Results for "Jan P. Boroński"

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On a generalization of the Cartwright-Littlewood fixed point theorem for planar homeomorphismsOct 22 2015We prove a generalization of the fixed point theorem of Cartwright and Littlewood. Namely, suppose $h : \mathbb{R}^2 \to\mathbb{R}^2$ is an orientation preserving planar homeomorphism, and let $C$ be a continuum such that $h^{-1}(C)\cup C$ is acyclic. ... More
On dynamics of the Sierpiński carpetNov 10 2015Nov 28 2017We prove that the Sierpi\'nski curve admits a homeomorphism with strong mixing properties. We also prove that the constructed example does not have Bowen's specification property.
On dynamics of the Sierpiński carpetNov 10 2015We prove that the Sierpi\'nski curve admits a homeomorphism with strong mixing properties. We also prove that the constructed example does not have Bowen's specification property.
On the conjecture of Wood and projective homogeneityJul 14 2016Sep 06 2017In 2005 Kawamura and Rambla, independently, constructed a metric counterexample to Wood's Conjecture from 1982. We exhibit a new nonmetric counterexample of a space $\hat L$, such that $C_0(\hat L,\mathbb{C})$ is almost transitive, and show that it is ... More
On the conjecture of Wood and projective homogeneityJul 14 2016In 2005 Kawamura and Rambla, independently, constructed a metric counterexample to Wood's Conjecture from 1982. We exhibit a new nonmetric counterexample of a space $\hat L$, such that $C_0(\hat L,\mathbb{C})$ is almost transitive, and show that it is ... More
Mixing completely scrambled system existsSep 06 2016We prove that there exists a topologically mixing homeomorphism which is completely scrambled. We also prove that for any integer $n\geq 1$ there is a continuum of topological dimension $n$ supporting a transitive completely scrambled homeomorphism, and ... More
Mixing completely scrambled system existsSep 06 2016Jan 27 2017We prove that there exists a topologically mixing homeomorphism which is completely scrambled. We also prove that for any integer $n\geq 1$ there is a continuum of topological dimension $n$ supporting a transitive completely scrambled homeomorphism, and ... More
Connected neighborhoods in Cartesian products of solenoidsDec 06 2018Given a collection of pairwise co-prime integers $% m_{1},\ldots ,m_{r}$, greater than $1$, we consider the product $\Sigma =\Sigma _{m_{1}}\times \cdots \times \Sigma _{m_{r}}$, where each $\Sigma _{m_{i}}$ is the $m_{i}$-adic solenoid. Answering a question ... More
Prime Ends Dynamics in Parametrised Families of Rotational AttractorsJun 11 2019We provide several new examples in dynamics on the $2$-sphere, with the emphasis on better understanding the induced boundary dynamics of invariant domains in parametrized families. First, motivated by a topological version of the Poincar\'e-Bendixson ... More
All minimal Cantor systems are slowFeb 27 2019May 25 2019We show that every (invertible, or noninvertible) minimal Cantor system embeds in $\mathbb{R}$ with vanishing derivative everywhere. We also study relations between local shrinking and periodic points.
All minimal Cantor systems are slowFeb 27 2019We show that every (invertible, or noninvertible) minimal Cantor system embeds in $\mathbb{R}$ with vanishing derivative everywhere. We also study relations between local shrinking and periodic points.
New exotic minimal sets from pseudo-suspensions of Cantor systemsSep 28 2016We develop a technique, pseudo-suspension, that applies to invariant sets of homeomorphisms of a class of annulus homeomorphisms we describe, Handel-Anosov-Katok (HAK) homeomorphisms, that generalize the homeomorphism first described by Handel. Given ... More
Ample continua in Cartesian products of continuaSep 06 2017Sep 11 2017We show that the Cartesian product of the arc and a solenoid has the fupcon property, therefore answering a question raised by Illanes. This combined with Illanes' result implies that the product of a Knaster continuum and a solenoid has the fupcon property, ... More
Online Optimisation for Online Learning and Control -- From No-Regret to Generalised Error ConvergenceMar 23 2019This paper presents early work aiming at the development of a new framework for the design and analysis of algorithms for online learning based prediction and control. Firstly, we consider the task of predicting values of a function or time series based ... More
A note on fixed points of abelian actions in dimension oneAug 28 2018The result of Boyce and Huneke gives rise to a 1-dimensional continuum, which is the intersection of a descending family of disks, that admits two commuting homeomorphisms without a common fixed point.
Variational inference for count response semiparametric regressionSep 17 2013Fast variational approximate algorithms are developed for Bayesian semiparametric regression when the response variable is a count, i.e. a non-negative integer. We treat both the Poisson and Negative Binomial families as models for the response variable. ... More
The Exploration of Chemical Reaction NetworksJun 24 2019Modern computational chemistry has reached a stage at which massive exploration into chemical reaction space with unprecedented resolution with respect to the number of potentially relevant molecular structures has become possible. Various algorithmic ... More
An online version of Rota's basis conjectureDec 20 2013Oct 03 2014Rota's basis conjecture states that in any square array of vectors whose rows are bases of a fixed vector space the vectors can be rearranged within their rows in such a way that afterwards not only the rows are bases, but also the columns. We discuss ... More
The Ramsey Number $R(3,K_{10}-e)$ and Computational Bounds for $R(3,G)$Aug 30 2013Nov 16 2013Using computer algorithms we establish that the Ramsey number $R(3,K_{10}-e)$ is equal to 37, which solves the smallest open case for Ramsey numbers of this type. We also obtain new upper bounds for the cases of $R(3,K_k-e)$ for $11 \le k \le 16$, and ... More
Neighbor Joining Plus - algorithm for phylogenetic tree reconstruction with proper nodes assignmentOct 08 2013Most of major algorithms for phylogenetic tree reconstruction assume that sequences in the analyzed set either do not have any offspring, or that parent sequences can maximally mutate into just two descendants. The graph resulting from such assumptions ... More
Continuous curves of nonmetric pseudo-arcs and semi-conjugacies to interval mapsJan 07 2017Jan 17 2017In 1985 M. Smith constructed a nonmetric pseudo-arc; i.e. a Hausdorff homogeneous, hereditary equivalent and hereditary indecomposable continuum. Taking advantage of a decomposition theorem of W. Lewis, he obtained it as a long inverse limit of metric ... More
Scalability Model Based on the Concept of GranularityApr 02 2016In the recent years it can be observed increasing popularity of parallel processing using multi-core processors, local clusters, GPU and others. Moreover, currently one of the main requirements the IT users is the reduction of maintaining cost of the ... More
Social Effects in Simple Computer Model of AgeingAug 28 2001A simple evolutionary model for biological ageing is modified such that it requires a minimum population for survival, like in human society. This social effect leads to a transition between extinction and survival of the species.
New Computational Upper Bounds for Ramsey Numbers R(3,k)Oct 22 2012Mar 20 2013Using computational techniques we derive six new upper bounds on the classical two-color Ramsey numbers: R(3,10) <= 42, R(3,11) <= 50, R(3,13) <= 68, R(3,14) <= 77, R(3,15) <= 87, and R(3,16) <= 98. All of them are improvements by one over the previously ... More
Non-penalized variable selection in high-dimensional linear model settings via generalized fiducial inferenceFeb 23 2017Feb 09 2018Standard penalized methods of variable selection and parameter estimation rely on the magnitude of coefficient estimates to decide which variables to include in the final model. However, coefficient estimates are unreliable when the design matrix is collinear. ... More
Atomic and Molecular Systems Driven by Intense Chaotic LightJan 16 2010We investigate dynamics of atomic and molecular systems exposed to intense, shaped chaotic fields and a weak femtosecond laser pulse theoretically. As a prototype example, the photoionization of a hydrogen atom is considered in detail. The net photoionization ... More
Femtosecond Photoionization of Atoms under NoiseSep 03 2007We investigate the effect of incoherent perturbations on atomic photoionization due to a femtosecond mid-infrared laser pulse by solving the time-dependent stochastic Schr\"odinger equation. For a weak laser pulse which causes almost no ionization, an ... More
Optimal Stochastic Enhancement of PhotoionizationDec 01 2006The effect of noise on the nonlinear photoionization of an atom due to a femtosecond pulse is investigated in the framework of the stochastic Schr\"odinger equation. A modest amount of white noise results in an enhancement of the net ionization yield ... More
Ergodic properties of a model for turbulent dispersion of inertial particlesSep 03 2010We study a simple stochastic differential equation that models the dispersion of close heavy particles moving in a turbulent flow. In one and two dimensions, the model is closely related to the one-dimensional stationary Schroedinger equation in a random ... More
Luminous Blue Variables & Mass Loss near the Eddington LimitJan 16 2008During the course of their evolution, massive stars lose a substantial fraction of their initial mass, both through steady winds and through relatively brief eruptions during their Luminous Blue Variable (LBV) phase. This talk reviews the dynamical driving ... More
Features and New Physical Scales in Primordial Observables: Theory and ObservationMay 07 2015Jun 18 2015All cosmological observations to date are consistent with adiabatic, Gaussian and nearly scale invariant initial conditions. These findings provide strong evidence for a particular symmetry breaking pattern in the very early universe (with a close to ... More
Edrei's Conjecture revisitedMar 06 2017Apr 12 2017Motivated by a recent result of Ciesielski and Jasinski we study periodic point free Cantor systems that are conjugate to systems with vanishing derivative everywhere, and more generally locally radially shrinking maps. Our study uncovers a whole spectrum ... More
Transition from ergodic to explosive behavior in a family of stochastic differential equationsMay 12 2011We study a family of quadratic stochastic differential equations in the plane, motivated by applications to turbulent transport of heavy particles. Using Lyapunov functions, we find a critical parameter value $\alpha_{1}=\alpha_{2}$ such that when $\alpha_{2}>\alpha_{1}$ ... More
Neutrino energy reconstruction from one muon and one proton eventsSep 12 2016We propose a new method of selection of high purity charge current quasielastic neutrino events with a good reconstruction of interacting neutrino energy. Performance of the method was verified with several tests using GENIE, NEUT and NuWro Monte Carlo ... More
The coarea formula for Sobolev mappingsDec 01 2001We extend Federer's coarea formula to mappings $f$ belonging to the Sobolev class $W^{1,p}(R^n;R^m)$, $1 \le m < n$, $p>m$, and more generally, to mappings with gradient in the Lorentz space $L^{m,1}(R^n)$. This is accomplished by showing that the graph ... More
Matroids over one-dimensional groupsDec 20 2018We develop the theory of matroids over one-dimensional algebraic groups, with special emphasis on positive characteristic. In particular, we compute the Lindstr\"om valuations and Frobenius flocks of such matroids. Building on work by Evans and Hrushovski, ... More
$1/k$-homogeneous long solenoidsDec 29 2014Oct 11 2017We study nonmetric analogues of Vietoris solenoids. Let $\Lambda$ be an ordered continuum, and let $\vec{p}=\langle p_1,p_2,\dots\rangle$ be a sequence of positive integers. We define a natural inverse limit space $S(\Lambda,\vec{p})$, where the first ... More
A note on Pólya's observation concerning Liouville's functionDec 21 2011We show that a certain weighted mean of the Liouville function lambda(n) is negative. In this sense, we can say that the Liouville function is negative "on average".
The EAS approach for graphical selection consistency in vector autoregression modelsJun 11 2019As evidenced by various recent and significant papers within the frequentist literature, along with numerous applications in macroeconomics, genomics, and neuroscience, there continues to be substantial interest to understand the theoretical estimation ... More
Confrontation of a Double Inflationary Cosmological Model with ObservationsSep 29 1993CDM models with non-scale-free step-like spectra of adiabatic perturbations produced in a realistic double inflationary model are compared with recent observational data. The model contains two additional free parameters relatively to the standard CDM ... More
Multi-modal filtering for non-linear estimationDec 31 2013Multi-modal densities appear frequently in time series and practical applications. However, they cannot be represented by common state estimators, such as the Extended Kalman Filter (EKF) and the Unscented Kalman Filter (UKF), which additionally suffer ... More
A mechanical erosion model for two-phase mass flowsOct 06 2016Erosion, entrainment and deposition are complex and dominant, but yet poorly understood, mechanical processes in geophysical mass flows. Here, we propose a novel, process-based, two-phase, erosion-deposition model capable of adequately describing these ... More
Low mass planet migration in magnetically torqued dead zones - II. Flow-locked and runaway migration, and a torque prescriptionApr 06 2018We examine the migration of low mass planets in laminar protoplanetary discs, threaded by large scale magnetic fields in the dead zone that drive radial gas flows. As shown in Paper I, a dynamical corotation torque arises due to the flow-induced asymmetric ... More
$1/k$-homogeneous long solenoidsDec 29 2014We study nonmetric analogues of Vietoris solenoids. Let $\Lambda$ be an ordered continuum, and let $\vec{p}=\langle p_1,p_2,\dots\rangle$ be a sequence of positive integers. We define a natural inverse limit space $S(\Lambda,\vec{p})$, where the first ... More
THE LYMAN-ALPHA FOREST AT LOW REDSHIFT: TRACING THE DARK MATTER FILAMENTSFeb 27 1995We study the distribution of low-redshift Ly$\alpha$ clouds in a CDM model using numerical simulations including photoionization and cooling of the baryonic component. The ionizing background is found to be efficient enough to keep most of the gas warm ... More
Genetic Paralog Analysis and SimulationsDec 18 2003Using Monte Carlo methods, we simulated the effects of bias in generation and elimination of paralogs on the size distribution of paralog groups. It was found that the function describing the decay of the number of paralog groups with their size depends ... More
Real-time semiparametric regressionSep 17 2012Feb 06 2013We develop algorithms for performing semiparametric regression analysis in real time, with data processed as it is collected and made immediately available via modern telecommunications technologies. Our definition of semiparametric regression is quite ... More
A mechanical model for phase-separation in debris flowOct 12 2016Understanding the physics of phase-separation between solid and fluid phases as a mixture mass moves down slope is a long-standing challenge. Here, we propose an extension of the two phase mass flow model (Pudasaini, 2012) by including a new mechanism, ... More
PackLib^2: An integrated library of multi-dimensional packing problemsSep 07 2005We present PackLib^2, the first fully integrated benchmark library for multi-dimensional packing instances. PackLib^2 combines a systematic collection of all benchmark instances from previous literature with a well-organized set of new and challenging ... More
Temperature dependent determination of electron heat capacity and electron-phonon factor for Fe$_{0.72}$Cr$_{0.18}$Ni$_{0.1}$Jun 18 2015A theoretical approach using ab initio calculations has been applied to study the interaction of an ultra-short laser pulse with the metal alloy Fe$_{0.72}$Cr$_{0.18}$Ni$_{0.1}$ (AISI 304). The electronic structure is simulated by taking into account ... More
Non-adiabatic molecular association in thermal gases driven by radio-frequency pulsesMar 04 2019The molecular association process in a thermal gas of $^{85}$Rb is investigated where the effects of the envelope of the radio-frequency field are taken into account. For experimentally relevant parameters our analysis shows that with increasing pulse ... More
Minimal cut-off vacuum state constraints from CMB bispectrum statisticsSep 28 2010In this short note we translate the best available observational bounds on the CMB bispectrum amplitudes into constraints on a specific scale-invariant New Physics Hypersurface (NPH) model of vacuum state modifications, as first proposed by Danielsson, ... More
Revisiting Quasiparticle Scattering Interference in High-Temperature Superconductors: The Problem of Narrow PeaksJul 11 2017Oct 10 2017We revisit the interpretation of quasiparticle scattering interference in cuprate high-$T_c$ superconductors. This phenomenon has been very successful in reconstructing the dispersions of d-wave Bogoliubov excitations, but the successful identification ... More
Cooling Stochastic Quantization with colored noiseMay 17 2017Mar 13 2019Smoothing of field configurations is highly important for precision calculations of physical quantities on the lattice. We present a cooling method based on Stochastic Quantization with a built-in UV momentum cutoff. The latter is implemented via a UV-regularized, ... More
Skyrme RPA for spherical and axially symmetric nucleiOct 05 2015Apr 28 2017Random Phase Approximation (RPA) is the basic method for calculation of excited states of nuclei over the Hartree-Fock ground state, suitable also for energy density functionals (EDF or DFT). We developed a convenient formalism for expressing densities ... More
An Efficient Data Structure for Dynamic Two-Dimensional ReconfigurationFeb 24 2017In the presence of dynamic insertions and deletions into a partially reconfigurable FPGA, fragmentation is unavoidable. This poses the challenge of developing efficient approaches to dynamic defragmentation and reallocation. One key aspect is to develop ... More
A Competitive Strategy for Distance-Aware Online Shape AllocationApr 22 2013We consider the following online allocation problem: Given a unit square S, and a sequence of numbers n_i between 0 and 1, with partial sum bounded by 1; at each step i, select a region C_i of previously unassigned area n_i in S. The objective is to make ... More
High spatial entanglement via chirped quasi-phase-matched optical parametric down-conversionAug 22 2012Nov 14 2012By making use of the spatial shape of paired photons, parametric down-conversion allows the generation of two-photon entanglement in a multidimensional Hilbert space. How much entanglement can be generated in this way? In principle, the infinite-dimensional ... More
WMAP 7 Constraints on Oscillations in the Primordial Power SpectrumSep 24 2011We use the WMAP 7 data to place constraints on oscillations supplementing an almost scale-invariant primordial power spectrum. Such oscillations are predicted by a variety of models, some of which amount to assuming there is some non-trivial choice of ... More
Fragmentation of vertically stratified gaseous layers: monolithic or coalescence-driven collapseJan 10 2017We investigate, using 3D hydrodynamic simulations, the fragmentation of pressure-confined, vertically stratified, self-gravitating gaseous layers. The confining pressure is either thermal pressure acting on both surfaces, or thermal pressure acting on ... More
Chance-constrained Model Predictive Control for Multi-Agent SystemsApr 28 2011Aug 16 2011We consider stochastic model predictive control of a multi-agent systems with constraints on the probabilities of inter-agent collisions. We first study a sample-based approximation of the collision probabilities and use this approximation to formulate ... More
Magnetization signatures of light-induced quantum Hall edge statesAug 28 2014Jun 24 2015Circularly polarised light opens a gap in the Dirac spectrum of graphene and topological insulator (TI) surfaces, thereby inducing a quantum Hall-like phase. We propose to detect the accompanying edge states and their current by the magnetic field they ... More
The impact of sloshing on the intra-group medium and old radio lobe of NGC 5044Oct 08 2013Oct 23 2013We present temperature and abundance maps of the central 125 kpc of the NGC 5044 galaxy group, based an a deep XMM-Newton observation. The abundance map reveals an asymmetrical abundance structure, with the centroid of the highest abundance gas offset ... More
A deterministic polynomial kernel for Odd Cycle Transversal and Vertex Multiway Cut in planar graphsOct 02 2018Dec 12 2018We show that Odd Cycle Transversal and Vertex Multiway Cut admit deterministic polynomial kernels when restricted to planar graphs and parameterized by the solution size. This answers a question of Saurabh. On the way to these results, we provide an efficient ... More
Evolution of the Ly$α$ forest: a consistent pictureAug 28 1995We study the evolution with redshift of the number density of Ly$\alpha$ clouds in a CDM model using numerical simulations including photo-ionization and cooling of the baryonic component. The photo-ionizing flux is consistently taken as proportional ... More
Cooling Stochastic Quantization with colored noiseMay 17 2017Smoothing of field configurations is highly important for precision calculations of physical quantities on the lattice. We present a cooling method based on Stochastic Quantization with a built-in UV momentum cutoff. The latter is implemented via a UV-regularized, ... More
Holographic Schwinger-Keldysh effective field theoriesDec 14 2018We construct a holographic dual of the Schwinger-Keldysh effective action for the dissipative low-energy dynamics of relativistic charged matter at strong coupling in a fixed thermal background. To do so, we use a mixed signature bulk spacetime whereby ... More
Correlations in a band insulatorJul 07 2009Oct 16 2009We study a model of a covalent band insulator with on-site Coulomb repulsion at half-filling using dynamical mean-field theory. Upon increasing the interaction strength the system undergoes a discontinuous transition from a correlated band insulator to ... More
Computer Self-efficacy and Its Relationship with Web Portal Usage: Evidence from the University of the EastJul 08 2017The University of the East Web Portal is an academic, web based system that provides educational electronic materials and e-learning services. To fully optimize its usage, it is imperative to determine the factors that relate to its usage. Thus, this ... More
Extended Hubbard model with renormalized Wannier wave functions in the correlated state III: Statistically consistent Gutzwiller approximation and the metallization of atomic solid hydrogenFeb 14 2013Jul 03 2014We extend our previous approach (Eur. Phys. J. B, \textbf{74}, 63(2010)) to modeling correlated electronic states and the metal-insulator transition by applying the so-called \emph{statistically consistent Gutzwiller approximation} (SGA) to carry out ... More
Effective actions for relativistic fluids from holographyApr 28 2015May 21 2015Motivated by recent progress in developing action formulations of relativistic hydrodynamics, we use holography to derive the low energy dissipationless effective action for strongly coupled conformal fluids. Our analysis is based on the study of novel ... More
A relativistic model of the topological acceleration effectSep 07 2011Jul 05 2012It has previously been shown heuristically that the topology of the Universe affects gravity, in the sense that a test particle near a massive object in a multiply connected universe is subject to a topologically induced acceleration that opposes the ... More
Minimal non-invertible maps on the pseudo-circleOct 17 2018In this article, we show that R.H. Bing's pseudo-circle admits a minimal non-invertible map. This resolves a problem raised by Bruin, Kolyada and Snoha in the negative. The main tool is the Denjoy-Rees technique, further developed by B\'eguin-Crovisier-Le ... More
A deformation of AdS_5 x S^5Jun 22 2004Jul 11 2004We analyse a one parameter family of supersymmetric solutions of type IIB supergravity that includes AdS_5 x S^5. For small values of the parameter the solutions are causally well-behaved, but beyond a critical value closed timelike curves (CTC's) appear. ... More
The fragmentation of expanding shells II: Thickness mattersMay 24 2010We study analytically the development of gravitational instability in an expanding shell having finite thickness. We consider three models for the radial density profile of the shell: (i) an analytic uniform-density model, (ii) a semi-analytic model obtained ... More
Skyrme RPA for spherical and axially symmetric nucleiOct 05 2015Dec 17 2015Random Phase Approximation (RPA) is the basic method for calculation of excited states of nuclei over the Hartree-Fock ground state, suitable also for energy density functionals (EDF or DFT). We developed a convenient formalism for expressing densities ... More
An exact algorithm for higher-dimensional orthogonal packingApr 11 2006Higher-dimensional orthogonal packing problems have a wide range of practical applications, including packing, cutting, and scheduling. Combining the use of our data structure for characterizing feasible packings with our new classes of lower bounds, ... More
Dynamics of tunneling into nonequilibrium edge statesMay 23 2014Nov 14 2014Time-dependent perturbations can drive a trivial two-dimensional band insulator into a quantum Hall-like phase, with protected nonequilibrium states bound to its edges. We propose an experiment to probe the existence of these topological edge states which ... More
The hemagglutinin mutation E391K of pandemic 2009 influenza revisitedNov 08 2013Phylogenetic analyses based on small to moderately sized sets of sequential data lead to overestimating mutation rates in influenza hemagglutinin (HA) by at least an order of magnitude. Two major underlying reasons are: the incomplete lineage sorting, ... More
IMEX evolution of scalar fields on curved backgroundsAug 19 2008Jun 27 2009Inspiral of binary black holes occurs over a time-scale of many orbits, far longer than the dynamical time-scale of the individual black holes. Explicit evolutions of a binary system therefore require excessively many time steps to capture interesting ... More
On the behaviour of stellar winds that exceed the photon-tiring limitDec 01 2008Stars can produce steady-state winds through radiative driving as long as the mechanical luminosity of the wind does not exceed the radiative luminosity at its base. This upper bound on the mass loss rate is known as the photon-tiring limit. Once above ... More
Testing the membrane paradigm with holographyMay 16 2014Jan 19 2015One version of the membrane paradigm states that as far as outside observers are concerned, black holes can be replaced by a dissipative membrane with simple physical properties located at the stretched horizon. We demonstrate that such a membrane paradigm ... More
Measurement-based tailoring of Anderson localization of partially coherent lightMar 12 2014May 07 2014We put forward an experimental configuration to observe transverse Anderson localization of partially coherent light beams with a tunable degree of first-order coherence. The scheme makes use of entangled photons propagating in disordered waveguide arrays, ... More
Non-adiabatic molecular association in thermal gases driven by radio-frequency pulsesMar 04 2019May 27 2019The molecular association process in a thermal gas of $^{85}$Rb is investigated where the effects of the envelope of the radio-frequency field are taken into account. For experimentally relevant parameters our analysis shows that with increasing pulse ... More
Holographic Schwinger-Keldysh effective field theoriesDec 14 2018Mar 15 2019We construct a holographic dual of the Schwinger-Keldysh effective action for the dissipative low-energy dynamics of relativistic charged matter at strong coupling in a fixed thermal background. To do so, we use a mixed signature bulk spacetime whereby ... More
Deep ocean early warning signals of an Atlantic MOC collapseMay 06 2014The Atlantic Meridional Overturning Circulation (MOC) is a crucial part of the climate system because of its associated northward heat transport. The present-day MOC is sensitive to freshwater anomalies and may collapse to a state with a strongly reduced ... More
Multiplanet systems in inviscid discs can avoid forming resonant chainsJul 22 2019Convergent migration involving multiple planets embedded in a viscous protoplanetary disc is expected to produce a chain of planets in mean motion resonances, but the multiplanet systems observed by the Kepler spacecraft are generally not in resonance. ... More
Effects of particle stiffness on the extensional rheology of model rod-like nanoparticle suspensionsNov 30 2018The linear and nonlinear rheological behavior of two rod-like particle suspensions as a function of concentration is studied using small amplitude oscillatory shear, steady shear and capillary breakup extensional rheometry. The rod-like suspensions are ... More
Estimation of Large Motion in Lung CT by Integrating Regularized Keypoint Correspondences into Dense Deformable RegistrationJul 02 2018We present a novel algorithm for the registration of pulmonary CT scans. Our method is designed for large respiratory motion by integrating sparse keypoint correspondences into a dense continuous optimization framework. The detection of keypoint correspondences ... More
Can GDP measurement be further improved? Data revision and reconciliationAug 15 2018Recent years have seen many attempts to combine expenditure-side estimates of U.S. real output (GDE) growth with income-side estimates (GDI) to improve estimates of real GDP growth. We show how to incorporate information from multiple releases of noisy ... More
Mapping of the Influenza-A Hemagglutinin Serotypes Evolution by the ISSCOR MethodNov 08 2013Analyses and visualizations by the ISSCOR method of influenza virus hemagglutinin genes of different A-subtypes revealed some rather striking temporal relationships between groups of individual gene subsets. Based on these findings we consider application ... More
Low mass planet migration in Hall-affected disksJun 18 2018Recent developments in non-ideal magnetohydrodynamic simulations of protoplanetary disks suggest that instead of being traditional turbulent (viscous) accretion disks, they have a largely laminar flow with accretion driven by large-scale wind torques. ... More
Forming one of the most massive objects in the Universe: The quadruple merger in Abell 1758Jul 24 2019Abell1758 is a system of two galaxy clusters, a more massive, northern cluster and a southern cluster. Both parts are undergoing major merger events at different stages. Although the mass of the merger constituents provides enough energy to produce visible ... More
Migrating super-Earths in low-viscosity discs: unveiling the roles of feedback, vortices, and laminar accretion flowsNov 30 2018Jan 13 2019We present the highest resolution study to date of super-Earths migrating in inviscid and low-viscosity discs, motivated by the connection to laminar, wind-driven models of protoplanetary discs. Our models unveil the critical role of vortices in determining ... More
Thermodynamics for Fractional Exclusion StatisticsJan 23 1996May 31 1996We discuss the thermodynamics of a gas of free particles obeying Haldane's exclusion statistics, deriving low temperature and low density expansions. For gases with a constant density of states, we derive an exact equation of state and find that temperature-dependent ... More
Low mass planet migration in magnetically torqued dead zones - I. Static migration torqueAug 18 2017Aug 30 2017Motivated by models suggesting that the inner planet forming regions of protoplanetary discs are predominantly lacking in viscosity-inducing turbulence, and are possibly threaded by Hall-effect generated large-scale horizontal magnetic fields, we examine ... More
Drell-Yan process in $pA$ collisions: the exact treatment of coherence effectsAug 09 2016In this work, we investigate production of Drell-Yan (DY) pairs in proton-nucleus collisions in kinematic regions where the corresponding coherence length does not exceed the nuclear radius, $R_A$, and the quantum coherence effects should be treated with ... More
Double, Double Supertube BubbleJul 13 2011Oct 28 2011We argue that there exists a new class of completely smooth 1/8-BPS, three-charge bound state configurations that depend upon arbitrary functions of two variables. These configurations are locally 1/2-BPS objects in that if they form an infinite flat ... More
Continuum Limits of Markov Chains with Application to Network ModelingJun 21 2011In this paper we investigate the continuum limits of a class of Markov chains. The investigation of such limits is motivated by the desire to model very large networks. We show that under some conditions, a sequence of Markov chains converges in some ... More
Colors $-$Messengers of Concepts: Visual Design Mining for Learning Color SemanticsMay 25 2015This paper studies the concept of color semantics by modeling a dataset of magazine cover designs, evaluating the model via crowdsourcing, and demonstrating several prototypes that facilitate color-related design tasks. We investigate a probabilistic ... More