Results for "Patrick Drew"

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An Analysis of ALMA Deep Fields and the Perceived Dearth of High-z GalaxiesJun 14 2018Deep, pencil-beam surveys from ALMA at 1.1-1.3mm have uncovered an apparent absence of high-redshift dusty galaxies, with existing redshift distributions peaking around $z\sim1.5-2.5$. This has led to a perceived dearth of dusty systems at $z>4$, and ... More
The sorting order on a Coxeter groupDec 07 2007Mar 30 2009Let $(W,S)$ be an arbitrary Coxeter system. For each word $\omega$ in the generators we define a partial order--called the {\sf $\omega$-sorting order}--on the set of group elements $W_\omega\subseteq W$ that occur as subwords of $\omega$. We show that ... More
The Brightest Galaxies in the Dark Ages: Galaxies' Dust Continuum Emission During the Reionization EraMay 25 2018Though half of cosmic starlight is absorbed by dust and reradiated at long wavelengths (3$\mu$m-3mm), constraints on the infrared through millimeter galaxy luminosity function (the `IRLF') are poor in comparison to the rest-frame ultraviolet and optical ... More
Do Price Ranges Increase Click-throughs?May 15 2016An important goal of online comparison shopping services is to "convert" a viewer from general product category pages (for example product groups such as "smartphones" or "air-conditioners") to detailed product pages and ultimately to order pages. Comparison ... More
Observation of the Dyakonov-Tamm WaveNov 18 2013A surface electromagnetic wave called the Dyakonov-Tamm wave has been theoretically predicted to exist at the interface of two dielectric materials at least one of which is both anisotropic and periodically nonhomogeneous. For experimental confirmation, ... More
Convergence of thresholding schemes incorporating bulk effectsJan 11 2016Dec 01 2016In this paper we establish the convergence of three computational algorithms for interface motion in a multi-phase system, which incorporate bulk effects. The algorithms considered fall under the classification of thresholding schemes, in the spirit of ... More
Topological SpeedupsMay 26 2016Given a dynamical system $(X,T)$ one can define a speedup of $(X,T)$ as another dynamical system conjugate to $S:X\rightarrow X$ where $S(x)=T^{p(x)}(x)$ for some function $p:X\rightarrow\mathbb{Z}^{+}$. In $1985$ Arnoux, Ornstein, and Weiss showed that ... More
Functional renormalization group approach to neutron matterApr 03 2014Sep 30 2014The chiral nucleon-meson model, previously applied to systems with equal number of neutrons and protons, is extended to asymmetric nuclear matter. Fluctuations are included in the framework of the functional renormalization group. The equation of state ... More
Scale and curvature effects in principal geodesic analysisOct 05 2016Oct 06 2016There is growing interest in using the close connection between differential geometry and statistics to model smooth manifold-valued data. In particular, much work has been done recently to generalize principal component analysis (PCA), the method of ... More
Algorithms for realizing degree sequences of directed graphsJun 01 2009Jun 08 2010The Havel-Hakimi algorithm for constructing realizations of degree sequences for undirected graphs has been used extensively in the literature. A result by Kleitman and Wang extends the Havel-Hakimi algorithm to degree sequences for directed graphs. In ... More
The magneto-optical Faraday effect in spin liquid candidatesJul 23 2014We propose an experiment to use the magneto-optical Faraday effect to probe the dynamic Hall conductivity of spin liquid candidates. Theory predicts that an external magnetic field will generate an internal gauge field. If the source of conductivity is ... More
A decomposition of the group algebra of a hyperoctahedral groupNov 11 2016The descent algebra of a finite Coxeter group W is a subalgebra of the group algebra defined by Solomon. Descent algebras of symmetric groups have properties that are not shared by other Coxeter groups. For instance, the natural map from the descent algebra ... More
Taking Census of Massive, Star-Forming Galaxies formed <1 Gyr After the Big BangMar 13 2019Two decades of effort have been poured into both single-dish and interferometric millimeter-wave surveys of the sky to infer the volume density of dusty star-forming galaxies (DSFGs, with SFR>100M$_\odot$ yr$^{-1}$) over cosmic time. Though obscured galaxies ... More
Towards Least Privilege Containers with CimplifierFeb 26 2016Application containers, such as Docker containers, have recently gained popularity as a solution for agile and seamless deployment of applications. These light-weight virtualization environments run applications that are packed together with their resources ... More
Local duality in algebra and topologyNov 11 2015Jul 31 2018The first goal of this paper is to provide an abstract framework in which to formulate and study local duality in various algebraic and topological contexts. For any stable $\infty$-category $\mathcal{C}$ together with a collection of compact objects ... More
Transforming how water is managed in the WestSep 28 2016California is challenged by its worst drought in 600 years and faces future water uncertainty. Pioneering new data infrastructure to integrate water use data across California's more than a thousand water providers will support water managers in ensuring ... More
Hyperplane Arrangements and Diagonal HarmonicsMay 11 2010In 2003, Haglund's {\sf bounce} statistic gave the first combinatorial interpretation of the $q,t$-Catalan numbers and the Hilbert series of diagonal harmonics. In this paper we propose a new combinatorial interpretation in terms of the affine Weyl group ... More
Verdier quotients of stable quasi-categories are localizationsNov 26 2015The Verdier quotient $\mathcal{T}/\mathcal{S}$ of a triangulated category $\mathcal{T}$ by a triangulated subcategory $\mathcal{S}$ is defined by a universal property with respect to triangulated functors out of $\mathcal{T}$. However, $\mathcal{T}/\mathcal{S}$ ... More
Strongly residual coordinates over A[x]Apr 05 2013May 14 2013For a domain A of characteristic zero, a polynomial f over A[x] is called a strongly residual coordinate if f becomes a coordinate (over A) upon going modulo x, and f becomes a coordinate upon inverting x. We study the question of when a strongly residual ... More
Venereau-type polynomials as potential counterexamplesJul 14 2010Sep 25 2012We study some properties of the Venereau polynomials b_m=y+x^m(xz+y(yu+z^2)), a sequence of proposed counterexamples to the Abhyankar-Sathaye embedding conjecture and the Dolgachev-Weisfeiler conjecture. It is well known that these are hyperplanes and ... More
Landau-Ginzburg Mirror Symmetry for Orbifolded Frobenius AlgebrasNov 10 2011We prove the Landau-Ginzburg Mirror Symmetry Conjecture at the level of (orbifolded) Frobenius algebras for a large class of invertible singularities, including arbitrary sums of loops and Fermats with arbitrary symmetry groups. Specifically, we show ... More
What are the visual features underlying human versus machine vision?Jan 10 2017Nov 07 2017Although Deep Convolutional Networks (DCNs) are approaching the accuracy of human observers at object recognition, it is unknown whether they leverage similar visual representations to achieve this performance. To address this, we introduce Clicktionary, ... More
Computing upper bounds for optimal density of $(t,r)$ broadcasts on the infinite gridDec 01 2017The domination number of a finite graph $G$ with vertex set $V$ is the cardinality of the smallest set $S\subseteq V$ such that for every vertex $v\in V$ either $v\in S$ or $v$ is adjacent to a vertex in $S$. A set $S$ satisfying these conditions is called ... More
Near-infrared line spectropolarimetry of hot massive starsSep 22 2005In order to study the inner parts of the circumstellar material around optically faint, infrared bright objects, we present the first medium-resolution spectropolarimetric data taken in the near-infrared. In this paper we discuss Pa beta line data of ... More
The multi-detector F-statistic metric for short-duration non-precessing inspiral gravitational-wave signalsAug 11 2012We derive explicit expressions for the multi-detector F-statistic metric applied to short-duration non-precessing inspiral signals. This is required for template bank production associated with coherent searches for short-duration non-precessing inspiral ... More
Motivic Hodge modulesJan 30 2018We construct a quasi-categorically enhanced Grothendieck six-functor formalism on schemes of finite type over the complex numbers. In addition to satisfying many of the same properties as M. Saito's derived categories of mixed Hodge modules, this new ... More
Parameter space metric for 3.5 post-Newtonian gravitational-waves from compact binary inspiralsMay 23 2013We derive the metric on the parameter space of 3.5 post-Newtonian (3.5PN) stationary phase compact binary inspiral waveforms for a single detector, neglecting spin, eccentricity, and finite-body effects. We demonstrate that this leads to better template ... More
Self-Organizing Machine Translation: Example-Driven Induction of Transfer FunctionsJun 03 1994With the advent of faster computers, the notion of doing machine translation from a huge stored database of translation examples is no longer unreasonable. This paper describes an attempt to merge the Example-Based Machine Translation (EBMT) approach ... More
Dynamics of Irreducible Endomorphisms of $F_n$Aug 21 2010Mar 06 2011We consider the class non-surjective irreducible endomorphisms of the free group $F_n$. We show that such an endomorphism $\phi$ is topologically represented by a simplicial immersion $f:G \rightarrow G$ of a marked graph $G$; along the way we classify ... More
Observation of scattering and absorption centers in lead fluoride crystalsJun 22 2006For the first time, lead fluoride is used as a fast and compact material in electromagnetic calorimetry. Excellent optical and mechanical properties of the pure Cherenkov crystals are necessary for the A4 collaboration to perform a measurement of the ... More
Duality for toric Landau-Ginzburg modelsMar 04 2008We introduce a duality construction for toric Landau-Ginzburg models, applicable to complete intersections in toric varieties via the sigma model / Landau-Ginzburg model correspondence. This construction is shown to reconstruct those of Batyrev-Borisov, ... More
Large-scale bias of dark matter halosSep 06 2010Feb 09 2011We build a simple analytical model for the bias of dark matter halos that applies to objects defined by an arbitrary density threshold, $200\leq\deltas\leq 1600$, and that provides accurate predictions from low-mass to high-mass halos. We point out that ... More
Improving three-dimensional mass mapping with weak gravitational lensing using galaxy clusteringMar 28 2012Nov 01 2013The weak gravitational lensing distortion of distant galaxy images (defined as sources) probes the projected large-scale matter distribution in the Universe. To improve quality in the 3D mass mapping using 3D-lensing, we combine the lensing information ... More
Límites directos de prolongaciones de algebroides de LieOct 29 2013Jun 02 2016We prove that direct limits of finite dimensional Lie algebroids and their prolongations can be endowed with structures of convenient spaces.
Specializations of elliptic surfaces, and divisibility in the Mordell-Weil groupNov 19 2008Dec 10 2008Let $E$ be an elliptic surface over the curve $C$, defined over a number field $k$, let $P$ be a section of $E$, and let $\ell$ be a rational prime. For any non-singular fibre $E_t$, we bound the number of points $Q$ on $E_t$ of (algebraic) degree at ... More
Duality for toric Landau-Ginzburg modelsMar 04 2008Dec 16 2016We introduce a duality construction for toric Landau-Ginzburg models, applicable to complete intersections in toric varieties via the sigma model / Landau-Ginzburg model correspondence. This construction is shown to reconstruct those of Batyrev-Borisov, ... More
Metrics for multi-detector template placement in searches for short-duration nonprecessing inspiral gravitational-wave signalsJul 16 2013Using the family of multi-detector F-statistic metrics for short duration, nonprecessing inspiral signals, we derive a marginalized metric that is directly applicable to the problem of generating template banks for coincident and coherent multi-detector ... More
The balancing act of template bank construction: inspiral waveform template banks for gravitational-wave detectors and optimizations at fixed computational costMar 08 2013Gravitational-wave searches for signals from inspiralling compact binaries have relied on matched filtering banks of waveforms (called template banks) to try to extract the signal waveforms from the detector data. These template banks have been constructed ... More
Factors influencing the decision of Saudi consumers to purchase form online retailers: Quantitative AnalysisNov 11 2012This paper presents the preliminary findings of a study researching the diffusion and the adoption of online retailing in Saudi Arabia. It reports new research that identifies and explores the key issues that positively and negatively influence the decision ... More
Determining Tropical HypersurfacesSep 18 2015Sep 23 2016We consider the question of when points in tropical affine space uniquely determine a tropical hypersurface. We introduce a notion of multiplicity of points so that this question may be meaningful even if some of the points coincide. We give a geometric/combinatorial ... More
Optimal $(t,r)$ Broadcasts On the Infinite GridNov 29 2017Let $G=(V,E)$ be a graph and $t,r$ be positive integers. The signal that a vertex $v$ receives from a tower of signal strength $t$ located at vertex $T$ is defined as $sig(v,T)=max(t-dist(v,T),0)$, where $dist(v,T)$ denotes the distance between the vertices ... More
Molecules in QSOs and QSO Absorption Line Systems at High RedshiftApr 24 1998Molecules dominate the cooling function of neutral metal-poor gas at high density. Observation of molecules at high redshift is thus an important tool toward understanding the physical conditions prevailing in collapsing gas. Up to now, detections are ... More
High Energy Studies of Pulsar Wind NebulaeNov 12 2008The extended nebulae formed as pulsar winds expand into their surroundings provide information about the composition of the winds, the injection history from the host pulsar, and the material into which the nebulae are expanding. Observations from across ... More
Thermal X-ray Spectra of Supernova RemnantsSep 23 2013The fast shocks that characterize supernova remnants heat circumstellar and ejecta material to extremely high temperatures, resulting in significant X-ray emission. The X-ray spectrum from an SNR carries a wealth of information about the temperature and ... More
Chandra Studies of Nonthermal Emission from Supernova Remnants and Pulsar Wind NebulaeDec 16 2002While supernova remnants (SNRs) have long been considered prime candidates as sources of cosmic rays, it is only recently that X-ray observations have identified several shell-type SNRs dominated by nonthermal emission, thus revealing shock-accelerated ... More
Isolated-Word Confusion Metrics and the PGPfone AlphabetAug 29 1996Although the confusion of individual phonemes and features have been studied and analyzed since (Miller and Nicely, 1955), there has been little work done on extending this to a predictive theory of word-level confusions. The PGPfone alphabet is a good ... More
Incorporating "Unconscious Reanalysis" into an Incremental, Monotonic ParserFeb 24 1995This paper describes an implementation based on a recent model in the psycholinguistic literature. We define a parsing operation which allows the reanalysis of dependencies within an incremental and monotonic processing architecture, and discuss search ... More
Effective field theories for QED bound states: extending Nonrelativistic QED to study retardation effectsAug 29 1996Nonrelativistic QED bound states are difficult to study because of the presence of at least three widely different scales: the masses, three-momenta ($p_i$) and kinetic energies ($K_i$) of the constituents. Nonrelativistic QED (NRQED), an effective field ... More
Using groups for investigating rewrite systemsSep 18 2006We describe several technical tools that prove to be efficient for investigating the rewrite systems associated with a family of algebraic laws, and might be useful for more general rewrite systems. These tools consist in introducing a monoid of partial ... More
The critical height is a moduli heightOct 25 2016The critical height of a rational function (with algebraic coefficients) is a natural measure of dynamical complexity, essentially an adelic analogue of the Lyapunov exponent. Coordinate-free, it is well-defined on moduli space, but bears no obvious relation ... More
A lower bound for the canonical height associated to a Drinfeld moduleOct 08 2012Dec 29 2012Denis associated to each Drinfeld module M over a global function function field L a canonical height function, which plays a role analogous to that of the Neron-Tate height in the context of elliptic curves. We prove that there exist constants \epsilon>0 ... More
New Double-Mode and Other RR Lyrae Stars from WASP DataNov 05 201042 RRab, 46 RRc and 7 previously unidentified double-mode RR Lyrae stars were found in the publicly available data of the WASP archive. The Galactic double-mode RR Lyrae stars appear to show a bimodal period distribution.
CP, T and CPT violation in future long baseline experimentsOct 09 2002I give a short overview about the possibilities and problems related to the measurement of CP violation in long baseline experiments. Special attention is paid to the issue of degeneracies and a method for their resolution is quantitatively discussed. ... More
WIMPy LeptogenesisFeb 05 2014We consider a class of leptogenesis models in which the lepton asymmetry arises from dark matter annihilation processes which violate CP and lepton number. Importantly, a necessary one-loop contribution to the annihilation matrix element arises from absorptive ... More
Exact Algorithms for Maximum Clique: a computational studyJul 19 2012We investigate a number of recently reported exact algorithms for the maximum clique problem (MCQ, MCR, MCS, BBMC). The program code used is presented and critiqued showing how small changes in implementation can have a drastic effect on performance. ... More
Subdividing the cd-index of Eulerian PosetsApr 25 2016This thesis aims to give the reader an introduction and overview of the cd-index of a poset, as well as establish some new results. We give a combinatorial proof of Ehrenborg and Karu's cd-index subdivision decomposition for Gorenstein* complexes and ... More
Tachyons and Representations of SO(2,3)Oct 30 2002Jul 19 2004We describe an embedding of the Poincare Lie algebra into an extension of the Lie field of SO(2,3) (the anti-de Sitter group). We also describe higher dimensional analogs of this embedding, which connect SO(p,q) groups to their associated motion groups ... More
Bogomolov-Sommese vanishing on log canonical pairsOct 01 2012May 06 2013Let (X, D) be a projective log canonical pair. We show that for any natural number p, the sheaf (Omega_X^p(log D))^** of reflexive logarithmic p-forms does not contain a Weil divisorial subsheaf whose Kodaira-Iitaka dimension exceeds p. This generalizes ... More
A New Well-posed Nonlocal Perona-Malik Type EquationFeb 23 2007A modification of the Perona-Malik equation is proposed for which the local nonlinear diffusion term is replaced by a nonlocal term of slightly reduced ``strength''. The new equation is globally well-posed (in spaces of classical regularity) and possesses ... More
2-step nilpotent Lie groups arising from semisimple modulesJun 17 2008Every finite dimensional real representation of a compact real semisimple Lie algebra determines a metric 2-step nilpotent Lie algebra and a corresponding simply connected metric 2-step nilpotent Lie group N. We study the differential geometry of N using ... More
Sets with High Volume and Low PerimeterJul 14 2011In this paper, we consider a certain variation of the "isoperimetric problem" adopted for subsets of nonnegative integers. More specifically, we explore the sequence P(n) as described in OEIS A186053. We provide the first exact formulas for P(n) including ... More
Product formulas for the $5$-division points on the Tate normal form and the Rogers-Ramanujan continued fractionDec 19 2016Jun 11 2018Explicit formulas are proved for the $5$-torsion points on the Tate normal form $E_5$ of an elliptic curve having $(X,Y)=(0,0)$ as a point of order $5$. These formulas express the coordinates of points in $E_5[5] - \langle(0,0)\rangle$ as products of ... More
Single Exponential Approximation of Fourier TransformsDec 14 2005This article is concerned with a new method for the approximate evaluation of Fourier sine and cosine transforms. We develop and analyse a new quadrature rule for Fourier sine and cosine transforms involving transforming the integral to one over the entire ... More
Pointwise Convergence for Subsequences of Weighted AveragesNov 20 2009Sep 13 2011We prove that if $\mu_n$ are probability measures on $Z$ such that $\hat \mu_n$ converges to 0 uniformly on every compact subset of $(0,1)$, then there exists a subsequence $\{n_k\}$ such that the weighted ergodic averages corresponding to $\mu_{n_k}$ ... More
An L^1 Ergodic Theorem for Sparse Random SubsequencesDec 16 2008We prove an L^1 subsequence ergodic theorem for sequences chosen by independent random selector variables, thereby showing the existence of universally L^1-good sequences nearly as sparse as the set of squares. In the process, we prove that a certain ... More
The group of $K_1$-zero-cycles on the second generalized Severi-Brauer variety of an algebra of index 4Jun 18 2016Jun 22 2016In this manuscript, it is shown that the group of $K_1$-zero-cycles on the second generalized Severi-Brauer variety of an algebra $A$ of index 4 is given by elements of the group $K_1(A)$ together with a square-root of their reduced norm. Utilizing results ... More
Symplectic aspects of Aubry-Mather theoryJun 01 2005We prove that the so-called Aubry and Mane sets introduced by John Mather in Lagrangian dynamics are symplectic invariants. In order to do so, we introduce a barrier in phase space, and propose definitions of Aubry and Mane sets for non-convex Hamiltonian ... More
Still another approach to the braid orderingJun 24 2005We develop a new approach to the linear ordering of the braid group $B\_n$, based on investigating its restriction to the set $\Div(\Delta\_n^d)$ of all divisors of $\Delta\_n^d$ in the monoid $B\_\infty^+$, i.e., to positive $n$-braids whose normal form ... More
Efficient solutions to the braid isotopy problemMar 22 2007We describe the most efficient solutions to the word problem of Artin's braid group known so far, i.e., in other words, the most efficient solutions to the braid isotopy problem, including the Dynnikov method, which could be especially suitable for cryptographical ... More
Soft matter in hard confinement: phase transition thermodynamics, structure, texture, diffusion and flow in nanoporous media - topical reviewFeb 16 2015Spatial confinement in nanoporous media affects the structure, thermodynamics and mobility of molecular soft matter often markedly. This article reviews thermodynamic equilibrium phenomena, such as physisorption, capillary condensation, crystallisation, ... More
Cohomological Hasse principle for schemes over valuation rings of higher dimensional local fieldsMay 26 2016K. Kato's conjecture about the cohomological Hasse principle for regular connected schemes $\mathfrak X$ which are flat and proper over the complete discrete valuation rings $\mathcal O_N$ of higher local fields $F_N$ is proven. This generalizes the work ... More
Relative hyperbolicity and right-angled Coxeter groupsJan 21 2004We show that right-angled Coxeter groups are relatively hyperbolic in the sense defined by Farb, relative to a natural collection of rank-2 parabolic subgroups.
Automorphisms of Coxeter groupsOct 09 2003We compute Aut(W) for any even Coxeter group whose Coxeter diagram is connected, contains no edges labeled 2, and cannot be separated into more than 2 connected components by removing a single vertex. The description is given explicitly in terms of the ... More
Periodic points of algebraic functions and Deuring's class number formulaDec 11 2017Jan 01 2018The exact set of periodic points in $\overline{\mathbb{Q}}$ of the algebraic function $\widehat{F}(z)=(-1\pm \sqrt{1-z^4})/z^2$ is shown to consist of the coordinates of certain solutions $(x,y)=(\pi, \xi)$ of the Fermat equation $x^4+y^4=1$ in ring class ... More
Complete positive group presentationsNov 27 2001A combinatorial property of prositive group presentations, called completeness, is introduced, with an effective criterion for recognizing complete presentations, and an iterative method for completing an incomplete presentation. We show how to directly ... More
Groupes de GarsideNov 13 2001Define a Garside monoid to be a cancellative monoid where right and left lcm's exist and that satisfy additional finiteness assumptions, and a Garside group to be the group of fractions of a Garside monoid. The family of Garside groups contains the braid ... More
Towards Quality of Experience Determination for Video in Augmented Binocular Vision ScenariosJun 04 2014Mar 04 2015With the continuous growth in the consumer markets of mobile smartphones and increasingly in augmented reality wearable devices, several avenues of research investigate the relationships between the quality perceived by mobile users and the delivery mechanisms ... More
Multiwavelength Observations of Pulsar Wind NebulaeAug 27 2010The extended nebulae formed as pulsar winds expand into their surroundings provide information about the composition of the winds, the injection history from the host pulsar, and the material into which the nebulae are expanding. Observations from across ... More
High resolution X-ray observations of 3C 58Nov 10 2003As the presumed remnant of SN1181, 3C 58 houses one of the youngest known neutron stars in the Galaxy. The properties of this young pulsar and its associated wind nebula differ considerably from those of the Crab, and may well offer a more typical example ... More
Patching and Quillen K-TheoryJan 06 2014Mar 29 2014This paper provides an isomorphism $K_n (\mathscr{A}) \cong K_n (\mathscr{A}_1) \times_{K_n(\mathscr{A}_0)} K_n(\mathscr{A}_2)$ of $K$-groups, i.e., an exact sequence $0 \to K_n(\mathscr{A}) \to K_n(\mathscr{A}_1)\times K_n(\mathscr{A}_2) \to K_n(\mathscr{A}_0)$ ... More
Trajectories of Rubber Balloons used in Balloon Releases: Theory and ApplicationMar 10 2011Balloon releases are one of the main attractions of many fairs. Helium filled rubber balloons are released to carry postcards over preferably long distances. Although such balloons have been considered in atmospheric sciences and air safety analysis, ... More
On a Singular Integrodifferential Equation arising from a Linearised Free Surface ProblemDec 14 2005A problem of linear surface waves discussed by Forbes(1984) initially gave rise to a singular integrodifferential equation over the real line. We have been able to transform this integrodifferential equation into a linear second order differential equation ... More
Coxeter-like groups for groups of set-theoretic solutions of the Yang--Baxter equationMay 16 2013We attach with every finite, involutive, nondegenerate set-theoretic solution of the Yang--Baxter equation a finite group that plays for the associated structure group the role that a finite Coxeter group plays for the associated Artin--Tits group.
Using shifted conjugacy in braid-based cryptographySep 16 2006Conjugacy is not the only possible primitive for designing braid-based protocols. To illustrate this principle, we describe a Fiat--Shamir-style authentication protocol that be can be implemented using any binary operation that satisfies the left self-distributive ... More
Solutions of diophantine equations as periodic points of $p$-adic algebraic functions, IOct 17 2014Aug 30 2015Solutions of the quartic Fermat equation in ring class fields of odd conductor over quadratic fields $K=\mathbb{Q}(\sqrt{-d})$ with $-d \equiv 1$ (mod $8$) are shown to be periodic points of a fixed algebraic function $T(z)$ defined on the punctured disk ... More
Genus theory and the factorization of class equations over $\mathbb{F}_p$Sep 02 2014A new proof using genus theory is given of a Legendre symbol criterion for the class equation corresponding to the Hilbert class field of an imaginary quadratic field $\mathbb{Q}(\sqrt{D})$ to have a linear factor (mod $p$), when $p$ is an odd prime for ... More
On the origin of non self-gravitating filaments in the ISMJun 23 2013{Filaments are ubiquitous in the interstellar medium as recently emphasized by Herschel, yet their physical origin remains elusive} {It is therefore important to understand the physics of molecular clouds to investigate how filaments form and what is ... More
Formation of low-mass stars and brown dwarfsApr 23 2012These lectures attempt to expose the most important ideas, which have been proposed to explain the formation of stars with particular emphasis on the formation of brown dwarfs and low-mass stars. We first describe the important physical processes which ... More
Variation of the canonical height for a family of polynomialsMar 22 2010May 05 2011A theorem of Tate asserts that, for an elliptic surface E/X defined over a number field k, and a section P of E, there exists a divisor D on X such that the canonical height of the specialization of P to the fibre above t differs from the height of t ... More
On indecomposable trees in the boundary of Outer spaceFeb 16 2010May 25 2010Let $T$ be an $\mathbb{R}$-tree, equipped with a very small action of the rank $n$ free group $F_n$, and let $H \leq F_n$ be finitely generated. We consider the case where the action $F_n \curvearrowright T$ is indecomposable--this is a strong mixing ... More
Coherent Price Systems and Uncertainty-Neutral ValuationFeb 29 2012We consider fundamental questions of arbitrage pricing arising when the uncertainty model is given by a set of possible mutually singular probability measures. With a single probability model, essential equivalence between the absence of arbitrage and ... More
Testing Asteroseismology with red giants in eclipsing binary and multiple-star systemsNov 14 2013Red-giant stars are proving to be an incredible source of information for testing models of stellar evolution, as asteroseismology has opened up a window into their interiors. Such insights are a direct result of the unprecedented data from space missions ... More
SILEM : a new gaseous detector with integrated x-y readout planeJun 11 2007This works reports on gaseous detectors developments made in the frame of the EXO double-beta decay experiment. LEM (Large Electron Multiplication) are electron amplification grids based on GEM. They were developed in Neuchatel and showed remarquable ... More
Tautochrone and Brachistochrone Shape Solutions for Rocking Rigid BodiesApr 11 2016Rocking rigid bodies appear in several shapes in everyday life: As furniture like rocking chairs and rocking cradles or as toys like rocking horses or tilting dolls. The familiar rocking motion of these objects, a non-linear combination of a rigid rotation ... More
A Partial Proof of a Conjecture of DrisFeb 04 2016Euler showed that if an odd perfect number $N$ exists, it must consist of two parts $N=q^k n^2$, with $q$ prime, $q \equiv k \equiv 1 \pmod{4}$, and gcd$(q,n)=1$. Dris conjectured that $q^k < n$. We first show that $q<n$ for all odd perfect numbers. Afterwards, ... More
(Yet) Another Theoretical Model of ThinkingNov 08 2015Feb 15 2016This paper presents a theoretical, idealized model of the thinking process with the following characteristics: 1) the model can produce complex thought sequences and can be generalized to new inputs, 2) it can receive and maintain input information indefinitely ... More
Double Witt groupsAug 03 2015The difference between slice and doubly-slice knots is reflected in algebra by the difference between metabolic and hyperbolic Blanchfield linking forms. We exploit this algebraic distinction to refine the classical Witt group of linking forms by defining ... More
p-adic uniformization and the action of Galois on certain affine correspondencesApr 18 2016Given two monic polynomials f and g with coefficients in a number field K, and some a in K, we examine the action of the absolute Galois group of K on the directed graph of iterated preimages of a under the correspondence g(y)=f(x), assuming that deg(f)>deg(g) ... More
Towards Better Response Times and Higher-Quality Queries in Interactive Knowledge Base DebuggingSep 08 2016Many AI applications rely on knowledge encoded in a locigal knowledge base (KB). The most essential benefit of such logical KBs is the opportunity to perform automatic reasoning which however requires a KB to meet some minimal quality criteria such as ... More
Domain Variations for Moving Boundary ProblemsJul 19 2016Sep 15 2016In the past few decades maximal regularity theory has successfully been applied to moving boundary problems. The basic idea is to reduce the system with varying domains to one in a fixed domain. This is done by a transformation (the so-called Hanzawa ... More