Results for "Max Mühlhäuser"
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Analyzing Business Process Anomalies Using AutoencodersMar 03 2018Businesses are naturally interested in detecting anomalies in their internal processes, because these can be indicators for fraud and inefficiencies. Within the domain of business intelligence, classic anomaly detection is not very frequently researched. ... More BINet: Multi-perspective Business Process Anomaly ClassificationFeb 08 2019In this paper, we introduce BINet, a neural network architecture for real-time multi-perspective anomaly detection in business process event logs. BINet is designed to handle both the control flow and the data perspective of a business process. Additionally, ... More I Trust my Zombies: A Trust-enabled BotnetDec 11 2017Defending against botnets has always been a cat and mouse game. Cyber-security researchers and government agencies attempt to detect and take down botnets by playing the role of the cat. In this context, a lot of work has been done towards reverse engineering ... More Element Abundances through the Cosmic AgesMar 12 2003The horizon for studies of element abundances has expanded dramatically in the last ten years. Once the domain of astronomers concerned chiefly with stars and nearby galaxies, this field has now become a key component of observational cosmology, as technological ... More Friendly Artificial Intelligence: the Physics ChallengeSep 02 2014Sep 03 2014Relentless progress in artificial intelligence (AI) is increasingly raising concerns that machines will replace humans on the job market, and perhaps altogether. Eliezer Yudkowski and others have explored the possibility that a promising future for humankind ... More Cosmological neutrino bounds for non-cosmologistsMar 24 2005I briefly review cosmological bounds on neutrino masses and the underlying gravitational physics at a level appropriate for readers outside the field of cosmology. For the case of three massive neutrinos with standard model freezeout, the current 95% ... More The importance of quantum decoherence in brain processesJul 05 1999Nov 10 1999Based on a calculation of neural decoherence rates, we argue that that the degrees of freedom of the human brain that relate to cognitive processes should be thought of as a classical rather than quantum system, i.e., that there is nothing fundamentally ... More On the dimensionality of spacetimeFeb 25 1997Apr 05 1997Some superstring theories have more than one effective low-energy limit, corresponding to classical spacetimes with different dimensionalities. We argue that all but the 3+1-dimensional one might correspond to ``dead worlds'', devoid of observers, in ... More How to make maps from CMB data without losing informationNov 18 1996Mar 17 1997The next generation of CMB experiments can measure cosmological parameters with unprecedented accuracy - in principle. To achieve this in practice when faced with such gigantic data sets, elaborate data analysis methods are needed to make it computationally ... More How did it all begin?Aug 20 2005How did it all begin? Although this question has undoubtedly lingered for as long as humans have walked the Earth, the answer still eludes us. Yet since my grandparents were born, scientists have been able to refine this question to a degree I find truly ... More Quantization and SemiclassicsSep 01 2010This course is aimed at graduate students in physics in mathematics and designed to give a comprehensive introduction to Weyl quantization and semiclassics via Egorov's theorem. Chapter 2 gives a quick overview of classical and quantum mechanics on R^d. ... More Modified logarithmic Sobolev inequalities for canonical ensemblesJun 06 2013Jun 19 2014In this paper, we prove modified logarithmic Sobolev inequalities for canonical ensembles with superquadratic single-site potential. These inequalities were introduced by Bobkov and Ledoux, and are closely related to concentration of measure and transport-entropy ... More Twisted K-theory, old and newJan 27 2007Aug 23 2007Twisted K-theory has its origins in the author's PhD thesis [27] : http://www.numdam.org/item?id=ASENS_1968_4_1_2_161_0 and in the paper with P. Donovan http://www.numdam.org/item?id=PMIHES_1970__38__5_0 The objective of this paper is to revisit the subject ... More Higher-order Stein kernels for Gaussian approximationDec 06 2018We introduce higher-order Stein kernels relative to the standard Gaussian measure, which generalize the usual Stein kernels by involving higher-order derivatives of test functions. We relate the associated discrepancies to various metrics on the space ... More Over-Approximation of Fluid ModelsMay 01 2017May 01 2019Fluid models are a popular formalism in the quantitative modeling of biochemical systems and analytical performance models. The main idea is to approximate a large-scale Markov chain by a compact set of ordinary differential equations (ODEs). Even though ... More Simulating Linear Logic in 1-Only Linear LogicSep 09 2017Linear Logic was introduced by Girard as a resource-sensitive refinement of classical logic. It turned out that full propositional Linear Logic is undecidable (Lincoln, Mitchell, Scedrov, and Shankar) and, hence, it is more expressive than (modalized) ... More Flat Space Limit of (Higher-Spin) Cardy FormulaAug 29 2014Apr 18 2015In this note I derive the flat space limit of the modified Cardy formula associated with inner horizons and show that it reproduces the correct Galilean conformal field theory counting of flat space cosmology microstates. l also determine the entropy ... More Return Probabilities of Random WalksDec 14 2015Associated to a random walk on $\mathbb{Z}$ and a positive integer $n$, there is a return probability of the random walk returning to the origin after $n$ steps. An interesting question is when the set of return probabilities uniquely determines the random ... More Splittings of generalized Baumslag-Solitar groupsFeb 02 2005Mar 11 2006We study the structure of generalized Baumslag-Solitar groups from the point of view of their (usually non-unique) splittings as fundamental groups of graphs of infinite cyclic groups. We find and characterize certain decompositions of smallest complexity ... More On uniqueness of JSJ decompositions of finitely generated groupsOct 17 2001May 22 2003We give an example of two JSJ decompositions of a group that are not related by conjugation, conjugation of edge-inclusions, and slide moves. This answers the question of Rips and Sela stated in "Cyclic splittings of finitely presented groups and the ... More Deformation and rigidity of simplicial group actions on treesJul 02 2001May 08 2002We study a notion of deformation for simplicial trees with group actions (G-trees). Here G is a fixed, arbitrary group. Two G-trees are related by a deformation if there is a finite sequence of collapse and expansion moves joining them. We show that this ... More A Free Boundary Problem for the Parabolic Poisson KernelOct 19 2015We study parabolic chord arc domains, introduced by Hofmann, Lewis and Nystr\"om, and prove a free boundary regularity result below the continuous threshold. More precisely, we show that a Reifenberg flat, parabolic chord arc domain whose Poisson kernel ... More Partial flag incidence algebrasMay 05 2016The $n^{th}$ partial flag incidence algebra of a poset $P$ is the set of functions from $P^n$ to some ring which are zero on non-partial flag vectors. These partial flag incidence algebras for $n>2$ are not commutative, not unitary, and not associative. ... More Two-parameter Asymptotics in Magnetic Weyl CalculusSep 18 2008May 28 2010This paper is concerned with small parameter asymptotics of magnetic quantum systems. In addition to a semiclassical parameter \eps, the case of small coupling $\lambda$ to the magnetic vector potential naturally occurs in this context. Magnetic Weyl ... More Genealogical distance under selectionApr 21 2018We study the genealogical distance of two randomly chosen individuals in a population that evolves according to a two type Moran model with mutation and selection. We prove that this distance is stochastically smaller than the corresponding distance in ... More On Regularity of J-holomorphic MapsSep 03 2014We provide a short proof that an $L^2_1$ and $J$-holomorphic curve is in fact smooth. As an application, we deduce a removal of singularity theorem for curves of finite energy. Exploiting the Statistics of Learning and InferenceFeb 26 2014Mar 04 2014When dealing with datasets containing a billion instances or with simulations that require a supercomputer to execute, computational resources become part of the equation. We can improve the efficiency of learning and inference by exploiting their inherent ... More Practical Issues in Constructing a Bayes' Belief NetworkMar 27 2013Bayes belief networks and influence diagrams are tools for constructing coherent probabilistic representations of uncertain knowledge. The process of constructing such a network to represent an expert's knowledge is used to illustrate a variety of techniques ... More The First Galaxies: Clues from Element AbundancesJan 06 2000It has recently become possible to measure directly the abundances of several chemical elements in a variety of environments at redshifts up to z = 5. In this review I summarise the latest observations of Lyman break galaxies, damped Lyman alpha systems ... More Deuterium at High Redshifts: Recent Advances and Open IssuesJan 19 2006Among the light elements created in the Big Bang, deuterium is one of the most difficult to detect but is also the one whose abundance depends most sensitively on the density of baryons. Thus, although we still have only a few positive identifications ... More How to measure CMB power spectra without losing informationNov 21 1996Mar 12 1997A new method for estimating the angular power spectrum C_l from cosmic microwave background (CMB) maps is presented, which has the following desirable properties: (1) It is unbeatable in the sense that no other method can measure C_l with smaller error ... More Nuclear War from a Cosmic PerspectiveMay 01 2015May 21 2015I discuss the impact of computer progress on nuclear war policy, both by enabling more accurate nuclear winter simulations and by affecting the probability of war starting accidentally. I argue that from a cosmic perspective, humanity's track record of ... More What does inflation really predict?Oct 12 2004Mar 11 2005If the inflaton potential has multiple minima, as may be expected in, e.g., the string theory "landscape", inflation predicts a probability distribution for the cosmological parameters describing spatial curvature (Omega_tot), dark energy (rho_Lambda, ... More Rational curves in the moduli of supersingular K3 surfacesJul 30 2015We show how to construct non-isotrivial families of supersingular K3 surfaces over rational curves using a relative form of the Artin-Tate isomorphism and twisted analogues of Bridgeland's results on moduli spaces of stable sheaves on elliptic surfaces. ... More Differential Equations of Mathematical PhysicsAug 16 2015These lecture notes for the course APM 351 at the University of Toronto are aimed at mathematicians and physicists alike. It is not meant as an introductory course to PDEs, but rather gives an overview of how to view and solve differential equations that ... More The Large Hadron Electron Collider ProjectAug 20 2009A Conceptual Design Report (CDR) for the Large Hadron Electron Collider, the LHeC, is being prepared, to which an introduction was given for the plenary panel discussion on the future of deep inelastic scattering held at DIS09. This is briefly summarised ... More Twisted bundles and twisted K-theoryDec 12 2010We offer here a more direct approach to twisted K-theory, based on the notion of twisted vector bundles (of finite or infinite dimension) and of twisted principal bundles. This is closeely related to the classical notion ot torsors and bundles of modules ... More Le theoreme de periodicite en K-theorie hermitienneOct 26 2008Bott periodicity plays an important role in topological K-theory. The purpose of this paper is to extend the periodicity theorem in a discrete context, where all classical groups are involved and not just the general linear group. The present paper generalizes ... More Clifford modules and twisted K-theoryJan 17 2008The purpose of this shord paper is to make the link between the fundamental work of Atiyah, Bott and Shapiro (MR0167985/29/5250) and twisted K-theory (MR0282363/43/8075). This link was implicit for a long time in the literature (for the description of ... More The pentagram map and Y-patternsMay 04 2010Apr 15 2011The pentagram map, introduced by R. Schwartz, is defined by the following construction: given a polygon as input, draw all of its "shortest" diagonals, and output the smaller polygon which they cut out. We employ the machinery of cluster algebras to obtain ... More Decompositions of Kac-Moody groupsAug 18 2017Let $G$ be a split (minimal) Kac-Moody group over $\mathbb{R}$ or $\mathbb{C}$ with maximal torus $T$, and let $\theta$ be a Cartan-Chevalley involution of $G$, twisted by complex conjugation, and satisfying that $\theta(T)=T$. Furthermore, let $K$ be ... More The limit point of the pentagram mapJul 07 2017The pentagram map is a discrete dynamical system defined on the space of polygons in the plane. In the first paper on the subject, R. Schwartz proved that the pentagram map produces from each convex polygon a sequence of successively smaller polygons ... More Almost Primes in Thin Orbits of Pythagorean TrianglesMay 17 2016Let $F=x^2+y^2-z^2$, $x_0 \in \mathbb{Z}^3$ primitive with $F(x_0)=0$, and $\Gamma \leq SO_F(\mathbb{Z})$ be a finitely generated thin subgroup. We consider the resulting thin orbits of Pythagorean triples $x_0 \cdot \Gamma$ - specifically which hypotenuses, ... More Modeling $237$ Lyman-$α$ spectra of the MUSE-Wide surveySep 20 2017We compare $237$ Lyman-$\alpha$ (Ly$\alpha$) spectra of the "MUSE-Wide survey" (Herenz et al. 2017) to a suite of radiative transfer simulations consisting of a central luminous source within a concentric, moving shell of neutral gas, and dust. This six ... More Twisted sheaves and the period-index problemNov 09 2005May 25 2007We use twisted sheaves and their moduli spaces to study the Brauer group of a scheme. In particular, we (1) show how twisted methods can be efficiently used to re-prove the basic facts about the Brauer group and cohomological Brauer group (including Gabber's ... More Derivation degree sequences of non-free arrangementsJul 19 2018In this note we study the logarithmic derivation module of a non-free arrangement. We prove a generalized addition theorem for all arrangements. This addition theorem allows us to find various relationships between non-free arrangements, free arrangements ... More Markov chains under nonlinear expectationMar 09 2018In this paper, we consider nonlinear continuous-time Markov chains with a finite state space. We define so-called $Q$-operators as an extension of $Q$-matrices to a nonlinear setup, where the nonlinearity is due to parameter uncertainty. The main result ... More Moduli of twisted orbifold sheavesMar 23 2008Feb 02 2010We study stacks of slope-semistable twisted sheaves on orbisurfaces with projective coarse spaces and prove that in certain cases they have many of the asymptotic properties enjoyed by the moduli of slope-semistable sheaves on smooth projective surfaces. ... More Remarks on the stack of coherent algebrasMar 02 2006Jun 20 2006We consider the stack of coherent algebras with proper support, a moduli problem generalizing Alexeev and Knutson's stack of branchvarieties to the case of an Artin stack. The main results are proofs of the existence of Quot and Hom spaces in greater ... More Fast MLE Computation for the Dirichlet MultinomialMay 01 2014Given a collection of categorical data, we want to find the parameters of a Dirichlet distribution which maximizes the likelihood of that data. Newton's method is typically used for this purpose but current implementations require reading through the ... More Cycles positifs dans les variétés abéliennesSep 12 2011Sep 13 2011In the first part, we study the structure of the R-algebra generated by the Hodge classes on the self-product A^e of a very general principally polarized abelian variety A. In the second part, we compare various notions of positivity for cycles of higher ... More Improved Measures of Integrated InformationJan 11 2016Jul 18 2016Although there is growing interest in measuring integrated information in computational and cognitive systems, current methods for doing so in practice are computationally unfeasible. Existing and novel integration measures are investigated and classified ... More Comparing and combining CMB datasetsSep 01 1998Feb 08 1999One of the best ways of spotting previously undetected systematic errors in CMB experiments is to compare two independent observations of the same region. We derive a set of tools for comparing and combining CMB data sets, applicable also in the common ... More Removing real-world foregrounds from CMB mapsDec 03 1997Feb 20 1998Most work on foreground removal has treated the case where the frequency dependence of all components is perfectly known and independent of position. In contrast, real-world foregrounds are generally not perfectly correlated between frequencies, with ... More Measuring cosmological parameters with galaxy surveysJun 19 1997Dec 16 1997We assess the accuracy with which future galaxy surveys can measure cosmological parameters by deriving a handy approximation that we validate numerically. We find that galaxy surveys are quite complementary to future Cosmic Microwave Background (CMB) ... More CMB mapping experiments: a designer's guideMay 24 1997Jul 29 1997We apply state-of-the art data analysis methods to a number of fictitious CMB mapping experiments, including 1/f noise, distilling the cosmological information from time-ordered data to maps to power spectrum estimates, and find that in all cases, the ... More Does the universe in fact contain almost no information?Mar 07 1996At first sight, an accurate description of the state of the universe appears to require a mind-bogglingly large and perhaps even infinite amount of information, even if we restrict our attention to a small subsystem such as a rabbit. In this paper, it ... More The Mathematical UniverseApr 05 2007Oct 08 2007I explore physics implications of the External Reality Hypothesis (ERH) that there exists an external physical reality completely independent of us humans. I argue that with a sufficiently broad definition of mathematics, it implies the Mathematical Universe ... More Parallel UniversesFeb 07 2003I survey physics theories involving parallel universes, which form a natural four-level hierarchy of multiverses allowing progressively greater diversity. Level I: A generic prediction of inflation is an infinite ergodic universe, which contains Hubble ... More ESTIMATING MICROWAVE POWER SPECTRAFeb 06 1995A new method for estimating the power spectrum $C_l$ from cosmic microwave background (CMB) maps was recently presented by the author and applied to the 2 year COBE data. It was found that the spectral resolution $\Delta l$ for COBE could be more than ... More From algebraic K-theory to hermitian K-theorySep 26 2005We introduce a new morphism between algebraic and hermitian K-theory. The topological analog is the Adams operation in real K-theory. From this morphism, we deduce a lower bound for the higher algebraic K-theory of a ring A in terms of the classical Witt ... More Future Deep Inelastic Scattering with the LHeCFeb 12 2018For nearly a decade, Guido Altarelli accompanied the Large Hadron electron Collider project, as invited speaker, referee and member of the International Advisory Committee. This text summarises the status and prospects of the development of the LHeC, ... More Optimal Thrust Level for Orbit InsertionApr 14 2016The minimum-fuel orbital transfer is analyzed in the case of a launcher upper stage using a constantly thrusting engine. The thrust level is assumed to be constant and its value is optimized together with the thrust direction. A closed-loop solution for ... More Stabilization of the Witt groupSep 27 2005Using an idea due to R.Thomason, we define a "homology theory" on the category of rings which satisfies excision, exactness, homotopy (in the algebraic sense) and periodicity of order 4. For regular noetherian rings, we find P. Balmer's higher Witt groups. ... More General Boundary Quantum Field Theory in Anti de Sitter SpacetimesFeb 03 2016Jun 09 2016We mainly study real Klein-Gordon theory on Anti de Sitter spacetimes, and apply the General Boundary Formulation (GBF) of Quantum Theory in order to compute a radial S-matrix. We consider first the classical theory, giving a complete list of Klein-Gordon ... More A Two-Phase Free Boundary Problem for Harmonic MeasureSep 15 2014Sep 27 2016We study a 2-phase free boundary problem for harmonic measure first considered by Kenig and Toro and prove a sharp H\"older regularity result. The central difficulty is that there is no a priori non-degeneracy in the free boundary condition. Thus we must ... More