mass ratio determination from Halpha lines in Black-Hole X-ray transientsMar 29 2016May 10 2016We find that the mass ratio q in quiescent black hole (BH) X-ray transients is tightly correlated with the ratio of the double peak separation (DP) to the full-width-half maximum (FWHM) of the Halpha emission line, log q = -6.88 -23.2 log (DP/FWHM). The ... More
Laplacian flow of homogeneous G2-structures and its solitonsFeb 26 2016Nov 15 2016We use the bracket flow/algebraic soliton approach to study the Laplacian flow of $G_2$-structures and its solitons in the homogeneous case. We prove that any homogeneous Laplacian soliton is equivalent to a semi-algebraic soliton (i.e.\ a $G$-invariant ... More
General Navier-Stokes-like Momentum and Mass-Energy EquationsOct 22 2014Aug 29 2016A new system of general Navier-Stokes-like equations is proposed to model electromagnetic analogous to hydrodynamic. While most attempts to derive analogues of hydrodynamic to electromagnetic, and vice-versa, start with Navier-Stokes or a Euler approximation, ... More
Quantum bound to chaos and the semiclassical limitDec 05 2016We discuss the quantum bound on chaos in the context of the free propagation of a particle in an arbitrarily curved surface at low temperatures. The semiclassical calculation of the Lyapunov exponent can be performed in much the same way as the corresponding ... More
Mn I hyperfine structure in the near-infraredJun 10 1999Hyperfine interaction constants and hyperfine components of MnI lines in the near-infrared J and H bands were obtained by fitting the solar spectrum. I identified the 17744-A solar absorption line as resulting from MnI and I discarded the identifications ... More
On unitary representability of topological groupsJul 07 2006Jul 10 2006We prove that the additive group $(E^\ast,\tau_k(E))$ of an $\mathscr{L}_\infty$-Banach space $E$, with the topology $\tau_k(E)$ of uniform convergence on compact subsets of $E$, is topologically isomorphic to a subgroup of the unitary group of some Hilbert ... More
Propagators from characteristic surfacesJan 17 2005We study the Goursat or characteristic problem, i.e. a hyperbolic equation with given data on a surface (the half of the standard Cauchy problem), with some kind of dimensional regularization procedure to deal with the divergences that appear. We will ... More
$p$-adic derived formal geometry and derived Raynaud localization TheoremMay 08 2018The goal of the present text is to give a proof of an analogue of Raynaud localization theorem in the setting of derived geometry. More explicitly, we show that the \infcat of (good) derived $k$-analytic spaces can be realized as a localization of the ... More
Scalar perturbations and the possible self-destruction of the phantom menaceMar 07 2006Some analysis of the supernovae type Ia observational data seems to indicate that the Universe today is dominated by a phantom field, for which all energy conditions are violated. Such phantom field may imply a singularity in a future finite time, called ... More
Ab initio study of proper topological ferroelectricity in layered perovskite La2Ti2O7Jan 11 2011We present a first-principles investigation of ferroelectricity in layered perovskite oxide La2Ti2O7 (LTO), one of the compounds with highest Curie temperature known (1770 K). Our calculations reveal that LTO's ferroelectric transition results from the ... More
Does magnetic pressure affect the ICM dynamics?Jun 28 1999Jul 08 1999A possible discrepancy found in the determination of mass from gravitational lensing data, and from X-rays observations, has been largely discussed in the latest years (for instance, Miralda-Escude & Babul (1995)). Another important discrepancy related ... More
Extragalactic Planetary Nebulae: tracers of the chemical evolution of nearby galaxiesOct 06 2011Jan 10 2012The study of the chemical composition of Planetary Nebulae in external galaxies is of paramount importance in the fields of stellar evolution and of the chemical enrichment history of galaxies. In the last years a number of spectroscopic studies with ... More
A Socio-Technical approach to address the Information security: Using the 27001 Manager ArtefactSep 25 2015In general, the perspective customer / supplier followed by organizations, regarding information security management, is based mainly on management controls based on standards such as ISO / IEC 27001: 2015, resulting in the production of especially technical ... More
Pseudoclassical description of the massive Dirac particles in odd dimensionsMar 08 1996A pseudoclassical model is proposed to describe massive Dirac (spin one-half) particles in arbitrary odd dimensions. The quantization of the model reproduces the minimal quantum theory of spinning particles in such dimensions. A dimensional duality between ... More
On Moving Frames and Noether's Conservation LawsJun 23 2010Mar 23 2011Noether's Theorem yields conservation laws for a Lagrangian with a variational symmetry group. The explicit formulae for the laws are well known and the symmetry group is known to act on the linear space generated by the conservation laws. The aim of ... More
Scalar Simplified Models for Dark MatterOct 23 2014Dec 21 2014We introduce a set of minimal simplified models for dark matter interactions with the Standard Model, connecting the two sectors via either a scalar or pseudoscalar particle. These models have a wider regime of validity for dark matter searches at the ... More
Chern-Simons Forms in Gravitation TheoriesAug 16 2012The Chern-Simons (CS) form evolved from an obstruction in mathematics into an important object in theoretical physics. In fact, the presence of CS terms in physics is more common than one may think: they seem to play an important role in high Tc superconductivity ... More
Ricci flow of homogeneous manifoldsDec 26 2011Mar 02 2012We present in this paper a general approach to study the Ricci flow on homogeneous manifolds. Our main tool is a dynamical system defined on a subset H(q,n) of the variety of (q+n)-dimensional Lie algebras, parameterizing the space of all simply connected ... More
Ricci soliton solvmanifoldsFeb 02 2010All known examples of nontrivial homogeneous Ricci solitons are left-invariant metrics on simply connected solvable Lie groups whose Ricci operator is a multiple of the identity modulo derivations (called solsolitons, and nilsolitons in the nilpotent ... More
A canonical compatible metric for geometric structures on nilmanifoldsOct 27 2004Let (N,g) be a nilpotent Lie group endowed with an invariant geometric structure (cf. symplectic, complex, hypercomplex or any of their `almost' versions). We define a left invariant Riemannian metric on N compatible with g to be minimal, if it minimizes ... More
Spontaneous superconducting islands and Hall voltage in clean superconductorsSep 10 2004Oct 27 2004We study a clean superconductor in the Hall configuration, in the framework of a purely dissipative time-dependent Ginzburg--Landau theory. We find situations in which the order parameter differs significantly from zero in a set of islands that appear ... More
A Formal Model for Dynamically Adaptable ServicesNov 11 2010The growing complexity of software systems as well as changing conditions in their operating environment demand systems that are more flexible, adaptive and dependable. The service-oriented computing paradigm is in widespread use to support such adaptive ... More
The last sunset on mainland EuropeAug 09 2014This paper documents the places in mainland Europe at which the sun sets latest, by Coordinated Universal Time (UTC), on any given day (distortion due to differences in local standard times is ignored). In contradiction to the na\"ive assumption that ... More
On the extended loop calculusDec 05 1995Some features of extended loops are considered. In particular, the behaviour under diffeomorphism transformations of the wavefunctions with support on the extended loop space are studied. The basis of a method to obtain analytical expressions of diffeomorphism ... More
$K \rightarrow π\ell^+ \ell^-$: Status and updateNov 22 2016$K \rightarrow \pi \ell^+ \ell^-$ decays, $\ell = e, \mu$, will be one of the goals of future kaon facilities, like NA62 (CERN) and K$^0$TO (J-PARC). We review briefly the theoretical status of those processes.
Moduli of $\ell$-adic representations of a profinite groupSep 13 2017May 29 2018The purpose of the current text is twofold. First, given any profinite group topologically of finite generation, $G$, we construct the moduli stack parametrizing rank $n$ continuous $\mathbb{Q}_\ell$-representations of $G$, where $\ell$ not necessarily ... More
Fluctuations of the gravitational field generated by a random population of extended substructuresOct 17 2017Dec 04 2017A large population of extended substructures generates a stochastic gravitational field that is fully specified by the function $p({\bf F})$, which defines the probability that a tracer particle experiences a force $\bf F$ within the interval ${\bf F},{\bf ... More
Canonical metrics of commuting mapsMar 24 2008In the present work we establish the equality of the canonical metric of two commuting maps on an algebraic variety X. As a consequence the canonical height and measure associated to both maps are identical.
Historical Comments on Monge's Ellipsoid and the Configuration of Lines of Curvature on Surfaces Immersed in ${\mathbb R}^3$Nov 18 2004This is an essay on the historical landmarks leading to the study of principal configurations on surfaces, their structural stability and further generalizations. Here it is pointed out that in the work of Monge, 1796, are found elements of the qualitative ... More
Explicit reciprocity for higher local fieldsMay 30 2017Aug 28 2018Using the previously constructed explicit reciprocity laws for the generalized Kummer pairing of an arbitrary (one-dimensional) formal group, in this article a special consideration is given to Lubin-Tate formal groups. In particular, this allows for ... More
The Mass Spectrum of X-Ray BinariesMar 03 2005This review summarizes the observational constraints on the mass spectrum of compact objects in X-ray binaries. We currently have 20 X-ray binaries with confirmed black holes, based on dynamical information (i.e. mass in excess of 3 Msun). In two cases, ... More
A Quantum Fluctuation TheoremJul 24 2000Aug 16 2001We consider a quantum system strongly driven by forces that are periodic in time. The theorem concerns the probability $P(e)$ of observing a given energy change $e$ after a number of cycles. If the system is thermostated by a (quantum) thermal bath, $e$ ... More
Rheology, and how to stop agingDec 21 1998Recent analytical developments in glass theory are equally relevant to the understanding of anomalous rheology, with characteristic features such as the Reynolds dilatancy and the driving-power dependence of the viscosity arising naturally. A notion of ... More
Characterization of the spontaneous symmetry breaking due to quenching of a one-dimensional superconducting loopJan 05 2013Apr 25 2013We study the final distribution of the winding numbers in a 1D superconducting ring that is quenched through its critical temperature in the absence of magnetic flux. The study is conducted using the stochastic time-dependent Ginzburg--Landau model, and ... More
The Fight Against the Second Law of ThermodynamicsFeb 05 1995Jan 15 1997After presenting possible motives for fighting against the second law of thermodynamics, several attempts to beat this law are analyzed. The second law wins, but an interesting interpretation of it emerges. This interpretation uses the notion of ``encoded ... More
The ADM papers and part of their modern legacy: loop quantum gravityMay 08 2015We present a summary for non-specialists of loop quantum gravity as part of the modern legacy of the series of papers by Arnowitt, Deser and Misner circa 1960.