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Results for "Hartwig R. Siebner"

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Ergodicity-breaking reveals time optimal economic behavior in humansJun 11 2019Jun 19 2019Ergodicity describes an equivalence between the expectation value and the time average of observables. Applied to human behaviour, ergodic theory reveals how individuals should tolerate risk in different environments. To optimise wealth over time, agents ... More
Self-intersection of the relative dualizing sheaf on modular curves $X_1(N)$Dec 06 2012Let $N$ be an odd and squarefree positive integer divisible by at least two relative prime integers bigger or equal than 4. Our main theorem is an asymptotic formula solely in terms of $N$ for the stable arithmetic self-intersection number of the relative ... More
Ergodicity-breaking reveals time optimal economic behavior in humansJun 11 2019Jun 12 2019Ergodicity describes an equivalence between the expectation value and the time average of observables. Applied to human behaviour, ergodic theory reveals how individuals should tolerate risk in different environments. To optimise wealth over time, agents ... More
Ergodicity-breaking reveals time optimal economic behavior in humansJun 11 2019Ergodicity describes an equivalence between the expectation value and the time average of observables. Applied to human behaviour, ergodic theory reveals how individuals should tolerate risk in different environments. To optimise wealth over time, agents ... More
Classification of twisted generalized Weyl algebras over polynomial ringsMar 28 2019Apr 18 2019Let $R$ be a polynomial ring in $m$ variables over a field of characteristic zero. We classify all rank $n$ twisted generalized Weyl algebras over $R$, up to $\mathbb{Z}^n$-graded isomorphisms, in terms of higher spin 6-vertex configurations. Examples ... More
Polynomial inequalities representing polyhedraJul 14 2003Our main result is that every n-dimensional polytope can be described by at most (2n-1) polynomial inequalities and, moreover, these polynomials can explicitly be constructed. For an n-dimensional pointed polyhedral cone we prove the bound 2n-2 and for ... More
The isomorphism problem for multiparameter quantized Weyl algebrasMay 17 2014In this note we solve the isomorphism problem for the multiparameter quantized Weyl algebras, in the case when none of the deformation parameters q_i is a root of unity, over an arbitrary field.
A New Statistical Model for Population III Supernova Rates: Discriminating Between $Λ$CDM and WDM CosmologiesJun 20 2016Sep 19 2016With new observational facilities becoming available soon, discovering and characterising supernovae from the first stars will open up alternative observational windows to the end of the cosmic dark ages. Based on a semi-analytical merger tree model of ... More
Witnessing the birth of a supermassive protostarOct 09 2015Feb 04 2016The detection of $\rm z>6$ quasars reveals the existence of supermassive black holes of a few $\rm 10^9~M_{\odot}$. One of the potential pathways to explain their formation in the infant universe is the so-called direct collapse model which provides massive ... More
Searching for Efficient Multi-Scale Architectures for Dense Image PredictionSep 11 2018The design of neural network architectures is an important component for achieving state-of-the-art performance with machine learning systems across a broad array of tasks. Much work has endeavored to design and build architectures automatically through ... More
Statistical predictions for the first black holesJul 17 2018The recent observations of supermassive black holes (SMBHs) at high redshift challenge our understanding of their formation and growth. There are different proposed pathways to form black hole (BH) seeds, such as the remnants of the first stars (chapter ... More
On the reduction of the Siegel moduli space of abelian varieties of dimension 3 with Iwahori level structureNov 30 2009We study the moduli space of abelian threefolds with Iwahori level structure in positive characteristic. We explicitly determine the fibers of the canonical projection to the moduli space of principally polarized abelian varieties and draw conclusions ... More
Kottwitz-Rapoport and p-rank strata in the reduction of Shimura varieties of PEL typeOct 04 2012We study the reduction of certain integral models of Shimura varieties of PEL type with Iwahori level structure. On these spaces we have the Kottwitz-Rapoport and the $p$-rank stratification. We show that the $p$-rank is constant on a KR stratum, generalizing ... More
The elliptic GL(n) dynamical quantum group as an h-Hopf algebroidMar 26 2008May 15 2009Using the language of h-Hopf algebroids which was introduced by Etingof and Varchenko, we construct a dynamical quantum group, F_ell(GL(n)), from the elliptic solution of the quantum dynamical Yang-Baxter equation with spectral parameter associated to ... More
Principal Galois orders and Gelfand-Zeitlin modulesOct 11 2017We show that the ring of invariants in a skew monoid ring contains a so called standard Galois order. Any Galois ring contained in the standard Galois order is automatically itself a Galois order and we call such rings principal Galois orders. We give ... More
Time-Delay Interferometry and Clock-Noise CalibrationJul 07 2018The Laser Interferometer Space Antenna is a joint ESA-NASA space-mission to detect and study mHz cosmic gravitational waves. The trajectories followed by its three spacecraft result in unequal- and time-varying arms, requiring use of the Time-Delay Interferometry ... More
Training Object Detectors on Synthetic Images Containing Reflecting MaterialsMar 29 2019One of the grand challenges of deep learning is the requirement to obtain large labeled training data sets. While synthesized data sets can be used to overcome this challenge, it is important that these data sets close the reality gap, i.e., a model trained ... More
The $q$-difference Noether problem for complex reflection groups and quantum OGZ algebrasDec 31 2015Jun 17 2016For any complex reflection group $G=G(m,p,n)$, we prove that the $G$-invariants of the division ring of fractions of the $n$:th tensor power of the quantum plane is a quantum Weyl field and give explicit parameters for this quantum Weyl field. This shows ... More
Pseudo-unitarizable weight modules over generalized Weyl algebrasMar 05 2008Nov 25 2010We define a notion of pseudo-unitarizability for weight modules over a generalized Weyl algebra (of rank one, with commutative coeffiecient ring $R$), which is assumed to carry an involution of the form $X^*=Y$, $R^*\subseteq R$. We prove that a weight ... More
Coexistence of different magnetic moments in CeRuSn probed by polarized neutronsNov 03 2014We report on the spin densities in CeRuSn determined at elevated and at low temperatures using polarized neutron diffraction. At 285 K, where the CeRuSn crystal structure, commensurate with the CeCoAl type, contains two different crystallographic Ce sites, ... More
Formation of carbon-enhanced metal-poor stars as a consequence of inhomogeneous metal mixingDec 05 2018Jan 08 2019We present a novel scenario for the formation of carbon-enhanced metal-poor (CEMP) stars. Carbon enhancement at low stellar metallicities is usually considered a consequence of faint or other exotic supernovae. An analytical estimate of cooling times ... More
Twisted generalized Weyl algebras and primitive quotients of enveloping algebrasApr 21 2015To each multiquiver $\Gamma$ we attach a solution to the consistency equations associated to twisted generalized Weyl (TGW) algebras. This generalizes several previously obtained solutions in the literature. We show that the corresponding algebras $\mathcal{A}(\Gamma)$ ... More
The Tetrahedron algebra, the Onsager algebra, and the $\mathfrak{sl}_2$ loop algebraNov 02 2005Let $K$ denote a field with characteristic 0 and let $T$ denote an indeterminate. We give a presentation for the three-point loop algebra $\mathfrak{sl}_2 \otimes K\lbrack T, T^{-1},(T-1)^{-1}\rbrack$ via generators and relations. This presentation displays ... More
Unitarizability of weight modules over noncommutative Kleinian fiber productsFeb 27 2017For any $(m,n)$-periodic higher spin six-vertex configuration $\mathscr{L}$, we construct a one-parameter family $\Delta_\xi$ of pseudo-unitarizable representations of the corresponding noncommutative fiber product $\mathcal{A}(\mathscr{L})$ by difference ... More
Noncommutative fiber products and lattice modelsDec 24 2016Feb 27 2017We establish a connection between the representation theory of certain noncommutative singular varieties and two-dimensional lattice models. Specifically, we consider noncommutative biparametric deformations of the fiber product of two Kleinian singularities ... More
Locally finite simple weight modules over twisted generalized Weyl algebrasFeb 16 2005Apr 08 2005We present methods and explicit formulas for describing simple weight modules over twisted generalized Weyl algebras. When a certain commutative subalgebra is finitely generated over an algebraically closed field we obtain a classification of a class ... More
Twisted generalized Weyl algebras, polynomial Cartan matrices and Serre-type relationsAug 14 2009Twisted generalized Weyl algebras (TGWAs) are defined as the quotient of a certain graded algebra by the maximal graded ideal I with trivial zero component, analogous to how Kac-Moody algebras can be defined. In this paper we introduce the class of locally ... More
Hopf Structures on Ambiskew Polynomial RingsOct 18 2005We derive necessary and sufficient conditions for an ambiskew polynomial ring to have a Hopf algebra structure of a certain type. This construction generalizes many known Hopf algebras, for example U(sl2), U_q(sl2) and the enveloping algebra of the 3-dimensional ... More
The iMaterialist Fashion Attribute DatasetJun 13 2019Jun 14 2019Large-scale image databases such as ImageNet have significantly advanced image classification and other visual recognition tasks. However much of these datasets are constructed only for single-label and coarse object-level classification. For real-world ... More
On the Consistency of Twisted Generalized Weyl AlgebrasMar 22 2011Apr 07 2011A twisted generalized Weyl algebra A of degree n depends on a base algebra R, n commuting automorphisms s_i of R, n central elements t_i of R and on some additional scalar parameters. In a paper by V.Mazorchuk and L.Turowska (1999) it is claimed that ... More
Clifford and Weyl superalgebras and spinor representationsJul 11 2018We construct a family of twisted generalized Weyl algebras which includes Weyl-Clifford superalgebras and quotients of the enveloping algebras of $\mathfrak{gl}(m|n)$ and $\mathfrak{osp}(m|2n)$. We give a condition for when a canonical representation ... More
Cylindrical Dyck paths and the Mazorchuk-Turowska equationJul 15 2015We classify all solutions (p,q) to the equation p(u)q(u)=p(u+b)q(u+a) where p and q are complex polynomials in one indeterminate u, and a and b are fixed but arbitrary complex numbers. This equation is a special case of a system of equations which ensures ... More
Descendants of the first stars: the distinct chemical signature of second generation starsJan 15 2018Jul 16 2018Extremely metal-poor (EMP) stars in the Milky Way (MW) allow us to infer the properties of their progenitors by comparing their chemical composition to the metal yields of the first supernovae. This method is most powerful when applied to mono-enriched ... More
Multiparameter Twisted Weyl AlgebrasMar 28 2011We introduce a new family of twisted generalized Weyl algebras, called multiparameter twisted Weyl algebras, for which we parametrize all simple quotients of a certain kind. Both Jordan's simple localization of the multiparameter quantized Weyl algebra ... More
Classification of twisted generalized Weyl algebras over polynomial ringsMar 28 2019Let $R$ be a polynomial ring in $m$ variables over a field of characteristic zero. We classify all rank $n$ twisted generalized Weyl algebras over $R$, up to $\mathbb{Z}^n$-graded isomorphisms, in terms of higher spin 6-vertex configurations. Examples ... More
Simple Whittaker modules over free bosonic orbifold vertex operator algebrasJun 15 2018We construct weak (i.e. non-graded) modules over the vertex operator algebra $M(1)^+$, which is the fixed-point subalgebra of the higher rank free bosonic (Heisenberg) vertex operator algebra with respect to the $-1$ automorphism. These weak modules are ... More
De Concini-Kac filtration and Gelfand-Tsetlin characters for quantum gl_NMar 21 2012It was shown by the first author and Ovsienko that the universal enveloping algebra of $\mathfrak{gl}_N$ is a Galois order, that is, it has a hidden invariant skew group structure. We extend this result to the quantized case and prove that $U_q(\mathfrak{gl}_N)$ ... More
Simplicity and maximal commutative subalgebras of twisted generalized Weyl algebrasSep 24 2010Oct 17 2010In this paper we show that each non-zero ideal of a twisted generalized Weyl algebra (TGWA) $A$ intersects the centralizer of the distinguished subalgebra $R$ in $A$ non-trivially. We also provide a necessary and sufficient condition for the centralizer ... More
Twisted Weyl algebras, crossed products, and representationsMay 03 2010Mar 22 2011We prove that any twisted generalized Weyl algebra satisfying certain consistency conditions can be embedded into a crossed product. We also introduce a new family of twisted generalized Weyl algebras, called multiparameter twisted Weyl algebras, for ... More
Solution of a q-difference Noether problem and the quantum Gelfand-Kirillov conjecture for gl_NNov 25 2011Nov 29 2011It is shown that the q-difference Noether problem for all classical Weyl groups has a positive solution, simultaneously generalizing well known results on multisymmetric functions of Mattuck and Miyata in the case q=1, and q-deforming the noncommutative ... More
Active Galactic Nuclei outflows in galaxy discsJul 12 2017Apr 09 2018Galactic outflows, driven by active galactic nuclei (AGN), play a crucial role in galaxy formation and in the self-regulated growth of supermassive black holes (BHs). AGN feedback couples to and affects gas, rather than stars, and in many, if not most, ... More
Miniaturized lab system for future cold atom experiments in microgravityOct 31 2016We present the technical realization of a compact system for performing experiments with cold $^{87}{\text{Rb}}$ and $^{39}{\text{K}}$ atoms in microgravity in the future. The whole system fits into a capsule to be used in the drop tower Bremen. One of ... More
Generalized Young Symmetrizers for the Analysis of Control Systems on Tensor SpacesJun 04 2018We describe a method to analyze and decompose the dynamics of a control system on a Lie group subject to symmetries. The method is based on the concept of generalized Young symmetrizers of representation theory. It naturally applies to the situation where ... More
Irreducible completely pointed modules of quantum groups of type $A$Apr 01 2014Jun 23 2014We give a classification of all irreducible completely pointed $U_q(\mathfrak{sl}_{n+1})$ modules over a characteristic zero field in which $q$ is not a root of unity. This generalizes the classification result of Benkart, Britten and Lemire in the non ... More
Ideal-specific elimination orders form a star-shaped regionFeb 13 2012Apr 19 2013This paper shows that Gr\"obner walks aiming for the elimination of variables from a polynomial ideal can be terminated much earlier than previously known. To this end we provide an improved stopping criterion for a known Gr\"obner walk algorithm for ... More
Deformations of Lie Algebras using $σ$-derivationsAug 04 2004In this article we develop an approach to deformations of the Witt and Virasoro algebras based on $\sigma$-derivations. We show that $\sigma$-twisted Jacobi type identity holds for generators of such deformations. For the $\sigma$-twisted generalization ... More
Extended trigonometric Cherednik algebras and nonstationary Schrödinger equations with delta-potentialsApr 28 2011Jun 12 2012We realize an extended version of the trigonometric Cherednik algebra as affine Dunkl operators involving Heaviside functions. We use the quadratic Casimir element of the extended trigonometric Cherednik algebra to define an explicit nonstationary Schr\"odinger ... More
Gravitational Wave Signals from the First Massive Black Hole SeedsMay 17 2018Jul 23 2018Recent numerical simulations reveal that the isothermal collapse of pristine gas in atomic cooling haloes may result in stellar binaries of supermassive stars with $M_* \gtrsim 10^4\ \mathrm{M}_{\odot}$. For the first time, we compute the in-situ merger ... More
Detection strategies for the first supernovae with JWSTNov 15 2017May 16 2018Pair-instability supernovae (PISNe) are very luminous explosions of massive, low metallicity stars. They can potentially be observed out to high redshifts due to their high explosion energies, thus providing a probe of the Universe prior to reionization. ... More
InclusiveFaceNet: Improving Face Attribute Detection with Race and Gender DiversityDec 01 2017Jul 17 2018We demonstrate an approach to face attribute detection that retains or improves attribute detection accuracy across gender and race subgroups by learning demographic information prior to learning the attribute detection task. The system, which we call ... More
An Agent-Based Approach to Self-Organized ProductionDec 21 2010The chapter describes the modeling of a material handling system with the production of individual units in a scheduled order. The units represent the agents in the model and are transported in the system which is abstracted as a directed graph. Since ... More
Fingerprint of the first stars: multi-enriched extremely metal-poor stars in the TOPoS surveyOct 10 2018Extremely metal poor (EMP) stars in the Milky Way inherited the chemical composition of the gas out of which they formed. They therefore carry the chemical fingerprint of the first stars in their spectral lines. It is commonly assumed that EMP stars form ... More
Quantum affine modules for non-twisted affine Kac-Moody algebrasMay 21 2014Oct 30 2014We construct new irreducible weight modules over quantum affine algebras of type I with all weight spaces infinite-dimensional. These modules are obtained by parabolic induction from irreducible modules over the Heisenberg subalgebra.
Rethinking Atrous Convolution for Semantic Image SegmentationJun 17 2017Dec 05 2017In this work, we revisit atrous convolution, a powerful tool to explicitly adjust filter's field-of-view as well as control the resolution of feature responses computed by Deep Convolutional Neural Networks, in the application of semantic image segmentation. ... More
Neutron diagnostics for the physics of a high-field, compact, $Q\geq1$ tokamakMar 22 2019Advancements in high temperature superconducting technology have opened a path toward high-field, compact fusion devices. This new parameter space introduces both opportunities and challenges for diagnosis of the plasma. This paper presents a physics ... More
Was ordinary matter synthesised from mirror matter? An attempt to explain why $Ω_{Baryon} \approx 0.2Ω_{Dark}$Apr 28 2003Jun 03 2003The cosmological dust has begun to settle. A likely picture is a universe comprised (predominantly) of three components: ordinary baryons ($\Omega_B \approx 0.05$), non-baryonic dark matter ($\Omega_{Dark} \approx 0.22$) and dark energy ($\Omega_{\Lambda} ... More
How neutrino oscillations can induce an effective neutrino number of less than 3 during Big Bang NucleosynthesisJun 04 1997Ordinary-sterile neutrino oscillations can generate significant neutrino asymmetry in the early Universe. In this paper we extend this work by computing the evolution of neutrino asymmetries and light element abundances during the Big Bang Nucleosynthesis ... More
Maximal neutrino oscillation solution to the solar neutrino problemOct 17 1995We discuss a simple predictive solution to the solar neutrino problem based on maximal vacuum neutrino oscillations. The solution can be motivated by the exact parity symmetric model which predicts that the neutrino mass eigenstates are maximal mixtures ... More
A mirror world explanation for the Pioneer spacecraft anomalies?Aug 06 2001We show that the anomalous acceleration of the Pioneer 10/11 spacecraft can be explained if there is some mirror gas or mirror dust in our solar system.
The exact parity symmetric model and big bang nucleosynthesisDec 04 1996The assumption of exact, unbroken parity symmetry leads directly to a simple predictive resolution of the atmospheric and solar neutrino puzzles. This is because the existence of this symmetry implies the existence of a set of mirror neutrinos which must ... More
Auto-DeepLab: Hierarchical Neural Architecture Search for Semantic Image SegmentationJan 10 2019Recently, Neural Architecture Search (NAS) has successfully identified neural network architectures that exceed human designed ones on large-scale image classification problems. In this paper, we study NAS for semantic image segmentation, an important ... More
Gravitational Waves from the Remnants of the First StarsMar 17 2016May 19 2016Gravitational waves (GWs) provide a revolutionary tool to investigate yet unobserved astrophysical objects. Especially the first stars, which are believed to be more massive than present-day stars, might be indirectly observable via the merger of their ... More
MaskLab: Instance Segmentation by Refining Object Detection with Semantic and Direction FeaturesDec 13 2017In this work, we tackle the problem of instance segmentation, the task of simultaneously solving object detection and semantic segmentation. Towards this goal, we present a model, called MaskLab, which produces three outputs: box detection, semantic segmentation, ... More
Detailed Report of the MuLan Measurement of the Positive Muon Lifetime and Determination of the Fermi ConstantNov 05 2012We present a detailed report of the method, setup, analysis and results of a precision measurement of the positive muon lifetime. The experiment was conducted at the Paul Scherrer Institute using a time-structured, nearly 100%-polarized, surface muon ... More
Legendrian contact homology and topological entropySep 12 2014Apr 23 2016In this paper we study the growth rate of a version of Legendrian contact homology, which we call strip Legendrian contact homology, in 3-dimensional contact manifolds and its relation to the topological entropy of Reeb flows. We show that: if for a pair ... More
The heat-kernel and the average effective potentialMay 29 1995We discuss the definition of the average effective action in terms of the heat-kernel. As an example we examine a model describing a self-interacting scalar field, both in flat and curved background, and study the renormalization group flow of some of ... More
The renormalization group flow of the dilaton potentialDec 20 1994We consider a scalar-metric gauge theory of gravity with independent metric, connection and dilaton. The role of the dilaton is to provide the scale of all masses, via its vacuum expectation value. In this theory, we study the renormalization group flow ... More
Ordinary-derivative formulation of conformal low-spin fieldsJul 30 2007Nov 14 2011Conformal fields in flat space-time of even dimension greater than or equal to four are studied. Second-derivative formulation for spin 0,1,2 conformal bosonic fields and first-derivative formulation for spin 1/2,3/2 conformal fermionic fields are developed. ... More
Gravitational and higher-derivative interactions of massive spin 5/2 field in (A)dS spaceDec 27 2006Sep 10 2007Using on-shell gauge invariant formulation of relativistic dynamics we study interaction vertices for a massive spin 5/2 Dirac field propagating in (A)dS space of dimension greater than or equal to four. Gravitational interaction vertex for the massive ... More
CFT adapted gauge invariant formulation of arbitrary spin fields in AdS and modified de Donder gaugeAug 28 2008Jan 22 2009Using Poincare parametrization of AdS space, we study totally symmetric arbitrary spin massless fields in AdS space of dimension greater than or equal to four. CFT adapted gauge invariant formulation for such fields is developed. Gauge symmetries are ... More
CFT adapted approach to massless fermionic fields, AdS/CFT, and fermionic conformal fieldsNov 28 2013Dec 10 2013Fermionic totally symmetric arbitrary spin massless fields in AdS space of dimension greater than or equal to four are studied. Using Poincar\'e parametrization of AdS space, CFT adapted gauge invariant formulation for such fields is developed. We demonstrate ... More
The Color-Flavor Locking Phase at T \not =0$Sep 17 1999Nov 03 1999We study the color-flavor locked phase of QCD with three massless quarks at high chemical potential and small non zero temperatures. We make use of the recently introduced effective action to describe such a phase. We obtain the exact order T^2 behaviour ... More
TARCER - A Mathematica program for the reduction of two-loop propagator integralsJan 21 1998TARCER is an implementation of the recurrence algorithm of O.V. Tarasov for the reduction of two-loop propagator integrals with arbitrary masses to a small set of basis integrals. The tensor integral reduction scheme is adapted to moment integrals emerging ... More
Implications of the JHF-Kamioka neutrino oscillation experimentNov 20 2002After quickly reviewing the existing evidence for neutrino oscillations, I summarise the goals and capabilities of the JHF-Kamioka long baseline superbeam experiment. Theoretical implications of what this experiment could potentially discover are then ... More
Testing the paradigm of adiabaticityFeb 02 2004We introduce the concepts of adiabatic (curvature) and isocurvature (entropy) cosmological perturbations and present their relevance for parameter estimation from cosmic microwave background anisotropies data. We emphasize that, while present-day data ... More
Automated Checking and Visualization of Interlocks in the ISAC Control SystemNov 09 2001The EPICS based control system of the ISAC radioactive beam facility supervises several sub-systems, which are controlled by PLCs. Most of the devices are protected by non-trivial interlocks, which are implemented with ladder-logic software. Detailed ... More
On the q-analogues of the Zassenhaus formula for dientangling exponential operatorsDec 24 2002Apr 28 2003Katriel, Rasetti and Solomon introduced a $q$-analogue of the Zassenhaus formula written as $e_q^{(A+B)}$ $=$ $e_q^Ae_q^Be_q^{c_2}e_q^{c_3}e_q^{c_4}e_q^{c_5}...$, where $A$ and $B$ are two generally noncommuting operators and $e_q^z$ is the Jackson $q$-exponential, ... More
Casimir-Polder force density between an atom and a conducting wallNov 14 2006In this paper we calculate the Casimir-Polder force density (force per unit area acting on the elements of the surface) on a metallic plate placed in front of a neutral atom. To obtain the force density we use the quantum operator associated to the electromagnetic ... More
An Algorithm for the Microscopic Evaluation of the Coefficients of the Seiberg-Witten PrepotentialAug 25 2002Sep 14 2002A procedure, allowing to calculate the coefficients of the SW prepotential in the framework of the instanton calculus is presented. As a demonstration explicit calculations for 2, 3 and 4- instanton contributions are carried out.
Thermostatistics of extensive and non-extensive systems using generalized entropiesMay 04 2000We describe in detail two numerical simulation methods valid to study systems whose thermostatistics is described by generalized entropies, such as Tsallis. The methods are useful for applications to non-trivial interacting systems with a large number ... More
Extremal size fluctuations in QCD dipole cascadingFeb 07 2005Oct 28 2005This paper has been superseded by hep-ph/0510352.
Free Fields Equations For Space-Time Algebras With Tensorial MomentumDec 25 2001Free field equations, with various spins, for space-time algebras with second-rank tensor (instead of usual vector) momentum are constructed. Similar algebras are appearing in superstring/M theories. The most attention is payed to the gauge invariance ... More
On the Evolution of Scalar Metric Perturbations in an Inflationary CosmologySep 15 1995We further clarify how scalar metric perturbations are amplified in an inflationary cosmology. We first construct a simple, analytic model of an inflationary cosmology in which the expansion scale factor evolves continuously from an inflationary era to ... More
Fluid Limits of Pure Jump Markov Processes: a Practical GuideOct 08 2002Dec 23 2002A rescaled Markov chain converges uniformly in probability to the solution of an ordinary differential equation, under carefully specified assumptions. The presentation is much simpler than those in the outside literature. The result may be used to build ... More
Preliminary Investigation of a Waveform Analysis with the WASA and the ACQIRIS Readout ElectronicsJun 28 2013Jul 16 2013The Group for the development of neutron and gamma detectors in the Central Institute of Engineering, Electronics and Analytics (ZEA-2) at Forschungszentrum J\"ulich (FZJ) is developing a fast Anger Camera prototype for improving the rejection of the ... More
Bound states in a hyperbolic asymmetric double-wellJun 12 2013Nov 23 2013We report a new class of hyperbolic asymmetric double-well whose bound state wavefunctions can be expressed in terms of confluent Heun functions. An analytic procedure is used to obtain the energy eigenvalues and the criterion for the potential to support ... More
Groupoids Determined by Involutive Automorphisms on Semilattices of GroupsMar 01 2015Jun 02 2017We give several characterisations of groupoids determined by involutive automorphisms on semilattices of groups.
Legendrian contact homology and topological entropySep 12 2014May 08 2017In this paper we study the growth rate of a version of Legendrian contact homology, which we call strip Legendrian contact homology, in 3-dimensional contact manifolds and its relation to the topological entropy of Reeb flows. We show that: if for a pair ... More
Skewness, kurtosis and Newton's inequalitySep 11 2013Feb 21 2014We show that an inequality related to Newton's inequality provides one more relation between skewness and kurtosis. This also gives simple and alternative proofs of the bounds for skewness and kurtosis.
Encoder-Decoder with Atrous Separable Convolution for Semantic Image SegmentationFeb 07 2018Spatial pyramid pooling module or encode-decoder structure are used in deep neural networks for semantic segmentation task. The former networks are able to encode multi-scale contextual information by probing the incoming features with filters or pooling ... More
Constraining the primordial initial mass function with stellar archaeologyNov 05 2014May 03 2015We present a new near-field cosmological probe of the initial mass function (IMF) of the first stars. Specifically, we constrain the lower-mass limit of the Population III (Pop III) IMF with the total number of stars in large, unbiased surveys of the ... More
A new approach to determine optically thick H2 cooling and its effect on primordial star formationJul 02 2014Nov 19 2014We present a new method for estimating the H2 cooling rate in the optically thick regime in simulations of primordial star formation. Our new approach is based on the TreeCol algorithm, which projects matter distributions onto a spherical grid to create ... More
FEELVOS: Fast End-to-End Embedding Learning for Video Object SegmentationFeb 25 2019Apr 08 2019Many of the recent successful methods for video object segmentation (VOS) are overly complicated, heavily rely on fine-tuning on the first frame, and/or are slow, and are hence of limited practical use. In this work, we propose FEELVOS as a simple and ... More
Geo-Aware Networks for Fine Grained RecognitionJun 04 2019Fine grained recognition distinguishes among categories with subtle visual differences. To help identify fine grained categories, other information besides images has been used. However, there has been little effort on using geolocation information to ... More
Reconciling sterile neutrinos with big bang nucleosynthesisAug 10 1995Nov 08 1995We re-examine the big bang nucleosynthesis (BBN) bounds on the mixing of neutrinos with sterile species. These bounds depend on the assumption that the relic neutrino asymmetry $L_{\nu}$ is very small. We show that for $L_{\nu}$ large enough (greater ... More
Implications of mirror neutrinos for early universe cosmologyApr 15 1999The Exact Parity Model (EPM) is, in part, a theory of neutrino mass and mixing that can solve the atmospheric, solar and LSND anomalies. The central feature of the neutrino sector is three pairs of maximally mixed ordinary and mirror neutrinos. It has ... More
Generalised leptonic colourJul 05 2006Dec 06 2006It is conceivable that there is an $SU(N)_{\ell}$ `colour' gauge group for leptons, analogous to the gauged $SU(3)_q$ colour group of the quarks. The standard model emerges as the low energy effective theory when the leptonic colour is spontaneously broken. ... More
Spheroidal galactic halos and mirror dark matterJul 26 2004Mirror matter has been proposed as a dark matter candidate. It has several very attractive features, including automatic stability and darkness, the ability to mimic the broad features of cold dark matter while in the linear density perturbation regime, ... More
New and improved quark-lepton symmetric modelsMay 18 1995We show how the use of a see-saw mechanism based on a $3 \times 3$ neutrino mass matrix texture can considerably simplify Higgs sectors for quark-lepton symmetric models (and for Standard Model extensions generally). The main theory we discuss also incorporates ... More
Measurement of the Positive Muon Lifetime and Determination of the Fermi Constant to Part-per-Million PrecisionOct 05 2010Dec 06 2010We report a measurement of the positive muon lifetime to a precision of 1.0 parts per million (ppm); it is the most precise particle lifetime ever measured. The experiment used a time-structured, low-energy muon beam and a segmented plastic scintillator ... More