Results for "Christian Burkert"

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High-Precision Dark Halo Virial Masses from Globular Cluster Numbers: Implications for Globular Cluster Formation and Galaxy AssemblyJan 03 2019We confirm that the number of globular clusters (GC) N$_{GC}$ is an excellent tracer of their host's dark halo virial mass M$_{vir}$. The simple linear relation M$_{vir} = 5 \times 10^9$ M$_{\odot} \times$ N$_{GC}$ fits the data perfectly from M$_{vir} ... More
Tracking Users across the Web via TLS Session ResumptionOct 16 2018User tracking on the Internet can come in various forms, e.g., via cookies or by fingerprinting web browsers. A technique that got less attention so far is user tracking based on TLS and specifically based on the TLS session resumption mechanism. To the ... More
The Effect of Gas Loss on the Formation of Bound Stellar ClustersJul 27 2000The effect of gas ejection on the structure and binding energy of newly formed stellar clusters is investigated. The star formation efficiency (SFE), necessary for forming a gravitationally bound stellar cluster, is determined. Two sets of numerical N-body ... More
Simulations of Direct Collisions of Gas Clouds with the Central Black HoleAug 07 2009Oct 27 2010We perform numerical simulations of clouds in the Galactic Centre (GC) engulfing the nuclear super-massive black hole and show that this mechanism leads to the formation of gaseous accretion discs with properties that are similar to the expected gaseous ... More
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
Gravitational Focusing and the Star Cluster Initial Mass FunctionJan 30 2017We discuss the possibility that gravitational focusing, is responsible for the power-law mass function of star clusters $N(\log M) \propto M^{-1}$. This power law can be produced asymptotically when the mass accretion rate of an object depends upon the ... More
Morphology of prestellar cores in pressure confined filamentsAug 03 2018Observations of prestellar cores in star-forming filaments show two distinct morphologies. While molecular line measurements often show broad cores, submillimeter continuum observations predominantly display pinched cores compared to the bulk of the filament ... More
Physics of the Galactic Center Cloud G2, on its Way towards the Super-Massive Black HoleJan 06 2012The origin, structure and evolution of the small gas cloud, G2, is investigated, that is on an orbit almost straight into the Galactic central supermassive black hole (SMBH). G2 is a sensitive probe of the hot accretion zone of Sgr A*, requiring gas temperatures ... More
Do dwarf spheroidal galaxies contain dark matter?Oct 24 1996The amount of dark matter in the four galactic dwarf spheroidals with large mass-to-light ratios is investigated. Sextans has a cut-off radius which is equal to the expected tidal radius, assuming a high mass-to-light ratio. This satellite very likely ... More
The Challenge of Modelling Galactic DisksDec 10 2008Dec 12 2008Detailed models of galactic disk formation and evolution require knowledge about the initial conditions under which disk galaxies form, the boundary conditions that affect their secular evolution and the micro-physical processes that drive the multi-phase ... More
Star Formation in Turbulent Molecular CloudsMay 17 2001Recent progress in the understanding of star formation is summarized. A consistent picture is emerging where molecular clouds form with turbulent velocity fields and clumpy substructure, imprinted already during their formation. The clouds are initially ... More
The structure of dark matter halos. Observation versus theoryMar 10 1997The rotation curves of dark matter dominated dwarf galaxies are analysed. The observations show that dark matter halos represent a one-parameter family with self similar density profiles. The global halo parameters, like total mass and scale length are ... More
Balance among gravitational instability, star formation, and accretion determines the structure and evolution of disk galaxiesMay 13 2013May 15 2013Over the past 10 Gyr, star-forming galaxies have changed dramatically, from clumpy and gas rich, to rather quiescent stellar-dominated disks with specific star formation rates lower by factors of a few tens. We present a general theoretical model for ... More
Self-Interacting Cold Dark Matter HalosDec 08 2000The evolution of halos consisting of weakly self-interacting dark matter particles is summarized. The halos initially contain a central density cusp as predicted by cosmological models. Weak self-interaction leads to the formation of an isothermal, low-density ... More
The structure and evolution of weakly self-interacting cold dark matter halosFeb 22 2000Apr 18 2000The evolution of halos consisting of weakly self-interacting dark matter particles is investigated using a new numerical Monte-Carlo N-body method. The halos initially contain kinematically cold, dense 1/r-power-law cores. For interaction cross sections ... More
Galactic Disk Formation and the Angular Momentum ProblemAug 10 2009Galactic disk formation requires knowledge about the initial conditions under which disk galaxies form, the boundary conditions that affect their secular evolution and the micro-physical processes that drive the multi-phase interstellar medium and regulate ... More
Stellar Feedback Processes: Their Impact on Star Formation and Galactic EvolutionApr 01 2004The conditions that lead to self-regulated star formation, star bursts and the formation of massive stellar clusters are discussed. Massive stars have a strong impact on their environment, especially on the evolution of dwarf galaxies which are the building ... More
The Formation of the Milky Way in the Cosmological ContextMay 17 2001The formation of the Milky Way is discussed within the context of the cold dark matter scenario. Several problems arise which can be solved if the Galaxy experienced an early phase of gas heating and decoupling from the dark matter substructure. This ... More
2-Dimensional Kinematics of Simulated Disc Merger RemnantsJun 07 2006Jan 19 2007We present a two-dimensional kinematic analysis for a sample of simulated binary disc merger remnants with mass ratios 1:1 and 3:1. For the progenitor discs we used pure stellar models as well as models with 10% of their mass in gas. A multitude of phenomena ... More
The geometry and origin of ultra-diffuse ghost galaxiesAug 31 2016Sep 02 2016The geometry and intrinsic ellipticity distribution of ultra diffuse galaxies (UDGs) is determined from the line-of-sight distribution of axial ratios q of a large sample of UDGs, detected by Koda et al. (2015) in the Coma cluster. With high significance ... More
The Structure of Dark Matter Haloes in Dwarf GalaxiesApr 12 1995Recent observations indicate that dark matter haloes have flat central density profiles. Cosmological simulations with non-baryonic dark matter predict however self similar haloes with central density cusps. This contradiction has lead to the conclusion ... More
On the Formation of Elliptical GalaxiesMar 07 1994It is shown that the violent relaxation of dissipationless stellar systems leads to universal de Vaucouleurs profiles only outside 1.5 effective radii $R_e$. Inside $1.5 R_e$ the surface density profiles depend strongly on the initial conditions and are ... More
The Cosmological Angular Momentum Problem of Low-Mass Disk GalaxiesJul 05 2000The rotational properties of the visible and dark components of low-mass disk galaxies (vrot<=100 km/s) are investigated using the Swaters sample. The rotational parameter lambda'=lambda_DM*(j_d/m_d) is determined, where lambda_DM is the dark halo spin ... More
The Structure and Dark Halo Core Properties of Dwarf Spheroidal GalaxiesJan 26 2015Jun 22 2015The structure and dark matter halo core properties of dwarf spheroidal galaxies (dSphs) are investigated. A double-isothermal model of an isothermal stellar system, embedded in an isothermal dark halo core provides an excellent fit to the various observed ... More
The Turbulent Interstellar MediumMay 03 2006An overview is presented of the main properties of the interstellar medium. Evidence is summarized that the interstellar medium is highly turbulent, driven on different length scales by various energetic processes. Large-scale turbulence determines the ... 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
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
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
A stabilizing iteration scheme for model predictive control based on relaxed barrier functionsMar 15 2016Apr 06 2016We propose and analyze a stabilizing iteration scheme for the algorithmic implementation of model predictive control for linear discrete-time systems. Polytopic input and state constraints are considered and handled by means of so-called relaxed logarithmic ... More
Staggered domain wall fermionsSep 16 2016We construct domain wall fermions with a staggered kernel and investigate their spectral and chiral properties numerically in the Schwinger model. In some relevant cases we see an improvement of chirality by more than an order of magnitude as compared ... 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
Distances and large deviations in the spatial preferential attachment modelSep 26 2018Sep 27 2018We investigate two asymptotic properties of a spatial preferential-attachment model introduced by E. Jacob and P. M\"orters (2013). First, in a regime of strong linear reinforcement, we show that typical distances are at most of doubly-logarithmic order. ... 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
On the Vacuum Polarization Density Caused by an External FieldJul 01 2003Feb 11 2004We consider an external potential, $-\lambda \phi$, due to one or more nuclei. Following the Dirac picture such a potential polarizes the vacuum. The polarization density as derived in physics literature, after a well known renormalization procedure, ... More
Quantum field theory meets Hopf algebraNov 14 2006Sep 11 2010This paper provides a primer in quantum field theory (QFT) based on Hopf algebra and describes new Hopf algebraic constructions inspired by QFT concepts. The following QFT concepts are introduced: chronological products, S-matrix, Feynman diagrams, connected ... More
A differential identity for Green functionsFeb 15 2006If P is a differential operator with constant coefficients, an identity is derived to calculate the action of exp(P) on the product of two functions. In many-body theory, P describes the interaction Hamiltonian and the identity yields a hierarchy of Green ... More
Quantum groups and interacting quantum fieldsAug 19 2002If C is a cocommutative coalgebra, a bialgebra structure can be given to the symmetric algebra S(C). The symmetric product is twisted by a Laplace pairing and the twisted product of any number of elements of S(C) is calculated explicitly. This is used ... More
Continuous-Variable Quantum Key Distribution with Entanglement in the MiddleMay 07 2012We analyze the performance of continuous-variable quantum key distribution protocols where the entangled source originates not from one of the trusted parties, Alice or Bob, but from the malicious eavesdropper in the middle. This is in contrast to the ... More
Tight Running Time Lower Bounds for Vertex Deletion ProblemsNov 17 2015May 17 2016For a graph class $\Pi$, the $\Pi$-Vertex Deletion problem has as input an undirected graph $G=(V,E)$ and an integer $k$ and asks whether there is a set of at most $k$ vertices that can be deleted from $G$ such that the resulting graph is a member of ... More
A quantum-information-theoretic complement to a general-relativistic implementation of a beyond-Turing computerMay 21 2014Jun 11 2014There exists a growing literature on the so-called physical Church-Turing thesis in a relativistic spacetime setting. The physical Church-Turing thesis is the conjecture that no computing device that is physically realizable (even in principle) can exceed ... More
Vacuum Polarisation Tensors in Constant Electromagnetic Fields: Part IJan 27 2000Dec 29 2000The string-inspired technique is used for the calculation of vacuum polarisation tensors in constant electromagnetic fields. In the first part of this series, we give a detailed exposition of the method for the case of the QED one-loop N-photon amplitude ... More
Blue Stragglers in Globular Clusters: Observations, Statistics and PhysicsJun 13 2014This chapter explores how we might use the observed {\em statistics} of blue stragglers in globular clusters to shed light on their formation. This means we will touch on topics also discussed elsewhere in this book, such as the discovery and implications ... More
Dualité onde-corpuscule formée par une masselotte oscillante dans un milieu élastique : étude théorique et similitudes quantiquesSep 29 2016We introduce a dual wave-particle macroscopic system, where a bead oscillator oscillates in an elastic media which obeys the Klein-Gordon equation. This theoretical system comes mainly from bouncing drops experiments and also a sliding bead on a vibrating ... More
Nuclearity and split for thermal quantum field theoriesNov 26 1998Jan 05 2000We review the heuristic arguments suggesting that any thermal quantum field theory, which can be interpreted as a quantum statistical mechanics of (interacting) relativistic particles, obeys certain restrictions on its number of local degrees of freedom. ... More
On the geometry of metric measure spaces with variable curvature boundsJun 10 2015Sep 09 2015Motivated by a classical comparison result of J. C. F. Sturm we introduce a curvature-dimension condition CD(k,N) for general metric measure spaces and variable lower curvature bound k. In the case of non-zero constant lower curvature our approach coincides ... More
Auxiliary matrices for the six-vertex model at roots of 1 and a geometric interpretation of its symmetriesFeb 03 2003Apr 24 2003The construction of auxiliary matrices for the six-vertex model at a root of unity is investigated from a quantum group theoretic point of view. Employing the concept of intertwiners associated with the quantum loop algebra $U_q(\tilde{sl}_2)$ at $q^N=1$ ... More
Colours associated to non simply-laced Lie algebras and exact S-matricesOct 31 2000Jan 02 2001A new set of exact scattering matrices in 1+1 dimensions is proposed by solving the bootstrap equations. Extending earlier constructions of colour valued scattering matrices this new set has its colour structure associated to non simply-laced Lie algebras. ... More
PT Symmetry of the non-Hermitian XX Spin-Chain: Non-local Bulk Interaction from Complex Boundary FieldsMar 31 2008The XX spin-chain with non-Hermitian diagonal boundary conditions is shown to be quasi-Hermitian for special values of the boundary parameters. This is proved by explicit construction of a new inner product employing a "quasi-fermion" algebra in momentum ... More
Turning the Quantum Group Invariant XXZ Spin-Chain Hermitian: A Conjecture on the Invariant ProductSep 24 2007This is a continuation of a previous joint work with Robert Weston on the quantum group invariant XXZ spin-chain (math-ph/0703085). The previous results on quasi-Hermiticity of this integrable model are briefly reviewed and then connected with a new construction ... More
Solving Baxter's TQ-equation via representation theoryNov 09 2004Nov 23 2004Baxter's TQ-equation is solved for the six-vertex model using the representation theory of quantum groups at roots of unity. A novel simplified construction of the Q-operator is given depending on a new free parameter. Specializing this general construction ... More
On the logarithm of the characteristic polynomial of the Ginibre ensembleJul 30 2015We prove a slightly sharper version of a result of Rider and Vir\'ag who proved that after centering, the logarithm of the absolute value of the characteristic polynomial of the Ginibre ensemble converges in law to the Gaussian Free Field on the unit ... More
Scattering theory for Klein-Gordon equations with non-positive energyJan 11 2011Sep 09 2011We study the scattering theory for charged Klein-Gordon equations: \[\{{array}{l} (\p_{t}- \i v(x))^{2}\phi(t,x) \epsilon^{2}(x, D_{x})\phi(t,x)=0,[2mm] \phi(0, x)= f_{0}, [2mm] \i^{-1} \p_{t}\phi(0, x)= f_{1}, {array}. \] where: \[\epsilon^{2}(x, D_{x})= ... More
Spectral and scattering theory of charged $P(\varphi)_2$ modelsJun 30 2009We consider in this paper space-cutoff charged $P(\varphi)_{2}$ models arising from the quantization of the non-linear charged Klein-Gordon equation: \[ (\p_{t}+\i V(x))^{2}\phi(t, x)+ (-\Delta_{x}+ m^{2})\phi(t,x)+ g(x)\p_{\overline{z}}P(\phi(t,x), \overline{\phi}(t,x))=0, ... More
k-Means Clustering Is Matrix FactorizationDec 23 2015We show that the objective function of conventional k-means clustering can be expressed as the Frobenius norm of the difference of a data matrix and a low rank approximation of that data matrix. In short, we show that k-means clustering is a matrix factorization ... More
Galilean IsometriesMar 09 2009We introduce three nested Lie algebras of infinitesimal `isometries' of a Galilei space-time structure which play the r\^ole of the algebra of Killing vector fields of a relativistic Lorentz space-time. Non trivial extensions of these Lie algebras arise ... More
The remote_build ToolMay 15 2018This is an introduction to the remote_build tool for transparent remote session builds. The intended workflow for a user is to locally issue a build command for some session heap images and then continue working, while the actual build runs on a remote ... More
Moments and Classification for Conjugation-Invariant Rotations and Fake Uniformity in the Stochastic Radon TransformMar 06 2012We consider a generalisation of the stochastic Radon transform, introduced for an inverse problem in tomography by Panaretos. Specifically, we allow the distribution of the three-dimensional rotation in the statistical model of that work to be different ... More
On the arithmetic and geometric means of the prime numbersSep 26 2016In this paper we establish explicit upper and lower bounds for the ratio of the arithmetic and geometric means of the prime numbers, which improve the current best estimates. Further, we prove several conjectures related to this ration stated by Hassani. ... More
The Generalized Subterm Criterion in TTT2Sep 12 2016We present an SMT encoding of a generalized version of the subterm criterion and evaluate its implementation in TTT2.
Information on the inflaton field from the spectrum of relic gravitational wavesSep 23 2009Nov 18 2009After a review of a traditional analysis, it is shown a variation of a more recent treatment on the spectrum of relic gravitational waves (GWs). Then, a connection between the two different treatments will be analysed. Such a connection permits to obtain ... More
Estimates for $π(x)$ for large values of $x$ and Ramanujan's prime counting inequalityMar 07 2017Mar 29 2017In this paper we use refined approximations for Chebyshev's $\vartheta$-function to establish new explicit estimates for the prime counting function $\pi(x)$, which improve the current best estimates for large values of $x$. As an application we find ... More
Golomb's conjecture on prime gapsApr 23 2016Question 10208b (1992) of the American Mathematical Monthly asked: does there exist an increasing sequence $\{a_k\}$ of positive integers and a constant $B > 0$ having the property that $\{ a_k + n\}$ contains no more than $B$ primes for every integer ... More
Relative differential cohomologyOct 10 2013We study two notions of relative differential cohomology, using the model of differential characters. The two notions arise from the two options to construct relative homology, either by cycles of a quotient complex or of a mapping cone complex. We discuss ... More
A Harris-Kesten theorem for confetti percolationApr 26 2012Dec 27 2013Percolation properties of the dead leaves model, also known as confetti percolation, are considered. More precisely, we prove that the critical probability for confetti percolation with square-shaped leaves is 1/2. This result is related to a question ... More
Beta Beams Implementation at CERNSep 09 2011Beta Beam,the concept of generating a pure and intense (anti) neutrino beam by letting accelerated radioactive ions beta decay in a storage ring, called Decay Ring (DR), is the base of one of the proposed next generation neutrino oscillation facilities, ... More
Geometrically formal 4-manifolds with nonnegative sectional curvatureDec 06 2012Jan 31 2015A Riemannian manifold is called geometrically formal if the wedge product of any two harmonic forms is again harmonic. We classify geometrically formal compact 4-manifolds with nonnegative sectional curvature. If the sectional curvature is strictly positive, ... More
Immersions of surfaces in almost complex 4-manifoldsAug 31 2000In this note, we investigate the relation between double points and complex points of immersed surfaces in almost-complex 4-manifolds and show how estimates for the minimal genus of embedded surfaces lead to inequalities between the number of double points ... More
On nodal sets for Dirac and Laplace operatorsJul 10 1997We prove that the nodal set (zero set) of a solution of a generalized Dirac equation on a Riemannian manifold has codimension 2 at least. If the underlying manifold is a surface, then the nodal set is discrete. We obtain a quick proof of the fact that ... More
Random matrices and Riemann hypothesisSep 22 2011The curious connection between the spacings of the eigenvalues of random matrices and the corresponding spacings of the non trivial zeros of the Riemann zeta function is analyzed on the basis of the geometric dynamical global program of Langlands whose ... More
Modules Whose Small Submodules Have Krull DimensionJul 21 1998The main aim of this paper is to show that an AB5*-module whose small submodules have Krull dimension has a radical having Krull dimension. The proof uses the notion of dual Goldie dimension.
Quantum SL(3,C)'s: the missing caseOct 16 2002We study the only missing case in the classification of quantum SL(3,C)'s undertaken in our paper [J. of Algebra 213 (1999), 721--756; see http://arxiv.org/abs/q-alg/9711005], thereby completing this classification.
Local duality and mixed Hodge modulesApr 22 2009We establish a relationship between the graded quotients of a filtered holonomic D-module, their sheaf-theoretic duals, and the characteristic variety, in case the filtered D-module underlies a polarized Hodge module on a smooth algebraic variety. The ... More
New bounds for the prime counting function π(x)Sep 05 2014Jan 12 2016In this paper we establish a number of new estimates concerning the prime counting function \pi(x), which improve the estimates proved in the literature. As an application, we deduce a new result concerning the existence of prime numbers in small intervals. ... More
Units of ring spectra and their traces in algebraic K-theoryMay 05 2004Let GL_1(R) be the units of a commutative ring spectrum R. In this paper we identify the composition BGL_1(R)->K(R)->THH(R)->\Omega^{\infty}(R), where K(R) is the algebraic K-theory and THH(R) the topological Hochschild homology of R. As a corollary we ... More
Conserved charge fluctuations with HISQ fermionsJan 28 2013We calculate cumulants of fluctuations of net-baryon number, net-electric charge and net-strangeness, in the framework of lattice regularized QCD. We use a highly improved staggered quark (HISQ) action on lattices with temporal extent of N_tau=6,8 and ... More
QCD bulk thermodynamics and conserved charge fluctuations with HISQ fermionsDec 18 2012After briefly reviewing recent progress by the HotQCD collaboration in studying the 2+1 flavor QCD equation of state, we will focus on results on fluctuations of conserved charges by the BNL-Bielefeld and HotQCD collaborations. Higher order cumulants ... More
Strangeness at high temperaturesOct 11 2013We use up to fourth order cumulants of net strangeness fluctuations and their correlations with net baryon number fluctuations to extract information on the strange meson and baryon contribution to the low temperature hadron resonance gas, the dissolution ... More
Varieties of *-regular ringsApr 09 2019Given a subdirectly irreducible *-regular ring R, we show that R is a homomorphic image of a regular *-subring of an ultraproduct of the (simple) eRe, e in the minimal ideal of R; moreover, R (with unit) is directly finite if all eRe are unit-regular. ... More
A counterexample for a problem on quasi Baer modulesMay 08 2016Mar 13 2017In this note we answer two questions on quasi-Baer modules raised by Lee and Rizvi in J.Algebra (2016).
Factorial growth rates for the number of hyperbolic 3-manifolds of a given volumeSep 05 2012Nov 05 2013The work of J{\o}rgensen and Thurston shows that there is a finite number N(v) of orientable hyperbolic 3-manifolds with any given volume v. In this paper, we construct examples showing that the number of hyperbolic knot complements with a given volume ... More
On powers of Stieltjes moment sequences, IIDec 17 2004We consider the set of Stieltjes moment sequences, for which every positive power is again a Stieltjes moment sequence, we and prove an integral representation of the logarithm of the moment sequence in analogy to the L\'evy-Khinchin representation. We ... More
Normal crossing singularities and Hodge theory over Artin ringsApr 30 2012We develop a Hodge theory for relative simple normal crossing varieties over an Artinian base scheme. We introduce the notion of a mixed Hodge structure over an Artin ring, which axiomatizes the structure that is found on the cohomology of such a variety. ... More
Quantum correlations are weaved by the spinors of the Euclidean primitivesMay 30 2018The exceptional Lie group E8 plays a prominent role in both mathematics and theoretical physics. It is the largest symmetry group associated with the most general possible normed division algebra, namely, that of the non-associative real octonions, which ... More
On a Surprising Oversight by John S. Bell in the Proof of his Famous TheoremApr 03 2017Nov 11 2018Bell inequalities are usually derived by assuming locality and realism, and therefore experimental violations of Bell inequalities are usually taken to imply violations of either locality or realism, or both. But, after reviewing an oversight by Bell, ... More
Refutation of Richard Gill's Argument Against my Disproof of Bell's TheoremMar 12 2012Mar 06 2017I identify a number of errors in Richard Gill's purported refutation (arXiv:1203.1504) of my disproof of Bell's theorem. In particular, I point out that his central argument is based, not only on a rather trivial misreading of my counterexample to Bell's ... More
Restoring Local Causality and Objective Reality to the Entangled PhotonsJun 03 2011May 02 2012Unlike our basic theories of space and time, quantum mechanics is not a locally causal theory. Moreover, it is widely believed that any hopes of restoring local causality within a realistic theory have been undermined by Bell's theorem and its supporting ... More
Disproofs of Bell, GHZ, and Hardy Type Theorems and the Illusion of EntanglementApr 28 2009Oct 24 2010An elementary topological error in Bell's representation of the EPR elements of reality is identified. Once recognized, it leads to a topologically correct local-realistic framework that provides exact, deterministic, and local underpinning of at least ... More
Disproof of Bell's Theorem: Reply to CriticsMar 26 2007Jan 03 2008This is a collection of my responses to the criticisms of my argument against the impossibility proof of John Bell, which aims to undermine any conceivable local realistic completion of quantum mechanics. I plan to periodically update this preprint instead ... More
Testing Gravity-Driven Collapse of the Wavefunction via Cosmogenic NeutrinosMar 01 2005Oct 12 2005It is pointed out that the Diosi-Penrose ansatz for gravity-induced quantum state reduction can be tested by observing oscillations in the flavor ratios of neutrinos originated at cosmological distances. Since such a test would be almost free of environmental ... More
Why the Quantum Must Yield to GravityOct 26 1998Mar 08 1999After providing an extensive overview of the conceptual elements -- such as Einstein's `hole argument' -- that underpin Penrose's proposal for gravitationally induced quantum state reduction, the proposal is constructively criticised. Penrose has suggested ... More
Disproof of Bell's TheoremMar 09 2011Oct 15 2015We illustrate an explicit counterexample to Bell's theorem by constructing a pair of spin variables in S^3 that exactly reproduces the EPR-Bohm correlation in a manifestly local-realistic manner.
Disproof of Bell's Theorem by Clifford Algebra Valued Local VariablesMar 20 2007Apr 22 2010It is shown that Bell's theorem fails for the Clifford algebra valued local realistic variables. This is made evident by exactly reproducing quantum mechanical expectation value for the EPR-Bohm type spin correlations observable by means of a local, deterministic, ... More
emgr - The Empirical Gramian FrameworkNov 02 2016May 28 2018System Gramian matrices are a well-known encoding for properties of input-output systems such as controllability, observability or minimality. These so-called system Gramians were developed in linear system theory for applications such as model order ... More
Uniruled Surfaces of General TypeAug 24 2006Nov 06 2006We give a systematic construction of uniruled surfaces in positive characteristic. Using this construction, we find surfaces of general type with non-trivial vector fields, surfaces with arbitrarily non-reduced Picard schemes as well as surfaces with ... More
Non-classical Godeaux SurfacesApr 21 2008Aug 25 2008A non-classical Godeaux surface is a minimal surface of general type with $\chi=K^2=1$ but with $h^{01}\neq0$. We prove that such surfaces fulfill $h^{01}=1$ and they can exist only over fields of positive characteristic at most 5. Like non-classical ... More
Algebraic Surfaces of General Type with Small c_1^2 in Positive CharacteristicFeb 19 2007Oct 26 2007We establish Noether's inequality for surfaces of general type in positive characteristic.Then we extend Enriques' and Horikawa's classification of surfaces on the Noether line, the so-called Horikawa surfaces. We construct examples for all possible numerical ... More
The Canonical Map and Horikawa Surfaces in Positive CharacteristicApr 10 2010Dec 20 2011We extend fundamental inequalities related to the canonical map of surfaces of general type to positive characteristic. Next, we classify surfaces on the Noether lines, i.e., even and odd Horikawa surfaces, in positive characteristic. We describe their ... More
Descent properties of equivariant K-theoryFeb 12 2010We show that equivariant K-theory satisfies descent with respect to the isovariant Nisnevich topology. The main step is to show that the isovariant Nisnevich topology is a regular, complete and bounded cd topology.
Simple groups of birational transformations in dimension twoFeb 26 2018We classify simple groups that act by birational transformations on compact complex K\"ahler surfaces. Moreover, we show that every finitely generated simple group that acts non-trivially by birational transformations on a projective surface over an arbitrary ... More