Results for "Matija Vidmar"

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Ruin under stochastic dependence between premium and claim arrivalsFeb 15 2016We investigate, focusing on the ruin probability, an adaptation of the Cramer-Lundberg model for the surplus process of an insurance company, in which, conditionally on their intensities, the two mixed Poisson processes governing the arrival times of ... More
First passage upwards for state dependent-killed spectrally negative Lévy processesMar 13 2018Apr 14 2018For a spectrally negative L\'evy process (snLp) $X$, killed according to a rate that is a function $\omega$ of its position, we analyse the exit probability of the one-sided upwards-passage problem. When $\omega$ is strictly positive, this problem is ... More
Ruin under stochastic dependence between premium and claim arrivalsFeb 15 2016Jun 26 2017We investigate, focusing on the ruin probability, an adaptation of the Cramer-Lundberg model for the surplus process of an insurance company, in which, conditionally on their intensities, the two mixed Poisson processes governing the arrival times of ... More
Exit problems for positive self-similar Markov processes with one-sided jumpsJul 02 2018Mar 06 2019A systematic exposition of scale functions is given for positive self-similar Markov processes (pssMp) with one-sided jumps. The scale functions express as convolution series of the usual scale functions associated with spectrally one-sided L\'evy processes ... More
Observing a Lévy process up to a stopping timeDec 12 2018It is proved that the law of a possibly killed L\'evy process $X$, seen up to and including (resp. up to strictly before) a stopping time, determines already the law of $X$ (resp. up to a compound Poisson component and killing).
On the existence of a minimal generating set for $σ$-algebrasJun 03 2014Does there exist for any $\sigma$-algebra a minimal (with respect to inclusion) generating set? We formulate this problem and answer it in the very special instance of partition generated and standard measurable spaces, the general case remaining open. ... More
A temporal factorization at the maximum for spectrally negative positive self-similar Markov processesMay 10 2018May 15 2018For a spectrally negative positive self-similar Markov process with an a.s. finite overall supremum we provide, in tractable detail, a kind of conditional Wiener-Hopf factorization at the maximum of the absorption time at zero, the conditioning being ... More
Another characterization of homogeneous Poisson processesOct 23 2016Aug 13 2017For a general renewal process $N$ (allowing delay, defect and multiple simultaneous arrivals) the independence of the first renewal epochs of the marked processes got from $N$ by Bernoulli $0$/$1$ thinning is characterized. This independence is well-known ... More
A couple of remarks on the convergence of $σ$-fields on probability spacesJun 09 2016Jun 26 2017The following modes of convergence of sub-$\sigma$-fields on a given probability space have been studied in the literature: weak convergence, strong convergence, convergence with respect to the Hausdorff metric, almost-sure convergence, set-theoretic ... More
A note on the times of first passage for `nearly right-continuous' random walksOct 24 2013Aug 12 2014A natural extension of a right-continuous integer-valued random walk is one which can jump to the right by one or two units. First passage times above a given fixed level then admit a tractable Laplace transform (probability generating function). Explicit ... More
Fluctuation theory for upwards skip-free Lévy chainsSep 20 2013May 18 2015A fluctuation theory and, in particular, a theory of scale functions is developed for upwards skip-free L\'evy chains, i.e. for right-continuous random walks embedded into continuous time as compound Poisson processes. This is done by analogy to the spectrally ... More
Excursions of a spectrally negative Lévy process from a two-point setSep 03 2018Let $a\in (0,\infty)$. For a spectrally negative L\'evy process $X$ with infinite variation paths the resolvent of the process killed on hitting the two-point set $V=\{-a,a\}$ is identified. When further $X$ has no diffusion component the Laplace transforms ... More
First passage problems for upwards skip-free random walks via the $Φ,W,Z$ paradigmAug 21 2017Apr 14 2018We develop the theory of the $W$ and $Z$ scale functions for right-continuous (upwards skip-free) discrete-time discrete-space random walks, along the lines of the analogue theory for spectrally negative L\'evy processes. Notably, we introduce for the ... More
On the informational structure in optimal dynamic stochastic controlMar 09 2015May 15 2018We formulate a very general framework for optimal dynamic stochastic control problems which allows for a control-dependent informational structure. The issue of informational consistency is investigated. Bellman's principle is formulated and proved. In ... More
The structure of non-linear martingale optimal transport problemsMar 15 2019We explore the structure of solutions to a family of non-linear martingale optimal transport (MOT) problems that involve conditional expectations in the objective functional. En route general results concerning optimization over (martingale) measures ... More
Exit problems for positive self-similar Markov processes with one-sided jumpsJul 02 2018A systematic exposition of scale functions is given for positive self-similar Markov processes (pssMp) with one-sided jumps. The scale functions express as convolution series of the usual scale functions associated with spectrally one-sided L\'evy processes ... More
Arithmetic of (independent) sigma-fields on probability spacesSep 14 2018This note gathers what is known about, and provides some new results concerning the operations of intersection, of "generated $\sigma$-field", and of "complementation" for (independent) complete $\sigma$-fields on probability spaces.
Double hypergeometric Lévy processes and self-similarityApr 12 2019Motivated by a recent paper of Budd, where a new family of positive self-similar Markov processes associated to stable processes appears, we introduce a new family of L\'evy processes, called the double hypergeometric class, whose Wiener-Hopf factorisation ... More
Independence times for iid sequences, random walks and Lévy processesApr 20 2017Sep 28 2018For a sequence in discrete time having stationary independent values (respectively, random walk) $X$, those random times $R$ of $X$ are characterized set-theoretically, for which the strict post-$R$ sequence (respectively, the process of the increments ... More
On the existence of a minimal generating set for $σ$-algebrasJun 03 2014May 16 2018Does there exist for any $\sigma$-algebra a minimal (with respect to inclusion) generating set? We formulate this problem and answer it in the very special instance of partition generated and standard measurable spaces, the general case remaining open. ... More
On laws exhibiting universal ordering under stochastic restartApr 23 2019For each of (i) arbitrary stochastic reset, (ii) deterministic reset with arbitrary period, (iii) reset at arbitrary constant rate, and then in the sense of either (a) first-order stochastic dominance or (b) expectation (i.e. for each of the six possible ... More
Proper two-sided exits of a Lévy processNov 24 2015It is proved that the two-sided exits of a Levy process are proper, i.e. not a.s. equal to their one-sided counterparts, if and only if said process is not a subordinator or the negative of a subordinator. Furthermore, Levy processes are characterized, ... More
Another characterization of homogeneous Poisson processesOct 23 2016For a general renewal process $N$ (with delay and defect) the independence of the first renewal epochs of the marked processes got from $N$ by Bernoulli $0$/$1$ thinning is characterized. By way of corollary we obtain a related characterization of homogeneous ... More
A couple of remarks on the convergence of $σ$-fields on probability spacesJun 09 2016The following modes of convergence of sub-$\sigma$-fields on a given probability space have been studied in the literature: weak convergence, strong convergence, convergence with respect to the Hausdorff metric, almost-sure convergence, set-theoretic ... More
Non-random overshoots of Lévy processesJan 18 2013Sep 23 2013The class of Levy processes for which overshoots are almost surely constant quantities is precisely characterized.
Copulas for maxmin systemsDec 30 2015Under a mild condition we give closed-form expressions for copulas of systems that consist of maxima and of minima of subvectors of a given random vector $X$ with continuous marginals. Said expressions appear explicit in the copula of $X$ and the mentioned ... More
On the informational structure in optimal dynamic stochastic controlMar 09 2015Sep 20 2016We formulate a very general framework for optimal dynamic stochastic control problems which allows for a control-dependent informational structure. The issue of informational consistency is investigated. Bellman's principle is formulated and proved. In ... More
Markov chain approximations to scale functions of Lévy processesOct 07 2013Apr 20 2015We introduce a general algorithm for the computation of the scale functions of a spectrally negative L\'evy process $X$, based on a natural weak approximation of $X$ via upwards skip-free continuous-time Markov chains with stationary independent increments. ... More
Markov chain approximations for transition densities of Lévy processesNov 02 2012Jun 26 2013We consider the convergence of a continuous-time Markov chain approximation X^h, h>0, to an R^d-valued Levy process X. The state space of X^h is an equidistant lattice and its Q-matrix is chosen to approximate the generator of X. In dimension one (d=1), ... More
An improved bound for disjoint directed cyclesJan 23 2017Apr 24 2018We show that every directed graph with minimum out-degree at least $18k$ contains at least $k$ vertex disjoint cycles. This is an improvement over the result of Alon who showed this result for digraphs of minimum out-degree at least $64k$. The main benefit ... More
Modular forms, hypergeometric functions and congruencesJan 15 2013Using the theory of Stienstra and Beukers, we prove various elementary congruences for the numbers \sum \binom{2i_1}{i_1}^2\binom{2i_2}{i_2}^2...\binom{2i_k}{i_k}^2, where k,n \in N, and the summation is over the integers i_1, i_2, ...i_k >= 0 such that ... More
Chronology and Sources of Lunar Impact BombardmentNov 30 2011The Moon has suffered intense impact bombardment ending at 3.9 Gyr ago, and this bombardment probably affected all of the inner Solar System. Basin magnetization signatures and lunar crater size-distributions indicate that the last episode of bombardment ... More
Coupled channel analysis of the rho meson decay in lattice QCDMay 27 2011Apr 18 2014We employ a variational basis with a number of $\bar{q}q$ and $\pi\pi$ lattice interpolating fields with quantum numbers of the $\rho$ resonance to extract the discrete energy spectrum in a finite volume. In the elastic region, this spectrum is related ... More
Two holes in the t-J model form a bound state for any nonzero J/tNov 21 2013Determination of the parameter regime in which two holes in the t-J model form a bound state represents a long standing open problem in the field of strongly correlated systems. By applying and systematically improving the exact diagonalization method ... More
Entanglement Entropy of Eigenstates of Quantum Chaotic HamiltoniansAug 28 2017Nov 29 2017In quantum statistical mechanics, it is of fundamental interest to understand how close the bipartite entanglement entropy of eigenstates of quantum chaotic Hamiltonians is to maximal. For random pure states in the Hilbert space, the average entanglement ... More
Diophantine m-tuples in finite fields and modular formsSep 29 2016Jan 31 2018For a prime p, a Diophantine m-tuple in $\mathbb{F}_p$ is a set of m nonzero elements of $\mathbb{F}_p$ with the property that the product of any two of its distinct elements is one less than a square. In this paper, we present formulas for the number ... More
Homology of dendroidal setsSep 02 2015We define for every dendroidal set X a chain complex and show that this assignment determines a left Quillen functor. Then we define the homology groups $H_n(X)$ as the homology groups of this chain complex. This generalizes the homology of simplicial ... More
Student's opinions about System for automatic assessment of programming tasks Projekt TomoFeb 17 2017In a previous paper a web service called Projekt Tomo intended to ease the process of learning programming for teachers and students has been described. Since the service received a very warm welcome from teachers and students alike we decided to collect ... More
Gain of the kinetic energy of bipolarons in the t-J-Holstein model based on electron-phonon couplingAug 19 2010With increasing electron-phonon coupling as described within the t-J-Holstein model, bipolaron kinetic energy is lowered in comparison with that of the polaron. This effect is accompanied with "undressing" of bipolaron from lattice degrees of freedom. ... More
Generalized Gibbs ensemble in integrable lattice modelsApr 13 2016Jun 28 2016The generalized Gibbs ensemble (GGE) was introduced ten years ago to describe observables in isolated integrable quantum systems after equilibration. Since then, the GGE has been demonstrated to be a powerful tool to predict the outcome of the relaxation ... More
Diophantine m-tuples in finite fields and modular formsSep 29 2016For a prime p, a Diophantine m-tuple in $\mathbb{F}_p$ is a set of m nonzero elements of $\mathbb{F}_p$ with the property that the product of any two of its distinct elements is one less than a square. In this paper, we present formulas for the number ... More
Satisfiability Thresholds for Regular Occupation ProblemsNov 02 2018Apr 27 2019In the last two decades the study of random instances of constraint satisfaction problems (CSPs) has flourished across several disciplines, including computer science, mathematics and physics. The diversity of the developed methods, on the rigorous and ... More
Dendroidal sets as models for connective spectraMar 30 2012May 19 2014Dendroidal sets have been introduced as a combinatorial model for homotopy coherent operads. We introduce the notion of fully Kan dendroidal sets and show that there is a model structure on the category of dendroidal sets with fibrant objects given by ... More
On a special case of Watkins' conjectureNov 17 2016Watkins' conjecture asserts that for a rational elliptic curve $E$ the degree of the modular parametrization is divisible by $2^r$, where $r$ is the rank of $E$. In this paper we prove that if the modular degree is odd then $E$ has rank $0$. Moreover, ... More
Extinction Dynamics of Cardiac FibrillationAug 06 2018During episodes of atrial fibrillation, the heart's electrical activity becomes disorganized and shows fragmenting spiral waves. To systematically address how this pattern terminates using spatially extended simulations exceeds current computational resources. ... More
On the Secular Behavior of Irregular SatellitesAug 05 2004Although analytical studies on the secular motion of the irregular satellites have been published recently, these theories have not yet been satisfactorily reconciled with the results of direct numerical integrations. These discrepancies occur because ... More
Dissociation of a Hubbard--Holstein bipolaron driven away from equilibrium by a constant electric fieldNov 29 2011Mar 27 2012Using a variational numerical method we compute the time-evolution of the Holstein-Hubbard bipolaron from its ground state when at t=0 the constant electric field is switched on. The system is evolved taking into account full quantum effects until it ... More
Impenetrable SU(N) fermions in one-dimensional latticesAug 03 2018Oct 26 2018We study SU(N) fermions in the limit of infinite on-site repulsion between all species. We focus on states in which every pair of consecutive fermions carries a different spin flavor. Since the particle order cannot be changed (because of the infinite ... More
Emergent eigenstate solution and emergent Gibbs ensemble for expansion dynamics in optical latticesApr 04 2017Jul 06 2017Within the emergent eigenstate solution to quantum dynamics [Phys. Rev. X 7, 021012 (2017)], one can construct a local operator (an emergent Hamiltonian) of which the time-evolving state is an eigenstate. Here we show that such a solution exists for the ... More
Optical conductivity in the t-J-Holstein ModelDec 11 2008Using recently developed numerical method we compute charge stiffness and optical conductivity of the t-J model coupled to optical phonons. Coherent hole motion is most strongly influenced by the electron-phonon coupling within the physically relevant ... More
Nonequilibrium propagation and decay of a bound pair in driven t-J modelsJul 25 2012Oct 10 2012We perform an accurate time-dependent numerical study of out-of-equilibrium response of a bound state within t-J systems on a two-leg ladder and a square lattice. We show that the bound hole pair decays with the onset of finite steady current if both ... More
Emergence of states in the phonon spectral function of the Holstein polaron below and above the one-phonon continuumAug 19 2010We investigate the low-energy properties of the Holstein polaron through calculation of the q-dependent phonon spectral function using an improved exact-diagonalization technique, defined over a variational Hilbert space. We perform a comprehensive study ... More
Disentangling sources of influence in online social networksNov 26 2018Nov 27 2018Information propagation in online social networks is facilitated by two types of influence - endogenous (peer) influence that is dependent on the network structure and current state of each user and exogenous (external) which is independent of these. ... More
There are infinitely many rational Diophantine sextuples with square denominatorsMar 07 2019A rational Diophantine m-tuple is a set of m nonzero rationals such that the product of any two of them increased by 1 is a perfect square. The first rational Diophantine quadruple was found by Diophantus, while Euler proved that there are infinitely ... More
Directed Ramsey number for treesAug 15 2017Dec 10 2018In this paper, we study Ramsey-type problems for directed graphs. We first consider the $k$-colour oriented Ramsey number of $H$, denoted by $\overrightarrow{R}(H,k)$, which is the least $n$ for which every $k$-edge-coloured tournament on $n$ vertices ... More
Monochromatic paths in random tournamentsMar 30 2017Dec 09 2017We prove that, with high probability, any $2$-edge-colouring of a random tournament on $n$ vertices contains a monochromatic path of length $\Omega(n / \sqrt{\log n})$. This resolves a conjecture of Ben-Eliezer, Krivelevich and Sudakov and implies a nearly ... More
Emergent eigenstate solution to quantum dynamics far from equilibriumDec 16 2015Mar 09 2016Recent studies on the dynamics of interacting quantum many-body systems have shed light into this largely unexplored domain in physics. A unique possibility revealed by such studies is the dynamical realization of novel quantum states. Prominent examples ... More
Information measures for a local quantum phase transition: Lattice fermions in a one-dimensional harmonic trapDec 05 2017Apr 06 2018We use quantum information measures to study the local quantum phase transition that occurs for trapped spinless fermions in one-dimensional lattices. We focus on the case of a harmonic confinement. The transition occurs upon increasing the characteristic ... More
The Complemented System Approach: A Novel Method for Calculating the X-ray Scattering from Computer SimulationsNov 09 2010In this paper, we review the main problem concerning the calculation of X-ray scattering of simulated model systems, namely their finite size. A novel method based on the Rayleigh-Debye-Gans approximation was derived, which allows sidestepping this issue ... More
Multicolour bipartite Ramsey number of pathsJan 17 2019The $k$-colour bipartite Ramsey number of a bipartite graph $H$ is the least integer $N$ for which every $k$-edge-coloured complete bipartite graph $K_{N,N}$ contains a monochromatic copy of $H$. The study of bipartite Ramsey numbers was initiated over ... More
FPGA acceleration of Model Predictive Control for Iter Plasma current and shape controlJun 15 2018A faster implementation of the Quadratic Programming (QP) solver used in the Model Predictive Control scheme for Iter Plasma current and shape control was developed for Xilinx Field-Programmable Gate Array (FPGA) platforms using a high-level synthesis ... More
On the Dynamics and Origin of Haumea's MoonsAug 08 2013The dwarf planet Haumea has two large satellites, Namaka and Hi'iaka, which orbit at relatively large separations. Both moons have significant eccentricities and inclinations, in a pattern that is consistent with a past orbital resonance (Ragozzine and ... More
Covering random graphs by monochromatic trees and Helly-type results for hypergraphsFeb 13 2019Feb 19 2019How many monochromatic paths, cycles or general trees does one need to cover all vertices of a given $r$-edge-coloured graph $G$? These problems were introduced in the 1960's and were intensively studied by various researchers over the last 50 years. ... More
The Arf-Kervaire invariant of framed manifolds as an obstruction to embeddabilityApr 19 2008Aug 17 2010We define a quadratic form which gives an obstruction to embedding $N^{4k+2} \subset \R^{6k+4}$ of a smooth highly connected manifold into Euclidean space, with sufficiently many nondegenerate sections of the normal bundle. As the main corollary we prove ... More
Rigidity of the Minimal Grope GroupAug 04 2006We give a systematic definition of the fundamental groups of gropes, which we call grope groups. We show that there exists a nontrivial homomorphism from the minimal grope group M to another grope group G only if G is the free product of M with another ... More
Rational Diophantine sextuples containing two regular quadruples and one regular quintupleMar 31 2019A set of $m$ distinct nonzero rationals $\{a_1,a_2,\ldots,a_m\}$ such that $a_ia_j+1$ is a perfect square for all $1\leq i<j\leq m$, is called a rational Diophantine $m$-tuple. It is proved recently that there are infinitely many rational Diophantine ... More
Max-min measures on ultrametric spacesFeb 26 2013The ultrametrization of the set of all probability measures of compact support on the ultrametric spaces was first defined by Hartog and de Vink. In this paper we consider a similar construction for the so called max-min measures on the ultrametric spaces. ... More
Covering random graphs by monochromatic trees and Helly-type results for hypergraphsFeb 13 2019How many monochromatic paths, cycles or general trees does one need to cover all vertices of a given $r$-edge-coloured graph $G$? These problems were introduced in the 1960's and were intensively studied by various researchers over the last 50 years. ... More
On structure sets of manifold pairsAug 10 2009In this paper we systematically describe relations between various structure sets which arise naturally for pairs of compact topological manifolds with boundary. Our consideration is based on a deep analogy between the case of a compact manifold with ... More
Modular parametrizations of certain elliptic curvesDec 26 2012Kaneko and Sakai recently observed that certain elliptic curves whose associated newforms (by the modularity theorem) are given by the eta-quotients can be characterized by a particular differential equation involving modular forms and Ramanujan-Serre ... More
Simulating the Phases of the Moon Shortly After Its FormationMar 10 2015The leading theory for the origin of the Moon is the giant impact hypothesis, in which the Moon was formed out of the debris left over from the collision of a Mars-sized body with the Earth. Soon after its formation, the orbit of the Moon may have been ... More
Quantum chaos challenges many-body localizationMay 15 2019Characterizing states of matter through the lens of their ergodic properties is a fascinating new direction of research. In the quantum realm, the many-body localization (MBL) was proposed to be the paradigmatic nonergodic phenomenon, which extends the ... More
Average eigenstate entanglement entropy of the XY chain in a transverse field and its universality for translationally invariant quadratic fermionic modelsDec 20 2018Feb 13 2019We recently showed [Phys. Rev. Lett. 121, 220602 (2018)] that the average bipartite entanglement entropy of all energy eigenstates of the quantum Ising chain exhibits a universal (for translationally invariant quadratic fermionic models) leading term ... More
Eigenstate thermalization and quantum chaos in the Holstein-polaron modelFeb 08 2019The eigenstate thermalization hypothesis (ETH) is a successful theory that provides sufficient criteria for ergodicity in quantum many-body systems. Most studies were carried out for Hamiltonians relevant for ultracold quantum gases and single-component ... More
Relaxation dynamics of the Holstein polaronSep 12 2012Keeping the full quantum nature of the problem we compute the relaxation time of the Holstein polaron after it was driven far from the equilibrium by a strong oscillatory pulse. Just after the pulse the polaron's kinetic energy increases and subsequently ... More
Nonequilibrium quantum dynamics of a charge carrier doped into a Mott insulatorMar 10 2011May 09 2011We study real-time dynamics of a charge carrier introduced into undoped Mott insulator propagating under a constant electric field F on the t-J ladder and square lattice. We calculate quasistationary current. In both systems adiabatic regime is observed ... More
Relaxation and thermalization in the one-dimensional Bose-Hubbard model: A case study for the interaction quantum quench from the atomic limitMay 21 2014Sep 10 2014Motivated by recent experiments, we study the relaxation dynamics and thermalization in the one-dimensional Bose-Hubbard model induced by a global interaction quench. Specifically, we start from an initial state that has exactly one boson per site and ... More
Decay of rho and a1 mesons on the lattice using distillationNov 02 2011We extract the P-wave pi-pi phase shift for five values of pion relative momenta, which gives information on the rho resonance. The Breit-Wigner formula describes the pi-pi phase shift dependence nicely and we extract m(rho)=792(7)(8) MeV and the coupling ... More
Bipolaron in the t-J model coupled to longitudinal and transverse quantum lattice vibrationsAug 21 2009Oct 27 2009We explore the influence of two different polarizations of quantum oxygen vibrations on the spacial symmetry of the bound magnetic bipolaron in the context of the t-J model by using exact diagonalization within a limited functional space. Quadratic electron ... More
Few Islands Approximation of Hamiltonian System with divided Phase SpaceFeb 27 2018Apr 10 2019It is well known that typical Hamiltonian systems have divided phase space consisting of regions with regular dynamics on KAM tori and region(s) with chaotic dynamics called chaotic sea(s). This complex structure makes rigorous analysis of such systems ... More
Quantum Dynamics of a Driven Correlated System Coupled to PhononsJul 06 2011Dec 08 2011Nonequilibrium interplay between charge, spin and lattice degrees of freedom on a square lattice is studied for a single charge carrier doped in the t-J-Holstein model. In the presence of an uniform electric field we calculate the qusistationary state. ... More
Volume Law and Quantum Criticality in the Entanglement Entropy of Excited Eigenstates of the Quantum Ising ModelAug 27 2018Dec 03 2018Much has been learned about universal properties of entanglement entropies in ground states of quantum many-body lattice systems. Here we unveil universal properties of the average bipartite entanglement entropy of eigenstates of the paradigmatic quantum ... More
Halfway to Rota's basis conjectureOct 17 2018In 1989, Rota made the following conjecture. Given $n$ bases $B_{1},\dots,B_{n}$ in an $n$-dimensional vector space $V$, one can always find $n$ disjoint bases of $V$, each containing exactly one element from each $B_{i}$ (we call such bases transversal ... More
There are infinitely many rational Diophantine sextuplesJul 02 2015Nov 30 2015A rational Diophantine m-tuple is a set of m nonzero rationals such that the product of any two of them increased by 1 is a perfect square. The first rational Diophantine quadruple was found by Diophantus, while Euler proved that there are infinitely ... More
Unexpected composition dependence of the first sharp diffraction peak in an alcohol-aldehyde liquid mixture: n-pentanol and pentanalNov 26 2018The total scattering structure factors of pure liquid n-pentanol, pentanal, and 5 of their mixtures, as determined by high energy synchrotron X-ray diffraction experiments, are presented. For the interpretation of measured data, molecular dynamics computer ... More
Mechanism of Ultrafast Relaxation of a Photo-Carrier in Antiferromagnetic Spin BackgroundNov 21 2013May 28 2014We study the relaxation mechanism of a highly excited carrier propagating in the antiferromagnetic background modeled by the $t$-$J$ Hamiltonian on a square lattice. We show that the relaxation consists of two distinct stages. The initial ultrafast stage ... More
Unveiling hidden structure of many-body wavefunctions of integrable systems via sudden expansion experimentsSep 02 2015Feb 22 2016In the theory of Bethe-ansatz integrable quantum systems, rapidities play an important role as they are used to specify many-body states, apart from phases. The physical interpretation of rapidities going back to Sutherland is that they are the asymptotic ... More
Quantum chaos challenges many-body localizationMay 15 2019Jun 06 2019Characterizing states of matter through the lens of their ergodic properties is a fascinating new direction of research. In the quantum realm, the many-body localization (MBL) was proposed to be the paradigmatic nonergodic phenomenon, which extends the ... More
Constraints on the Source of Lunar Cataclysm ImpactorsDec 10 2009Multiple impact basins formed on the Moon about 3.8 Gyr ago in what is known as the lunar cataclysm or late heavy bombardment. Many workers currently interpret the lunar cataclysm as an impact spike primarily caused by main-belt asteroids destabilized ... More
On the Expressive Power of User-Defined Effects: Effect Handlers, Monadic Reflection, Delimited ControlOct 28 2016Feb 28 2017We compare the expressive power of three programming abstractions for user-defined computational effects: Bauer and Pretnar's effect handlers, Filinski's monadic reflection, and delimited control without answer-type-modification. This comparison allows ... More
2-factors with k cycles in Hamiltonian graphsMay 23 2019A well known generalisation of Dirac's theorem states that if a graph $G$ on $n\ge 4k$ vertices has minimum degree at least $n/2$ then $G$ contains a $2$-factor consisting of exactly $k$ cycles. This is easily seen to be tight in terms of the bound on ... More
On the Alexandroff-Borsuk problemMar 03 2017We investigate the classical Alexandroff-Borsuk problem in the category of non-triangulable manifolds: Given an $n$-dimensional compact non-triangulable manifold $M^n$ and $\varepsilon > 0$, does there exist an $\varepsilon$-map of $M^n$ onto an $n$-dimensional ... More
Characterizing compact Clifford semigroups that embed into convolution and functor-semigroupsNov 06 2008Aug 02 2011We study algebraic and topological properties of the convolution semigroups of probability measures on a topological groups and show that a compact Clifford topological semigroup $S$ embeds into the convolution semigroup $P(G)$ over some topological group ... More
On the Expressive Power of User-Defined Effects: Effect Handlers, Monadic Reflection, Delimited ControlOct 28 2016We compare the expressive power of three programming abstractions for user-defined computational effects: Bauer and Pretnar's effect handlers, Filinski's monadic reflection, and delimited control. This comparison allows a precise discussion about the ... More
On the combinatorics of faces of trees and anodyne extensions of dendroidal setsJan 28 2018May 17 2018We discuss the combinatorics of faces of trees in the context of dendroidal sets and develop a systematic treatment of dendroidal anodyne extensions. As the main example and our motivation, we prove the pushout-product property for the stable model structure ... More
Inferring Algebraic EffectsDec 09 2013Sep 11 2014We present a complete polymorphic effect inference algorithm for an ML-style language with handlers of not only exceptions, but of any other algebraic effect such as input & output, mutable references and many others. Our main aim is to offer the programmer ... More
Congruences for sporadic sequences and modular forms for non-congruence subgroupsJan 10 2019In the course of the proof of the irrationality of zeta(2) R. Apery introduced numbers b_n = \sum_{k=0}^n {n \choose k}^2{n+k \choose k}. Stienstra and Beukers showed that for the prime p > 3 Apery numbers satisfy congruence b((p-1)/2) = 4a^2-2p mod p, ... More
Monochromatic trees in random tournamentsSep 19 2018We prove that, with high probability, in every $2$-edge-colouring of the random tournament on $n$ vertices there is a monochromatic copy of every oriented tree of order $O (n / \sqrt{\log n})$. This generalises a result of the first, third and forth authors ... More
X-ray diffraction and computer simulation studies of the structure of liquid aliphatic aldehydes: from propanal to nonanalNov 26 2018Synchrotron X-ray diffraction experiments and molecular dynamics simulations have been performed on simple aliphatic aldehydes, from propanal to nonanal. The performance of the OPLS all-atom interaction potential model for aldehydes has been assessed ... More
Long-Term Stability of Horseshoe OrbitsJun 08 2012Aug 24 2012Unlike Trojans, horseshoe coorbitals are not generally considered to be long-term stable (Dermott and Murray, 1981; Murray and Dermott, 1999). As the lifetime of Earth's and Venus's horseshoe coorbitals is expected to be about a Gyr, we investigated the ... More