Results for "Florian Mehats"

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Dimension reduction for rotating Bose-Einstein condensates with anisotropic confinementJul 10 2015We consider the three-dimensional time-dependent Gross-Pitaevskii equation arising in the description of rotating Bose-Einstein condensates and study the corresponding scaling limit of strongly anisotropic confinement potentials. The resulting effective ... More
Nonlinear stability criteria for the HMF ModelSep 29 2015We study the nonlinear stability of a large class of inhomogeneous steady state solutions to the Hamiltonian Mean Field (HMF) model. Under a simple criterion, we prove the nonlinear stability of steady states which are decreasing functions of the microscopic ... More
Orbital stability of spherical galactic modelsJul 23 2010We consider the three dimensional gravitational Vlasov Poisson system which is a canonical model in astrophysics to describe the dynamics of galactic clusters. A well known conjecture is the stability of spherical models which are nonincreasing radially ... More
A new variational approach to the stability of gravitational systemsApr 16 2009Mar 05 2010We consider the three dimensional gravitational Vlasov Poisson system which describes the mechanical state of a stellar system subject to its own gravity. A well-known conjecture in astrophysics is that the steady state solutions which are nonincreasing ... More
Stable ground states for the relativistic gravitational Vlasov-Poisson systemFeb 05 2009We consider the three dimensional gravitational Vlasov-Poisson (GVP) system in both classical and relativistic cases. The classical problem is subcritical in the natural energy space and the stability of a large class of ground states has been derived ... More
Dimension reduction for anisotropic Bose-Einstein condensates in the strong interaction regimeMar 12 2014We study the problem of dimension reduction for the three dimensional Gross-Pitaevskii equation (GPE) describing a Bose-Einstein condensate confined in a strongly anisotropic harmonic trap. Since the gas is assumed to be in a strong interaction regime, ... More
Uniformly accurate methods for three dimensional Vlasov equations under strong magnetic field with varying directionJul 10 2019In this paper, we consider the three dimensional Vlasov equation with an inhomogeneous, varying direction, strong magnetic field. Whenever the magnetic field has constant intensity, the oscillations generated by the stiff term are periodic. The homogenized ... More
Uniformly accurate methods for Vlasov equations with non-homogeneous strong magnetic fieldFeb 08 2018In this paper, we consider the numerical solution of highly-oscillatory Vlasov and Vlasov-Poisson equations with non-homogeneous magnetic field. Designed in the spirit of recent uniformly accurate methods, our schemes remain insensitive to the stiffness ... More
A Framework for an Ego-centered and Time-aware Visualization of Relations in Arbitrary Data RepositoriesSep 27 2010Understanding constellations in large data collections has become a common task. One obstacle a user has to overcome is the internal complexity of these repositories. For example, extracting connected data from a normalized relational database requires ... More
p-Adic Lifting Problems and Derived EquivalencesFeb 08 2011Jan 08 2012For two derived equivalent $k$-algebras $\bar\Lambda$ and $\bar\Gamma$, we introduce a correspondence between $\OO$-orders reducing to $\bar\Lambda$ and $\OO$-orders reducing to $\bar\Gamma$. We outline how this may be used to transfer properties like ... More
Reverse mathematics of the finite downwards closed subsets of $\mathbb{N}^k$ ordered by inclusionOct 04 2016Oct 05 2016We show that the well-partial orderedness of the finite downwards closed subsets of $\mathbb{N}^k$ ,ordered by inclusion, is equivalent to the well-foundedness of the ordinal $\omega^{\omega^\omega}$. This was conjectured to be the case by Hatzikiriakou ... More
Vortex formation and dynamics in two-dimensional driven-dissipative condensatesJul 23 2016We investigate the real-time evolution of lattice bosons in two spatial dimensions whose dynamics is governed by a Markovian quantum master equation. We derive the generalization of the truncated Wigner approximation for open quantum many-body systems ... More
The Distribution of Optimal Strategies in Symmetric Zero-sum GamesNov 18 2016Given a skew-symmetric matrix, the corresponding two-player symmetric zero-sum game is defined as follows: one player, the row player, chooses a row and the other player, the column player, chooses a column. The payoff of the row player is given by the ... More
The integral polytope groupMay 04 2016We show that the Grothendieck group associated to integral polytopes in $\mathbb{R}^n$ is free-abelian by providing an explicit basis. Moreover, we identify the involution on this polytope group given by reflection about the origin as a sum of Euler characteristic ... More
Electroweak Symmetry Breaking without the $μ^2$ TermApr 01 2015May 12 2015We demonstrate that from a low energy perspective a viable electroweak symmetry breaking can be achieved without the (negative sign) $\mu^2$ mass term in the Higgs potential, thereby avoiding completely the appearance of relevant operators. We show that ... More
Thoughts on the Vacuum Energy in the Quantum N-PortraitAug 25 2014Oct 21 2015An application of the quantum N-portrait to the Universe is discussed, wherein the space-time geometry is understood as a Bose-Einstein condensate of N soft gravitons. If near or at the critical point of a quantum phase transition, indications are found ... More
An Indirect Handle on the Down-Quark Yukawa CouplingMay 31 2014To measure the Yukawa couplings of the up and down quarks, Y_{u,d}, seems to be far beyond the capabilities of current and (near) future experiments in particle physics. By performing a general analysis of the potential misalignment between quark masses ... More
Introduction to SARAH and related toolsSep 22 2015Mar 17 2016I give in this lecture an overview of the features of the Mathematica package SARAH, and explain how it can be used together with other codes to study all aspects of a BSM model. The focus will be on the description of the analytical calculations which ... More
A Supermanifold structure on Spaces of Morphisms between SupermanifoldsJun 29 2014The aim of this work is the construction of a "supermanifold of morphisms $X \rightarrow Y$", given two finite-dimensional supermanifolds $X$ and $Y$. More precisely, we will define an object $\underline{SC}^\infty(X,Y)$ in the category of supermanifolds ... More
Poisson Brackets in Kontsevich's "Lie World"Aug 31 2016In this note the notion of Poisson brackets in Kontsevich's "Lie World" is developed. These brackets can be thought of as "universally" defined classical Poisson structures, namely formal expressions only involving the structure maps of a quadratic Lie ... More
Vortex formation and dynamics in two-dimensional driven-dissipative condensatesJul 23 2016Nov 21 2016We investigate the real-time evolution of lattice bosons in two spatial dimensions whose dynamics is governed by a Markovian quantum master equation. We employ the Wigner-Weyl phase space quantization and derive the functional integral for open quantum ... More
Gaussian impurity moving through a Bose-Einstein superfluidOct 13 2016Apr 04 2017In this paper a Gaussian impurity moving through an equilibrium Bose-Einstein condensate at T = 0 is studied. The problem can be described by a Gross-Pitaevskii equation, which is solved perturbatively. The analysis is done for systems of 2 and 3 spatial ... More
Fully packed loop configurations: polynomiality and nested archesFeb 24 2017This article proves a conjecture by Zuber about the enumeration of fully packed loops (FPLs). The conjecture states that the number of FPLs whose link pattern consists of two noncrossing matchings which are separated by $m$ nested arches is a polynomial ... More
On $α$-largeness and the Paris-Harrington principle in $\mathrm{RCA}$ and $\mathrm{RCA}_0^{\displaystyle{*}}$Nov 28 2016We examine, within $\mathrm{RCA}$, the treatment by Ketonen and Solovay on the use of $\alpha$-largeness for giving an upper bound for the Paris-Harrington principle. We also show how to modify the arguments to work within $\mathrm{RCA}_0^{\displaystyle{*}}$. ... More
A new method to identify water masses -- a network-based analysis of oceanographic point measurement time seriesAug 23 2012This is a statistical analysis of the oceanographic time series measured across Fram Strait at a latitude of 78{\deg}50'N. Fram Strait is the deepest passage between the Arctic Ocean and the North Atlantic. There are up to 16 mooring lines with instruments ... More
The $L^2$-torsion polytope of amenable groupsApr 24 2017Feb 19 2019We introduce the notion of groups of polytope class and show that torsion-free amenable groups satisfying the Atiyah Conjecture possess this property. A direct consequence is the homotopy invariance of the $L^2$-torsion polytope among $G$-CW-complexes ... More
Scaling Laws for the Cosmological ConstantDec 01 2005Sep 06 2006We study the expansion of the universe at late times in the case that the cosmological constant obeys certain scaling laws motivated by renormalisation group running in quantum theories. The renormalisation scale is identified with the Hubble scale and ... More
The XL-mHG Test For Enrichment: A Technical ReportJul 28 2015Sep 24 2015The minimum hypergeometric test (mHG) is a powerful nonparametric hypothesis test to detect enrichment in ranked binary lists. Here, I provide a detailed review of its definition, as well as the algorithms used in its implementation, which enable the ... More
Kershaw closures for linear transport equations in slab geometry I: model derivationNov 09 2015Aug 02 2016This paper provides a new class of moment models for linear kinetic equations in slab geometry. These models can be evaluated cheaply while preserving the important realizability property, that is the fact that the underlying closure is non-negative. ... More
Monomial ideals and independence of $\mathrm{I}Σ_2$Mar 11 2016We show that a miniaturised version of Maclagan's theorem on monomial ideals is equivalent to $\mathrm{1}{-}\mathrm{Con}(\mathrm{I}\Sigma_2)$ and classify a phase transition threshold for this theorem. This work highlights the combinatorial nature of ... More
A Logic-Independent IDEOct 30 2014The author's MMT system provides a framework for defining and implementing logical systems. By combining MMT with the jEdit text editor, we obtain a logic-independent IDE. The IDE functionality includes advanced features such as context-sensitive auto-completion, ... More
The MMT API: A Generic MKM SystemJun 13 2013The MMT language has been developed as a scalable representation and interchange language for formal mathematical knowledge. It permits natural representations of the syntax and semantics of virtually all declarative languages while making MMT-based MKM ... More
Images of isogeny classes on modular elliptic curvesJul 20 2004Let K be a number field and E/K a modular elliptic curve, with modular parametrization $X_0(N) \to E$ defined over K. The purpose of this note is to study the images in E of classes of isogenous points in X_0(N).
CM points on products of Drinfeld modular curvesJul 20 2004Let X be a product of Drinfeld modular curves over a general base ring A of odd characteristic. We classify those subvarieties of X which contain a Zariski-dense set of CM points. This is an analogue of the Andr\'e-Oort conjecture. As an application, ... More
Calabi-Yau orbifolds over Hitchin basesJul 13 2018Any irreducible Dynkin diagram $\Delta$ is obtained from an irreducible Dynkin diagram $\Delta_h$ of type $\mathrm{ADE}$ by folding via graph automorphisms. For any simple complex Lie group $G$ with Dynkin diagram $\Delta$ and compact Riemann surface ... More
Counterexamples to the topological Tverberg conjectureFeb 01 2015Nov 13 2015The "topological Tverberg conjecture" by B\'ar\'any, Shlosman and Sz\H{u}cs (1981) states that any continuous map of a simplex of dimension $(r-1)(d+1)$ to $\mathbb{R}^d$ maps points from $r$ disjoint faces of the simplex to the same point in $\mathbb{R}^d$. ... More
Reverse mathematics of the relativised fast growing hierarchyAug 18 2016A short note on the reverse mathematical status of the totality of the relativised fast growing hierarchy.
On the $k$-Semispray of Nonlinear Connections in $k$-Tangent Bundle GeometryJan 05 2016In this paper we present a method by which is obtained a sequence of $k$-semisprays and two sequences of nonlinear connections on the $k$-tangent bundle $T^kM$, starting from a given one. Interesting particular cases appear for Lagrange and Finsler spaces ... More
Almost complex structures on the cotangent bundleJul 04 2005Jan 04 2006We construct some lift of an almost complex structure to the cotangent bundle, using a connection on the base manifold. This generalizes the complete lift defined by I.Sato and the horizontal lift introduced by K.Yano and S.Ishihara. We study some geometric ... More
The Polynomial Complexity of Vector Addition Systems with StatesJul 01 2019Vector addition systems are an important model in theoretical computer science and have been used in a variety of areas. In this paper, we consider vector addition systems with states over a parameterized initial configuration. For these systems, we are ... More
Algebraic approximation of Kähler threefoldsDec 07 2011In the present work, we investigate existence of deformations and algebraic approximability for certain uniruled K\"ahler threefolds. In the first part, we establish existence of infinitesimal deformations for all conic bundles with relative Picard number ... More
Breaking graph symmetries by edge colouringsApr 27 2016The distinguishing index $D'(G)$ of a graph $G$ is the least number of colours needed in an edge colouring which is not preserved by any non-trivial automorphism. Broere and Pil\'sniak conjectured that if every non-trivial automorphism of a countable ... More
On an explicit lower bound for the star discrepancy in three dimensionsFeb 03 2016Oct 05 2016Following a result of D.~Bylik and M.T.~Lacey from 2008 it is known that there exists an absolute constant $\eta>0$ such that the (unnormalized) $L^{\infty}$-norm of the three-dimensional discrepancy function, i.e, the (unnormalized) star discrepancy ... More
On spanning tree packings of highly edge connected graphsSep 30 2011Sep 18 2013We prove a refinement of the tree packing theorem by Tutte/Nash-Williams for finite graphs. This result is used to obtain a similar result for end faithful spanning tree packings in certain infinite graphs and consequently to establish a sufficient Hamiltonicity ... More
BFV-complex and higher homotopy structuresNov 29 2006Oct 14 2008We present a connection between the BFV-complex (abbreviation for Batalin-Fradkin-Vilkovisky complex) and the so-called strong homotopy Lie algebroid associated to a coisotropic submanifold of a Poisson manifold. We prove that the latter structure can ... More
The unirationality of Hurwitz spaces of 6-gonal curves of small genusSep 16 2011Nov 16 2012In this short note we prove the unirationality of Hurwitz spaces of 6-gonal curves of genus $g$ with $5\leq g\leq 28$ or $g=30,31,33,35,36,40,45$. Key ingredient is a liaison construction in $\PP^1 \times \PP^2$. By semicontinuity, the proof of the dominance ... More
An Application of Fixed-point Theory to Probabilistic Social ChoiceOct 22 2014Nov 26 2014The purpose of this note is to prove the existence of a randomized mechanism, a social decision scheme (SDS), with desirable fairness, efficiency, and strategyproofness properties unmatched by all known SDSs. In particular, we disprove a conjecture by ... More
Exploring new models in all detail with SARAHMar 13 2015I give an overview about the features the Mathematica package SARAH provides to study new models. In general, SARAH can handle a wide range of models beyond the MSSM coming with additional chiral superfields, extra gauge groups, or distinctive features ... More
From Superpotential to Model Files for FeynArts and CalcHep/CompHepSep 15 2009SARAH is a Mathematica package for building and studying supersymmetric models. It calculates for a given superpotential and gauge sector the full Lagrangian of a model. With the new version of SARAH it is possible to calculate automatically all interactions ... More
Warum Astrologie nicht funktionieren kannAug 28 2011There exists many different versions of astrology that are different from each other and sometimes even in conflict with each other. But the basis of every astrological system is the assumption of a connection between the motion of celestial bodies and ... More
Schwinger effect in inhomogeneous electric fieldsJun 29 2011The vacuum of quantum electrodynamics is unstable against the formation of many-body states in the presence of an external electric field, manifesting itself as the creation of electron-positron pairs (Schwinger effect). This effect has been a long-standing ... More
Gaussian impurity moving through a Bose-Einstein superfluidOct 13 2016In this paper a Gaussian impurity moving through an equilibrium Bose-Einstein condensate at T = 0 is studied. The problem can be described by a Gross-Pitaevskii equation, which is solved perturbatively. The analysis is done for systems of 2 and 3 spatial ... More
Cosmology with the 6-degree Field Galaxy SurveyMar 13 2013This thesis presents the analysis of the clustering of galaxies in the 6dF Galaxy Survey (6dFGS). At large separation scales the baryon acoustic oscillation (BAO) signal is detected which allows to make an absolute distance measurement at $z_{\rm eff} ... More
The p-adic group ring of SL_2(p^f)Jan 31 2013In this article we show that the $\Z_p[\zeta_{p^f-1}]$-order $\Z_p[\zeta_{p^f-1}]\SL_2(p^f)$ can be recognized among those orders whose reduction modulo $p$ is isomorphic to $\F_{p^f}\SL_2(p^f)$ using only ring-theoretic properties (in other words we ... More
A finiteness condition on local cohomology in positive characteristicJan 25 2011Apr 25 2011In this paper we present a condition on a local Cohen-Macaulay F-injective ring of positive characteristic $p > 2$ which implies that its top local cohomology module with support in the maximal ideal has finitely many Frobenius compatible submodules.
Random Fruits on the Zielonka TreeFeb 16 2009Stochastic games are a natural model for the synthesis of controllers confronted to adversarial and/or random actions. In particular, $\omega$-regular games of infinite length can represent reactive systems which are not expected to reach a correct state, ... More
Galois groups associated to generic Drinfeld modules and a conjecture of AbhyankarMar 10 2013Aug 19 2015Let $\phi$ be a rank $r$ Drinfeld $\BF_q[T]$-module determined by $\phi_T(X) = TX+g_1X^q+...+g_{r-1}X^{q^{r-1}}+X^{q^r}$, where $g_1,...,g_{r-1}$ are algebraically independent over $\BF_q(T)$. Let $N\in\BF_q[T]$ be a polynomial, and $k/\BF_q$ an algebraic ... More
Statistical analysis of a subset of the string theory landscapeOct 20 2008An analysis of a special class of type II string theory compactifications is presented. We focus on recent work in one particular orientifold background of intersecting brane models and the resulting four dimensional gauge group and matter content. Special ... More
Gauge sector statistics of intersecting D-brane modelsAug 31 2006Mar 02 2007In this article, which is based on the first part of my PhD thesis, I review the statistics of the open string sector in T^6/(Z_2xZ_2) orientifold compactifications of the type IIA string. After an introduction to the orientifold setup, I discuss the ... More
Phenomenology of jet physics in the BFKL formalism at NLOMar 19 2007We study jet physics in the high energy regime of QCD. Based on the NLO BFKL equation, we construct a vertex for the production of a jet at central rapidity in k_T-factorization. A jet algorithm is introduced, and we take special care of the separation ... More
On "finitary" Ramsey's theoremAug 09 2015Jul 05 2016We examine a version of Ramsey's theorem based on Tao, Gaspar and Kohlenbach's "finitary" infinite pigeonhole principle.We will show that the "finitary" infinite Ramsey's theorem naturally gives rise to statements at the level of the infinite Ramsey's ... More
Lower bounds on the size of general Schrödinger-cat states from experimental dataOct 11 2016Oct 12 2016Experimental progress with meso- and macroscopic quantum states (i.e., general Schrodinger-cat states) was recently accompanied by theoretical proposals on how to measure the merit of these efforts. So far, experiment and theory were disconnected as theoretical ... More
Total weight choosability in HypergraphsDec 22 2013A total weighting of the vertices and edges of a hypergraph is called vertex-coloring if the total weights of the vertices yield a proper coloring of the graph, i.e., every edge contains at least two vertices with different weighted degrees. In this note ... More
A note on the geometry of pseudoconvex domains of finite type in almost complex manifoldsAug 17 2010Let $D=\{\rho<0\}$ be a smooth domain of finite type in an almost complex manifold (M,J) of real dimension four. We assume that the defining function $\rho$ is J-plurisubharmonic on a neighborhood of $\overline{D}$. We study the asymptotic behavior of ... More
On pairs of p-adic analogues of the conjectures of Birch and Swinnerton-DyerNov 06 2012Dec 31 2015For a weight two modular form and a good prime $p$, we construct a vector of Iwasawa functions $(L_p^\sharp,L_p^\flat)$. In the elliptic curve case, we use this vector to put the $p$-adic analogues of the conjectures of Birch and Swinnerton-Dyer for ordinary ... More
Tutorial to SARAHMar 18 2016I give in this brief tutorial a short practical introduction to the Mathematica package SARAH. First, it is shown how an existing model file can be changed to implement a new model in SARAH. In the second part, masses, vertices and renormalisation group ... More
Intrinsic bottom and its impact on heavy new physics at the LHCJan 12 2016Heavy quark parton distribution functions (PDFs) play an important role in several Standard Model and New Physics processes. Most analyses rely on the assumption that the charm and bottom PDFs are generated perturbatively by gluon splitting and do not ... More
On pairs of p-adic L-functions for weight two modular formsDec 31 2015The point of this paper is to give an explicit p-adic analytic construction of two Iwasawa functions L_p^\sharp(f,T) and L_p^\flat(f,T) for a weight two modular form \sum a_n q^n and a good prime p. This generalizes work of Pollack who worked in the supersingular ... More
Twist-Deformed Lorentzian Heisenberg-AlgebrasAug 10 2006The Moyal-Weyl quantization procedure is embedded into the twist formalism of vector fields on phase space. Double application of twists provide most general deformations of Minkowskian Heisenberg-algebras and corresponding quantizations of the Lorentz-algebra. ... More
Total Edge Irregularity Strength of Large GraphsJun 23 2010Let $m:=|E(G)|$ sufficiently large and $s:=(m-1)/3$. We show that unless the maximum degree $\Delta > 2s$, there is a weighting $w:E\cup V\to \{0,1,...,s\}$ so that $w(uv)+w(u)+w(v)\ne w(u'v')+w(u')+w(v')$ whenever $uv\ne u'v'$ (such a weighting is called ... More
Pro-l birational anabelian geometry over algebraically closed fields IJul 05 2003We consider function fields of transcendence degree at least 2 over algebraic closures of finite fields, and describe a functorial way to recover such function fields form their pro-l Galois theory.
Combined degree and connectivity conditions for H-linked graphsJun 07 2012For a given multigraph H, a graph G is H-linked, if |G| \geq |H| and for every injective map {\tau}: V (H) \rightarrow V (G), we can find internally disjoint paths in G, such that every edge from uv in H corresponds to a {\tau} (u) - {\tau} (v) path. ... More
The cosmological constant filter without big bang singularityAug 03 2011Oct 03 2011In the recently proposed cosmological constant (CC) filter mechanism based on modified gravity in the Palatini formalism, gravity in the radiation, matter and late-time de Sitter eras is insensitive to energy sources with the equation of state -1. This ... More
The cosmological constant and the relaxed universeOct 06 2010We study the role of the cosmological constant (CC) as a component of dark energy (DE). It is argued that the cosmological term is in general unavoidable and it should not be ignored even when dynamical DE sources are considered. From the theoretical ... More
Pseudoconvex regions of finite D'Angelo type in four dimensional almost complex manifoldsOct 08 2007Let D be a J-pseudoconvex region in a smooth almost complex manifold (M,J) of real dimension four. We construct a local peak J-plurisubharmonic function at every boundary point p of finite D'Angelo type. As applications we give local estimates of the ... More
On the Global Well-Posedness of the Inviscid Generalized Proudman-Johnson equation using flow map argumentsFeb 11 2019We reformulate the Generalized Proudman--Johnson (GPJ) equation with parameter a in Lagrangian variables, where it takes the form of an inhomogeneous Liouville equation. This allows us to provide an explicitformula for the flow map, up to the solution ... More
Review of Calculators for BSM Higgs bosonsNov 20 2018We have reached a new era of particle physics in which the properties of the Higgs boson, in particular its mass, turned into precision observables. Therefore, it is necessary to have accurate predictions of these properties in models for new physics. ... More
Theoretical Constraints on Supersymmetric Models: Perturbative Unitarity vs. Vacuum StabilityNov 20 2018There are nowadays strong experimental constraints on supersymmetric theories from the Higgs measurements as well as from the null results in Sparticle searches. However, even the parameter spaces which are in agreement with experimental data can be further ... More
Distinguishing every finitely generated field of characteristic \neq2 by a single field axiomSep 03 2018Jan 11 2019We show that the isomorphy type of every finitely generated field $K$ with $\chr(K)\neq2$ is encoded by a \textit{\textbf{single\ha3explicit\ha3axiom}} $\istp K\!$ \textit{\textbf{in\ha3the\ha3language\ha3of\ha3fields}}, i.e., for all finitely generated ... More
Constant curvature metrics for Markov chainsDec 07 2017We consider metrics which are preserved under a $p$-Wasserstein transport map, up to a possible contraction. In the case $p=1$ this corresponds to a metric which is uniformly curved in the sense of coarse Ricci curvature. We investigate the existence ... More
xBIT: an easy to use scanning tool with machine learning abilitiesJun 07 2019xBIT is a tool for performing parameter scans in beyond the Standard Model theories. It's written in Python and fully open source. The main purpose of xBIT is to provide an easy to use tool to help phenomenologists with their daily task: exploring the ... More
A New Tool for the study of the CP-violating NMSSMMar 24 2015Jun 22 2015Supersymmetric extensions of the Standard Model open up the possibility for new types of CP-violation. We consider the case of the Next-to-Minimal Supersymmetric Standard Model where, beyond the phases from the soft lagrangian, CP-violation could enter ... More
Decays of a NMSSM CP-odd Higgs in the low-mass regionDec 20 2016Mar 27 2017A popular regime in the NMSSM parameter space involves a light CP-odd Higgs $A_1$. This scenario has consequences for e.g. light singlino Dark Matter annihilating in the $A_1$-funnel. In order to confront the pseudoscalar to experimental limits such as ... More
The Distribution of Optimal Strategies in Symmetric Zero-sum GamesNov 18 2016Jul 10 2017Given a skew-symmetric matrix, the corresponding two-player symmetric zero-sum game is defined as follows: one player, the row player, chooses a row and the other player, the column player, chooses a column. The payoff of the row player is given by the ... More
Palindromes and orderings in Artin groupsOct 11 2004Mar 14 2005The braid group $B_{n}$, endowed with Artin's presentation, admits two distinguished involutions. One is the anti-automorphism ${\rm{rev}}: B_{n} \to B_{n}$, $v \mapsto \bar{v}$, defined by reading braids in the reverse order (from right to left instead ... More
Forecasting Electricity Spot Prices using Lasso: On Capturing the Autoregressive Intraday StructureSep 07 2015Jan 23 2016In this paper we present a regression based model for day-ahead electricity spot prices. We estimate the considered linear regression model by the lasso estimation method. The lasso approach allows for many possible parameters in the model, but also shrinks ... More
Higher Heegner points on elliptic curves over function fieldsApr 16 2003Sep 22 2003Let E be a modular elliptic curve defined over a rational function field k of odd characteristic. We construct a sequence of Heegner points on E, defined over a $Z_p^{\infty}$-tower of finite extensions of k, and show that these Heegner points generate ... More
A Satake isomorphism in characteristic pOct 23 2009Feb 02 2011Suppose that G is a connected reductive group over a p-adic field F, that K is a hyperspecial maximal compact subgroup of G(F), and that V is an irreducible representation of K over the algebraic closure of the residue field of F. We establish an analogue ... More
Positive orthogonal functionsOct 16 2015The existence or non-existence of positive orthogonal functions for subspaces of almost periodic functions has important applications in studying the oscillatory behavior of vibrations. Cazenave, Haraux and Komornik have obtained a number of theorems ... More
A note on Gekeler's h-functionMay 09 2016We give a brief introduction to Drinfeld modular forms, concentrating on the many equivalent constructions of the form h of weight q+1 and type 1, to which we contribute some new characterizations involving Moore determinants, and an application to the ... More
Rooted induced trees in triangle-free graphsApr 09 2008Dec 15 2008For a graph $G$, let $t(G)$ denote the maximum number of vertices in an induced subgraph of $G$ that is a tree. Further, for a vertex $v\in V(G)$, let $t^v(G)$ denote the maximum number of vertices in an induced subgraph of $G$ that is a tree, with the ... More
$ψ$-Epistemic Models, Einsteinian Intuitions, and No-Gos. A Critical Study of Recent Developments on the Quantum StateMar 31 2016Apr 18 2016Quantum mechanics notoriously faces the measurement problem, the problem that if read thoroughly, it implies the nonexistence of definite outcomes in measurement procedures. A plausible reaction to this and to related problems is to regard a system's ... More
On affine Tverberg-type results without continuous generalizationFeb 17 2017Recent progress building on the groundbreaking work of Mabillard and Wagner has shown that there are important differences between the affine and continuous theory for Tverberg-type results. These results aim to describe the intersection pattern of convex ... More
Firefighting on trees and Cayley graphsJul 05 2017We study Hartnell's firefighter problem on infinite trees and characterise the branching number in terms of the firefighting game. Using our results about trees, we give a partial answer to a question of Mart\'inez-Pedroza concerning firefighting on Cayley ... More
Strong test modules and multiplier idealsMar 26 2003We introduce the notion of strong test module and show that a large number of such modules appear in the tight closure theory of complete domains: the test ideal (this has already been known), the parameter test module, and the module of relative test ... More
Exploring the Topological Entropy of Formal LanguagesJan 22 2018Apr 24 2019We introduce the notions of topological entropy of a formal language and of a topological automaton. We show that the entropy function is surjective and bound the entropy of languages accepted by deterministic {\epsilon}-free push-down automata with an ... More
An interlacing technique for spectra of random walks and its application to finite percolation clustersApr 25 2005Mar 29 2008A comparison technique for finite random walks on finite graphs is introduced, using the well-known interlacing method. It yields improved return probability bounds. A key feature is the incorporation of parts of the spectrum of the transition matrix ... More
Explicit Drinfeld moduli schemes and Abhyankar's generalized iteration conjectureMar 22 2015Aug 19 2015Let $k$ be a field containing $\mathbb{F}_q$. Let $\psi$ be a rank $r$ Drinfeld $\mathbb{F}_q[t]$-module determined by $\psi_t(X) = tX+a_1X^q+\cdots+a_{r-1}X^{q^{r-1}}+X^{q^r}$, where $t,a_1,\ldots,a_{r-1}$ are algebraically independent over $k$. Let ... More
The Picard group of an order and Külshammer reductionJul 13 2018Let $(K,\mathcal O,k)$ be a $p$-modular system and assume $k$ is algebraically closed. We show that if $\Lambda$ is an $\mathcal O$-order in a separable $K$-algebra, then $\textrm{Pic}_{\mathcal O}(\Lambda)$ carries the structure of an algebraic group ... More
Brownian Motions on Metric Graphs with Non-Local Boundary Conditions II: ConstructionMay 28 2018A pathwise construction of discontinuous Brownian motions on metric graphs is given for every possible set of non-local Feller-Wentzell boundary conditions. This construction is achieved by locally decomposing the metric graphs into star graphs, establishing ... More