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QUICker connection establishment with out-of-band validation tokensApr 12 2019QUIC is a secure transport protocol and aims to improve the performance of HTTPS traffic. It is a design goal of QUIC to reduce the delay overhead of its connection establishment. However, an initial handshake enforcing strict validation of the client's ... More

Enhanced Performance for the encrypted Web through TLS Resumption across HostnamesFeb 07 2019TLS can resume previous connections via abbreviated resumption handshakes that significantly decrease the delay and save expensive cryptographic operations. For that, cryptographic TLS state from previous connections is reused. TLS version 1.3 recommends ... More

Calculating the Habitable Zone of Multiple Star Systems (http://astro.twam.info/hz)Jan 03 2014We have developed a comprehensive methodology and an interactive website for calculating the habitable zone (HZ) of multiple star systems. Using the concept of spectral weight factor, as introduced in our previous studies of the calculations of HZ in ... More

Global analysis of generalized parton distributions -- collider kinematics --Dec 19 2013We utilize H1 and ZEUS data for exclusive electroproduction of photons, $\rho^0$- and $\phi$-mesons to access generalized parton distributions at small momentum fraction. To do so, we employ state-of-the art techniques, based on next-to-leading order ... More

Unsupervised Watertight Mesh Generation for Physics Simulation Applications Using Growing Neural Gas on Noisy Free-Form Object ModelsMar 02 2016Sep 03 2016We present a framework to generate watertight mesh representations in an unsupervised manner from noisy point clouds of complex, heterogeneous objects with free-form surfaces. The resulting meshes are ready to use in applications like kinematics and dynamics ... More

Limit multiplicities for principal congruence subgroups of GL(n) and SL(n)Aug 10 2012Mar 26 2014We study the limiting behavior of the discrete spectra associated to the principal congruence subgroups of a reductive group over a number field. While this problem is well understood in the cocompact case (i.e., when the group is anisotropic modulo the ... More

Permutation groups of prime degree, a quick proof of Burnside's theoremOct 14 2003A transitive permutation group of prime degree is doubly transitive or solvable. We give a direct proof of this theorem by Burnside which uses neither S-ring type arguments, nor representation theory.

Measurement of the single top quark and antiquark production cross sections in the $t$ channel and their ratio at 13 TeVJan 16 2019The electroweak production in the $t$ channel is the most dominant production mode of single top quarks at the LHC. The ratio of the cross sections of the top quark and antiquark production provides an insight into the inner structure of the proton and ... More

Asymptotics of automorphic spectra and the trace formulaSep 22 2015This paper is a survey article on the limiting behavior of the discrete spectrum of the right regular representation in $L^2(\Gamma\bs G)$ for a lattice $\Gamma$ in a reductive group $G$ over a number field. We discuss various aspects of the Weyl law, ... More

Physics and Signatures of the Quark - Gluon PlasmaOct 04 1994This is a critical review of the various observables that have been proposed to signal the change from dense hadronic matter to a quark-gluon plasma at high temperature or baryon density. I discuss current models of quark-gluon plasma formation in relativistic ... More

Colored ChaosAug 14 1994I review recent progress in our understanding of the basis of statistical models for hadronic reactions and of the mechanisms of thermalization in nonabelian gauge theories. (Invited talk given at the NATO Advanced Research Workshop on Hot Hadronic Matter: ... More

Physics of the Quark-Gluon PlasmaNov 20 1992Central nuclear collisions at energies far above 1 GeV/nucleon may provide for conditions, where the transition from highly excited hadronic matter into quark matter or quark-gluon plasma can be probed. Here I review our current understanding of the physical ... More

MATSuMoTo: The MATLAB Surrogate Model Toolbox For Computationally Expensive Black-Box Global Optimization ProblemsApr 16 2014MATSuMoTo is the MATLAB Surrogate Model Toolbox for computationally expensive, black-box, global optimization problems that may have continuous, mixed-integer, or pure integer variables. Due to the black-box nature of the objective function, derivatives ... More

Towards a fitting procedure to deeply virtual meson production -- the next-to-leading order case --Oct 21 2013Based on the collinear factorization approach, we present a comprehensive perturbative next-to-leading (NLO) analysis of deeply virtual meson production (DVMP). Our representation in conformal Mellin space can serve as basis for a global fitting procedure ... More

Parallelized Solution Method of the Three-dimensional Gravitational Potential on the Yin-Yang GridJun 12 2018Jul 12 2018We present a new method for solving the three-dimensional gravitational potential of a density field on the Yin-Yang grid. Our algorithm is based on a multipole decomposition and completely symmetric with respect to the two Yin-Yang grid patches. It is ... More

A Principled Approach to Grammars for Controlled Natural Languages and Predictive EditorsNov 15 2012Controlled natural languages (CNL) with a direct mapping to formal logic have been proposed to improve the usability of knowledge representation systems, query interfaces, and formal specifications. Predictive editors are a popular approach to solve the ... More

Codeco: A Grammar Notation for Controlled Natural Language in Predictive EditorsMar 29 2011Existing grammar frameworks do not work out particularly well for controlled natural languages (CNL), especially if they are to be used in predictive editors. I introduce in this paper a new grammar notation, called Codeco, which is designed specifically ... More

Status of SM calculations of b > s transitionsMar 21 2007May 22 2007We report recent progress in SM calculations of $b \to s$ transitions. We discuss the first NNLL prediction of the $\bar B \to X_s \gamma$ branching ratio, including important additional subtleties due to non-perturbative corrections and logarithmically-enhanced ... More

Equivariant spectral asymptotics for h-pseudodifferential operatorsNov 11 2013Dec 11 2014We prove equivariant spectral asymptotics for $ h$-pseudodifferential operators for compact orthogonal group actions generalizing results of El-Houakmi and Helffer (1991) and Cassanas (2006). Using recent results for certain oscillatory integrals with ... More

Quantum logic is undecidableJul 20 2016We investigate the first-order theory of closed subspaces of complex Hilbert spaces in the signature $(\lor,\perp,0)$, where `$\perp$' is orthogonality. Our main result is that already its purely implicational fragment is undecidable: there is no algorithm ... More

Retarded Functions in Noncommutative TheoriesDec 28 2004Apr 07 2005The perturbative approach to quantum field theory using retarded functions is extended to noncommutative theories. Unitarity as well as quantized equations of motion are studied and seen to cause problems in the case of space-time noncommutativity. A ... More

Violation of Remaining Lorentz Symmetry in the Approach of Time-Ordered Perturbation Theory to Space-Time NoncommutativityNov 12 2004Jan 20 2005We study remaining Lorentz symmetry, i.e. Lorentz transformations which leave the noncommutativity parameter $\theta^{\mu\nu}$ invariant, within the approach of time-ordered perturbation theory (TOPT) to space-time noncommutative theories. Their violation ... More

Interacting electrons in a magnetic field: mapping quantum mechanics to a classical ersatz-systemJul 09 2012Solving the quantum-mechanical many-body problem requires scalable computational approaches, which are rooted in a good understanding of the physics of correlated electronic systems. Interacting electrons in a magnetic field display a huge variety of ... More

Landau level broadening without disorder, non-integer plateaus without interactions - an alternative model of the quantum Hall effectJan 26 2006Jan 31 2006I review some aspects of an alternative model of the quantum Hall effect, which is not based on the presence of disorder potentials. Instead, a quantization of the electronic drift current in the presence of crossed electric and magnetic fields is employed ... More

Time-dependent approach to transport and scattering in atomic and mesoscopic physicsNov 14 2010Transport and scattering phenomena in open quantum-systems with a continuous energy spectrum are conveniently solved using the time-dependent Schrodinger equation. In the time-dependent picture, the evolution of an initially localized wave-packet reveals ... More

Categories of Fractions RevisitedMar 18 2008Sep 16 2011The theory of categories of fractions as originally developed by Gabriel and Zisman is reviewed in a pedagogical manner giving detailed proofs of all statements. A weakening of the category of fractions axioms used by Higson is discussed and shown to ... More

Logarithms, constructible functions and integration on non-archimedean models of the theory of the real field with restricted analytic functions with value group of finite archimedean rankMar 01 2018Mar 13 2018Given a model of the theory of the real field with restricted analytic functions such that its value group has finite archimedean rank we show how one can extend the restricted logarithm to a global logarithm with values in the polynomial ring over the ... More

On the Bloch-Kato conjecture for the Asai L-functionJul 02 2015Nov 28 2016Following Ribet's seminal 1976 paper there have been many results employing congruences between stable cuspforms and lifted forms to construct non-split extensions of Galois representations. We show how this strategy can be extended to construct elements ... More

A unified construction of semiring-homomorphic graph invariantsJan 04 2019Jan 22 2019It has recently been observed by Zuiddam that finite graphs form a preordered commutative semiring under the graph homomorphism preorder together with join and disjunctive product as addition and multiplication, respectively. This led to a new characterization ... More

Auslander Regularity of p-adic Distribution AlgebrasMar 15 2007Oct 01 2012Given a compact p-adic Lie group we show that its distribution algebra is Frechet-Stein with Auslander regular Banach algebras. As an application, we show that nonzero coadmissible modules coming from smooth or, more general, U(g)-finite representations ... More

Picard groups in $p$-adic Fourier theoryMar 27 2009Jun 25 2013Let $L$ be a proper finite extension of the field of $p$-adic numbers and let $o\subset L$ be its integers, viewed as an abelian locally $L$-analytic group. Let $\hat{o}$ be the rigid analytic group variety parametrizing the locally analytic characters ... More

On the support of Pollicott-Ruelle resonant states for Anosov flowsNov 26 2015Sep 15 2016We show that all generalized Pollicott-Ruelle resonant states of a topologically transitiv $C^\infty$-Anosov flow with an arbitrary $C^\infty$ potential, have full support.

Notes on Triangulated CategoriesJul 14 2014Jul 16 2014We give an elementary introduction to the theory of triangulated categories covering their axioms, homological algebra in triangulated categories, triangulated subcategories, and Verdier localization. We try to use a minimal set of axioms for triangulated ... More

Energy identity for approximations of harmonic maps from surfacesMay 31 2007Sep 11 2008We prove the energy identity for min-max sequences of the Sacks-Uhlenbeck and the biharmonic approximation of harmonic maps from surfaces into general target manifolds. The proof relies on Hopf-differential type estimates for the two approximations and ... More

A generalization of Strassen's Positivstellensatz and its application to large deviation theoryOct 19 2018Jan 04 2019Strassen's Positivstellensatz is a powerful but little known theorem on preordered commutative semirings satisfying a boundedness condition similar to Archimedeanicity. It characterizes the relaxed preorder induced by all monotone homomorphisms to $\mathbb{R}_+$ ... More

On locally analytic Beilinson-Bernstein localization and the canonical dimensionAug 07 2011Jun 25 2013Let G be a connected split reductive group over a p-adic field. In the first part of the paper we prove, under certain assumptions on G and the prime p, a localization theorem of Beilinson-Bernstein type for admissible locally analytic representations ... More

The average size of the kernel of a matrix and orbits of linear groups, II: dualityJul 03 2018Define a module representation to be a linear parameterisation of a collection of module homomorphisms over a ring. Generalising work of Knuth, we define duality functors indexed by the elements of the symmetric group of degree three between categories ... More

The average size of the kernel of a matrix and orbits of linear groupsApr 09 2017Apr 25 2018Let $\mathfrak{O}$ be a compact discrete valuation ring of characteristic zero. Given a module $M$ of matrices over $\mathfrak{O}$, we study the generating function encoding the average sizes of the kernels of the elements of $M$ over finite quotients ... More

Uniform persistence in a prey-predator model with a diseased predatorJan 21 2019Following the well-extablished mathematical approach to persistence and its recent developments we give a rigorous theoretical explanation to the numerical results obtained for a certain prey-predator model with functional response of Holling type II ... More

Homotopy (Pre-)Derivators of Cofibration Categories and Quasi-CategoriesDec 21 2017Apr 20 2018We prove that the homotopy prederivator of a cofibration category is equivalent to the homotopy prederivator of its associated quasi-category of frames, as introduced by Szumi\l{}o. We use this comparison result to deduce various abstract properties of ... More

Almost complex manifolds are (almost) complexMar 24 2019We analyze the differential relation corresponding to integrability of almost complex structures, reformulated as a directed immersion relation by Demailly and Gaussier. We prove that the relation has formal solutions up to complex dimension 77, and that, ... More

Multi-Task Learning for Argumentation MiningApr 23 2019Multi-task learning has recently become a very active field in deep learning research. In contrast to learning a single task in isolation, multiple tasks are learned at the same time, thereby utilizing the training signal of related tasks to improve the ... More

Global generalized solutions to a parabolic-elliptic Keller-Segel system with singular sensitivityMay 18 2017May 19 2017We investigate the parabolic-elliptic Keller-Segel model \begin{align*}\left\{\begin{array}{r@{\,}l@{\quad}l@{\quad}l@{\,}c} u_{t}&=\Delta u-\,\chi\nabla\!\cdot(\frac{u}{v}\nabla v),\ &x\in\Omega,& t>0,\\ 0&=\Delta v-\,v+u,\ &x\in\Omega,& t>0,\\ \frac{\partial ... More

Counterflow in EvacuationsOct 07 2011It is shown in this work that the average individual egress time and other performance indicators for egress of people from a building can be improved under certain circumstances if counterflow occurs. The circumstances include widely varying walking ... More

Nonabelian Gauge Theories: The Causal ApproachNov 11 1994May 02 1996We present the causal construction of perturbative Yang-Mills theories in four(3+1)-dimensional space-time. We work with free quantum fields throughout. The inductive causal method by Epstein and Glaser leads directly to a finite perturbation series and ... More

Electron drift orbits in crossed electromagnetic fields and the quantum Hall effectDec 28 2005The classical drift motion of electrons in crossed electric and magnetic fields provides an interesting example of a system with an on average constant velocity -- despite the presence of an electric field. This drift-velocity depends solely on the ratio ... More

A heuristic quantum theory of the integer quantum Hall effectSep 16 2005Dec 28 2005Contrary to common belief, the current emitted by a contact embedded in a two-dimensional electron gas (2DEG) is quantized in the presence of electric and magnetic fields. This observation suggests a simple, clearly defined model for the quantum current ... More

Polyhedral duality in Bell scenarios with two binary observablesFeb 01 2012Jun 18 2012For the Bell scenario with two parties and two binary observables per party, it is known that the no-signaling polytope is the polyhedral dual (polar) of the Bell polytope. Computational evidence suggests that this duality also holds for three parties. ... More

A Riemann-Hilbert correspondence for Cartier crystalsDec 01 2018For a variety $X$ separated over a perfect field of characteristic $p>0$ which admits an embedding into a smooth variety, we establish an anti-equivalence between the bounded derived categories of Cartier crystals on $X$ and constructible $\mathbb Z/p ... More

Antisymmetry of the stochastic order on all ordered metric spacesOct 16 2018In this short note, we prove that the stochastic order of Radon probability measures on any metric space is antisymmetric.

Transition probabilities and measurement statistics of postselected ensemblesMar 23 2010Jul 20 2010It is well-known that a quantum measurement can enhance the transition probability between two quantum states. Such a measurement operates after preparation of the initial state and before postselecting for the final state. Here we analyze this kind of ... More

Non-loose Legendrian spheres with trivial Contact Homology DGAFeb 16 2015Feb 13 2018Loose Legendrian n-submanifolds, for n at least 2, were introduced by Murphy and proved to be flexible in the h-principle sense: any two loose Legendrian submanifolds that are formally Legendrian isotopic are also actually Legendrian isotopic. Legendrian ... More

Hecke operators on period functions for $Γ_0(n)$Aug 23 2004May 23 2005Matrix representations of Hecke operators on classical holomorphical cusp forms and the corresponding period polynomials are well known. In this article we derive representations of Hecke operators for vector valued period functions for the congruence ... More

Hecke operators on period functions for the full modular groupJul 06 2004Feb 11 2005Matrix representations of Hecke operators on classical holomorphical cusp forms and corresponding period polynomials are well known. In this article we define Hecke operators on period functions and show that they correspond to the Hecke operators on ... More

Regularizing Feynman path integrals using the generalized Kontsevich-Vishik traceMar 09 2017A fully regulated definition of Feynman's path integral is presented here. The proposed re-formulation of the path integral coincides with the familiar formulation whenever the path integral is well-defined. In particular, it is consistent with respect ... More

Hecke algebras and affine flag varieties in characteristic pJan 24 2015Oct 02 2015Let G be a split semi-simple p-adic group and let H be its Iwahori-Hecke algebra with coefficients in the algebraic closure k of the finite field with p elements. Let F be the affine flag variety over k associated with G. We show, in the simply connected ... More

A Conjectural Algorithm for Simple Characters of Algebraic GroupsSep 08 2017We describe an algorithm, which - given the characters of tilting modules and assuming that Donkin's tilting conjecture is true - computes the characters of simple modules for an algebraic group in any characteristic.

Analytic vectors in continuous p-adic representationsNov 13 2007Oct 01 2012Given a compact p-adic Lie group G over a finite unramified extension L/Q_p let G_0 be the product over all Galois conjugates of G. We construct an exact and faithful functor from admissible G-Banach space representations to admissible locally L-analytic ... More

A Characterization of Effective Resistance MetricsOct 04 2017Jun 11 2018We produce a characterization of finite metric spaces which are given by the effective resistance of a graph. This characterization is applied to the more general context of resistance metrics defined by Kigami. A countably infinite resistance metric ... More

The fiber dimension of a graphJan 18 2016Graphs on integer points of polytopes whose edges come from a set of allowed differences are studied. It is shown that any simple graph can be embedded in that way. The minimal dimension of such a representation is the fiber dimension of the given graph. ... More

An Eisenstein ideal for imaginary quadratic fields and the Bloch-Kato conjecture for Hecke charactersJan 05 2007For certain algebraic Hecke characters chi of an imaginary quadratic field F we define an Eisenstein ideal in a p-adic Hecke algebra acting on cuspidal automorphic forms of GL_2/F. By finding congruences between Eisenstein cohomology classes (in the sense ... More

Knot contact homology and open Gromov-Witten theoryNov 16 2017Knot contact homology studies symplectic and contact geometric properties of conormals of knots in 3-manifolds using holomorphic curve techniques. It has connections to both mathematical and physical theories. On the mathematical side, we review the theory, ... More

Boundedness in a Keller-Segel system with external signal productionJul 27 2015We study the Neumann initial-boundary problem for the chemotaxis system \begin{align*} \left\{\begin{array}{c@{\,}l@{\quad}l@{\,}c} u_{t}&=\Delta u-\nabla\!\cdot(u\nabla v),\ &x\in\Omega,& t>0,\\ v_{t}&=\Delta v-v+u+f(x,t),\ &x\in\Omega,& t>0,\\ \frac{\partial ... More

Nonlocality with less ComplementarityJun 20 2011Feb 01 2012In quantum mechanics, nonlocality (a violation of a Bell inequality) is intimately linked to complementarity, by which we mean that consistently assigning values to different observables at the same time is not possible. Nonlocality can only occur when ... More

Beyond Bell's Theorem: Correlation ScenariosJun 22 2012Sep 02 2012Bell's Theorem witnesses that the predictions of quantum theory cannot be reproduced by theories of local hidden variables in which observers can choose their measurements independently of the source. Working out an idea of Branciard, Rosset, Gisin and ... More

Instrument Control at the FRM-II using TACO and NICOSOct 20 2002Oct 22 2002At the new neutron source FRM--II in Garching, Germany, the TACO control system, originally developed at the ESRF in Grenoble, France is used for instrument control purposes. TACO provides an object oriented, distributed control system including a clearly ... More

On the Bloch-Kato conjecture for the Asai L-functionJul 02 2015Following Ribet's seminal 1976 paper there have been many results employing congruences between stable cuspforms and lifted forms to construct non-split extensions of Galois representations. We show how this strategy can be extended to construct elements ... More

On unitary deformations of smooth modular representationsDec 20 2009Oct 15 2012Let G be a locally analytic group. We use deformation theory and Emerton's 'augmented' Iwasawa modules to study the possible liftings of a given absolutely irreducible smooth modular representation of G to a unitary Banach space representation. Final ... More

Decomposition of tensor products involving a Steinberg moduleJun 20 2016Feb 08 2018We study the decomposition of tensor products between a Steinberg module and a costandard module, both as a module for the algebraic group $G$ and when restricted to either a Frobenius kernel $G_r$ or a finite Chevalley group $G(\mathbb{F}_q)$. In all ... More

On permutations with decidable cyclesDec 15 2016Recursive permutations whose cycles are the classes of a decidable equivalence relation are studied; the set of these permutations is called $\mathrm{Perm}$, the group of all recursive permutations $\mathcal{G}$. Multiple equivalent computable representations ... More

Analysis of the first variation and a numerical gradient flow for integral Menger curvatureAug 27 2014In this thesis, we consider the knot energy "integral Menger curvature" which is the triple integral over the inverse of the classic circumradius of three distinct points on the given knot to the power $p\in [2,\infty)$. We prove the existence of the ... More

Verma modules over p-adic Arens-Michael envelopes of reductive Lie algebrasAug 23 2010Jun 25 2013Let K be a locally compact nonarchimedean field, g a split reductive Lie algebra over K and U(g) its universal enveloping algebra. We study the category C_g of coadmissible modules over the nonarchimedean Arens-Michael envelope of U(g). Let p be a parabolic ... More

Slice theorem for Fréchet group actions and covariant symplectic field theoryMay 09 2014A general slice theorem for the action of a Fr\'echet Lie group on a Fr\'echet manifolds is established. The Nash-Moser theorem provides the fundamental tool to generalize the result of Palais to this infinite-dimensional setting. The presented slice ... More

Resonance chains and geometric limits on Schottky surfacesMar 28 2014Resonance chains have been observed in many different physical and mathematical scattering problems. Recently numerical studies linked the phenomenon of resonances chains to an approximate clustering of the length spectrum on integer multiples of a base ... More

Eventual smoothness of generalized solutions to a singular chemotaxis-Stokes systemMay 17 2017We study the chemotaxis-fluid system \begin{align*} \left\{ \begin{array}{r@{\,}c@{\,}c@{\ }l@{\quad}l@{\quad}l@{\,}c} n_{t}&+&u\cdot\!\nabla n&=\Delta n-\nabla\!\cdot(\frac{n}{c}\nabla c),\ &x\in\Omega,& t>0, c_{t}&+&u\cdot\!\nabla c&=\Delta c-nc,\ &x\in\Omega,& ... More

The Stokes limit in a three-dimensional chemotaxis-Navier-Stokes systemFeb 17 2019We consider initial-boundary value problems for the $\kappa$-dependent family of chemotaxis-(Navier--)Stokes systems \begin{align*} \left\{ \begin{array}{r@{\,}c@{\,}c@{\ }l@{\quad}l@{\quad}l@{\,}c} n_{t}&+&u\cdot\!\nabla n&=\Delta n-\nabla\!\cdot(n\nabla ... More

Global solvability of chemotaxis-fluid systems with nonlinear diffusion and matrix-valued sensitivities in three dimensionsJul 06 2018In this work we extend a recent result to chemotaxis fluid systems which include matrix-valued sensitivity functions $S(x,n,c):\Omega\times[0,\infty)^2\to\mathbb{R}^{3\times3}$ in addition to the porous medium type diffusion, which were discussed in the ... More

Global very weak solutions to a chemotaxis-fluid system with nonlinear diffusionDec 01 2017Jun 06 2018We consider the chemotaxis-fluid system \begin{align}\label{star}\tag{$\diamondsuit$} \left\{ \begin{array}{r@{\,}c@{\,}c@{\ }l@{\quad}l@{\quad}l@{\,}c} n_{t}&+&u\cdot\!\nabla n&=\Delta n^m-\nabla\!\cdot(n\nabla c),\ &x\in\Omega,& t>0,\\ c_{t}&+&u\cdot\!\nabla ... More

News on PenguinsNov 09 2011We summarize recent theoretical developments in the field of radiative and semileptonic penguin decays.

Two interacting electrons in a magnetic field: comparison of semiclassical, quantum, and variational solutionsSep 30 2010The quantum mechanical many-body problem is rarely analytically solvable. One notable exception is the case of two electrons interacting via a Coulomb potential in a uniform magnetic field. The motion is confined to a two-dimensional plane, which is commonly ... More

Global existence without decay for quadratic Klein-Gordon equationsSep 07 2012Sep 19 2012The Cauchy problem for quadratic Klein-Gordon systems is considered in two spatial dimensions and higher under a suitable non-resonance condition on the masses, including the main case of equal masses. A global well-posedness and scattering result is ... More

Divisors on Projective Hibi VarietiesJun 08 2015We compute the divisor class group and the Picard group of projective varieties with Hibi rings as homogeneous coordinate rings. These varieties are precisely the toric varieties associated to order polytopes. We use tools from the theory of toric varieties ... More

Computing topological zeta functions of groups, algebras, and modules, IISep 17 2014Building on our previous work (arXiv:1405.5711), we develop the first practical algorithm for computing topological zeta functions of nilpotent groups, non-associative algebras, and modules. While we previously depended upon non-degeneracy assumptions, ... More

Blow-up of weak solutions to a chemotaxis system under influence of an external chemoattractantOct 24 2015We study nonnnegative radially symmetric solutions of the parabolic-elliptic Keller-Segel whole space system \begin{align*} \left\{\begin{array}{c@{\,}l@{\quad}l@{\,}c} u_{t}&=\Delta u-\nabla\!\cdot(u\nabla v),\ &x\in\mathbb{R}^n,& t>0,\\ 0 &=\Delta v+u+f(x),\ ... More

Multi-Directional Flow as Touch-Stone to Assess Models of Pedestrian DynamicsDec 31 2012For simulation models of pedestrian dynamics there are always the issues of calibration and validation. These are usually done by comparing measured properties of the dynamics found in observation, experiments and simulation in certain scenarios. For ... More

Fenchel-Nielsen Coordinates for Maximal RepresentationsApr 03 2012We develop Fenchel-Nielsen coordinates for representations of surface groups into Sp(2n,R) with maximal Toledo invariant. Analogous to classical Fenchel-Nielsen coordinates on the Teichm\"uller space they consist of a parametrization of representations ... More

Constraining the supersaturation density equation of state from core-collapse supernova simulations - Excluded volume extension of the baryonsApr 06 2016In this article the role of the supersaturation density equation of state (EOS) is explored in simulations of failed core-collapse supernova explosions. Therefore the nuclear EOS is extended via a one-parameter excluded volume description for baryons, ... More

A1-homotopy invariants of topological Fukaya categories of surfacesMay 26 2015Apr 25 2016We provide an explicit formula for localizing $A^1$-homotopy invariants of topological Fukaya categories of marked surfaces. Following a proposal of Kontsevich, this differential $\mathbb Z$-graded category is defined as global sections of a constructible ... More

Running Identical Threads in C-Slow Retiming based Designs for Functional Failure DetectionFeb 04 2015This paper shows the usage of C-Slow Retiming (CSR) in safety critical and low power applications. CSR generates C copies of a design by reusing the given logic resources in a time sliced fashion. When all C design copies are stimulated with the same ... More

On the capacity of the dither-quantized Gaussian channelJan 27 2014Apr 25 2014This paper studies the capacity of the peak-and-average-power-limited Gaussian channel when its output is quantized using a dithered, infinite-level, uniform quantizer of step size $\Delta$. It is shown that the capacity of this channel tends to that ... More

Rational Symplectic Field Theory over Z_2 for exact Lagrangian cobordismsDec 01 2006We construct a version of rational Symplectic Field Theory for pairs $(X,L)$, where $X$ is an exact symplectic manifold, where $L\subset X$ is an exact Lagrangian submanifold with components subdivided into $k$ subsets, and where both $X$ and $L$ have ... More

Computing topological zeta functions of groups, algebras, and modules, IMay 22 2014We develop techniques for computing zeta functions associated with nilpotent groups, not necessarily associative algebras, and modules, as well as Igusa-type zeta functions. At the heart of our method lies an explicit convex-geometric formula for a class ... More

$R$-analytic functionsFeb 23 2015Apr 04 2016We introduce the notion of $R$-analytic functions. These are definable in an o-minimal expansion of a real closed field $R$ and are locally the restriction of a $K$-differentiable function (defined by Peterzil and Starchenko) where $K=R[\sqrt{-1}]$ is ... More

Sublinear signal production in a two-dimensional Keller-Segel-Stokes systemFeb 01 2016We study the chemotaxis-fluid system \begin{align*} \left\{\begin{array}{r@{\,}l@{\quad}l@{\,}c} n_{t}&=\Delta n-\nabla\!\cdot(n\nabla c)-u\cdot\!\nabla n,\ &x\in\Omega,& t>0,\\ c_{t}&=\Delta c-c+f(n)-u\cdot\!\nabla c,\ &x\in\Omega,& t>0,\\ u_{t}&=\Delta ... More

Regular homotopy and total curvatureOct 17 2003Mar 10 2009We consider properties of the total absolute geodesic curvature functional on circle immersions into a Riemann surface. In particular, we study its behavior under regular homotopies, its infima in regular homotopy classes, and the homotopy types of spaces ... More

On the ring of invariants of ordinary quartic curves in characteristic 2May 04 2004In this article a complete set of invariants for ordinary quartic curves in characteristic 2 is computed.

Pseudogaps in strongly interacting Fermi gasesJan 17 2017A central challenge in modern condensed matter physics is developing the tools for understanding nontrivial yet unordered states of matter. One important idea to emerge in this context is that of a "pseudogap": the fact that under appropriate circumstances ... More

Dispersion and wavefunction symmetry in cold atoms experiencing artificial gauge fieldsNov 02 2011We analyze the single particle quantum mechanics of an atom whose dispersion is modified by spin orbit coupling to Raman lasers. We calculate how the novel dispersion leads to unusual single particle physics. We focus on the symmetry of the ground state ... More

Wigner Crystallization in inhomogeneous one dimensional wiresOct 29 2004Apr 22 2005We explore the theory of electrons confined by one dimensional power law potentials. We calculate the density profile in the high density electron gas, the low density Wigner crystal, and the intermediate regime. We extract the momentum space wavefunction ... More

Crowdbreaks: Tracking Health Trends using Public Social Media Data and CrowdsourcingMay 14 2018In the past decade, tracking health trends using social media data has shown great promise, due to a powerful combination of massive adoption of social media around the world, and increasingly potent hardware and software that enables us to work with ... More