Results for "Christian Unger"

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Kolmogorov $n$-widths for linear dynamical systemsJun 26 2018Kolmogorov $n$-widths and Hankel singular values are two commonly used concepts in model reduction. Here we show that for the special case of linear time-invariant dynamical (LTI) systems, these two concepts are directly connected. More specifically, ... More
Signatures of hermitian forms, positivity, and an answer to a question of Procesi and SchacherNov 19 2015Sep 27 2016Using the theory of signatures of hermitian forms over algebras with involution, developed by us in earlier work, we introduce a notion of positivity for symmetric elements and prove a noncommutative analogue of Artin's solution to Hilbert's 17th problem, ... More
An Empirical Evaluation Study on the Training of SDC Features for Dense Pixel MatchingApr 12 2019Training a deep neural network is a non-trivial task. Not only the tuning of hyperparameters, but also the gathering and selection of training data, the design of the loss function, and the construction of training schedules is important to get the most ... More
SDC - Stacked Dilated Convolution: A Unified Descriptor Network for Dense Matching TasksApr 05 2019Dense pixel matching is important for many computer vision tasks such as disparity and flow estimation. We present a robust, unified descriptor network that considers a large context region with high spatial variance. Our network has a very large receptive ... More
SceneFlowFields++: Multi-frame Matching, Visibility Prediction, and Robust Interpolation for Scene Flow EstimationFeb 26 2019State-of-the-art scene flow algorithms pursue the conflicting targets of accuracy, run time, and robustness. With the successful concept of pixel-wise matching and sparse-to-dense interpolation, we push the limits of scene flow estimation. Avoiding strong ... More
Combinatorics of Lattice QCD at Strong CouplingNov 17 2014Thermodynamics in the strong coupling limit of lattice QCD has features which may be similar to those of continuum QCD, such as a chiral critical end point and a nuclear liquid gas transition. Here I compare the combinatorics of staggered and Wilson fermions ... More
Successive failures of approachabilityFeb 16 2017Jun 11 2018Motivated by showing that in ZFC we cannot construct a special Aronszajn tree on some cardinal greater than $\aleph_1$, we produce a model in which the approachability property fails (hence there are no special Aronszajn trees) at all regular cardinals ... More
Collective rheology in quasi static shear flow of granular mediaSep 20 2010This paper is devoted to the basic question of what factors determine the strain field in a quasi static granular flow. It is shown that using stress - strain rate relations is not the proper way to understand quasi static rheology. An alternative approach ... More
Refraction of shear zones in granular materialsOct 03 2006Jan 08 2007We study strain localization in slow shear flow focusing on layered granular materials. A heretofore unknown effect is presented here. We show that shear zones are refracted at material interfaces in analogy with refraction of light beams in optics. This ... More
Highlights from the Pierre Auger Observatory (ICRC17)Oct 25 2017In this contribution we summarize the highlights from the Pierre Auger Observatory presented at the 35th International Cosmic Ray Conference. We discuss the update of the measurement of the energy spectrum of cosmic rays over a wide range of energy ($10^{17.5}$ ... More
Cosmic Rays above the KneeDec 15 2008An overview on the present observational status and phenomenological understanding of cosmic rays above 10^16 eV is given. Above these energies the cosmic ray flux is expected to be gradually dominated by an extra-galactic component. In order to investigate ... More
A Unified Framework for Multi-Sensor HDR Video ReconstructionAug 22 2013One of the most successful approaches to modern high quality HDR-video capture is to use camera setups with multiple sensors imaging the scene through a common optical system. However, such systems pose several challenges for HDR reconstruction algorithms. ... More
Discontinuity propagation in delay differential-algebraic equationsMar 12 2018The propagation of primary discontinuities in initial value problems for linear delay differential-algebraic equations (DDAEs) is discussed. Based on the (quasi-) Weierstra{\ss} form for regular matrix pencil, a complete characterization of the different ... More
Relaxed Logarithmic Barrier Function Based Model Predictive Control of Linear SystemsMar 11 2015In this paper, we investigate the use of relaxed logarithmic barrier functions in the context of linear model predictive control. We present results that allow to guarantee asymptotic stability of the corresponding closed-loop system, and discuss further ... More
Friction force: from mechanics to thermodynamicsNov 17 2009Jul 01 2010We study some mechanical problems in which a friction force is acting on the system. Using the fundamental concepts of state, time evolution and energy conservation we explain how to extend Newtonian mechanics to thermodynamics. We arrive at the two laws ... More
On the relativistic KMS condition for the P(φ)_2 modelSep 29 2006The relativistic KMS condition introduced by Bros and Buchholz provides a link between quantum statistical mechanics and quantum field theory. We show that for the $P(\phi)_2$ model at positive temperature, the two point function for fields satisfies ... More
Spectral properties and chiral symmetry violations of (staggered) domain wall fermions in the Schwinger modelFeb 26 2016Jul 05 2016We follow up on a suggestion by Adams and construct explicit domain wall fermion operators with staggered kernels. We compare different domain wall formulations, namely the standard construction as well as Borici's modified and Chiu's optimal construction, ... More
Thermal Quantum Fields with Spatially Cut-off Interactions in 1+1 Space-time DimensionsJul 25 2003We construct interacting quantum fields in 1+1 space-time dimensions, representing charged or neutral scalar bosons at positive temperature and zero chemical potential. Our work is based on prior work by Klein and Landau and Hoegh-Krohn. Generalized path ... More
Noise threshold for universality of 2-input gatesNov 02 2007Sep 06 2008Evans and Pippenger showed in 1998 that noisy gates with 2 inputs are universal for arbitrary computation (i.e. can compute any function with bounded error), if all gates fail independently with probability epsilon and epsilon<theta, where theta is roughly ... More
On spatial and temporal multilevel dynamics and scaling effects in epileptic seizuresMar 30 2011Jul 29 2011Epileptic seizures are one of the most well-known dysfunctions of the nervous system. During a seizure, a highly synchronized behavior of neural activity is observed that can cause symptoms ranging from mild sensual malfunctions to the complete loss of ... More
Duck Traps: Two-dimensional Critical Manifolds in Planar SystemsAug 30 2018Nov 05 2018In this work we consider two-dimensional critical manifolds in planar fast-slow systems near fold and so-called canard (=`duck') points. These higher-dimension, and lower-codimension, situation is directly motivated by the case of hysteresis operators ... More
Differential Characters and Geometric ChainsMar 26 2013Apr 09 2013We study Cheeger-Simons differential characters and provide geometric descriptions of the ring structure and of the fiber integration map. The uniqueness of differential cohomology (up to unique natural transformation) is proved by deriving an explicit ... More
Thermal Quantum Fields without Cut-offs in 1+1 Space-time DimensionsMar 26 2004We construct interacting quantum fields in 1+1 dimensional Minkowski space, representing neutral scalar bosons at positive temperature. Our work is based on prior work by Klein and Landau and Hoegh-Krohn
Introduction to nuclear astrophysicsNov 20 2009In the first lecture of this volume, we will present the basic fundamental ideas regarding nuclear processes occurring in stars. We start from stellar observations, will then elaborate on some important quantum-mechanical phenomena governing nuclear reactions, ... More
Isotropy of Angular Frequencies and Weak Chimeras With Broken SymmetryDec 04 2015Jul 18 2016The notion of a weak chimeras provides a tractable definition for chimera states in networks of finitely many phase oscillators. Here we generalize the definition weak chimera to a more general class of equivariant dynamical systems by characterizing ... More
Raiders of the lost spacetimeMay 21 2014Spacetime as we know and love it is lost in most approaches to quantum gravity. For many of these approaches, as inchoate and incomplete as they may be, one of the main challenges is to relate what they take to be the fundamental non-spatiotemporal structure ... More
Perturbative Quantum Field Theory in the String-Inspired FormalismJan 05 2001Jan 06 2001We review the status and present range of applications of the ``string-inspired'' approach to perturbative quantum field theory. This formalism offers the possibility of computing effective actions and S-matrix elements in a way which is similar in spirit ... More
Regular and Biregular module algebrasSep 30 2008Motivated by the study of von Neumann regular skew groups as carried out by Alfaro, Ara and del Rio in 1995 we investigate regular and biregular Hopf module algebras. If $A$ is an algebra with an action by an affine Hopf algebra $H$, then any $H$-stable ... More
Duality for partial group actionsNov 06 2007Given a finite group G acting as automorphisms on a ring A, the skew group ring A*G is an important tool for studying the structure of G-stable ideals of A. The ring A*G is G-graded, i.e.G coacts on A*G. The Cohen-Montgomery duality says that the smash ... More
The radial effective temperature distribution of steady-state, mass-losing accretion disksJun 10 1999Mass loss appears to be a common phenomenon among disk-accreting astrophysical systems. An outflow emanating from an accretion disk can act as a sink for mass, angular momentum and energy and can therefore alter the dissipation rates and effective temperatures ... More
The Evolution of Cataclysmic VariablesAug 23 2011Sep 02 2011I review our current understanding of the evolution of cataclysmic variables (CVs). I first provide a brief introductory "CV primer", in which I describe the physical structure of CVs, as well as their astrophysical significance. The main part of the ... More
Cataclysmic Variables: Eight Breakthroughs in Eight YearsJan 14 2011May 04 2011The last few years have seen tremendous progress in our understanding of cataclysmic variable stars. As a result, we are finally developing a much clearer picture of their evolution as binary systems, the physics of the accretion processes powering them, ... More
Two algebraic properties of thermal quantum field theoriesJan 05 1999May 05 2004We establish the Schlieder and the Borchers property for thermal field theories. In addition, we provide some information on the commutation and localization properties of projection operators.
The Relation Between KMS-states for Different TemperaturesMar 30 1998May 05 2004Given a thermal field theory for some temperature $\beta^{-1}$, we construct the theory at an arbitrary temperature $ 1 / \beta'$. Our work is based on a construction invented by Buchholz and Junglas, which we adapt to thermal field theories. In a first ... More
Decay of Spatial Correlations in Thermal StatesMar 27 1998We study the cluster properties of thermal equilibrium states in theories with a maximal propagation velocity (such as relativistic QFT). Our analysis, carried out in the setting of algebraic quantum field theory, shows that there is a tight relation ... More
One non-relativistic particle coupled to a photon fieldFeb 01 2002Feb 20 2003We investigate the ground state energy of an electron coupled to a photon field. First, we regard the self-energy of a free electron, which we describe by the Pauli-Fierz Hamiltonian. We show that, in the case of small values of the coupling constant ... More
Evolution variational inequality and Wasserstein control in variable curvature contextSep 07 2015Nov 08 2015In this note we continue the analysis of metric measure space with variable ricci curvature bounds. First, we study $(\kappa,N)$-convex functions on metric spaces where $\kappa$ is a lower semi-continuous function, and gradient flow curves in the sense ... More
Embedded surfaces and almost complex structuresDec 09 1998We prove necessary and sufficient conditions for a smooth surface in a 4-manifold X to be pseudoholomorphic with respect to some almost complex structure on X. This provides a systematic approach to the construction of pseudoholomorphic curves that do ... More
Effective Theory Approach to W-Pair Production near ThresholdAug 06 2007In this talk, I review the effective theory approach to unstable particle production and present results of a calculation of the process e- e+ ->mu- nubar_mu u dbar X near the W-pair production threshold up to next-to-leading order in GammaW/MW ~ alpha ... More
Top quark signatures of Higgsless modelsOct 09 2006In these proceedings I describe the use of tree level unitarity to constrain top quark signatures of Higgsless electroweak models and discuss implications for collider phenomenology.
Non-congruence of homology Veech groups in genus twoJan 28 2013Feb 13 2014We study the action of the Veech group of square-tiled surfaces of genus two on homology. This action defines the homology Veech group which is a subgroup of $\textrm{SL}_2(\mathcal{O}_D)$ where $\mathcal{O}_D$ is a quadratic order of square discriminant. ... More
A discrete log gas, discrete Toeplitz determinants with Fisher-Hartwig singularities, and Gaussian Multiplicative ChaosSep 11 2015We consider a log-gas on a discretization of the unit circle. We prove that if the gas is not too dense, or the number of particles in the gas is not too large compared to the scale of the discretization, the absolute value of the characteristic polynomial ... More
Precise model of Hawking radiation from the tunnelling mechanismNov 05 2014Aug 07 2015We recently improved the famous result of Parikh and Wilczek, who found a probability of emission of Hawking radiation which is compatible with a non-strictly thermal spectrum, showing that such a probability of emission is really associated to two non-strictly ... More
A clarification on the debate on "the original Schwarzschild solution"Oct 28 2010Mar 25 2011Now that English translations of Schwarzschild's original paper exist, that paper has become accessible to more people. Historically, the so-called "standard Schwarzschild solution" was not the original Schwarzschild's work, but it is actually due to ... More
Interferometric detection of gravitational waves arising from extended theories of gravityFeb 13 2009Even if Einstein's General Relativity achieved a great success and overcame lots of experimental tests, it also showed some shortcomings and flaws which today advise theorists to ask if it is the definitive theory of gravity. In this letter Proceeding ... More
Using long-baseline interferometric gravitational waves detectors for high precision measures of the gravitational accelerationNov 07 2006Jan 25 2007A derivation of the optical axis lenght fluctations due by tilts of the mirrors of the Fabry-Perot cavity of long-baseline interferometers for the detection of gravitational waves in presence of the gravitational field of the earth is discussed. By comparing ... More
Time-Dependent Schrodinger Equation for Black Hole Evaporation: no Information LossApr 06 2013Nov 06 2014In 1976 S. Hawking claimed that "Because part of the information about the state of the system is lost down the hole, the final situation is represented by a density matrix rather than a pure quantum state" (Verbatim from ref. 2). This was the starting ... More
Radiation dominated era and the power of general relativityMay 31 2012An analysis in the framework of the radiation dominated era permits to put bounds on the weak modification of general relativity which arises from the Lagrangian R^{1+epsilon}. Such a theory has been recently discussed in various papers in the literature. ... More
Primordial gravity's breathOct 08 2011By releasing a formula that directly connects the average amplitude of the relic stochastic gravitational-wave background (SGWB) with the Inflaton field and the equation for the characteristic amplitude h_c for the relic SGWB, in this paper the upper ... More
Interferometric detection of gravitational waves: the definitive test for General RelativityMay 15 2009Jun 08 2009Even if Einstein's General Relativity achieved a great success and overcame lots of experimental tests, it also showed some shortcomings and flaws which today advise theorists to ask if it is the definitive theory of gravity. In this essay we show that, ... More
Conformal Transformation Properties of the B-type SupercurrentOct 19 1999We investigate the superconformal transformation properties of the supercurrent as well as of the superconformal anomalies themselves in d=4, N=1 supersymmetric quantum field theory. Matter supercurrent and anomalies are coupled to a classical background ... More
Algebraic representations of von Neumann algebrasSep 08 2006Mar 09 2010An algebraic extended bilinear Hilbert semispace is proposed as being the natural representation space for the algebras of von Neumann.This bilinear Hilbert semispace has a well defined structure given by the representation space of an algebraic general ... More
Quantized gravito-electro-magnetic interactions of bilinear typeJul 26 2006The interactions inside the (bisemi)particles are envisaged from two points of view: The first approach, based on the reducible representations of algebraic bilinear semigroups, allows to describe explicitly the interactions between (bisemi)particles ... More
Dynamic Composition of Evolving Process TypesDec 25 2011Classical approaches like process algebras or labelled transition systems deal with static composition to model non-trivial concurrent or distributed systems; this is not sufficient for systems with dynamic architecture and with variable number of components. ... More
Tool-Assisted Multi-Facet Analysis of Formal Specifications (Using Alelier-B and ProB)Oct 09 2009Tool-assisted analysis of software systems and convenient guides to practise the formal methods are still motivating challenges. This article addresses these challenges. We ex periment on analysing a formal speci?cation from multiple aspects. The B method ... More
Can Component/Service-Based Systems Be Proved Correct?Oct 10 2009Component-oriented and service-oriented approaches have gained a strong enthusiasm in industries and academia with a particular interest for service-oriented approaches. A component is a software entity with given functionalities, made available by a ... More
Characterizing Slow Exit and Entrance PointsJan 29 2012Feb 02 2012Geometric Singular Perturbation Theory (GSPT) and Conley Index Theory are two powerful techniques to analyze dynamical systems. Conley already realized that using his index is easier for singular perturbation problems. In this paper, we will revisit Conley's ... More
Exploring Parameter Spaces in Dynamical SystemsJul 12 2008The parameter space of dynamical systems arising in applications is often found to be high-dimensional and difficult to explore. We construct a fast algorithm to numerically analyze "quantitative features" of dynamical systems depending on parameters. ... More
Jet-like QED processes : on general properties of impact factorsJan 17 2014In this article, general properties of impact factors involved in jet-like QED processes are explored. In particular, a general link is established between their helicity properties and their order of magnitude as defined by jet-like kinematics. Exact ... More
On the Unique Reconstruction of Induced Spherical MagnetizationsJul 20 2015Aug 03 2016Recovering spherical magnetizations $m$ from magnetic field data in the exterior is a highly non-unique problem. A spherical Hardy-Hodge decomposition supplies information on what contributions of the magnetization $m$ are recoverable but it does not ... More
A Locale for Minimal Bad SequencesAug 07 2012We present a locale that abstracts over the necessary ingredients for constructing a minimal bad sequence, as required in classical proofs of Higman's lemma and Kruskal's tree theorem.
Higher order QCD results for the fermionic contributions of the Higgs-boson decay into two photons and the decoupling function for the MSbar renormalized fine-structure constantApr 13 2014We compute the decoupling function of the MSbar renormalized fine-structure constant up to four-loop order in perturbative QCD. The results are used in order to determine the related top-quark contributions to the Higgs-boson decay into two photons in ... More
Polarized Spinoptics and Symplectic PhysicsDec 16 2013We recall the groundwork of spinoptics based on the coadjoint orbits, of given color and spin, of the group of isometries of Euclidean three-space; this model has originally been put forward by Souriau in his treatise "Structure des Syst\'emes Dynamiques", ... More
The high density equation of state: constraints from accelerators and astrophysicsNov 21 2007The nuclear equation of state (EoS) at high densities and/or extreme isospin is one of the longstanding problems of nuclear physics. In the last years substantial progress has been made to constrain the EoS both, from the astrophysical side and from accelerator ... More
Kaon production in heavy ion reactions at intermediate energiesJul 07 2005Sep 01 2005The article reviews the physics related to kaon and antikaon production in heavy ion reactions at intermediate energies. Chiral dynamics predicts substantial modifications of the kaon properties in a dense nuclear environment. The status of the theoretical ... More
Matsuki's double coset decomposition via gradient mapsDec 20 2007Sep 26 2008Let $G$ be a real-reductive Lie group and let $G_1$ and $G_2$ be two subgroups given by involutions. We show how the technique of gradient maps can be used in order to obtain a new proof of Matsuki's parametrization of the closed double cosets $G_1\backslash ... More
Market simulation with hierarchical information fluxMay 04 2002We assume the market price to diffuse in a hierarchical comb of barriers, the heights of which represent the importance of new information entering the market. We find fat tails with the desired exponent for the price change distribution, and effective ... More
Sznajd opinion dynamics with global and local neighbourhoodFeb 15 2004In this modification of the Sznajd consensus model on the square lattice, two people of arbitrary distance who agree in their opinions convince their nearest neighbours of this opinion. Similarly to the mean field theory of Slanina and Lavicka, the times ... More
Corrections to Moments of the Photon Spectrum in the Inclusive Decay B \to X_s γOct 29 1997Jun 25 1999We investigate the two main uncertainties on the extraction of the nonperturbative matrix elements $\bar{\Lambda}$ and $\lambda_1$ from moments of the inclusive rare FCNC decay $B \to X_s \gamma$. The first one is due to unknown matrix elements of higher ... More
Dining Cryptographers with 0.924 Verifiable Collision ResolutionFeb 07 2014Jan 03 2015The dining cryptographers protocol implements a multiple access channel in which senders and recipients are anonymous. A problem is that a malicious participant can disrupt communication by deliberately creating collisions. We propose a computationally ... More
Comments on the arterial spin labelling quantification recommended by the ISMRM perfusion study group and the European consortium for ASL in dementiaMar 11 2017Jun 02 2017A petition for more careful considerations towards the usage of a quantification approach for ASL which has been recommended by the ISMRM perfusion study group and the European consortium for ASL in dementia.
The Fluctuation Theorem as a Gibbs PropertyDec 18 1998Common ground to recent studies exploiting relations between dynamical systems and non-equilibrium statistical mechanics is, so we argue, the standard Gibbs formalism applied on the level of space-time histories. The assumptions (chaoticity principle) ... More
Characterising subspaces of Banach spaces with a Schauder basis having the shift propertyJun 02 2011We give an intrinsic characterisation of the separable reflexive Banach spaces that embed into separable reflexive spaces with an unconditional basis all of whose normalised block sequences with the same growth rate are equivalent. This uses methods of ... More
Microscopic collectivity: The ridge and strangeness enhancement from string-string interactionsJul 13 2018Jul 26 2018We present the microscopic model for collective effects, built on string-string interactions (string shoving and rope hadronization), recently implemented in the PYTHIA 8 and DIPSY event generators. Rope hadronization is shown to give a good description ... More
Factorization of two-particle distributions in AMPT simulations of Pb-Pb collisions at $\mathbf{\sqrt{s_{\text{NN}}}} $ = 5.02 TeVJul 13 2018The flow ansatz states that the single-particle distribution of a given event can be described in terms of the complex flow coefficients $V_n$. Multi-particle distributions can therefore be expressed as products of these single-particle coefficients; ... More
Some Comments on Entanglement and Local Thermofield TheoryMay 05 2004We combine recent results of Clifton and Halvorson [1] with structural results of the author [2--5] concerning the local observables in thermofield theory. An number of interesting consequences are discussed.
Zero Sets of Solutions to Semilinear Elliptic Systems of First OrderMay 13 1998Consider a nontrivial solution to a semilinear elliptic system of first order with smooth coefficients defined over an $n$-dimensional manifold. Assume the operator has the strong unique continuation property. We show that the zero set of the solution ... More
Equivariant local cyclic homology and the equivariant Chern-Connes characterAug 24 2006We define and study equivariant analytic and local cyclic homology for smooth actions of totally disconnected groups on bornological algebras. Our approach contains equivariant entire cyclic cohomology in the sense of Klimek, Kondracki and Lesniewski ... More
Quantum SU(2) and the Baum-Connes conjectureDec 11 2012We review the formulation and proof of the Baum-Connes conjecture for the dual of the quantum group $ SU_q(2) $ of Woronowicz. As an illustration of this result we determine the $ K $-groups of quantum automorphism groups of simple matrix algebras.
A Laplace Transform Method for Molecular Mass Distribution Calculation from Rheometric DataFeb 19 2018Polydisperse linear polymer melts can be microscopically described by the tube model and fractal reptation dynamics, while on the macroscopic side the generalized Maxwell model is capable of correctly displaying most of the rheological behavior. In this ... More
Residues and filtered D-modulesMay 04 2010For an embedding of sufficiently high degree of a smooth projective variety X into projective space, we use residues to define a filtered holonomic D-module (M, F) on the dual projective space. This gives a concrete description of the intermediate extension ... More
A geometric approach to the diophantine Frobenius problemJul 12 2010It turns out that all instances of the diophantine Frobenius problem for three coprime a_i have a common geometric structure which is independent of arithmetic coincidences among the a_i. By exploiting this structure we easily obtain Johnson's formula ... More
Equivariant periodic cyclic homologyDec 01 2004We define and study equivariant periodic cyclic homology for locally compact groups. This can be viewed as a noncommutative generalization of equivariant de Rham cohomology. Although the construction resembles the Cuntz-Quillen approach to ordinary cyclic ... More
A new description of equivariant cohomology for totally disconnected groupsDec 07 2004We consider smooth actions of totally disconnected groups on simplicial complexes and compare different equivariant cohomology groups associated to such actions. Our main result is that the bivariant equivariant cohomology theory introduced by Baum and ... More
Equivariant cyclic homology for quantum groupsJan 30 2006We define equivariant periodic cyclic homology for bornological quantum groups. Generalizing corresponding results from the group case, we show that the theory is homotopy invariant, stable and satisfies excision in both variables. Along the way we prove ... More
Baryon number and charge fluctuations from lattice QCDDec 18 2012We calculate electric and baryonic charge fluctuations on the lattice. Results have been obtained with the highly improved staggered quark action (HISQ) and almost physical quark masses on lattices with spacial extent of $N_\tau=6,8,12$. Higher order ... More
Net-baryon number fluctuations in (2+1)-flavor QCDJul 29 2010We present a lattice study of net-baryon number fluctuations in (2+1)-flavor QCD. The results are based on a Taylor expansion of the pressure with respect to the baryon chemical potential. We calculate higher moments of the net-baryon number fluctuations ... More
The QCD equation of state from improved staggered fermionsJun 22 2009We calculate the equation of state in 2+1 flavor QCD at finite temperature with physical strange quark mass and almost physical light quark masses using lattices with temporal extent $N_{\tau}=8$. Calculations have been performed with two different improved ... More
On the Origins of Quantum CorrelationsDec 28 2011Feb 14 2012It is well known that quantum correlations are not only more disciplined (and hence stronger) compared to classical correlations, but they are more disciplined in a mathematically very precise sense. This raises an important physical question: What is ... More
Exactly Soluble Sector of Quantum GravityJan 09 1997Nov 07 2005Cartan's spacetime reformulation of the Newtonian theory of gravity is a generally-covariant Galilean-relativistic limit-form of Einstein's theory of gravity known as the Newton-Cartan theory. According to this theory, space is flat, time is absolute ... More
Macroscopic Observability of Fermionic Sign Changes: A Reply to GillJan 12 2015Nov 17 2016In a recent preprint [arXiv:1412.2677] Richard Gill has criticized an experimental proposal published in a journal of theoretical physics which describes how to detect a macroscopic signature of fermionic sign changes. Here I point out that Gill's worries ... More
What Really Sets the Upper Bound on Quantum Correlations?Jan 10 2011The discipline of parallelization in the manifold of all possible measurement results is shown to be responsible for the existence of all quantum correlations, with the upper bound on their strength stemming from the maximum of possible torsion within ... More
Absolute Being vs Relative BecomingOct 10 2006Apr 23 2007Contrary to our immediate and vivid sensation of past, present, and future as continually shifting non-relational modalities, time remains as tenseless and relational as space in all of the established theories of fundamental physics. Here an empirically ... More
On highly regular strongly regular graphsApr 30 2014Sep 18 2018In this paper we unify several existing regularity conditions for graphs, including strong regularity, $k$-isoregularity, and the $t$-vertex condition. We develop an algebraic composition/decomposition theory of regularity conditions. Using our theoretical ... More
Some Estimates for Planar Random Walk and Brownian MotionNov 06 2006The purpose of this note is to collect in one place a few results about simple random walk and Brownian motion which are often useful. These include standard results such as Beurling estimates, large deviation estimates, and a method for coupling the ... More
Stochastic derivatives and generalized h-transforms of Markov processesFeb 15 2011Let $R$ be a continuous-time Markov process on the time interval $[0,1]$ with values in some state space $X$. We transform this reference process $R$ into $P:=f(X_0)\exp (-\int_0^1 V_t(X_t) dt) g(X_1)\,R$ where $f,g$ are nonnegative measurable functions ... More
Girsanov theory under a finite entropy conditionJan 20 2011Jan 31 2011This paper is about Girsanov's theory. It (almost) doesn't contain new results but it is based on a simplified new approach which takes advantage of the (weak) extra requirement that some relative entropy is finite. Under this assumption, we present and ... More
Constraints on Multipartite Quantum EntropiesOct 30 2018The von Neumann entropy plays a vital role in quantum information theory. The von Neumann entropy determines, e.g., the capacities of quantum channels. Also, entropies of composite quantum systems are important for future quantum networks, and their characterization ... More
Fast SGL Fourier transforms for scattered dataSep 27 2018Spherical Gauss-Laguerre (SGL) basis functions, i. e., normalized functions of the type $L_{n-l-1}^{(l + 1/2)}(r^2) r^l Y_{lm}(\vartheta,\varphi)$, $|m| \leq l < n \in \mathbb{N}$, $L_{n-l-1}^{(l + 1/2)}$ being a generalized Laguerre polynomial, $Y_{lm}$ ... More
$\mathrm{K}$-theory and homotopies of twists on ample groupoidsJan 27 2019This paper investigates the $\mathrm{K}$-theory of twisted groupoid $\mathrm{C}^*$-algebras. It is shown that a homotopy of twists on an ample groupoid satisfying the Baum-Connes conjecture with coefficients gives rise to an isomorphism between the $\mathrm{K}$-theory ... More