Results for "Alfred Zimmermann"

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The Ring of Polynomial Functors of Prime DegreeApr 17 2013Aug 15 2013Let $\hat\Z_p$ be the ring of $p$-adic integers. We prove in the present paper that the category of polynomial functors from finitely generated free abelian groups to $\hat \Z_p$-modules of degree at most $p$ is equivalent to the category of finitely ... More
On the use of Külshammer type invariants in representation theoryOct 29 2010Since 2005 a new powerful invariant of an algebra emerged using earlier work of Horv\'ath, H\'ethelyi, K\"ulshammer and Murray. The authors studied Morita invariance of a sequence of ideals of the centre of a finite dimensional algebra over a field of ... More
Logarithmic Sobolev inequalities for mollified compactly supported measuresNov 05 2014We show that the convolution of a compactly supported measure on $\mathbb{R}$ with a Gaussian measure satisfies a logarithmic Sobolev inequality (LSI). We use this result to give a new proof of a classical result in random matrix theory that states that, ... More
A matrix-algebraic algorithm for the Riemannian logarithm on the Stiefel manifold under the canonical metricApr 18 2016Mar 17 2017We derive a numerical algorithm for evaluating the Riemannian logarithm on the Stiefel manifold with respect to the canonical metric. In contrast to the existing optimization-based approach, we work from a purely matrix-algebraic perspective. Moreover, ... More
The Abelianisation of the real Cremona groupOct 29 2015Apr 15 2016We present the Abelianisation of the birational transformations of $\mathbb{P}_{\mathbb{R}}^2$. Its kernel is equal to the normal subgroup generated by $\mathrm{PGL}_3(\mathbb{R})$, and contains all elements of degree $\leq4$. The description of the quotient ... More
Remarks on a Categorical Definition of Degeneration in Triangulated CategoriesJun 08 2015This work reports on joint research with Manuel Saorin. For an algebra A over an algebraically closed field k the set of A-module structures on k d forms an affine algebraic variety. The general linear group Gl d (k) acts on this variety and isomorphism ... More
A feature construction framework based on outlier detection and discriminative pattern miningJul 17 2014No matter the expressive power and sophistication of supervised learning algorithms, their effectiveness is restricted by the features describing the data. This is not a new insight in ML and many methods for feature selection, transformation, and construction ... More
K{ü}lshammer ideals of algebras of quaternion typeMay 25 2016May 31 2017For a symmetric algebra A over a field K of characteristic p > 0 K{\"u}lshammer constructed a descending sequence of ideals of the centre of A. If K is perfect this sequence was shown to be an invariant under derived equivalence and for algebraically ... More
The ALICE analysis train systemFeb 23 2015In the ALICE experiment hundreds of users are analyzing big datasets on a Grid system. High throughput and short turn-around times are achieved by a centralized system called the LEGO trains. This system combines analysis from different users in so-called ... More
Külshammer ideals of algebras of quaternion typeMay 25 2016May 27 2016For a symmetric algebra A over a field K of characteristic p \textgreater{} 0 K{\"u}lshammer constructed a descending sequence of ideals of the centre of A. If K is perfect this sequence was shown to be an invariant under derived equivalence and for algebraically ... More
Hermite Interpolation and data processing errors on Riemannian matrix manifoldsAug 16 2019The main contribution of this paper is twofold: On the one hand, a general framework for performing Hermite interpolation on Riemannian manifolds is presented. The method is applicable, if algorithms for the associated Riemannian exponential and logarithm ... More
Simple transitive $2$-representations of some $2$-categories of projective functorsMay 02 2017We show that every simple transitive $2$-representation of the $2$-category of projective functors for a certain quotient of the quadratic dual of the preprojective algebra associated with a tree is equivalent to a cell $2$-representation.
Production of strange particles in charged jets in p--Pb and Pb--Pb collisions measured with ALICE at the LHCFeb 04 2015Studies of jet production can provide information about the properties of the hot and dense strongly interacting matter created in ultra-relativistic heavy-ion collisions. Specifically, measurement of strange particles in jets may clarify the role of ... More
The theorem that was none - I. Early historyApr 30 2015The early history of the Vogt-Russell theorem is retraced following its route starting at the realization of a correlation between mass and luminosity of binary and pulsating stars, through the embossing of this observation into a theorem, and finally ... More
An Attempt to Pin Down the Instability Domain of Long-Period VariablesJul 21 1999The period-luminosity relation of Miras and semiregular variables in the Large Magellanic Cloud and in the Galaxy is used to locate their instability domain in the Hertzsprung-Russell diagram. We take advantage of the considerable width in luminosity ... More
The integrated model of cAMP-dependent DNA expression reveals an inverse relationship between cancer and neurodegenerationJun 03 2016The model for cAMP-dependent synaptic plasticity relates the characterization of a noradrenaline-stimulated adenylyl cyclase with DNA unzipping. Specific proteins condition cAMP insertion in specific sites of the DNA structure to direct cellular and synaptic ... More
Multivariate Stirling Polynomials of the first and second kindNov 20 2013Jul 21 2015Two doubly indexed families of homogeneous and isobaric polynomials in several indeterminates are considered: the (partial) exponential Bell polynomials $B_{n,k}$ and a new family $S_{n,k}$ such that $X_1^{-(2n-1)}S_{n,k}$ and $B_{n,k}$ obey an inversion ... More
Non-commutative Krull monoids: A divisor theoretic approach and their arithmeticAug 21 2012A (not necessarily commutative) Krull monoid---as introduced by Wauters---is defined as a completely integrally closed monoid satisfying the ascending chain condition on divisorial two-sided ideals. We study the structure of these Krull monoids, both ... More
Microservices Migration in Industry: Intentions, Strategies, and ChallengesJun 11 2019To remain competitive in a fast changing environment, many companies started to migrate their legacy applications towards a Microservices architecture. Such extensive migration processes require careful planning and consideration of implications and challenges ... More
10 Years of wire excitation experiments in the CERN SPSOct 14 2014This paper reviews the set-up, experimental studies, and beam observations with one or two prototype long-range beam-beam 'wire' compensators in the CERN SPS from 2002 to 2012.
Wages of wins: could an amateur make money from match outcome predictions?Feb 17 2017Evaluating the accuracies of models for match outcome predictions is nice and well but in the end the real proof is in the money to be made by betting. To evaluate the question whether the models developed by us could be used easily to make money via ... More
A Noether-Deuring theorem for derived categoriesDec 15 2011Jan 13 2012We prove a Noether-Deuring theorem for the derived category of bounded complexes of modules over a Noetherian algebra.
Simple transitive $2$-representations of Soergel bimodules in type $B_2$Sep 04 2015Jun 17 2016We prove that every simple transitive $2$-representation of the fiat $2$-category of Soergel bimodules (over the coinvariant algebra) in type $B_2$ is equivalent to a cell $2$-representation. We also describe some general properties of the $2$-category ... More
Games with Costs and DelaysJan 09 2017Apr 20 2017We demonstrate the usefulness of adding delay to infinite games with quantitative winning conditions. In a delay game, one of the players may delay her moves to obtain a lookahead on her opponent's moves. We show that determining the winner of delay games ... More
Parameterized Linear Temporal Logics Meet Costs: Still not Costlier than LTLSep 24 2015We continue the investigation of parameterized extensions of Linear Temporal Logic (LTL) that retain the attractive algorithmic properties of LTL: a polynomial space model checking algorithm and a doubly-exponential time algorithm for solving games. Alur ... More
Fine Hochschild invariants of derived categories for symmetric algebrasAug 29 2006Let $A$ be a symmetric $k$-algebra over a perfect field $k$. K\"ulshammer defined for any integer $n$ a mapping $\zeta\_n$ on the degree 0 Hochschild cohomology and a mapping $\kappa\_n$ on the degree 0 Hochschild homology of $A$ as adjoint mappings of ... More
A matrix-algebraic algorithm for the Riemannian logarithm on the Stiefel manifoldApr 18 2016May 09 2016We derive a numerical algorithm for evaluating the Riemannian logarithm on the Stiefel manifold with respect to the canonical metric. In contrast to the optimization-based approach known from the literature, we work from a purely matrix-algebraic perspective. ... More
A closed-form update for orthogonal matrix decompositions under arbitrary rank-one modificationsNov 22 2017Jun 08 2018We consider rank-one adaptations $X_{new} = X+ab^T$ of a given matrix $X\in \mathbb{R}^{n\times p}$ with known matrix factorization $X = UW$, where $U\in\mathbb{R}^{n\times p}$ is column-orthogonal, i.e. $U^TU=I$. Arguably the most important methods that ... More
Stability of a colocated finite volume scheme for the incompressible Navier-Stokes equationsApr 05 2007We introduce a finite volume scheme for the two-dimensional incompressible Navier-Stokes equations. We use a triangular mesh. The unknowns for the velocity and pressure are both piecewise constant (colocated scheme). We use a projection (fractional-step) ... More
Stability of a finite volume scheme for the incompressible fluidsApr 05 2007Nov 20 2007We introduce a finite volume scheme for the two-dimensional incompressible Navier-Stokes equations. We use a triangular mesh. The unknowns for the velocity and pressure are respectively piecewise constant and affine. We use a projection method to deal ... More
Multi-Photon Interference and MetrologyOct 10 2017Oct 15 2017Recently, Motes et al. proposed in Phys. Rev. Lett. 114, 170802 (2015) a linear optics interferometer with N identical single photon input states as a tool for sub-shot-noise phase estimation which does not require NOON states sources. This thesis investigates ... More
Changement de base pour les foncteurs TorMar 14 2003We give in this paper an isomorphism theorem between derived functors over categories of modules.There is a nice class of categories that gives examples in which this theorem applies for a special construction. This leads us to a new interpretation of ... More
From Monolith to Microservices: A Classification of Refactoring ApproachesJul 26 2018Jan 24 2019While the recently emerged Microservices architectural style is widely discussed in literature, it is difficult to find clear guidance on the process of refactoring legacy applications. The importance of the topic is underpinned by high costs and effort ... More
Assuring the Evolvability of Microservices: Insights into Industry Practices and ChallengesJun 12 2019While Microservices promise several beneficial characteristics for sustainable long-term software evolution, little empirical research covers what concrete activities industry applies for the evolvability assurance of Microservices and how technical debt ... More
Ky Fan inequalities for bivariate meansJan 02 2019Mar 03 2019In this note we give sufficient conditions for bivariate, homogeneous, symmetric means $M$ and $N$ to satisfy Ky Fan inequalities $$\frac{M}{M'}<\frac{N}{N'}\qquad\text{ and }\quad \frac{1}{M}-\frac{1}{M'}<\frac{1}{N}-\frac{1}{N'}.$$
A hypercyclicity criterion for non-metrizable topological vector spacesApr 13 2018We provide a sufficient condition for an operator $T$ on a non-metrizable and sequentially separable topological vector space $X$ to be sequentially hypercyclic. This condition is applied to some particular examples, namely, a composition operator on ... More
Sets of LengthsSep 24 2015Aug 10 2016Oftentimes the elements of a ring or semigroup $H$ can be written as finite products of irreducible elements, say $a=u_1 \cdot \ldots \cdot u_k = v_1 \cdot \ldots \cdot v_{\ell}$, where the number of irreducible factors is distinct. The set $\mathsf L ... More
The square lattice Ising model on the rectangle I: Finite systemsSep 07 2016Oct 07 2016The partition function of the square lattice Ising model on the rectangle is calculated exactly for arbitrary system size $L\times M$ and temperature. We start with the dimer method of Kasteleyn, McCoy & Wu, construct a highly symmetric block transfer ... More
Non-equilibrium phase transition in an exactly solvable driven Ising model with frictionSep 02 2009Nov 04 2009A driven Ising model with friction due to magnetic correlations has recently been proposed by Kadau et al. (Phys. Rev. Lett. 101, 137205 (2008)). The non-equilibrium phase transition present in this system is investigated in detail using analytical methods ... More
Neutrino Counter Nuclear WeaponMay 26 2008Jun 25 2013Radiations produced by neutrino-antineutrino annihilation at the Z0 pole can be used to heat up the primary stage of a thermonuclear warhead and can in principle detonate the device remotely. Neutrino-antineutrino annihilation can also be used as a tactical ... More
On the Symmetry of Universal Finite-Size Scaling Functions in Anisotropic SystemsFeb 08 2002In this work a symmetry of universal finite-size scaling functions under a certain anisotropic scale transformation is postulated. This transformation connects the properties of a finite two-dimensional system at criticality with generalized aspect ratio ... More
The dynamics of H-bonds of the hydration shells of ions, ATPase and NE-activated adenylyl cyclase on the coupling of energy and signal transductionJul 17 2012Glycerol titration distinguished from free water the local hydration shell involved in ATPase transition from active to inactive, with cooperativity for water n=16. Rat brain cortex: NE-stimulated and its basal AC in the absence of free Mg2+, allows a ... More
Potential dangers when phase shifts are used as a link between experiment and QCDNov 22 2012Luscher has shown that in single channel problem (elastic region below first inelastic threshold) there exists a direct link between the discrete value of the energy in a finite QCD volume and the scattering phase shift at the same energy. However, when ... More
Helium Ignition in the Cores of Low-Mass StarsAug 19 2012In stars with $M_\ast \lesssim 2 M_\odot$, nuclear burning of helium starts under degenerate conditions and, depending on the efficiency of neutrino cooling, more or less off-center. The behavior of the centers of low-mass stars undergoing core helium ... More
The assay of the hydration shell dynamics on the turnover of the active site of CF1-ATPaseJul 07 2016Previous kinetic models had assumed that the reaction medium was reacting at random and without a turnover associated to thermodynamics exchanges, with a rigid active site on the enzyme. The experimental studies show that coupling factor 1 (CF1) from ... More
The square lattice Ising model on the rectangle II: Finite-size scaling limitJan 30 2017Apr 27 2017Based on the results published recently [J. Phys. A: Math. Theor. 50, 065201 (2017)], the universal finite-size contributions to the free energy of the square lattice Ising model on the $L\times M$ rectangle, with open boundary conditions in both directions, ... More
The coupling of thermodynamics with the organizational water-protein intra-dynamics driven by the H-bonds dissipative potential of cluster waterMar 27 2013The Red cell-Hb-CSF functions as a sensor adapting response to Hb heterotropic equilibriums. At the lungs O2 and Mg2+, each one increasing affinity for the other stabilize the relax (R) form [(O2)4Hb(Mg)2].(H2O)R. At tissue level, the inclusion of H+ ... More
The Thermal Pulses of Very-Low-Mass StarsMar 26 2013Very-low-mass stars can develop secularly unstable hydrogen-burning shells late in their life. Since the thermal pulses that go along are driven at the bottoms of very shallow envelopes, the stars' luminosities and effective temperatures react strongly ... More
Reviving old, almost lost knowledge on T and K matrix poles and a link to the contemporary QCD spectrumFeb 14 2012The old knowledge about interrelation among T-matrix, K-matrix and bare poles is summarized and put into modern perspective.
Characterization of the norepinephrine-activation of adenylate cyclase suggests a role in memory affirmation pathways. Overexposure to epinephrine inactivates adenylate-cyclase,a causal pathway for stress-pathologiesDec 15 2010Incubation with noradrenaline (norepinephrine) of isolated membranes of rat's brain corpus striatum and cortex, showed that ionic-magnesium (Mg2+) is required for the neurotransmitter activatory response of Adenylate Cyclase [ATP pyrophosphate-lyase (cyclizing), ... More
The theorem that was none - II. The profound 70sDec 31 2018This second pedagogical installment on the history of the Vogt-Russell theorem focuses on research in the 1970s on the existence and uniqueness of star models. An appendix presents stellar evolution models, computed with the MESA code, in different approximations ... More
Mitigating performance limitations of single beam-pipe circular e+e- collidersJun 02 2015Renewed interest in circular e+e- colliders has spurred designs of single beam-pipe machines, like the CEPC in China, and double beam pipe ones, such as the FCC-ee effort at CERN. Single beam-pipe designs profit from lower costs but are limited by the ... More
A Multi-level Blocking Distinct Degree Factorization AlgorithmOct 24 2007We give a new algorithm for performing the distinct-degree factorization of a polynomial P(x) over GF(2), using a multi-level blocking strategy. The coarsest level of blocking replaces GCD computations by multiplications, as suggested by Pollard (1975), ... More
On Jordan type bounds for finite groups of diffeomorphisms of 3-manifolds and Euclidean spacesFeb 07 2014By a classical result of Jordan, each finite subgroup G of a complex linear group GL_n(C) has an abelian subgroup whose index in G is bounded by a constant depending only on n. We consider the problem if this remains true for finite subgroups G of the ... More
Particles held by springs in a linear shear flow exhibit oscillatory motionApr 26 2006Jun 01 2006The dynamics of small spheres, which are held by linear springs in a low Reynolds number shear flow at neighboring locations is investigated. The flow elongates the beads and the interplay of the shear gradient with the nonlinear behavior of the hydrodynamic ... More
On minimal actions of finite simple groups on homology spheres and Euclidean spacesDec 05 2008Sep 03 2010We consider the following problem: for which classes of finite groups, and in particular finite simple groups, does the minimal dimension of a faithful, smooth action on a homology sphere coincide with the minimal dimension of a faithful, linear action ... More
Benchmarking electron-cloud simulations and pressure measurements at the LHCJun 24 2013During the beam commissioning of the Large Hadron Collider (LHC) with 150, 75, 50 and 25-ns bunch spacing, important electron-cloud effects, like pressure rise, cryogenic heat load, beam instabilities or emittance growth, were observed. A method has been ... More
Coherent potential approximation for spatially correlated disorderApr 25 2009Oct 15 2009The coherent potential approximation (CPA) is extended to describe satisfactorily the motion of particles in a random potential which is spatially correlated and smoothly varying. In contrast to existing cluster-CPA methods, the present scheme preserves ... More
Electron-Phonon Interaction in Embedded Semiconductor NanostructuresOct 15 2006The modification of acoustic phonons in semiconductor nanostructures embedded in a host crystal is investigated including corrections due to strain within continuum elasticity theory. Effective elastic constants are calculated employing {\em ab initio} ... More
Optical absorption in quantum dots: Coupling to longitudinal optical phonons treated exactlyJun 16 2005Jan 31 2006Optical transitions in a semiconductor quantum dot are theoretically investigated, with emphasis on the coupling to longitudinal optical phonons, and including excitonic effects. When limiting to a finite number of $m$ electron and $n$ hole levels in ... More
Decentralization as Organizing Principle of Emergent Urban StructuresMar 07 2002With a view to the ongoing Bologna project ( general organizing principles of emergent structures in social systems are being discussed with a view to the meaning of decentralization. It is proposed to introduce decentralization ... More
Non-circular semiconductor nanorings of type I and II: Emission kinetics in the exciton Aharonov-Bohm effectSep 17 2007Transition energies and oscillator strengths of excitons in dependence on magnetic field are investigated in type I and II semiconductor nanorings. A slight deviation from circular (concentric) shape of the type II nanoring gives a better observability ... More
Near-field spectra of quantum well excitons with non-Markovian phonon scatteringDec 20 2005Apr 03 2006The excitonic absorption spectrum for a disordered quantum well in presence of exciton-acoustic phonon interaction is treated beyond the Markov approximation. Realistic disorder exciton states are taken from a microscopic simulation, and the deformation ... More
Random Matrices with Log-Range Correlations, and Log-Sobolev InequalitiesMay 11 2014Dec 06 2016Let $X_N$ be a symmetric $N\times N$ random matrix whose $\sqrt{N}$-scaled centered entries are uniformly square integrable. We prove that if the entries of $X_N$ can be partitioned into independent subsets each of size $o(\log N)$, then the empirical ... More
Representation-tame algebras need not be homologically tameSep 26 2015We show that, also within the class of representation-tame finite dimensional algebras $\Lambda$, the big left finitistic dimension of $\Lambda$ may be strictly larger than the little. In fact, the discrepancies $Findim \Lambda - findim \Lambda$ need ... More
On minimal actions of linear fractional and finite simple groups on homology spheresMay 17 2006Sep 03 2010This paper has been withdrawn since it is superated by the latest version of arXiv:0812.1139 (this is the version which will appear in Rend. Circ. Mat. Palermo; it is a strengthening and elaboration of a paper published in Math. Proc. Camb. Phil. Soc. ... More
Top-stable degenerations of finite dimensional representations IJul 10 2014Given a finite dimensional representation $M$ of a finite dimensional algebra, two hierarchies of degenerations of $M$ are analyzed in the context of their natural orders: the poset of those degenerations of $M$ which share the top $M/JM$ with $M$ - here ... More
Traveling ion channel density waves affected by a conservation lawFeb 15 2006Apr 07 2006A model of mobile, charged ion channels embedded in a biomembrane is investigated. The ion channels fluctuate between an opened and a closed state according to a simple two-state reaction scheme whereas the total number of ion channels is a conserved ... More
An axiomatic approach for degenerations in triangulated categoriesJun 09 2015We generalise Yoshino's definition of a degeneration of two Cohen Macaulay modules to a definition of degeneration between two objects in a triangulated category. We derive some natural properties for the triangulated category and the degeneration under ... More
Generalized Reynolds ideals and derived equivalences for algebras of dihedral and semidihedral typeJul 04 2008Generalized Reynolds ideals are ideals of the center of a symmetric algebra over a field of positive characteristic. They have been shown by the second author to be invariant under derived equivalences. In this paper we determine the generalized Reynolds ... More
Dumbbell transport and deflection in a spatially periodic potentialMar 13 2009We present theoretical results on the deterministic and stochastic motion of a dumbbell carried by a uniform flow through a three-dimensional spatially periodic potential. Depending on parameters like the flow velocity, there are two different kinds of ... More
Counting Quasi-Idempotent Irreducible Integral MatricesJan 13 2017Dec 04 2017Given any polynomial $p$ in $C[X]$, we show that the set of irreducible matrices satisfying $p(A)=0$ is finite. In the specific case $p(X)=X^2-nX$, we count the number of irreducible matrices in this set and analyze the arising sequences and their asymptotics. ... More
A High Luminosity e+e- Collider in the LHC tunnel to study the Higgs BosonDec 12 2011Feb 15 2012We consider the possibility of a 120x120 GeV e+e- ring collider in the LHC tunnel. A luminosity of 10^34/cm2/s can be obtained with a luminosity life time of a few minutes. A high operation efficiency would require two machines: a low emittance collider ... More
On finite simple groups acting on homology spheres with small fixed point setsMay 28 2014A finite nonabelian simple group does not admit a free action on a homology sphere, and the only finite simple group which acts on a homology sphere with at most 0-dimensional fixed point sets ("pseudofree action") is the alternating group A_5 acting ... More
On finite groups acting on a connected sum of 3-manifolds S^2 \times S^1Feb 24 2012Feb 09 2014Let H_g denote the closed 3-manifold obtained as the connected sum of g copies of S^2 times S^1, with free fundamental group of rank g. We prove that, for a finite group G acting on H_g which induces a faithful action on the fundamental group, there is ... More
A classification of maximally symmetric surfaces in the 3-dimensional torusApr 07 2018If a finite group of orientation-preserving diffeomorphisms of the 3-dimensional torus leaves invariant an oriented, closed, embedded surface of genus g>1 and preserves the orientation of the surface, then its order is bounded from above by 12(g-1). In ... More
Comment on "Adv-BNN: Improved Adversarial Defense through Robust Bayesian Neural Network"Jul 01 2019A recent paper by Liu et al. combines the topics of adversarial training and Bayesian Neural Networks (BNN) and suggests that adversarially trained BNNs are more robust against adversarial attacks than their non-Bayesian counterparts. Here, I analyze ... More
Classifying representations by way of GrassmanniansJul 10 2014Let $\Lambda$ be a finite dimensional algebra over an algebraically closed field. Criteria are given which characterize existence of a fine or coarse moduli space classifying, up to isomorphism, the representations of $\Lambda$ with fixed dimension $d$ ... More
Modeling oscillatory Microtubule--PolymerizationOct 07 2002Polymerization of microtubules is ubiquitous in biological cells and under certain conditions it becomes oscillatory in time. Here simple reaction models are analyzed that capture such oscillations as well as the length distribution of microtubules. We ... More
Feasibility Study of Lense-Thirring Precession in LS I +61303Mar 18 2010Very recent analysis of the radio spectral index and high energy observations have shown that the two-peak accretion/ejection microquasar model applies for LSI+61303. The fast variations of the position angle observed with MERLIN and confirmed by consecutive ... More
On topological actions of finite groups on S^3Jun 24 2016Sep 01 2016We consider orientation-preserving actions of a finite group G on the 3-sphere S^3 (and also on Euclidean space R^3). By the geometrization of finite group actions on 3-manifolds, if such an action is smooth then it is conjugate to an orthogonal action, ... More
On upper and lower bounds for finite group actions on bounded surfaces, handlebodies, closed handles and finite graphsApr 22 2016This is a survey on upper and lower bounds for finite group actions on bounded surfaces, 3-dimensional handlebodies and closed handles, handlebodies in arbitrary dimensions and finite graphs (the common feature of these objects is that all have free fundamental ... More
Recent Conceptual Consequences of Loop Quantum Gravity. Part I: Foundational AspectsJul 25 2001Conceptual consequences of recent results in loop quantum gravity are collected and discussed here in view of their implications for a modern philosophy of science which is mainly understood as one that totalizes scientific insight so as to eventually ... More
Computations in Stochastic AcceptorsDec 23 2018Machine learning provides algorithms that can learn from data and make inferences or predictions on data. Stochastic acceptors or probabilistic automata are stochastic automata without output that can model components in machine learning scenarios. In ... More
A hierarchy of parametrizing varieties for representationsJul 10 2014The primary purpose is to introduce and explore projective varieties, $\text{GRASS}_{\bf d}(\Lambda)$, parametrizing the full collection of those modules over a finite dimensional algebra $\Lambda$ which have dimension vector $\bf d$. These varieties ... More
Degenerating $0$ in Triangulated CategoriesJan 28 2019In previous work, based on work of Zwara and Yoshino, we defined and studied degenerations of objects in triangulated categories analogous to degeneration of modules. In triangulated categories it is surprising that the zero object may degenerate. We ... More
Introduction to High-Resolution Inelastic X-Ray ScatteringApr 05 2015May 18 2015This paper reviews non-resonant, meV-resolution inelastic x-ray scattering (IXS), as applied to the measurement of atomic dynamics of crystalline materials. It is designed to be an introductory, though in-depth, look at the field for those who may interested ... More
On Cyclic and Nearly Cyclic Multiagent Interactions in the PlaneJul 16 2009We discuss certain types of cyclic and nearly cyclic interactions among N "point"-agents in the plane, leading to formations of interesting limiting geometric configurations. Cyclic pursuit and local averaging interactions have been analyzed in the context ... More
On Kaluza-Klein spacetime in Einstein-Gauss-Bonnet gravityApr 08 2008Sep 08 2008By considering the product of the usual four dimensional spacetime with two dimensional space of constant curvature, an interesting black hole solution has recently been found for Einstein-Gauss-Bonnet gravity. It turns out that this as well as all others ... More
Detailed analysis of eta production in proton-proton collisionsMay 02 2001The check whether the presently available multiresonance coupled channel analyses can explain the more complex processes is made. The process chosen is a well measured proces of eta production in proton proton collisions.
Crossing the coexistence line at constant magnetizationNov 07 2000Apr 30 2001Using Monte Carlo histogram methods, the microcanonical caloric curve is computed for the Ising model in two and three dimensions with fixed magnetization. Whereas the signatures of a first order phase transition are clearly visible for large systems, ... More
Relativistic calculation of the triton binding energy and its implicationsJul 09 1996First results for the triton binding energy obtained from the relativistic spectator or Gross equation are reported. The Dirac structure of the nucleons is taken into account. Numerical results are presented for a family of realistic OBE models with off-shell ... More
A Clifford Dyadic Superfield from Bilateral Interactions of Geometric Multispin Dirac TheoryNov 09 1993Multivector quantum mechanics utilizes wavefunctions which are Clifford aggregates (e.g. sum of scalar, vector, bivector). This is equivalent to multi- spinors constructed of Dirac matrices, with the representation independent form of the generators geometrically ... More
Microcanonical determination of the order parameter critical exponentOct 04 2001Jul 18 2002A highly efficient Monte Carlo method for the calculation of the density of states of classical spin systems is presented. As an application, we investigate the density of states Omega_N(E,M) of two- and three-dimensional Ising models with N spins as ... More
Resonance Extraction from the SAID AnalysisOct 28 2015Resonances are extracted from a number of energy-dependent and single-energy fits to scattering data. The influence of recent, precise EPECUR data is investigated. Results for the single-energy fits are derived using the L+P method of analysis and are ... More
Exponential Strong Converse for Successive Refinement with Causal Decoder Side InformationJan 05 2019Feb 23 2019We consider the $k$-user successive refinement problem with causal decoder side information and derive an exponential strong converse theorem. The rate-distortion region for the problem can be derived as a straightforward extension of the two-user case ... More
Multimodal Event Detection in Twitter Hashtag NetworksJan 03 2016May 16 2016Event detection in a multimodal Twitter dataset is considered. We treat the hashtags in the dataset as instances with two modes: text and geolocation features. The text feature consists of a bag-of-words representation. The geolocation feature consists ... More
An approximate global solution of Einstein's equations for a rotating two layers starJun 11 2018We obtain an approximate global stationary and axisymmetric solution of Einstein's equations which can be thought as a simple two layers star model: a self-gravitating ball built up by two layers of perfect fluid having different linear equation of state ... More
Sets of Arithmetical Invariants in Transfer Krull MonoidsMay 08 2018Transfer Krull monoids are a recent concept including all commutative Krull domains and also, for example, wide classes of non-commutative Dedekind domains. We show that transfer Krull monoids are fully elastic (i.e., every rational number between $1$ ... More
Minimal relations and catenary degrees in Krull monoidsMar 21 2016Aug 13 2016Let $H$ be a Krull monoid with class group $G$. Then $H$ is factorial if and only if $G$ is trivial. Sets of lengths and sets of catenary degrees are well studied invariants describing the arithmetic of $H$ in the non-factorial case. In this note we focus ... More