Results for "Dániel T. Nagy"

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Density of 4-edge paths in graphs with fixed edge densityJan 06 2016We investigate the number of 4-edge paths in graphs with a fixed number of vertices and edges. An asymptotically sharp upper bound is given to this quantity. The extremal construction is the quasi-star or the quasi-clique graph, depending on the edge ... More
Forbidden subposet problems with size restrictionsAug 23 2016Upper bounds to the size of a family of subsets of an n-element set that avoids certain configurations are proved. These forbidden configurations can be described by inclusion patterns and some sets having the same size. Our results are closely related ... More
The method of double chains for largest families with excluded subposetsApr 24 2012For a given finite poset $P$, $La(n,P)$ denotes the largest size of a family $\mathcal{F}$ of subsets of $[n]$ not containing $P$ as a weak subposet. We exactly determine $La(n,P)$ for infinitely many $P$ posets. These posets are built from seven base ... More
t-wise Berge and t-heavy hypergraphsFeb 08 2019In many proofs concerning extremal parameters of Berge hypergraphs one starts with analyzing that part of that shadow graph which is contained in many hyperedges. Capturing this phenomenon we introduce two new types of hypergraphs. A hypergraph $\mathcal{H}$ ... More
On the maximum number of copies of H in graphs with given size and orderOct 01 2018We study the maximum number $ex(n,e,H)$ of copies of a graph $H$ in graphs with given number of vertices and edges. We show that for any fixed graph $H$, $ex(n,e,H)$ is asymptotically realized by the quasi-clique provided that the edge density is sufficiently ... More
Incomparable copies of a poset in the Boolean latticeSep 27 2013Let $B_n$ be the poset generated by the subsets of $[n]$ with the inclusion as relation and let $P$ be a finite poset. We want to embed $P$ into $B_n$ as many times as possible such that the subsets in different copies are incomparable. The maximum number ... More
Union-intersecting set systemsMar 01 2014Three intersection theorems are proved. First, we determine the size of the largest set system, where the system of the pairwise unions is l-intersecting. Then we investigate set systems where the union of any s sets intersect the union of any t sets. ... More
Squares and their centersAug 05 2014Aug 24 2014We study the relationship between the sizes of two sets $B, S\subset\mathbb{R}^2$ when $B$ contains either the whole boundary, or the four vertices, of a square with axes-parallel sides and center in every point of $S$, where size refers to one of cardinality, ... More
PHENIX results on Lévy analysis of Bose-Einstein correlation functionsOct 17 2016The nature of the quark-hadron phase transition can be investigated through analyzing the space-time structure of the hadron emission source. For this, the Bose-Einstein or HBT correlations of identified charged particles are among the best observables. ... More
Maps on probability measures preserving certain distances --- a survey and some new resultsFeb 09 2018Mar 19 2018Borel probability measures living on metric spaces are fundamental mathematical objects. There are several meaningful distance functions that make the collection of the probability measures living on a certain space a metric space. We are interested in ... More
On the number of containments in $P$-free familiesApr 04 2018A subfamily $\{F_1,F_2,\dots,F_{|P|}\}\subseteq \mathcal F$ is a copy of the poset $P$ if there exists a bijection $i:P\rightarrow \{F_1,F_2,\dots,F_{|P|}\}$ such that $p\le_P q$ implies $i(p)\subseteq i(q)$. A family $\mathcal F$ is $P$-free, if it does ... More
Forbidding rank-preserving copies of a posetOct 25 2017The maximum size, $La(n,P)$, of a family of subsets of $[n]=\{1,2,...,n\}$ without containing a copy of $P$ as a subposet, has been intensively studied. Let $P$ be a graded poset. We say that a family $\mathcal{F}$ of subsets of $[n]=\{1,2,...,n\}$ contains ... More
Vertex Turán problems for the oriented hypercubeJul 18 2018In this short note we consider the oriented vertex Tur\'an problem in the hypercube: for a fixed oriented graph $\overrightarrow{F}$, determine the maximum size $ex_v(\overrightarrow{F}, \overrightarrow{Q_n})$ of a subset $U$ of the vertices of the oriented ... More
Triangle areas determined by arrangements of planar linesFeb 08 2019A widely investigated subject in combinatorial geometry, originated from Erd\H{o}s, is the following. Given a point set $P$ of cardinality $n$ in the plane, how can we describe the distribution of the determined distances? This has been generalized in ... More
On the joint convexity of the Bregman divergence of matricesMay 30 2014Apr 23 2015We characterize the functions for which the corresponding Bregman divergence is jointly convex on matrices. As an application of this characterization, we derive a sharp inequality for the quantum Tsallis entropy of a tripartite state, which can be considered ... More
On the equations and classification of toric quiver varietiesFeb 20 2014Toric quiver varieties (moduli spaces of quiver representations) are studied. Given a quiver and a weight there is an associated quasiprojective toric variety together with a canonical embedding into projective space. It is shown that for a quiver with ... More
Chordal Editing is Fixed-Parameter TractableMay 30 2014Graph modification problems are typically asked as follows: is there a small set of operations that transforms a given graph to have a certain property. The most commonly considered operations include vertex deletion, edge deletion, and edge addition; ... More
Toric quiver cellsSep 12 2016Jul 03 2017It is shown that up to dimension four, the toric ideal of a quiver polytope is generated in degree two, with the only exception of the four-dimensional Birkhoff polytope. As a consequence, B{\o}gvad's conjecture holds for quiver polytopes of dimension ... More
Extremal results for Berge-hypergraphsMay 29 2015Let $G$ be a graph and $\mathcal{H}$ be a hypergraph both on the same vertex set. We say that a hypergraph $\mathcal{H}$ is a \emph{Berge}-$G$ if there is a bijection $f : E(G) \rightarrow E(\mathcal{H})$ such that for $e \in E(G)$ we have $e \subset ... More
A faster FPT algorithm for Bipartite ContractionMay 13 2013Sep 04 2013The \textsc{Bipartite Contraction} problem is to decide, given a graph $G$ and a parameter $k$, whether we can can obtain a bipartite graph from $G$ by at most $k$ edge contractions. The fixed-parameter tractability of the problem was shown by [Heggernes ... More
Adaptive Majority Problems for Restricted Query Graphs and for Weighted SetsMar 20 2019Suppose that the vertices of a graph $G$ are colored with two colors in an unknown way. The color that occurs on more than half of the vertices is called the majority color (if it exists), and any vertex of this color is called a majority vertex. We study ... More
An Application of the Separator of Subsets of Semigroups in the Number TheoryJan 21 2015Jun 01 2015In this paper we give a construction for a special type of congruences on commutative semigroups. We apply our result for the multiplicative semigroup of all positive integers.
Separators of Ideals in Multiplicative Semigroups of Unique Factorization DomainsAug 29 2015In this paper we show that if $I$ is an ideal of a commutative semigroup $C$ such that the separator $SepI$ of $I$ is not empty then the factor semigroup $S=C/P_I$ ($P_I$ is the principal congruence on $C$ defined by $I$) satisfies Condition $(*)$: $S$ ... More
Stability results on vertex Turán problems in Kneser graphsApr 11 2018Apr 20 2018The vertex set of the Kneser graph $K(n,k)$ is $V = \binom{[n]}{k}$ and two vertices are adjacent if the corresponding sets are disjoint. For any graph $F$, the largest size of a vertex set $U \subseteq V$ such that $K(n,k)[U]$ is $F$-free, was recently ... More
Stability results on vertex Turán problems in Kneser graphsApr 11 2018Mar 07 2019The vertex set of the Kneser graph $K(n,k)$ is $V = \binom{[n]}{k}$ and two vertices are adjacent if the corresponding sets are disjoint. For any graph $F$, the largest size of a vertex set $U \subseteq V$ such that $K(n,k)[U]$ is $F$-free, was recently ... More
Orientations of graphs with uncountable chromatic numberAug 24 2016Nov 09 2017Motivated by an old conjecture of P. Erd\H{o}s and V. Neumann-Lara, our aim is to investigate digraphs with uncountable dichromatic number and orientations of undirected graphs with uncountable chromatic number. A graph has uncountable chromatic number ... More
Two infinite quantities and their surprising relationshipMar 12 2018As early as the 17th century, Galileo Galilei wondered how to compare the sizes of infinite sets. Fast forward almost four hundred years, and in the summer of 2017, at the 6th European Set Theory Conference, a young model theorist, Maryanthe Malliaris, ... More
A model with Suslin trees but no minimal uncountable linear orders other than $ω_1$ and $-ω_1$Mar 09 2018Mar 12 2018We show that the existence of a Suslin tree does not necessarily imply that there are uncountable minimal linear orders other than $\omega_1$ and $-\omega_1$, answering a question of J. Baumgartner. This is done by a Jensen-type iteration, proving that ... More
$\mathcal{O}(k)$-robust spanners in one dimensionMar 23 2018A geometric $t$-spanner on a set of points in Euclidean space is a graph containing for every pair of points a path of length at most $t$ times the Euclidean distance between the points. Informally, a spanner is $\mathcal{O}(k)$-robust if deleting $k$ ... More
Orientations of graphs with uncountable chromatic numberAug 24 2016A graph (digraph) has uncountable chromatic number if its vertices cannot be covered by countably many independent (acyclic) sets. Our aim is to investigate digraphs with uncountable chromatic number and orientations of undirected graphs with uncountable ... More
Ladder system uniformization on trees I & IIJun 11 2018Jan 04 2019Given a tree $T$ of height $\omega_1$, we say that a ladder system colouring $(f_\alpha)_{\alpha\in \lim\omega_1}$ has a $T$-uniformization if there is a function $\varphi$ defined on a subtree $S$ of $T$ so that for any $s\in S_\alpha$ of limit height ... More
Uncountable strongly surjective linear ordersJun 30 2017Jan 30 2018A linear order $L$ is strongly surjective if $L$ can be mapped onto any of its suborders in an order preserving way. We prove various results on the existence and non-existence of uncountable strongly surjective linear orders answering questions of Camerlo, ... More
Trees, ladders and graphsSep 09 2014We introduce a new method to construct uncountably chromatic graphs from non special trees and ladder systems. Answering a question of P. Erd\H{o}s and A. Hajnal from 1985, we construct graphs of chromatic number $\omega_1$ without uncountable $\omega$-connected ... More
Quantum Algorithms for Portfolio OptimizationAug 22 2019We develop the first quantum algorithm for the constrained portfolio optimization problem. The algorithm has running time $\widetilde{O} \left( n\sqrt{r} \frac{\zeta \kappa}{\delta^2} \log \left(1/\epsilon\right) \right)$, where $r$ is the number of positivity ... More
On isometric embeddings of Wasserstein spaces -- the discrete caseSep 04 2018Aug 22 2019The aim of this short paper is to offer a complete characterization of all (not necessarily surjective) isometric embeddings of the Wasserstein space $\mathcal{W}_p(\mathcal{X})$, where $\mathcal{X}$ is a countable discrete metric space and $0<p<\infty$ ... More
Finding and counting permutations via CSPsAug 13 2019Permutation patterns and pattern avoidance have been intensively studied in combinatorics and computer science, going back at least to the seminal work of Knuth on stack-sorting (1968). Perhaps the most natural algorithmic question in this area is deciding ... More
On random approximations by generalized disc-polygonsJul 03 2019For two convex discs $K$ and $L$, we say that $K$ is $L$-convex if it is equal to the intersection of all translates of $L$ that contain $K$. In $L$-convexity the set $L$ plays a similar role as closed half-spaces do in the classical notion of convexity. ... More
The Abel map for surface singularities I. Generalities and examplesSep 11 2018Let $(X,o)$ be a complex normal surface singularity. We fix one of its good resolutions $\widetilde{X}\to X$, an effective cycle $Z$ supported on the reduced exceptional curve, and any possible (first Chern) class $l'\in H^2(\widetilde{X},\mathbb{Z})$. ... More
Motivic Poincaré series of cusp surface singularitiesJul 28 2019We target multivariable series associated with resolutions of complex analytic normal surface singularities. In general, the equivariant multivariable analytical and topological Poincar\'e series are well-defined and have good properties only if the link ... More
Topological Analysis of Bitcoin's Lightning NetworkJan 15 2019Apr 14 2019Bitcoin's Lightning Network (LN) is a scalability solution for Bitcoin allowing transactions to be issued with negligible fees and settled instantly at scale. In order to use LN, funds need to be locked in payment channels on the Bitcoin blockchain (Layer-1) ... More
Rheology of dense granular flows for elongated particlesOct 18 2017We study the rheology of dense granular flows for frictionless spherocylinders by means of 3D numerical simulations. As in the case of spherical particles, the effective friction $\mu$ is an increasing function of the inertial number $I$, and we systematically ... More
On nearly Kaehler geometryOct 05 2001We consider complete nearly K\"ahler manifolds with the canonical Hermitian connection. We prove some metric properties of strict nearly K\"ahler manifolds and give a sufficient condition for the reducibility of the canonical Hermitian connection. A holonomic ... More
Rainbow Ramsey problems for the Boolean latticeSep 23 2018We address the following rainbow Ramsey problem: For posets $P,Q$ what is the smallest number $n$ such that any coloring of the elements of the Boolean lattice $B_n$ either admits a monochromatic copy of $P$ or a rainbow copy of $Q$. We consider both ... More
Topological Analysis of Bitcoin's Lightning NetworkJan 15 2019Jan 16 2019Bitcoin's Lightning Network (LN) is a scalability solution for Bitcoin allowing transactions to be issued with negligible fees and settled instantly at scale. In order to use LN, funds need to be locked in payment channels on the Bitcoin blockchain (Layer-1) ... More
Infinite combinatorics plain and simpleMay 17 2017Feb 05 2018We explore a general method based on trees of elementary submodels in order to present highly simplified proofs to numerous results in infinite combinatorics. While countable elementary submodels have been employed in such settings already, we significantly ... More
Efficiency analysis of simple perturbed pairwise comparison matricesMay 26 2015May 11 2016Efficiency, the basic concept of multi-objective optimization is investigated for the class of pairwise comparison matrices. A weight vector is called efficient if no alternative weight vector exists such that every pairwise ratio of the latter's components ... More
Computational Enumeration of Independent Generating Sets of Finite Symmetric GroupsFeb 12 2016Mar 20 2016We developed computer algebra tools for enumerating conjugacy classes of independent subsets and generating sets of symmetric groups up to $n=7$, and carried out an initial analysis of the obtained results.
The Transit Light Source Effect II: The Impact of Stellar Heterogeneity on Transmission Spectra of Planets Orbiting Broadly Sun-like StarsDec 14 2018Transmission spectra probe exoplanetary atmospheres, but they can also be strongly affected by heterogeneities in host star photospheres through the transit light source effect. Here we build upon our recent study of the effects of unocculted spots and ... More
Towards matching user mobility traces in large-scale datasetsSep 18 2017Aug 13 2018The problem of unicity and reidentifiability of records in large-scale databases has been studied in different contexts and approaches, with focus on preserving privacy or matching records from different data sources. With an increasing number of service ... More
Robust regression for mixed Poisson-Gaussian modelNov 23 2016May 17 2017This paper focuses on efficient computational approaches to compute approximate solutions of a linear inverse problem that is contaminated with mixed Poisson--Gaussian noise, and when there are additional outliers in the measured data. The Poisson--Gaussian ... More
Hermitian codes from higher degree placesJun 20 2012Matthews and Michel investigated the minimum distances in certain algebraic-geometry codes arising from a higher degree place $P$. In terms of the Weierstrass gap sequence at $P$, they proved a bound that gives an improvement on the designed minimum distance. ... More
Nuclear properties of loop extensionsMay 13 2015Feb 15 2019The objectives of this paper is to give a systematic investigation of extension theory of loops. A loop extension is (left, right or middle) nuclear, if the kernel of the extension consists of elements associating (from left, right or middle) with all ... More
Schreier decomposition of loopsMay 13 2015The aims of this paper are to find algebraic characterizations of Schreier loops and explore the limits of the non-associative generalization of the theory of Schreier extensions. A loop can have Schreier decomposition with respect to a normal subgroup ... More
Nuclear properties of loop extensionsMay 13 2015Apr 21 2019The objectives of this paper is to give a systematic investigation of extension theory of loops. A loop extension is (left, right or middle) nuclear, if the kernel of the extension consists of elements associating (from left, right or middle) with all ... More
On the complexity of classes of uncountable structures: trees on $\aleph_1$Jun 03 2019We analyse the complexity of the class of (special) Aronszajn, Suslin and Kurepa trees in the projective hierarchy of the higher Baire-space $\omega_1^{\omega_1}$. First, we will show that none of these classes have the Baire property (unless they are ... More
Testing and improving shear viscous phase space correction modelsJul 04 2017Comparison of hydrodynamic calculations with experimental data inevitably requires a model for converting the fluid to particles. In this work, nonlinear $2\to 2$ kinetic theory is used to assess the overall accuracy of various shear viscous fluid-to-particle ... More
Biclique coverings, rectifier networks and the cost of $\varepsilon$-removalMay 30 2014We relate two complexity notions of bipartite graphs: the minimal weight biclique covering number $\mathrm{Cov}(G)$ and the minimal rectifier network size $\mathrm{Rect}(G)$ of a bipartite graph $G$. We show that there exist graphs with $\mathrm{Cov}(G)\geq ... More
Patterns, transitions and the role of leaders in the collective dynamics of a simple robotic flockFeb 03 2012We have developed an experimental setup of very simple self-propelled robots to observe collective motion emerging as a result of inelastic collisions only. A circular pool and commercial RC boats were the basis of our first setup, where we demonstrated ... More
On the feasibility to study inverse proximity effect in a single S/F bilayer by Polarized Neutron ReflectometryJun 10 2013Jun 11 2013Here we report on a feasibility study aiming to explore the potential of Polarized Neutron Reflectometry (PNR) for detecting the inverse proximity effect in a single superconducting/ferromagnetic bilayer. Experiments, conducted on the V(40nm)/Fe(1nm) ... More
Light curve and spectral evolution of the Type IIb SN 2011fuJan 28 2013We present the low-resolution spectroscopic and UBVRI broad-band photometric investigations of the Type IIb supernova 2011fu, discovered in UGC 01626. The photometric follow-up of this event has been initiated a few days after the explosion and covers ... More
Efficiency analysis of double perturbed pairwise comparison matricesFeb 23 2016Efficiency is a core concept of multi-objective optimization problems and multi-attribute decision making. In the case of pairwise comparison matrices a weight vector is called efficient if the approximations of the elements of the pairwise comparison ... More
Deformations of Nearly Kähler StructuresNov 08 2006Feb 16 2007We study the space of nearly K\"{a}hler structures on compact 6-dimensional manifolds. In particular, we prove that the space of infinitesimal deformations of a strictly nearly K\"{a}hler structure (with scalar curvature scal) modulo the group of diffeomorphisms, ... More
Frequencies and resonances around $L_4$ in the elliptic restricted three-body problemJun 05 2014The stability of the Lagrangian point $L_4$ is investigated in the elliptic restricted three-body problem by using Floquet's theory. Stable and unstable domains are determined in the parameter plane of the mass parameter and the eccentricity by computing ... More
Micro-Faraday cup matrix detector for ion beam measurements in fusion plasmasMar 06 2019Atomic Beam Probe (ABP) is an extension of the routinely used Beam Emission Spectroscopy (BES) diagnostic for plasma edge current fluctuation measurement at magnetically confined plasmas. Beam atoms ionized by the plasma are directed to a curved trajectory ... More
Far-from-constant mean curvature solutions of Einstein's constraint equations with positive Yamabe metricsFeb 07 2008Apr 12 2008In this article we develop some new existence results for the Einstein constraint equations using the Lichnerowicz-York conformal rescaling method. The mean extrinsic curvature is taken to be an arbitrary smooth function without restrictions on the size ... More
Simple solutions of fireball hydrodynamics for rotating and expanding triaxial ellipsoids and final state observablesJun 29 2016We present a class of analytic solutions of non-relativistic fireball hydrodynamics for a fairly general class of equation of state. The presented solution describes the expansion of a triaxial ellipsoid that rotates around one of the principal axes. ... More
Simple solutions of fireball hydrodynamics for rotating and expanding triaxial ellipsoids and final state observablesJun 29 2016Nov 16 2016We present a class of analytic solutions of non-relativistic fireball hydrodynamics for a fairly general class of equation of state. The presented solution describes the expansion of a triaxial ellipsoid that rotates around one of the principal axes. ... More
The mass of asymptotically anti-de Sitter space-timesNov 29 2000Oct 04 2001We give a definition of mass for spacelike hypersurfaces in space-times with metrics which are asymptotic to the anti-de Sitter one, or to a class of generalizations thereof. We present the results of gr-qc/0110014 which show that our definition provides ... More
A new family of exact and rotating solutions of fireball hydrodynamicsSep 17 2013Mar 21 2014A new class of analytic, exact, rotating, self-similar and surprisingly simple solutions of non-relativistic hydrodynamics are presented for a three-dimensionally expanding, spheroidally symmetric fireball. These results generalize earlier, non-rotating ... More
Simple solutions of fireball hydrodynamics for rotating and expanding triaxial ellipsoids and final state observablesJun 29 2016Jan 31 2017We present a class of analytic solutions of non-relativistic fireball hydrodynamics for a fairly general class of equation of state. The presented solution describes the expansion of a triaxial ellipsoid that rotates around one of the principal axes. ... More
Finsler manifolds with non-Riemannian holonomyApr 02 2009Jan 15 2010The aim of this paper is to show that holonomy properties of Finsler manifolds can be very different from those of Riemannian manifolds. We prove that the holonomy group of a positive definite non-Riemannian Finsler manifold of non-zero constant curvature ... More
Tangent Lie algebras to the holonomy group of a Finsler manifoldDec 01 2012Our goal in this paper is to make an attempt to find the largest Lie algebra of vector fields on the indicatrix such that all its elements are tangent to the holonomy group of a Finsler manifold. First, we introduce the notion of the curvature algebra, ... More
Projectively flat Finsler manifolds with infinite dimensional holonomyFeb 05 2012Recently, we developed a method for the study of holonomy properties of non-Riemannian Finsler manifolds and obtained that the holonomy group can not be a compact Lie group, if the Finsler manifold of dimension $> 2$ has non-zero constant flag curvature. ... More
The mass of spacelike hypersurfaces in asymptotically anti-de Sitter space-timesOct 02 2001Jan 18 2002We give a Hamiltonian definition of mass for spacelike hypersurfaces in space-times with metrics which are asymptotic to the anti-de Sitter one, or to a class of generalizations thereof. We show that our definition provides a geometric invariant for a ... More
Multi-boson correlations using wave-packets IISep 24 2007We investigate the analytically solvable pion-laser model, and its generalization to arbitrary multiplicity distributions. Although this kind of extension of the model is possible, the pion laser model in its original form is unique: it is the only model ... More
Finsler 2-manifolds whose holonomy group is the diffeomorphism group of the circleOct 25 2012In this paper we show that the topological closure of the holonomy group of a certain class of projectively flat Finsler 2-manifolds of constant curvature is maximal, that is isomorphic to the connected component of the diffeomorphism group of the circle. ... More
Finsler spaces with infinite dimensional holonomy groupDec 02 2010Our paper is devoted to the study of the holonomy groups of Finsler surfaces using the methods of infinite dimensional Lie theory. The notion of infinitesimal holonomy algebra will be introduced, by the smallest Lie algebra of vector fields on an indicatrix, ... More
HIJING++, a Heavy Ion Jet INteraction Generator for the High-luminosity Era of the LHC and BeyondNov 06 2018HIJING++ (Heavy Ion Jet INteraction Generator) is the successor of the widely used original HIJING, developed almost three decades ago. While the old versions (1.x and 2.x) were written in FORTRAN, HIJING++ was completely rewritten in C++. During the ... More
Bruck decomposition for endomorphisms of quasigroupsFeb 06 2009Apr 30 2009In the year 1944 R. H. Bruck has described a very general construction method which he called the extension of a set by a quasigroup. We use it to construct a class of examples for LF-quasigroups in which the image of the map $e(x)=x\backslash x$ is a ... More
Characterization of projectively flat Finsler manifolds of constant curvature with finite dimensional holonomy groupApr 05 2013Apr 12 2013In this paper we prove that the holonomy group of a simply connected locally projectively flat Finsler manifold of constant curvature is a finite dimensional Lie group if and only if it is flat or it is Riemannian.
An analytic hydrodynamical model of rotating 3D expansion in heavy-ion collisionsDec 02 2015A new exact and analytic solution of non-relativistic fireball hydrodynamics is presented. It describes an expanding triaxial ellipsoid that rotates around one of its principal axes. The observables are calculated using simple analytic formulas. Azimuthal ... More
A Framework for ETH-Tight Algorithms and Lower Bounds in Geometric Intersection GraphsMar 28 2018Apr 13 2018We give an algorithmic and lower-bound framework that facilitates the construction of subexponential algorithms and matching conditional complexity bounds. It can be applied to a wide range of geometric intersection graphs (intersections of similarly ... More
The open dihypergraph dichotomy and the second level of the Borel hierarchyMar 08 2018We show that several dichotomy theorems concerning the second level of the Borel hierarchy are special cases of the $\aleph_0$-dimensional generalization of the open graph dichotomy, which itself follows from the usual proof(s) of the perfect set theorem. ... More
Towers and gaps at uncountable cardinalsJun 03 2019Our goal is to study the pseudo-intersection and tower numbers on uncountable regular cardinals, whether these two cardinal characteristics are necessarily equal, and related problems on the existence of gaps. First, we prove that either $\mathfrak p(\kappa)=\mathfrak ... More
Persistent collective trend in stock marketsMay 03 2010Empirical evidence is given for a significant difference in the collective trend of the share prices during the stock index rising and falling periods. Data on the Dow Jones Industrial Average and its stock components are studied between 1991 and 2008. ... More
Resonant inelastic x-ray scattering as a probe of band structure effects in cupratesAug 26 2015Dec 12 2016We analyze within quasi-particle theory a recent resonant inelastic x-ray scattering (RIXS) experiment on $\mathrm{YBa_2Cu_3O_{6+x}}$ with the incoming photon energy detuned at several values from the resonance maximum [Minola et al., Phys. Rev. Lett. ... More
Algebraic double cut and join -- A group-theoretic approach to the operator on multichromosomal genomesSep 25 2014Establishing a distance between genomes is a significant problem in computational genomics, because its solution can be used to establish evolutionary relationships including phylogeny. The "double cut and join" (DCJ) model of chromosomal rearrangement ... More
Lambda_msbar from the static potential for QCD with n_f=2 dynamical quark flavorsOct 31 2011Nov 21 2011We determine Lambda_msbar for QCD with n_f=2 dynamical quark flavors by fitting the Q-Q-bar static potential known analytically in the perturbative regime up to terms of O(alpha_s^4) and ~alpha_s^4 ln(alpha_s) to corresponding results obtained from lattice ... More
Accelerating Solutions of Perfect Fluid Hydrodynamics for Initial Energy Density and Life-Time Measurements in Heavy Ion CollisionsFeb 13 2007Apr 17 2007A new class of accelerating, exact, explicit and simple solutions of relativistic hydrodynamics is presented. Since these new solutions yield a finite rapidity distribution, they lead to an advanced estimate of the initial energy density and life-time ... More
Detailed description of accelerating, simple solutions of relativistic perfect fluid hydrodynamicsSep 24 2007In this paper we describe in full details a new family of recently found exact solutions of relativistic, perfect fluid dynamics. With an ansatz, which generalizes the well-known Hwa-Bjorken solution, we obtain a wide class of new exact, explicit and ... More
Anomalous diffusion of pions at RHICFeb 02 2007Apr 12 2007After pointing out the difference between normal and anomalous diffusion, we consider a hadron resonance cascade (HRC) model simulation for particle emission at RHIC and point out, that rescattering in an expanding hadron resonance gas leads to a heavy ... More
Similar final states from different initial states using new exact solutions of relativistic hydrodynamicsOct 01 2007Nov 22 2007We present exact, analytic and simple solutions of relativistic perfect fluid hydrodynamics. The solutions allow us to calculate the rapidity distribution of the particles produced at the freeze-out, and fit them to the measured rapidity distribution ... More
A New Family of Simple Solutions of Perfect Fluid HydrodynamicsMay 25 2006Jun 29 2007A new class of accelerating, exact and explicit solutions of relativistic hydrodynamics is found - more than 50 years after the previous similar result, the Landau-Khalatnikov solution. Surprisingly, the new solutions have a simple form, that generalizes ... More
New exact solutions of relativistic hydrodynamicsMay 11 2008A new class of simple and exact solutions of relativistic hydrodynamics is presented, and the consequences are explored in data analysis. The effects of longitudinal work and acceleration are taken into account in an advanced estimate of the initial energy ... More
Numerical reconstruction of pulsatile blood flow from 4D computer tomography angiography dataNov 25 2015We present a novel numerical algorithm developed to reconstuct pulsatile blood flow from ECG-gated CT angiography data. A block-based optimization method was constructed to solve the inverse problem corresponding to the Riccati-type ordinary differential ... More
PHENIX results on Bose-Einstein correlation functionsFeb 15 2016Measurement of Bose-Einstein or HBT correlations of identified charged particles provide insight into the space-time structure of particle emitting sources in heavy-ion collisions. In this paper we present the latest results from the RHIC PHENIX experiment ... More
Applications of an intersection formula to dual conesApr 03 2017Oct 19 2017We give a succinct proof of a duality theorem obtained by R\'ev\'esz in 1991 which concerns extremal quantities related to trigonomertic polynomials. The key tool of our new proof is an intersection formula on dual cones in real Banach spaces. We show ... More
Fundamental oscillation modes and thermal relaxation in young neutron starsAug 07 2019We present a novel survey of the radial oscillation modes and relaxation of neutron stars for various types of nuclear-theory-based EOS of cold neutron-star matter. This study complements our earlier qualitative study of the effect of viscosity and thermal ... More
Complete intersection quiver settings with one dimensional verticesMay 16 2011Jul 17 2011We describe the class of quiver settings with one dimensional vertices whose semi-simple representations are parametrized by a complete intersection variety. We show that these quivers can be reduced to a one vertex quiver with some combinatorial reduction ... More
Permeability and conductivity of platelet-reinforced membranes and compositesAug 08 2001We present large scale simulations of the diffusion constant $D$ of a random composite consisting of aligned platelets with aspect ratio $a/b>>1$ in a matrix (with diffusion constant $D_0$) and find that $D/D_0 = 1/(1+ c_1 x + c_2 x^2)$, where $x= a v_f/b$ ... More