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Results for "Jan-Niklas Schmidt"

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Transient supersolid properties in an array of dipolar quantum dropletsJan 23 2019Mar 08 2019We study theoretically and experimentally the emergence of supersolid properties in a dipolar Bose-Einstein condensate. The theory reveals a ground state phase diagram with three distinct regimes - a regular Bose-Einstein condensate, incoherent and coherent ... More
Anisotropic Superfluid Behavior of a Dipolar Bose-Einstein CondensateApr 12 2018Jul 18 2018We present transport measurements on a dipolar superfluid using a Bose-Einstein condensate of Dy-162 with strong magnetic dipole-dipole interactions. By moving an attractive laser beam through the condensate we observe an anisotropy in superfluid flow. ... More
The low-energy Goldstone mode in a trapped dipolar supersolidJun 11 2019A supersolid is a counter-intuitive state of matter that combines the frictionless flow of a superfluid with the crystal-like periodic density modulation of a solid. Since the first prediction in the 1950s, experimental efforts to realize this state have ... More
Quantum Simulation Logic, Oracles, and the Quantum AdvantageMay 13 2019Query complexity is a common tool for comparing quantum and classical computation, and it has produced many examples of how quantum algorithms differ from classical ones. Here we investigate in detail the role that oracles play for the advantage of quantum ... More
Realization of Shor's Algorithm at Room TemperatureJun 10 2017Shor's algorithm can find prime factors of a large number more efficiently than any known classical algorithm. Understanding the properties that gives the speedup is essential for a general and scalable construction. Here we present a realization of Shor's ... More
Magnetic catalysis and inverse magnetic catalysis in QCDFeb 27 2015May 13 2015We investigate the effects of strong magnetic fields on the QCD phase structure at vanishing density by solving the gluon and quark gap equations, and by studying the dynamics of the quark scattering with the four-fermi coupling. The chiral crossover ... More
Efficient classical simulation of the Deutsch-Jozsa and Simon's algorithmsAug 20 2015Mar 05 2018A long-standing aim of quantum information research is to understand what gives quantum computers their advantage. This requires separating problems that need genuinely quantum resources from those for which classical resources are enough. Two examples ... More
Efficient classical simulation of the Deutsch-Jozsa algorithmJun 15 2015Sep 10 2015In 1985, David Deutsch challenged the Church-Turing thesis by stating that his quantum model of computation "could, in principle, be built and would have many remarkable properties not reproducible by any Turing machine". While this is thought to be true ... More
Quantum correlations in dilute dipolar quantum droplets beyond the extended Gross-Pitaevskii equationApr 23 2019Dipolar quantum droplets are exotic quantum objects that are self-bound due to the subtle balance of attraction, repulsion and quantum correlations. Here we present a systematic study of the critical atom number of these self-bound droplets, comparing ... More
Developing Artificial Herders Using JasonDec 31 2009This paper gives an overview of a proposed strategy for the "Cows and Herders" scenario given in the Multi-Agent Programming Contest 2009. The strategy is to be implemented using the Jason platform, based on the agent-oriented programming language Agent-Speak. ... More
Multi-Agent Programming Contest 2010 - The Jason-DTU TeamOct 01 2010We provide a brief description of the Jason-DTU system, including the methodology, the tools and the team strategy that we plan to use in the agent contest.
One-Loop Superconformal and Yangian Symmetries of Scattering Amplitudes in N=4 Super Yang-MillsFeb 09 2010Apr 21 2010Recently it has been argued that tree-level scattering amplitudes in N=4 Yang-Mills theory are uniquely determined by a careful study of their superconformal and Yangian symmetries. However, at one-loop order these symmetries are known to become anomalous ... More
Integrability of Smooth Wilson Loops in N=4 SuperspaceSep 17 2015Nov 20 2015We perform a detailed study of the Yangian symmetry of smooth supersymmetric Maldacena-Wilson loops in planar N=4 super Yang-Mills theory. This hidden symmetry extends the global superconformal symmetry present for these observables. A gauge-covariant ... More
Master formula for one-loop renormalization of bosonic SMEFT operatorsApr 16 2019Using background-field method and super-heat-kernel expansion, we derive a master formula for the one-loop UV divergences of the bosonic dimension-6 operators in Standard Model Effective Field Theory (SMEFT). This approach reduces the calculation of all ... More
Existence and uniqueness of global classical solutions to a two species cancer invasion haptotaxis modelApr 26 2017We consider a haptotaxis cancer invasion model that includes two families of cancer cells. Both families, migrate on the extracellular matrix and proliferate. Moreover the model describes an epithelial-to-mesenchymal-like transition between the two families, ... More
Solving $k$-means on High-dimensional Big DataFeb 15 2015May 28 2015In recent years, there have been major efforts to develop data stream algorithms that process inputs in one pass over the data with little memory requirement. For the $k$-means problem, this has led to the development of several $(1+\varepsilon)$-approximations ... More
Particle-in-Cell/Test-Particle Simulations of Technological Plasmas: Sputtering Transport in Capacitive Radio Frequency DischargesJul 14 2016The paper provides a tutorial to the conceptual layout of a self-consistently coupled Particle-In-Cell/Test-Particle model for the kinetic simulation of sputtering transport in capacitively coupled plasmas at low gas pressures. It explains when a kinetic ... More
Sparse Proteomics Analysis - A compressed sensing-based approach for feature selection and classification of high-dimensional proteomics mass spectrometry dataJun 11 2015Nov 26 2016Background: High-throughput proteomics techniques, such as mass spectrometry (MS)-based approaches, produce very high-dimensional data-sets. In a clinical setting one is often interested in how mass spectra differ between patients of different classes, ... More
Gaussian covariance matrices for anisotropic galaxy clustering measurementsSep 14 2015Jan 07 2016Measurements of the redshift-space galaxy clustering have been a prolific source of cosmological information in recent years. Accurate covariance estimates are an essential step for the validation of galaxy clustering models of the redshift-space two-point ... More
Normal-state properties of the antiperovskite oxide Sr$_{3-x}$SnO revealed by $^{119}$Sn-NMRSep 25 2018We have performed $^{119}$Sn-NMR measurements on the antiperovskite oxide superconductor Sr$_{3-x}$SnO to investigate how its normal state changes with the Sr deficiency. A two-peak structure was observed in the NMR spectra of all the measured samples. ... More
Superconductivity in the antiperovskite Dirac-metal oxide Sr$_3$SnOApr 21 2016Feb 24 2017Oxides with perovskite-based structures have been known as essential materials for fascinating phenomena such as high-temperature and unconventional superconductivity. Discoveries of these oxide superconductors have driven the science community to vastly ... More
A generic method for equipping arbitrary rf discharge simulation frameworks with external lumped element circuitsFeb 06 2019External electric circuits attached to radio-frequency plasma discharges are essential for the power transfer into the discharge and are, therefore, a key element for plasma operation. Many plasma simulations, however, simplify or even neglect the external ... More
Hadronic Production of Gamma Rays and Starburst GalaxiesOct 01 2008The Milky Way has been estabished to emit gamma rays. These gamma rays are presumably dominated by decays of neutral pions, although inverse Compton scatterings and bremsstrahlung also contribute. It is plausible that other galaxies can be diffuse sources ... More
The su(2|3) Undynamic Spin ChainJul 01 2008Apr 17 2009The integrable spin chain found in perturbative planar N=4 supersymmetric gauge theory is dynamic. Here we propose a reformulation which removes the dynamic effects in order to make the model more accessible to an algebraic treatment.
Higher-Loop Integrability in N=4 Gauge TheorySep 14 2004Oct 28 2004The dilatation operator measures scaling dimensions of local operator in a conformal field theory. Algebraic methods of constructing the dilatation operator in four-dimensional N=4 gauge theory are reviewed. These led to the discovery of novel integrable ... More
The Dilatation Operator of N=4 Super Yang-Mills Theory and IntegrabilityJul 30 2004Oct 22 2005The dilatation generator measures the scaling dimensions of local operators in a conformal field theory. In this thesis we consider the example of maximally supersymmetric gauge theory in four dimensions and develop and extend techniques to derive, investigate ... More
Review of AdS/CFT Integrability, Chapter VI.1: Superconformal SymmetryDec 17 2010Mar 20 2011Aspects of the D=4, N=4 superconformal symmetry relevant to the AdS/CFT duality and integrability are reviewed. These include the Lie superalgebra psu(2,2|4), its representations, conformal transformations and correlation functions in N=4 super Yang-Mills ... More
On the Scattering Phase for AdS_5 x S^5 StringsJun 22 2006Feb 05 2007We propose a phase factor of the worldsheet S-matrix for strings on AdS_5 x S^5 apparently solving Janik's crossing relation.
The su(2|3) Dynamic Spin ChainOct 28 2003Dec 09 2003The complete one-loop, planar dilatation operator of the N=4 superconformal gauge theory was recently derived and shown to be integrable. Here, we present further compelling evidence for a generalisation of this integrable structure to higher orders of ... More
The Complete One-Loop Dilatation Operator of N=4 Super Yang-Mills TheoryJul 01 2003Feb 27 2011We continue the analysis of hep-th/0303060 in the one-loop sector and present the complete psu(2,2|4) dilatation operator of N=4 Super Yang-Mills theory. This operator generates the matrix of one-loop anomalous dimensions for all local operators in the ... More
The Analytic Bethe Ansatz for a Chain with Centrally Extended su(2|2) SymmetryOct 09 2006Jan 02 2007We investigate the integrable structure of spin chain models with centrally extended su(2|2) and psu(2,2|4) symmetry. These chains have their origin in the planar AdS/CFT correspondence, but they also contain the one-dimensional Hubbard model as a special ... More
An SU(1|1)-Invariant S-Matrix with Dynamic RepresentationsNov 01 2005Nov 07 2005The spin chains originating from large-N conformal gauge theories are of a special kind: The Hamiltonian is not invariant under the symmetry algebra, it is rather a part of it. This leads to interesting properties within the asymptotic Bethe ansatz. Here ... More
Spin Chain for Quantum StringsSep 03 2004Sep 14 2004We review and compare the integrable structures in N=4 gauge theory and string theory on AdS5xS5. Recently, Bethe ansaetze for gauge theory/weak coupling and string theory/strong coupling were proposed to describe scaling dimensions in the su(2) subsector. ... More
The su(2|2) Dynamic S-MatrixNov 07 2005Sep 19 2006We derive and investigate the S-matrix for the su(2|3) dynamic spin chain and for planar N=4 super Yang-Mills. Due to the large amount of residual symmetry in the excitation picture, the S-matrix turns out to be fully constrained up to an overall phase. ... More
T-Duality, Dual Conformal Symmetry and Integrability for Strings on AdS_5 x S^5Mar 03 2009In recent years two intriguing observations have been made for N=4 super Yang-Mills theory and for superstrings on AdS5xS5: In the planar limit the computation of the spectrum is vastly simplified by the apparent integrability of the models. Furthermore, ... More
BMN Operators and Superconformal SymmetryNov 05 2002Mar 17 2003Implications of N=4 superconformal symmetry on Berenstein-Maldacena-Nastase (BMN) operators with two charge defects are studied both at finite charge J and in the BMN limit. We find that all of these belong to a single long supermultiplet explaining a ... More
Conditional Densities and Simulations of Inhomogeneous Poisson Point Processes: The R package "IPPP"Jan 30 2019May 20 2019A number of numeric approaches to simulate Poisson point processes with arbitrary event rates are presented and implemented for R. They include the simulation of the number of points and their location as well as the determination of conditional probability ... More
Study of Higgs Production in Fermionic Decay Channels at CMSJul 22 2013In these proceedings to the LHCP conference 2013 results are presented on the study of the Higgs-like particle at a mass of 125 GeV decaying into final states consisting of either $\tau^+\tau^-$, or a $b\bar{b}$ quark pair, based on the full statistics ... More
The Classical Trigonometric r-Matrix for the Quantum-Deformed Hubbard ChainFeb 05 2010Apr 03 2011The one-dimensional Hubbard model is an exceptional integrable spin chain which is apparently based on a deformation of the Yangian for the superalgebra gl(2|2). Here we investigate the quantum-deformation of the Hubbard model in the classical limit. ... More
Higher loops, integrability and the near BMN limitAug 11 2003In this note we consider higher-loop contributions to the planar dilatation operator of N=4 SYM in the su(2) subsector of two complex scalar fields. We investigate the constraints on the form of this object due to interactions of two excitations in the ... More
The S-Matrix of AdS/CFT and Yangian SymmetryApr 03 2007Mar 27 2008We review the algebraic construction of the S-matrix of AdS/CFT. We also present its symmetry algebra which turns out to be a Yangian of the centrally extended su(2|2) superalgebra.
Towards Verifying Safety Properties of Real-Time Probabilistic SystemsApr 03 2014Using probabilities in the formal-methods-based development of safety-critical software has quickened interests in academia and industry. We address this area by our model-driven engineering method for reactive systems SPACE and its tool-set Reactive ... More
Solutions of martingale problems for Lévy-type operators and stochastic differential equations driven by Lévy processes with discontinuous coefficientsAug 08 2012We show the existence of L\'evy-type stochastic processes in one space dimension with characteristic triplets that are either discontinuous at thresholds, or are stable-like with stability index functions for which the closures of the discontinuity sets ... More
On Vertex- and Empty-Ply Proximity DrawingsAug 30 2017Sep 07 2017We initiate the study of the vertex-ply of straight-line drawings, as a relaxation of the recently introduced ply number. Consider the disks centered at each vertex with radius equal to half the length of the longest edge incident to the vertex. The vertex-ply ... More
Scaling provable adversarial defensesMay 31 2018Nov 21 2018Recent work has developed methods for learning deep network classifiers that are provably robust to norm-bounded adversarial perturbation; however, these methods are currently only possible for relatively small feedforward networks. In this paper, in ... More
Application-Agnostic Offloading of Packet ProcessingApr 01 2019As network speed increases, servers struggle to serve all requests directed at them. This challenge is rooted in a partitioned data path where the split between the kernel space networking stack and user space applications induces overheads. To address ... More
Comment on "Motion of a helical vortex filament in superfluid 4He under the extrinsic form of the local induction approximation"Oct 01 2013We comment on the paper by Van Gorder ["Motion of a helical vortex filament in superfluid ${}^4$He under the extrinsic form of the local induction approximation", Phys. Fluids 25, 085101 (2013)]. We point out that the flow of the normal fluid component ... More
Construction of Lax Connections by ExponentiationJul 13 2012We propose a method for constructing the Lax connection of two-dimensional relativistic integrable sigma models on coset spaces by means of exponentiation of a suitable operator. We derive a simple quadratic relation that this operator must satisfy for ... More
Yangian Algebra and Correlation Functions in Planar Gauge TheoriesApr 24 2018Jul 02 2018In this work we consider colour-ordered correlation functions of the fields in integrable planar gauge theories such as N=4 supersymmetric Yang-Mills theory with the aim to establish Ward-Takahashi identities corresponding to Yangian symmetries. To this ... More
Optimization of electron pumping by harmonic mixingDec 21 2010Mar 22 2011For a symmetric bridge coupled to infinite leads, in the presence of a dipole-coupled external ac-field with harmonic mixing, we solve the Schr\"odinger equation in the time-domain using open boundary conditions as well as in the energy-domain using Floquet ... More
Gravity duals for logarithmic conformal field theoriesDec 30 2009Mar 09 2010Logarithmic conformal field theories with vanishing central charge describe systems with quenched disorder, percolation or dilute self-avoiding polymers. In these theories the energy momentum tensor acquires a logarithmic partner. In this talk we address ... More
Long-Range PSU(2,2|4) Bethe Ansaetze for Gauge Theory and StringsApr 25 2005Sep 26 2005We generalize various existing higher-loop Bethe ansaetze for simple sectors of the integrable long-range dynamic spin chain describing planar N=4 Super Yang-Mills Theory to the full psu(2,2|4) symmetry and, asymptotically, to arbitrary loop order. We ... More
Optimal Topological Test for Degeneracies of Real HamiltoniansOct 03 2003Jan 09 2004We consider adiabatic transport of eigenstates of real Hamiltonians around loops in parameter space. It is demonstrated that loops that map to nontrivial loops in the space of eigenbases must encircle degeneracies. Examples from Jahn-Teller theory are ... More
Graded and Geometric Parabolic Induction for Category $\mathcal{O}$Mar 01 2016Sep 13 2018We prove that the parabolic induction functor on BGG-category $\mathcal{O}$ associated to a complex reductive Lie algebra is gradable, that is, lifts to graded category $\mathcal{O}$ as constructed by Beilinson-Ginzburg-Soergel. Graded category $\mathcal{O}$ ... More
Searching for degeneracies of real Hamiltonians using homotopy classification of loops in SO($n$)Jun 15 2004Jan 25 2005Topological tests to detect degeneracies of Hamiltonians have been put forward in the past. Here, we address the applicability of a recently proposed test [Phys. Rev. Lett. {\bf 92}, 060406 (2004)] for degeneracies of real Hamiltonian matrices. This test ... More
Coulomb Branches of Star-Shaped QuiversAug 15 2018Dec 07 2018We study the Coulomb branches of 3d N=4 `star-shaped' quiver gauge theories and their deformation quantizations, by applying algebraic techniques that have been developed in the mathematics and physics literature over the last few years. The algebraic ... More
Finite-frequency noise of interacting single-electron emitters: spectroscopy with higher noise harmonicsMay 08 2018We derive the symmetrized current-noise spectrum of a quantum dot, which is weakly tunnel-coupled to an electron reservoir and driven by a slow time-dependent gate voltage. This setup can be operated as an on-demand emitter of single electrons into a ... More
A flexible multidimensional rectangular mesh administration and refinement technique with application in cancer invasion modelsJun 19 2017We present a mesh-structure data administration technique for the bookkeeping of adaptive mesh refinement, in particular h-refinement, of rectangular parallelepiped meshes. Our technique is a unified approach for 1-, 2- and 3D domains, that can be extended ... More
A Fault-Tolerant Sequentially Consistent DSM With a Compositional Correctness ProofAug 08 2016We present the SC-ABD algorithm that implements sequentially consistent distributed shared memory (DSM). The algorithm tolerates that less than half of the processes are faulty (crash-stop). Compared to the multi-writer ABD algorithm, SC-ABD requires ... More
Universal Quantum Computing with Spin and ValleyMar 22 2012We investigate a two-electron double quantum dot with both spin and valley degrees of freedom as they occur in graphene, carbon nanotubes, or silicon, and regard the 16-dimensional space with one electron per dot as a four-qubit logic space. In the spin-only ... More
Scaling property of the critical hopping parameters for the Bose-Hubbard modelSep 17 2009Recently precise results for the boundary between the Mott insulator phase and the superfluid phase of the homogeneous Bose-Hubbard model have become available for arbitrary integer filling factor g and any lattice dimension d > 1. We use these data for ... More
Bose-Einstein condensates in a double well: mean-field chaos and multi-particle entanglementNov 07 2008A recent publication [Phys. Rev. Lett. 100, 140408 (2008)] shows that there is a relation between mean-field chaos and multi-particle entanglement for BECs in a periodically shaken double well. 'Schrodinger-cat' like mesoscopic superpositions in phase-space ... More
World-line formulation of chiral kinetic theory in topological background gauge fieldsDec 11 2017In heavy-ion collisions, an interesting question of phenomenological relevance is how the chiral imbalance generated at early times persists through a fluctuating background of sphalerons in addition to other "non-anomalous" interactions with the QGP. ... More
Instability in cosmological topologically massive gravity at the chiral pointMay 19 2008Oct 22 2009We consider cosmological topologically massive gravity at the chiral point with positive sign of the Einstein-Hilbert term. We demonstrate the presence of a negative energy bulk mode that grows linearly in time. Unless there are physical reasons to discard ... More
Transient supersolid properties in an array of dipolar quantum dropletsJan 23 2019We study theoretically and experimentally the emergence of supersolid properties in a dipolar Bose-Einstein condensate. The theory reveals a ground state phase diagram with three distinct regimes - a regular Bose-Einstein condensate, incoherent and coherent ... More
The chiral anomaly, Berry's phase and chiral kinetic theory, from world-lines in quantum field theoryJan 12 2017Feb 07 2017We outline a novel chiral kinetic theory framework for systematic computations of the Chiral Magnetic Effect (CME) in ultrarelativistic heavy-ion collisions. The real part of the fermion determinant in the QCD effective action is expressed as a supersymmetric ... More
Bootstrap tuning in ordered model selectionJul 17 2015In the problem of model selection for a given family of linear estimators, ordered by their variance, we offer a new "smallest accepted" approach motivated by Lepski's method and multiple testing theory. The procedure selects the smallest model which ... More
How to find simple nonlocal stability and resilience measuresJun 18 2017Stability of dynamical systems is a central topic with applications in widespread areas such as economy, biology, physics and mechanical engineering. The dynamics of nonlinear systems may completely change due to perturbations forcing the solution to ... More
Computing the Tutte Polynomial of a Matroid from its Lattice of Cyclic FlatsJul 24 2014Sep 25 2014We show how the Tutte polynomial of a matroid $M$ can be computed from its condensed configuration, which is a statistic of its lattice of cyclic flats. The results imply that the Tutte polynomial of $M$ is already determined by the abstract lattice of ... More
Eta-eta' mixing in U(3) chiral perturbation theoryJul 16 2001We investigate eta-eta' mixing in infrared regularized U(3) chiral perturbation theory by calculating the eta and eta' masses up to one-loop order. From this analysis it becomes obvious that even at leading order eta-eta' mixing does not obey the usually ... More
Transmission from reverse reaction coordinate mappingsSep 27 2018Jan 06 2019We point out that the transport properties of non-interacting fermionic chains tunnel-coupled to two reservoirs at their ends can be mapped to those of a single quantum dot that is tunnel-coupled to two transformed reservoirs. The parameters of the chain ... More
Differences between mean-field dynamics and N-particle quantum dynamics as a signature of entanglementMay 05 2008A Bose-Einstein condensate in a tilted double-well potential under the influence of time-periodic potential differences is investigated in the regime where the mean-field (Gross-Pitaevskii) dynamics become chaotic. For some parameters near stable regions, ... More
Yangian Symmetry of Long-Range gl(N) Integrable Spin ChainsNov 29 2007Feb 28 2008An interesting type of spin chain has appeared in the context of the planar AdS/CFT correspondence: It is based on an integrable nearest-neighbor spin chain, and it is perturbatively deformed by long-range interactions which apparently preserve the integrable ... More
The N=4 SYM Integrable Super Spin ChainJul 03 2003Sep 26 2003Recently it was established that the one-loop planar dilatation generator of N=4 Super Yang-Mills theory may be identified, in some restricted cases, with the Hamiltonians of various integrable quantum spin chains. In particular Minahan and Zarembo established ... More
The boundary Harnack inequality for variable exponent $p$-Laplacian, Carleson estimates, barrier functions and $p(\cdot)$-harmonic measuresMay 12 2014We investigate various boundary decay estimates for $p(\cdot)$-harmonic functions. For domains in $\mathbb{R}^n, n\geq 2$ satisfying the ball condition ($C^{1,1}$-domains) we show the boundary Harnack inequality for $p(\cdot)$-harmonic functions under ... More
Detection of motional ground state population of a trapped ion using delayed pulsesSep 30 2015Efficient preparation and detection of the motional state of trapped ions is important in many experiments ranging from quantum computation to precision spectroscopy. We investigate the stimulated Raman adiabatic passage (STIRAP) technique for the manipulation ... More
Simulation Environment for Link Energy Estimation in Networks-on-Chip with Virtual ChannelsMay 23 2019Network-on-chip (NoC) is the most promising design paradigm for the interconnect architecture of a multiprocessor system-on-chip (MPSoC). On the downside, a NoC has a significant impact on the overall energy consumption of the system. NoC simulators are ... More
World-line construction of a covariant chiral kinetic theoryFeb 04 2017We discuss a novel world-line framework for computations of the Chiral Magnetic Effect (CME) in ultrarelativistic heavy-ion collisions. Starting from the fermion determinant in the QCD effective action, we show explicitly how its real part can be expressed ... More
Asymptotic scaling behavior of self-avoiding walks on critical percolation clustersSep 11 2014We study self-avoiding walks on three-dimensional critical percolation clusters using a new exact enumeration method. It overcomes the exponential increase in computation time by exploiting the clusters' fractal nature. We enumerate walks of over $10^4$ ... More
An Interactive Tool to Explore and Improve the Ply Number of DrawingsAug 30 2017Given a straight-line drawing $\Gamma$ of a graph $G=(V,E)$, for every vertex $v$ the ply disk $D_v$ is defined as a disk centered at $v$ where the radius of the disk is half the length of the longest edge incident to $v$. The ply number of a given drawing ... More
Optimizing electrically controlled echo sequences for the exchange-only qubitOct 14 2015Recently, West and Fong [New J. Phys. 14, 083002 (2012)] introduced an echo scheme for an exchange-only qubit, which relies entirely on the exchange-interaction. Here, we compare two different exchange-based sequences and two optimization strategies, ... More
Coherently controlled entanglement generation in a binary Bose-Einstein condensateFeb 09 2007Considering a two-component Bose-Einstein condensate in a double-well potential, a method to generate a Bell state consisting of two spatially separated condensates is suggested. For repulsive interactions, the required tunnelling control is achieved ... More
On Mean Field Limits for Dynamical SystemsJul 11 2013Sep 04 2015We present a purely probabilistic proof of propagation of molecular chaos for $N$-particle systems in dimension $3$ with interaction forces scaling like $1/\vert q\vert^{\lambda}$ with $\lambda<2$ and cut-off at $q = N^{-1/3}$. The proof yields a Gronwall ... More
Equidistributed statistics on matchings and permutationsDec 09 2011We show that the bistatistic of right nestings and right crossings in matchings without left nestings is equidistributed with the number of occurrences of two certain patterns in permutations, and furthermore that this equidistribution holds when refined ... More
Asymptotic series for the splitting of separatrices near a Hamiltonian bifurcationJun 14 2008This is a proof of an asymptotic formula which describes exponentially small splitting of separatrices in a generic analytic family of area-preserving maps near a Hamiltonian saddle-centre bifurcation. As a particular case and in combination with an earlier ... More
Quantum Deformations of the One-Dimensional Hubbard ModelFeb 06 2008May 21 2008The centrally extended superalgebra psu(2|2)xR^3 was shown to play an important role for the integrable structures of the one-dimensional Hubbard model and of the planar AdS/CFT correspondence. Here we consider its quantum deformation U_q(psu(2|2)xR^3) ... More
Variational Multi-Phase Segmentation using High-Dimensional Local FeaturesFeb 26 2019We propose a novel method for multi-phase segmentation of images based on high-dimensional local feature vectors. While the method was developed for the segmentation of extremely noisy crystal images based on localized Fourier transforms, the resulting ... More
Sparse Polynomial Zonotopes: A Novel Set Representation for Reachability AnalysisJan 07 2019We introduce sparse polynomial zonotopes, a new set representation for formal verification of hybrid systems. Sparse polynomial zonotopes can represent non-convex sets and are generalizations of zonotopes and Taylor models. Operations like Minkowski sum, ... More
Miquel Dynamics, Clifford Lattices and the Dimer ModelAug 13 2018Miquel dynamics were introduced by Ramassamy as a discrete time evolution of square grid circle patterns on the torus. In each time step every second circle in the pattern is replaced with a new one by employing Miquel's six circle theorem. Inspired by ... More
Phragmén-Lindelöf theorems and p-harmonic measures for sets near low-dimensional hyperplanesMar 18 2015Dec 03 2015We prove estimates of a $p$-harmonic measure, $p \in (n-m, \infty]$, for sets in $\mathbf{R}^n$ which are close to an $m$-dimensional hyperplane $\Lambda \subset \mathbf{R}^n$, $m \in [0,n-1]$. Using these estimates, we derive results of Phragm\'en-Lindel\"of ... More
An extended model of wine fermentation including aromas and acidsJan 05 2019The art of viticulture and the quest for making wines has a long tradition and it just started recently that mathematicians entered this field with their main contribution of modelling alcoholic fermentation. These models consist of systems of ordinary ... More
Is it ethical to avoid error analysis?Jun 30 2017Machine learning algorithms tend to create more accurate models with the availability of large datasets. In some cases, highly accurate models can hide the presence of bias in the data. There are several studies published that tackle the development of ... More
The RTT-Realization for the Deformed gl(2|2) YangianJan 29 2014Mar 23 2018In this paper we work out the RTT-realization for the Yangian algebra of the Hubbard model and AdS/CFT correspondence. We find that this Yangian algebra is of a non-standard type in which the levels of the Yangian mix. The crucial feature that allows ... More
On Symmetry Enhancement in the psu(1,1|2) Sector of N=4 SYMJul 06 2007Sep 19 2007Strong evidence indicates that the spectrum of planar anomalous dimensions of N=4 super Yang-Mills theory is given asymptotically by Bethe equations. A curious observation is that the Bethe equations for the psu(1,1|2) subsector lead to very large degeneracies ... More
Higher-order corrections for the dynamic hyperfine structure of muonic atomsSep 18 2018A method for precise calculation of the energy corrections due to second order electric quadrupole interactions, as well as mixed electric quadrupole-vacuum polarization in the framework of the dynamic hyperfine structure in heavy muonic atoms is presented. ... More
Source reconstruction using a bilevel optimisation method with a smooth weighted distance functionJul 16 2016We consider a bilevel optimatisation method for inverse linear atmospheric dispersion problems where both linear and non-linear model parameters are to be determined. We propose that a smooth weighted Mahalanobis distance function is used and derive sufficient ... More
Mixed Motives and Geometric Representation Theory in Equal CharacteristicSep 19 2016Apr 12 2019Let $\mathbb{k}$ be a field of characteristic $p$. We introduce a formalism of mixed sheaves with coefficients in $\mathbb{k}$ and showcase its use in representation theory. More precisely, we construct for all quasi-projective schemes $X$ over an algebraic ... More
Asymmetric Dark Matter StarsJul 03 2015We study the possibility of asymmetric dark matter with self-interactions forming compact stable objects. We solve the Tolman-Oppenheimer-Volkoff equation and find the mass-radius relation of such "dark stars", their density profile and their Chandrasekhar ... More
Dynamics from seconds to hours in Hodgkin-Huxley model with time-dependent ion concentrations and buffer reservoirsApr 11 2014Aug 12 2014The classical Hodgkin--Huxley (HH) model neglects the time-dependence of ion concentrations in spiking dynamics. The dynamics is therefore limited to a time scale of milliseconds, which is determined by the membrane capacitance multiplied by the resistance ... More
A measure theoretic approach to linear inverse atmospheric dispersion problemsMay 28 2013Sep 17 2014Using measure theoretic arguments, we provide a general framework for describing and studying the general linear inverse dispersion problem where no a priori assumptions on the source function has been made. We investigate the source-sensor relationship ... More