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ProPublica's COMPAS Data RevisitedJun 11 2019Jul 08 2019I examine the COMPAS recidivism risk score and criminal history data collected by ProPublica in 2016 that fueled intense debate and research in the nascent field of 'algorithmic fairness'. ProPublica's COMPAS data is used in an increasing number of studies ... More

ProPublica's COMPAS Data RevisitedJun 11 2019In this paper I re-examine the COMPAS recidivism score and criminal history data collected by ProPublica in 2016, which has fueled intense debate and research in the nascent field of `algorithmic fairness' or `fair machine learning' over the past three ... More

ProPublica's COMPAS Data RevisitedJun 11 2019Jun 13 2019In this paper I re-examine the COMPAS recidivism score and criminal history data collected by ProPublica in 2016, which has fueled intense debate and research in the nascent field of `algorithmic fairness' or `fair machine learning' over the past three ... More

Speeding Up MCMC by Delayed Acceptance and Data SubsamplingJul 22 2015The complexity of Markov Chain Monte Carlo (MCMC) algorithms arises from the requirement of a likelihood evaluation for the full data set in each iteration. Payne and Mallick (2014) propose to speed up the Metropolis-Hastings algorithm by a delayed acceptance ... More

Exchange rings and real rank zero C*-algebras associated with finitely separated graphsMay 12 2017We introduce a generalisation of Condition (K) to finitely separated graphs and show that it is equivalent to essential freeness of the associated partial action as well as the exchange property of any of the associated tame algebras. As a consequence, ... More

On Nichols algebras of low dimensionApr 10 2000This is a contribution to the classification program of pointed Hopf algebras. We give a generalization of the quantum Serre relations and propose a generalization of the Frobenius-Lusztig kernels in order to compute Nichols algebras of diagonal group ... More

Extracting the Bs - anti-Bs mixing angle from B--> VV decays and comments on the puzzling B--> K* l+l- decayJul 16 2008Oct 16 2008Three different strategies to extract the weak mixing phase phi_s of the Bs system using B--> VV decays (Bs--> K* anti-K*, Bs--> phi anti-K* and Bs--> phi phi) are discussed. Those penguin-mediated decays are computed in the framework of a new combined ... More

CKM angles from non-leptonic B decays using SU(3) flavour symmetryNov 04 2003We discuss the determination of the CKM angles gamma and alpha using recent data from non-leptonic B decays together with flavour symmetries. Penguin effects are controlled by means of the CP-averaged branching ratio B_d \to \pi^\pm K^\mp. The information ... More

The Polarization of the Cosmic Microwave BackgroundMay 15 2003May 15 2003We summarize the physical mechanism by which the Cosmic Microwave Background acquires a small degree of polarization. We discuss the imprint left by gravitational waves and the use of polarization as a test of the inflationary paradigm. We discuss some ... More

Searching for fluctuations in the IGM temperature using the Lyman alpha forestFeb 12 2001We propose a statistical method to search for fluctuations in the temperature of the intergalactic medium (IGM) using the Lyman $\alpha$ forest. The power on small scales ($\sim 25 \km/\s$) is used as a thermometer and fluctuations of this power are constrained. ... More

Low-energy neutrino-photon inelastic interactionsMay 18 1999The computation of the polarized amplitudes and cross section of the processes $\gamma\nu\to\gamma\gamma \nu$, $\gamma\gamma \to \gamma\nu\bar\nu$ and $\nu\bar\nu \to \gamma\gamma\gamma$ is described. We used an effective lagrangian approach for energies ... More

Minimizing interference in ad-hoc networks with bounded communication radiusFeb 14 2011Jun 29 2012We consider a topology control problem in which we are given a set of $n$ sensors in the plane and we would like to assign a communication radius to each of them. The radii assignment must generate a strongly connected network and have low receiver-based ... More

Merging Flavour Symmetries with QCD Factorisation for B-->KK DecaysJan 15 2007The interplay between flavour symmetries connecting Bs-->KK decays with the recently measured Bd--> K0 anti-K0 decay and QCD Factorisation opens new strategies to describe the decays Bs--> K0 anti-K0 and Bs--> K+ K- in the SM and in supersymmetry. A new ... More

The Angular Distribution of B0-> K*0(->K-pi+)l+l- at Large Recoil in and Beyond the SMNov 23 2005We discuss, in detail, the K* polarization states in the exclusive B meson decay B0-> K*0(-> K-pi+)l^+l^- (l=e, \mu, \tau) in the low dilepton mass region. We focus on the study of the angular distribution of this decay that provides valuable information ... More

Impact of B physics on model building and vice versa: an exampleSep 27 2002We motivate that the start-up of the B factories has opened a new precision flavour physics era, with an important effect on model building. Using as an example a left-right model with spontaneous CP violation, we will show how the inclusion of the new ... More

On the S-wave pollution of B-> K* l+l- observablesSep 07 2012Sep 14 2012It has been argued recently that transverse asymmetries that are expected to be shielded from the presence of the S-wave (Kpi) pairs originating from the decay of a scalar K0* meson, are indeed affected by this pollution due to the impossibility to extract ... More

Nonparametric geometric outlier detectionNov 13 2018Outlier detection is a major topic in robust statistics due to the high practical significance of anomalous observations. Many existing methods are, however, either parametric or cease to perform well when the data is far from linearly structured. In ... More

The nature of the E-B decomposition of CMB polarizationJun 10 2001We present a derivation of the transformation between the Q and U Stokes parameters and the E and B scalar and pseudo-scalar fields. We emphasize the geometrical properties that such transformation must satisfy. We present the E and B decomposition of ... More

Model independent sum rules for B-> pi K decaysMay 11 2001We provide a set of sum rules relating CP-averaged branching ratios and CP-asymmetries of the $B \to \pi K$ modes. They prove to be useful as a mechanism to `test' experimental data given our expectations of the size of isospin breaking. A set of observables ... More

Lensing of the CMB: Non Gaussian aspectsOct 27 1999Jun 22 2000We study the generation of CMB anisotropies by gravitational lensing on small angular scales. We show these fluctuations are not Gaussian. We prove that the power spectrum of the tail of the CMB anisotropies on small angular scales directly gives the ... More

Polarization of the Microwave Background in Reionized ModelsAug 09 1996Nov 20 1996I discuss the physics of polarization in models with early reionization. For sufficiently high optical depth to recombination the polarization is boosted on large scales while it is suppressed on smaller scales. New peaks appear in the polarization power ... More

On nuclearity and exactness of the tame C*-algebras associated with finitely separated graphsMay 12 2017We introduce a graph theoretic property called Condition (N) for finitely separated graphs and prove that it is equivalent to both nuclearity and exactness of the associated universal tame graph C*-algebra.

Markovian Random Iterations of MapsMay 24 2019In this paper, we study Markovian random iterations of maps on standard measurable spaces. We establish a one-to-one correspondence between stationary measures and a certain class of invariant measures of a Markovian random iteration, extending a similar ... More

Markovian Random Iterations of MapsMay 24 2019May 27 2019In this paper, we study Markovian random iterations of maps on standard measurable spaces. We establish a one-to-one correspondence between stationary measures and a certain class of invariant measures of a Markovian random iteration, extending a similar ... More

CMB Polarization ExperimentsSep 26 1997We discuss the analysis of polarization experiments with particular emphasis on those that measure the Stokes parameters on a ring on the sky. We discuss the ability of these experiments to separate the $E$ and $B$ contributions to the polarization signal. ... More

Modeling catastrophic deaths using EVT with a microsimulation approach to reinsurance pricingOct 31 2013Recently, a marked Poisson process (MPP) model for life catastrophe risk was proposed in [6]. We provide a justification and further support for the model by considering more general Poisson point processes in the context of extreme value theory (EVT), ... More

A perturbation basis for calculating NMR DiffusometryAug 27 2013An approximative method for solving the Bloch-Torrey equation in general porous media is presented. The method expand the boundaries defining the porous media using electrostatic charges. As a result the eigenvalue problem of the Laplace operator in a ... More

Indecomposable racks of order p^2Mar 15 2002We classify indecomposable racks of order p^2 (p a prime). There are 2p^2 - 2p - 2 isomorphism classes, among which 2p^2 - 3p - 1 correspond to quandles. In particular, we prove that an indecomposable quandle of order p^2 is affine (=Alexander). One of ... More

Pointed Hopf algebras of dimension 32Oct 02 2001We give a complete classification of the 32-dimensional pointed Hopf algebras over an algebraically closed field k with characteristic different from 2. It turns out that there are infinite families of isomorphism classes of pointed Hopf algebras of dimension ... More

Markovian Random Iterations of MapsMay 24 2019Jun 05 2019In this paper, we study Markovian random iterations of maps on standard measurable spaces. We establish a one-to-one correspondence between stationary measures and a certain class of invariant measures of a Markovian random iteration, extending a similar ... More

Commutator expansions in NMR diffusometryAug 18 2014In this paper commutator expansions for solving the Bloch-Torrey's equation are derived. An exact solution for free diffusion in a constant magnetic field gradient is found. Furthermore the moments of the signal in the short gradient pulse limit for spins ... More

Two Datasets of Questions and Answers for Studying the Development of Cross-platform Mobile Applications using Xamarin FrameworkDec 27 2017Jul 09 2018A cross-platform mobile application is an application that runs on multiple mobile platforms (Android, iOS). Several frameworks, have been proposed to simplify the development of cross-platform mobile applications and, therefore, to reduce development ... More

Determination of gamma and alpha from non-leptonic B decays with SU(3) flavour symmetryJun 06 2003Jun 30 2003We describe in detail the method we have used to determine the CKM angles gamma, alpha and beta using flavour symmetries between non-leptonic B decays. This method is valid in the context of the SM but also in presence of New Physics not affecting the ... More

A fermiophobic SU(2)xSU(2)xU(1) extension of the Standard ModelMay 21 1997A new type of gauge extension of the SM is proposed. It is based on a SU(2)xSU(2)xU(1) group with the peculiarity that the gauge bosons of the extra SU(2) do not couple to fermions. This feature relaxes some of the constraints on the masses of the new ... More

Complete connections on fiber bundlesDec 11 2015Every fiber bundle admits a complete (Ehresmann) connection. After a first published incorrect proof, this has appeared in several other references, always relying in a more ellaborated argument, that we have found to be incorrect too. We present here ... More

Random products of maps synchronizing on averageFeb 06 2018Feb 09 2018We present a necessary and sufficient condition for a random product of maps on a compact metric space to be (strongly) synchronizing on average.

Quantum effects in the scattering by the magnetic field of a solenoidFeb 07 2002We present a relativistic quantum calculation at first order in perturbation theory of the differential cross section for a Dirac particle scattered by the magnetic field of a solenoid. The resulting cross section is symmetric in the scattering angle ... More

Electromagnetic fields from contact formsNov 12 2008In this short note we prove that every contact form on a 3-manifold M induces a solution to Maxwell's equations on M.

Thermal free energy of large Nf QED in 2+1 dimensions from weak to strong couplingAug 26 2019In 2+1 dimensions, QED becomes exactly solvable for all values of the fermion charge $e$ in the limit of many fermions $N_f\gg 1$. We present results for the free energy density at finite temperature $T$ to next-to-leading-order in large $N_f$. In the ... More

(2+)-replication and the Baby MonsterOct 03 2017Jun 19 2018The definitions of replicable and completely replicable functions are intimately related to the Hecke operators for the modular group. We define the notions of "$(2+)$-replicable" and "completely $(2+)$-replicable" functions by considering the Hecke operators ... More

Convergence of a one dimensional Cahn-Hilliard equation with degenerate mobilityOct 16 2015We consider a one dimensional periodic forward-backward parabolic equation, regularized by a non-linear fourth order term of order $\epsilon^2\ll 1$. This equation is known in the literature as Cahn-Hilliard equation with degenerate mobility. Under the ... More

Constraints on Binary Black Hole Populations from LIGO-Virgo DetectionsJun 27 2018Jan 17 2019We reanalyse the LIGO-Virgo strain data of the 10 binary black hole mergers reported to date and compute the likelihood function in terms of chirp mass, mass ratio and effective spin. We discuss the strong degeneracy between mass ratio and spin for the ... More

Role of Van der Waals forces in graphene adsorption over Pd, Pt and NiFeb 28 2013We report ab initiocomputations with the Vienna ab Initio Simulation Package (VASP) aimed at elucidating the adsorption mechanism of graphene-like structures on (111) Pd, Pt, and Ni surfaces. To study the adsorption properties, we simulate an already-formed ... More

On the subdivision of small categoriesJul 11 2007Feb 22 2008We present an intrinsic and concrete development of the subdivision of small categories, give some simple examples and derive its fundamental properties. As an application, we deduce an alternative way to compare the homotopy categories of spaces and ... More

Towards the quality improvement of cross-platform mobile applicationsJan 24 2017Mar 02 2017During last ten years, the number of smartphones and mobile applications has been constantly growing. Android, iOS and Windows Mobile are three mobile platforms that cover almost all smartphones in the world in 2017. Developing a mobile app involves first ... More

Affinity Prediction in Online Social NetworksAug 12 2014Link prediction is the problem of inferring whether potential edges between pairs of vertices in a graph will be present or absent in the near future. To perform this task it is usual to use information provided by a number of available and observed vertices/edges. ... More

Mining Software Repair Models for Reasoning on the Search Space of Automated Program FixingNov 14 2013This paper is about understanding the nature of bug fixing by analyzing thousands of bug fix transactions of software repositories. It then places this learned knowledge in the context of automated program repair. We give extensive empirical results on ... More

On the Relative Projective SpaceOct 20 2017Dec 03 2018Let $(\mathcal C,\otimes,\mathbb 1)$ be an abelian symmetric monoidal category satisfying certain exactness conditions. In this paper we define a presheaf $\mathbb P^{n}_{\mathcal C}$ on the category of commutative algebras in $\mathcal C$ and we prove ... More

Testing the Dark Matter Annihilation Model for the WMAP HazeApr 07 2010Mar 07 2011Analyses have found a "haze" of anomalous microwave emission surrounding the Galactic Center in the WMAP sky maps. A recent study using Fermi data detected a similar haze in the gamma-ray. Several studies have modeled these hazes as radiation from the ... More

On Loops in InflationDec 14 2009We study loop corrections to correlation functions of inflationary perturbations. Previous calculations have found that the two-point function can have a logarithmic running of the form log(k/mu), where k is the wavenumber of the perturbation, and mu ... More

Distance determination to 12 Type II Supernovae using the Expanding Photosphere MethodOct 30 2008We used early time photometry and spectroscopy of 12 Type II plateau Supernovae (SNe IIP) to derive their distances using the Expanding Photosphere Method (EPM). We performed this study using two sets of Type II supernovae (SNe II) atmosphere models (E96, ... More

Asymptotic and coarse Lipschitz structures of quasi-reflexive Banach spacesMay 01 2017In this note, we extend to the setting of quasi-reflexive spaces a classical result of N. Kalton and L. Randrianarivony on the coarse Lipschitz structure of reflexive and asymptotically uniformly smooth Banach spaces. As an application, we show for instance, ... More

The Small-Scale Power Spectrum of Cold Dark MatterApr 05 2005May 13 2005One of the best motivated hypotheses in cosmology states that most of the matter in the universe is in the form of weakly-interacting massive particles that decoupled early in the history of the universe and cooled adiabatically to an extremely low temperature. ... More

Complete connections on fiber bundlesDec 11 2015Jan 10 2017Every smooth fiber bundle admits a complete (Ehresmann) connection. This result appears in several references, with a proof on which we have found a gap, that does not seem possible to remedy. In this note we provide a definite proof for this fact, explain ... More

CMB Anisotropies from a Gradient ModeSep 16 2014Apr 20 2015A linear gradient mode must have no observable dynamical effect on short distance physics. We confirm this by showing that if there was such a gradient mode extending across the whole observable Universe, it would not cause any hemispherical asymmetry ... More

Neutrino clustering around spherical dark matter halosOct 24 2013Jun 04 2014Cold dark matter halos form within a smoothly distributed background of relic neutrinos -- at least some of which are massive and non-relativistic at late times. We calculate the accumulation of massive neutrinos around spherically collapsing cold dark ... More

Characterisation and representation of non-dissipative electromagnetic medium with a double light coneMar 28 2012We study Maxwell's equations on a 4-manifold N with a medium that is non-dissipative and has a linear and pointwise response. In this setting, the medium can be represented by a suitable (2,2)-tensor on the 4-manifold N. Moreover, in each cotangent space ... More

Causality and Primordial Tensor ModesJan 08 2009We introduce the real space correlation function of $B$-mode polarization of the cosmic microwave background (CMB) as a probe of superhorizon tensor perturbations created by inflation. By causality, any non-inflationary mechanism for gravitational wave ... More

Astor: Exploring the Design Space of Generate-and-Validate Program Repair beyond GenProgFeb 09 2018Jan 23 2019During last years, researches have proposed novel repair approaches that automatically generate patches for repairing software bugs. Repair approaches can be loosely characterized along the main design philosophy such generate- and-validate or synthesis-based. ... More

Synchronization in Complex Networks: a Comment on two recent PRL papersJul 20 2005Aug 11 2005I show that the conclusions of [Hwang, Chavez, Amann, & Boccaletti, PRL 94, 138701 (2005); Chavez, Hwang, Amann, Hentschel, & Boccaletti, PRL 94, 218701 (2005)] are closely related to those of previous publications.

CMB 3-point functions generated by non-linearities at recombinationMay 21 2004Sep 15 2004We study the 3-point functions generated at recombination in the squeezed triangle limit, when one mode has a wavelength much larger than the other two and is outside the horizon. The presence of the long wavelength mode cannot change the physics inside ... More

Separating the Early Universe from the Late Universe: cosmological parameter estimation beyond the black boxJul 02 2002Sep 17 2002We present a method for measuring the cosmic matter budget without assumptions about speculative Early Universe physics, and for measuring the primordial power spectrum P*(k) non-parametrically, either by combining CMB and LSS information or by using ... More

New CMB constraints on the cosmic matter budget: trouble for nucleosynthesis?Apr 28 2000Sep 20 2000We compute the joint constraints on ten cosmological parameters from the latest CMB measurements. The lack of a significant second acoustic peak in the latest Boomerang and Maxima data favors models with more baryons than Big Bang nucleosynthesis predicts, ... More

Current cosmological constraints from a 10 parameter CMB analysisFeb 04 2000Oct 03 2000We compute the constraints on a ``standard'' 10 parameter cold dark matter (CDM) model from the most recent CMB and data and other observations, exploring 30 million discrete models and two continuous parameters. Our parameters are the densities of CDM, ... More

Lensing Induced Cluster Signatures in Cosmic Microwave BackgroundJul 19 1999We show that clusters of galaxies induce step-like wiggles on top of the cosmic microwave background (CMB). The direction of the wiggle is parallel to the large scale gradient of CMB allowing one to isolate the effect from other small scale fluctuations. ... More

Some Remarks on the Matching ConditionsJul 14 1994Aug 20 1994We analyze the matching conditions to determine the values that the ${\cal O}(p^4)$ coefficients of an Effective Chiral Lagrangian take in the Standard Model in the limit of a large Higgs mass, pointing out a number of subtleties that appear to have gone ... More

Spectrum of Relativistic Fermions in a 2d Doped LatticeApr 21 1992Motivated by some previous work on fermions on random lattices and by suggestions that impurities could trigger parity breaking in 2d crystals, we have analyzed the spectrum of the Dirac equation on a two dimensional square lattice where sites have been ... More

Minimum Number of Fox Colors for Small PrimesJan 08 2010Apr 09 2011This article concerns exact results on the minimum number of colors of a Fox coloring over the integers modulo r, of a link with non-null determinant. Specifically, we prove that whenever the least prime divisor of the determinant of such a link and the ... More

Boundary control of elliptic solutions to enforce local constraintsOct 15 2012We present a constructive method to devise boundary conditions for solutions of second-order elliptic equations so that these solutions satisfy specific qualitative properties such as: (i) the norm of the gradient of one solution is bounded from below ... More

Do Mobile Developers Ask on Q&A Sites About Error Codes Thrown by a Cross-Platform App Development Framework? An Empirical StudyJan 22 2018During last years development frameworks have emerged to make easier the development and maintenance of cross-platform mobile applications. Xamarin framework is one of them: it takes as input an app written in C# and produces native code for Android, ... More

XamForumDB: a dataset for studying Q&A about cross-platform mobile applications developmentMar 10 2017Android and iSO are the two mobile platforms present in almost all smartphones build during last years. Developing an application that targets both platforms is a challenge. A traditional way is to build two different apps, one in Java for Android, the ... More

Lie Groupoids and their OrbispacesDec 30 2012Jun 10 2013This is a concise introduction to the theory of Lie groupoids, with emphasis in their role as models for orbispaces. After some preliminaries, we review the foundations on Lie groupoids, and we carefully study equivalences and proper groupoids. Orbispaces ... More

Solid-liquid composite structures: elastic beams with embedded liquid-filled parallel-channel networksSep 07 2014Deformation due to embedded fluidic networks is currently studied in the context of soft-actuators and soft-robotics. Expanding on this concept, beams can be designed so that the pressure in the channel-network is created directly from external forces ... More

Knot theory for self-indexed graphsApr 04 2003We introduce and study so-called self-indexed graphs. These are (oriented) finite graphs endowed with a map from the set of edges to the set of vertices. Such graphs naturally arise from classical knot and link diagrams. In fact, the graphs resulting ... More

Pseudogap in cuprates driven by d-wave flux-phase order proximity effects: A theoretical analysis from Raman and ARPES experimentsNov 10 2014One of the puzzling characteristics of the pseudogap phase of high-$T_c$ cuprates is the nodal-antinodal dichotomy. While the nodal quasiparticles have a Fermi liquid behaviour, the antinodal ones show non-Fermi liquid features and an associated pseudogap. ... More

A Note on the Consistency Condition of Primordial FluctuationsMar 30 2012We show that the squeezed limit of (N+1)-point functions of primordial correlation functions in which one of the modes has a very small wavenumber can be inferred from the spatial variation of locally measured N-point function. We then show how in single ... More

Real-time convolutional networks for sonar image classification in low-power embedded systemsSep 07 2017Deep Neural Networks have impressive classification performance, but this comes at the expense of significant computational resources at inference time. Autonomous Underwater Vehicles use low-power embedded systems for sonar image perception, and cannot ... More

Lagrangian Formulation of the Eulerian-EFTNov 05 2015We study the counter terms in the Eulerian version of the EFT of Large Scale Structure. We reformulate the equations to solve for the displacement of fluid elements as a bookkeeping variable and study the structure of the counter terms in this formulation. ... More

Statistical clustering of temporal networks through a dynamic stochastic block modelJun 24 2015Jun 22 2016Statistical node clustering in discrete time dynamic networks is an emerging field that raises many challenges. Here, we explore statistical properties and frequentist inference in a model that combines a stochastic block model (SBM) for its static part ... More

Probing the Friedmann equation during recombination with future CMB experimentsDec 17 2002Mar 26 2003We show that by combining measurements of the temperature and polarization anisotropies of the Cosmic Microwave Background (CMB), future experiments will tightly constrain the expansion rate of the universe during recombination. A change in the expansion ... More

Changing alpha With Time: Implications For Fifth-Force-Type Experiments And QuintessenceAug 26 2001If the recent observations suggesting a time variation of the fine structure constant are correct, they imply the existence of an ultra light scalar particle. This particle inevitably couples to nucleons through the \alpha-dependence of their masses and ... More

Regularization Methods in Chiral Perturbation TheoryJul 13 1993Chiral lagrangians describing the interactions of Goldstone bosons in a theory possessing spontaneous symmetry breaking are effective, non-renormalizable field theories in four dimensions. Yet, in a momentum expansion one is able to extract definite, ... More

A Hydrodynamical Approach to CMB mu-distortionsJun 20 2012Spectral distortion of the cosmic microwave background provides a unique opportunity to probe primordial perturbations on very small scales by performing large-scale measurements. We discuss in a systematic and pedagogic way all the relevant physical ... More

A restatement of the normal form theorem for area metricsAug 21 2011Dec 28 2011An area metric is a (0,4)-tensor with certain symmetries on a 4-manifold that represent a non-dissipative linear electromagnetic medium. A recent result by Schuller, Witte and Wohlfarth provides a pointwise normal form theorem for such area metrics. This ... More

Learning Objectness from Sonar Images for Class-Independent Object DetectionJul 01 2019Detecting novel objects without class information is not trivial, as it is difficult to generalize from a small training set. This is an interesting problem for underwater robotics, as modeling marine objects is inherently more difficult in sonar images, ... More

Best Practices in Convolutional Networks for Forward-Looking Sonar Image RecognitionSep 08 2017Convolutional Neural Networks (CNN) have revolutionized perception for color images, and their application to sonar images has also obtained good results. But in general CNNs are difficult to train without a large dataset, need manual tuning of a considerable ... More

Improving Sonar Image Patch Matching via Deep LearningSep 07 2017Matching sonar images with high accuracy has been a problem for a long time, as sonar images are inherently hard to model due to reflections, noise and viewpoint dependence. Autonomous Underwater Vehicles require good sonar image matching capabilities ... More

A twisted FZZ-like dual for the two-dimensional black holeMay 31 2007Sep 13 2008We review and study the duality between string theory formulated on a curved exact background (the two dimensional black hole) and string theory in flat space with a tachyon-like potential. We generalize previous results in this subject by discussing ... More

Eavesdropping on Radio Broadcasts from Galactic Civilizations with Upcoming Observatories for Redshifted 21cm RadiationOct 12 2006Nov 19 2006The question of whether intelligent life exists elsewhere is one of the fundamental unknowns about our Universe. Over the past decade more than 200 extra-solar planets have been discovered, providing new urgency for addressing this question in these or ... More

Single field consistency relation for the 3-point functionJul 02 2004Oct 19 2004We point out the existence of a consistency relation involving the 3-point function of scalar perturbations which is valid in any inflationary model, independently of the inflaton Lagrangian under the assumption that the inflaton is the only dynamical ... More

On rack cohomologyJan 29 2002Oct 15 2004We prove that the lower bounds for Betti numbers of the rack, quandle and degeneracy cohomology given by Carter, Jelsovsky, Kamada, and Saito, are in fact equalities. We compute as well the Betti numbers of the twisted cohomology introduced by Carter, ... More

Searching for New Physics in Non-Leptonic B DecaysJun 07 1999Nov 26 1999We present allowed regions in the space of observables of certain non-leptonic B-meson decays that characterize these modes within the Standard Model. A future measurement of observables lying significantly outside of these regions would indicate the ... More

Path Integral Invariance under Point TransformationsMar 25 1997Jan 05 1998We give here a covariant definition of the path integral formalism for the Lagrangian, which leaves a freedom to choose anyone of many possible quantum systems that correspond to the same classical limit without adding new potential terms nor searching ... More

Minimum Number of Colors: the Turk's Head Knots Case StudyFeb 25 2010The minimum number of colors is a challenging knot invariant since, by definition, its calculation requires taking the minimum over infinitely many minima. In this article we estimate and in some cases calculate the minimum number of colors for the Turk's ... More

Local Boundedness of Weak Solutions to the Diffusive Wave Approximation of the Shallow Water EquationsJun 12 2018Aug 21 2018In this paper we prove that weak solutions to the Diffusive Wave Approximation of the Shallow Water equations $$ \partial_t u - \nabla\cdot ((u-z)^\alpha|\nabla u|^{\gamma-1}\nabla u) = f $$ are locally bounded. Here, $u$ describes the height of the water, ... More

Properties of Galaxies and Groups: Nature versus NurtureSep 08 2011Due to the inherently nonlinear nature of gravity cosmological N-body simulations have become an invaluable tool when the growth of structure is being studied and modelled closer to the present epoch. Large simulations with high dynamical range have made ... More

Discovering novel computer music techniques by exploring the space of short computer programsDec 06 2011Very short computer programs, sometimes consisting of as few as three arithmetic operations in an infinite loop, can generate data that sounds like music when output as raw PCM audio. The space of such programs was recently explored by dozens of individuals ... More

Consistency of the maximum likelihood and variational estimators in a dynamic stochastic block modelMar 11 2019We consider a dynamic version of the stochastic block model, in which the nodes are partitioned into latent classes and the connection between two nodes is drawn from a Bernoulli distribution depending on the classes of these two nodes. The temporal evolution ... More

Coming: a Tool for Mining Change Pattern Instances from Git CommitsOct 19 2018Software repositories such as Git have become a relevant source of information for software engineer researcher. For instance, the detection of Commits that fulfill a given criterion (e.g., bugfixing commits) is one of the most frequent tasks done to ... More

Beyond the Linear-Order Relativistic Effect in Galaxy Clustering: Second-Order Gauge-Invariant FormalismJun 16 2014We present the second-order general relativistic description of the observed galaxy number density in a cosmological framework. The observed galaxy number density is affected by the volume and the source effects, both of which arise due to the mismatch ... More