Hwang–Mok rigidity of cominuscule homogeneous varieties in positive characteristic
Friday, 18.10.13, 10:00-11:00, Raum 404, Eckerstr. 1
Jun-Muk Hwang and Ngaiming Mok have proved the rigidity of\nirreducible Hermitian symmetric spaces of compact type under Kaehler degeneration. I adapt their argument to the algebraic setting in positive characteristic, where cominuscule homogeneous varieties serve as an analogue of Hermitian symmetric spaces. The main result gives an\nexplicit (computable in terms of Schubert calculus) lower bound on the characteristic of the base field, guaranteeing that a smooth projective family with cominuscule homogeneous generic fibre is isotrivial. The bound depends only on the type of the generic fibre, and on the degree of an invertible sheaf whose extension to the special fibre is very ample. An important part of the proof is a characteristic-free analogue of Hwang and Mok’s extension theorem for maps of Fano varieties of Picard number 1, a result I believe to be interesting in its own right.\n
Programmdiskussion
Monday, 21.10.13, 16:15-17:15, Raum 404, Eckerstr. 1
test
Thursday, 24.10.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Exterior power operations on Witt rings
Friday, 25.10.13, 10:00-11:00, Raum 404, Eckerstr. 1
The Witt ring of a field has a natural filtration by powers of the so-called fundamental ideal. We exhibit a possible generalization of this filtration to Grothendieck-Witt rings of vector bundles over a scheme or of representations of an affine algebraic group via exterior power operations. Our main technical result is that the resulting λ-structures are special. The talk will close with a few example calculations and many open question.
Risk aggregation with dependence uncertainty
Wednesday, 30.10.13, 16:15-17:15, Raum 232, Eckerstr. 1
Modeling inter-dependence between individual risks often faces statistical as well as probabilistic challenges. In this talk, we introduce a mathematical framework for the dependence uncertainty in risk aggregation, where the marginal distribution of individual risks are assumed known but the joint dependence structure is assumed to be unknown. We discuss past, ongoing and potential future research on convex orders, extreme scenarios, risk measures, and asymptotics related to depence uncertainty. The mathematical developments in this talk are mainly inspired by the concept of complete mixability.
tba
Wednesday, 30.10.13, 16:30-17:30, Raum 404, Eckerstr. 1
Thursday, 31.10.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Ueber mathematische Modelle zu Zweiphasen-Stroemungen.
Monday, 4.11.13, 14:00-15:00, Raum 414, Eckerstr. 1
Conformally flat cylinders without conjugate points
Monday, 4.11.13, 16:15-17:15, Raum 404, Eckerstr. 1
For surfaces without conjugate points, Eberhard Hopf's method leads to optimal rigidity results. The question arises of whether (a generalization of) the method is equally powerful in higher dimensions. We will investigate the case of conformally flat cylinders.
A generalization of Gromov's almost flat manifold theorem
Tuesday, 5.11.13, 16:00-17:00, Raum 404, Eckerstr. 1
Almost flat manifolds are the solutions of bounded size perturbations of the equation Sec = 0 (Sec is the sectional curvature). In a celebrated theorem, Gromov proved that the presence of an almost flat metric implies a precise topological description of the underlying manifold.\n\nDuring this talk we will explain how, under lower sectional curvature bounds, to impose an L1-pinching condition on the curvature is surprisingly rigid, leading indeed to the same conclusion as in Gromov's theorem under more relaxed curvature conditions (in particular, so weak that we are not allowed to use Ricci flow in the proof). We will describe which alternative techniques lead us to a successful proof, ans this will be sketched in detail. This is a joint work with B. Wilking.\n
Thursday, 7.11.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Fibered Derivators, (Co)homological Descent and the Six-Functor Formalism
Friday, 8.11.13, 10:15-11:15, Raum 404, Eckerstr. 1
Derivators have been introduced by Grothendieck, as one of his last mathematical contributions, to simplify, extend, and conceptually clarify the\nnotions of derived and triangulated categories. Extended to the context of fibered (multi-)categories (e.g. any kind of sheaves of abelian groups on spaces, schemes, stacks etc.)\nthe notion allows for a neat solution to problems of cohomological descent as well as homological descent. This gives an elegant way\nof extending the six-functor formalism of Grothendieck (which encodes, among other things, dualities like e.g. Serre duality, Poincar'e-Verdier duality)\nto stacks.
Trapped Reeb orbits do not imply periodic ones
Monday, 11.11.13, 16:15-17:15, Raum 404, Eckerstr. 1
Minimal hypersurfaces in manifolds with nonnegative Ricci curvature
Tuesday, 12.11.13, 16:00-17:00, Raum 404, Eckerstr. 1
In this talk, I would like to discuss minimal hypersurfaces in complete manifolds with nonnegative Ricci curvature and Euclidean volume growth. The existence of area minimizing hypersurfaces is strongly influenced by Ricci curvature of ambient manifolds, where our model spaces are the Euclidean cones over spheres of radius less than 1. Moreover, I would like to study minimal graphs in product manifolds, and talk about gradient estimates and Liouville type theorems for minimal graphic functions.\n\n
tba
Wednesday, 13.11.13, 16:00-17:00, Raum 404, Eckerstr. 1
Bayesian change-point problems in multidimensional diffusion models
Thursday, 14.11.13, 11:30-12:30, Raum 232, Eckerstr. 1
Thursday, 14.11.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Nichthomogene affine Flächen mit riesiger Automorphismengruppe
Friday, 15.11.13, 10:15-11:15, Raum 404, Eckerstr. 1
Developments in Medical Statistics 1963-2013
Friday, 15.11.13, 13:00-14:00, Otto - Krayer - Haus, Albertstr. 25
Berkovich Spaces
Monday, 18.11.13, 10:15-11:15, Raum 119, Eckerstr. 1
Euler Structures on Fibre Bundles
Monday, 18.11.13, 16:15-17:15, Raum 404, Eckerstr. 1
Berkovich Spaces II
Tuesday, 19.11.13, 10:15-11:15, SR 414
Definable valuation rings
Tuesday, 19.11.13, 16:15-17:15, Hörsaal II, Albertstr. 23b
Thursday, 21.11.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
A diagram algebra for categorifying gl(1|1)
Friday, 22.11.13, 10:15-11:15, Raum 404, Eckerstr. 1
Cones over metric measure spaces and the maximal diameter theorem
Monday, 25.11.13, 16:15-17:15, Raum 404, Eckerstr. 1
We briefly describe the definition of curvature-dimension bounds in the sense of Lott-Villani/Sturm (CD(K,N)) and recent results about Riemannian differential calculus for metric measure spaces. Then we present the following theorem: the cone over a metric measure space satisfies CD(KN,N-1) if and only if the underlying space satisfies CD(N-1,N). As consequence of this result and the Cheeger-Gigli-Gromoll splitting theorem we obtain a maximal diameter theorem in the context of metric measure spaces.
Berkovich Spaces III
Tuesday, 26.11.13, 10:15-11:15, SR 414
Non omega-categorical structures with finitely many reducts
Wednesday, 27.11.13, 16:30-17:30, Raum 404, Eckerstr. 1
Non omega-categorical structures with fintely many reducts
Wednesday, 27.11.13, 16:30-17:30, Raum 404, Eckerstr. 1
Berkovich Spaces IV
Thursday, 28.11.13, 10:15-11:15, SR 414
Higher Lie groupoids
Thursday, 28.11.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Lie groupoids are a fundamental part of the language of\ndifferential geometry: they bring both differentiable actions of Lie groups\nand foliations under a single roof. In complex geometry, they underly the\nwork of Kuranishi and others on moduli of holomorphic vector bundles. In\nthis talk, I will report on recent work (joint with Kai Behrend)\ngeneralizing the theory of Lie groupoids to higher groupoids - where the\nsymmetries have symmetries of their own, and so on. We will show how this\nyields a language for extending Kuranishi's ideas to the setting of\ncomplexes of holomorphic bundles (or better, of twisted complexes).\n
Friday, 29.11.13, 10:15-11:15, Raum 404, Eckerstr. 1
The geometry of singularities in the Minimal Model Program and applications to singular spaces with trivial canonical class
Friday, 29.11.13, 10:15-11:15, Raum 404, Eckerstr. 1
This talk surveys recent results on the singularities of\nthe Minimal Model Program and discusses applications to the study of\nvarieties with trivial canonical class. Comparing the étale fundamental\ngroup of a klt variety with that of its smooth locus, we show that any\nflat holomorphic bundle, defined on the smooth part of a projective\nklt variety is algebraic and extends across the singularities. This\nallows to generalise a famous theorem of Yau, which states that any\nRicci-flat Kähler manifold with vanishing second Chern class is an\nétale quotient of a torus.\n\nThis is joint work with Daniel Greb and Thomas Peternell\n
Chern-Weil theory for quasi-isomorphisms
Friday, 29.11.13, 14:15-15:15, Raum 404, Eckerstr. 1
Berkovich Spaces V
Monday, 2.12.13, 10:15-11:15, Raum 119, Eckerstr. 1
The Kähler-Einstein problem
Monday, 2.12.13, 16:15-17:15, Raum 404, Eckerstr. 1
This will be an overview of the Kähler-Einstein problem, including its very recent resolution in the positive case.
Berkovich Spaces VI
Tuesday, 3.12.13, 10:15-11:15, SR 414
Realization of aleph_k-free modules via Shelah's Easy Black Box
Wednesday, 4.12.13, 16:00-17:00, Raum 404, Eckerstr. 1
Realization of aleph_k-free modules with few endomorphisms via Shelah's Easy Black Box
Wednesday, 4.12.13, 16:00-17:00, Raum 404, Eckerstr. 1
Optimal feedback control for undamped wave equations by solving a HJB equation
Thursday, 5.12.13, 14:15-15:15, Fakultätsraum, Raum: 427 (Eckerstr. 1)
Thursday, 5.12.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Differential forms in the h-topology
Friday, 6.12.13, 10:15-11:15, Raum 404, Eckerstr. 1
The h-topology on the category of separated schemes of\nfinite type over a field of characteristic zero was\nintroduced by Voevodsky to study the homology of schemes. I\nwill discuss in my talk the sheaves of h-differential\nforms, i.e., the appropriate notion of differential forms\nin the h-topology. Subsequently I will study their\nbehaviour on rationally chain connected spaces and the\nconnection to algebraic de Rham cohomology. This is joint\nwork with Annette Huber-Klawitter.\n
Zeitstetige Moving-Average Prozesse und Anwendungen auf die Strompreismodellierung
Friday, 6.12.13, 11:30-12:30, Raum 404, Eckerstr. 1
A universal eta-Invariant for G2-Structures
Monday, 9.12.13, 16:00-17:00, Raum 404, Eckerstr. 1
In this talk I will give a short introduction to the exceptional Lie-group G2. Then I will motivate G2-structure with G2-manifolds, i. e. Riemannian manifolds with holonomy group G2, that are an exceptional case in the classification of Berger and allegedly have applications in physics. On these G2-structures Crowley and Nordström defined the nu-invariant with values in Z/48Z, which I will explain. The mod 3 reduction of the nu-invariant is a G2-bordism invariant and has been interpreted as a universal eta-invariant in my thesis.
tba
Monday, 9.12.13, 16:15-17:15, Raum 404, Eckerstr. 1
The first-order theory of universal specialisations of Zariski structures
Wednesday, 11.12.13, 16:30-17:30, Raum 404, Eckerstr. 1
Thursday, 12.12.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Graph algebras
Friday, 13.12.13, 10:15-11:15, Raum 404, Eckerstr. 1
From a graph (e.g., cities and flights between them) one can generate an algebra which captures the movements along the graph.\n\nThis talk is about one type of such correspondences, i.e., Leavitt path algebras.\n\nDespite being introduced only 8 years ago, Leavitt path algebras have arisen in a variety of different contexts as diverse as analysis, symbolic dynamics, noncommutative geometry and representation theory. In fact, Leavitt path algebras are algebraic counterpart to graph C*-algebras, which has become an area of intensive research. There are strikingly parallel similarities between these two theories. Even more surprisingly, one cannot (yet) obtain the results in one theory as a consequence of the other; the statements look the same, however the techniques to prove them are quite different (as the names suggest, one uses Algebra and other Analysis). These all suggest that there might be a bridge between Algebra and Analysis yet to be uncovered.\n\nIn this talk, we introduce Leavitt path algebras and then try to understand the behaviour and to classify them by means of (graded) K-theory. We will ask nice questions!\n
Cross-sectional Sampling, Bias and Dependence
Friday, 13.12.13, 11:30-12:30, Raum 404, Eckerstr. 1
Algebraic K-theory, eta-invariant and homology sphere
Monday, 16.12.13, 16:15-17:15, Raum 404, Eckerstr. 1
In this talk we will discuss how to use eta-invariant to find some geometric models for some algebraic K-groups.
Von Stühlen, Definitionen und Funktionen
Tuesday, 17.12.13, 19:30-20:30, Hörsaal II, Albertstr. 23b
Wenn das kein Integral ist, was ist es denn dann? Wie entstehen Konzepte in unserem Kopf? Lernen wir Begriffe wie Vokabeln einer Fremdsprache? \nDieser Vortrag spürt Antworten auf diese und weitere Fragen auf, um daraus mögliche Konsequenzen für den Mathematikunterricht abzuleiten. Dabei werden die Zuhörer zu einigen Versuchen mit Schuhen, Tafeln, Stühlen und Rechnern eingeladen, um die theoretischen Hintergründe sinnlich erfahrbar zu machen. \nInhaltliche und methodische Beispiele aus dem Unterricht konkretisieren abschließend die vorausentworfenen Überlegungen. \n
t.b.a.
Wednesday, 18.12.13, 16:30-17:30, Raum 404, Eckerstr. 1
Silver versus club-Silver in the generalized Cantor space
Wednesday, 18.12.13, 16:30-17:30, Raum 404, Eckerstr. 1
On buttons and balls that cannot run away
Thursday, 19.12.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
This lecture presents convex sets of constant width. They are\ncharacterized by the fact that any two nonidentical tangent lines or tangent\nplanes have the same distance from each other, but they are not necessarily\ndiscs (in the plane) or balls (in 3-space). I will show how such sets can be\nused to drill square holes, and that the ignorance of such sets had fatal\nconsequences in the American space flight program. I shall also report on a\nlong-standing open conjecture and its recent development. The talk contains\nalso some video clips and is suitable for a general audience with\nmathematical interest.
Friday, 20.12.13, 10:15-11:15, Raum 404, Eckerstr. 1
Thursday, 26.12.13, 17:00-18:00, Hörsaal II, Albertstr. 23b
Thursday, 2.1.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Tuesday, 7.1.14, 14:00-15:00, Raum 226, Hermann-Herder-Str. 10
The closure theorem for integer rectifiable currents
Tuesday, 7.1.14, 16:15-17:15, Raum 404, Eckerstr. 1
The Hurewicz dichotomy for generalized Baire spaces
Wednesday, 8.1.14, 16:00-17:00, Raum 404, Eckerstr. 1
Thursday, 9.1.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Friday, 10.1.14, 10:15-11:15, Raum 404, Eckerstr. 1
Uncertainty analyses in the systems biology using the profile likelihood
Friday, 10.1.14, 11:30-12:30, Raum 404, Eckerstr. 1
Some simple singularity theory
Monday, 13.1.14, 16:15-17:15, Raum 404, Eckerstr. 1
The closure theorem for integer rectifiable currents
Tuesday, 14.1.14, 16:15-17:15, Raum 404, Eckerstr. 1
"Kompetenzorientierter Mathematikunterricht" - Was kann das bedeuten?
Tuesday, 14.1.14, 19:30-20:30, Hörsaal II, Albertstr. 23b
Aktuelle Lehr- und Bildungspläne in Mathematik orientieren sich an den Bildungsstandards und sind „kompetenzorientiert“, d.h. Schülerinnen und Schüler sollen anhand von zentralen mathematischen Inhalten gewisse mathematische Fähigkeiten wie Argumentieren, Problemlösen oder Modellieren erwerben. Das A und O hierfür ist ein guter Mathematikunterricht. Im Vortrag werden anhand zweier Unterrichtsstunden bzw. -einheiten aus Klasse 8 (Realschule) bzw. Klasse 10 (Gymnasium) einige wesentliche Elemente eines qualitätsvollen, „kompetenzorientierten“ Mathematikunterrichts herausgearbeitet und erläutert. Dazu gehören u.a. die geistige Aktivierung aller Schülerinnen und Schüler sowie die Vermittlung von Strategien. Zudem wird aufgezeigt, wie wichtig diagnostische Kompetenzen der Lehrerinnen und Lehrer sind. Abschließend werden einige naheliegende Folgerungen für die Lehrerbildung gezogen.
Thursday, 16.1.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Classifying superconformal field theories via chiral rings
Monday, 20.1.14, 16:15-17:15, Raum 404, Eckerstr. 1
I will introduce some of the main mathematical ideas behind N=2 superconformal field theory, using the N=2 minimal models as a concrete example, and explore some of their connections to geometry. \n\nTo illustrate these ideas I will focus on the so-called "chiral rings", which arise from basic Lie algebra representation theory plus ideas from quantum field theory. I show how the chiral rings relate to Calabi-Yau geometry, then I'll describe how chiral rings appear in Cecotti and Vafa's famous ADE singularity classification of a special subclass of N=2 minimal models (those with "space-time supersymmetry"), and we'll briefly reacquaint ourselves with some other prominent appearances the ADE pattern in maths and physics.\n\nFinally I'll present the chiral rings of the entire class of N=2 minimal models (when the extra assumption of space-time supersymmetry is dropped) and report on ongoing work with K. Wendland concerning a geometric classification of these theories.\n
A Variant of the C0 Interior Penalty Method for the Biharmonic Equation
Tuesday, 21.1.14, 14:15-15:15, Raum 226, Hermann-Herder-Str. 10
We consider a symmetric interior penalty method for the Biharmonic Problem which weakly over-penalizes the jumps of the normal derivatives across element boundaries and which can handle meshes with hanging nodes. The notion of meshes generated by independent refinements will be introduced and a general analysis of piecewise H2-functions associated with those meshes will be presented. We derive a priori error estimates in the energy norm and the L2-norm for a class of meshes generated by independent refinements and demonstrate the performance by numerical results.
A Kinematic Formula for Hypersurfaces
Tuesday, 21.1.14, 16:15-17:15, Raum 404, Eckerstr. 1
The closure theorem for integer rectifiable currents
Tuesday, 21.1.14, 17:10-18:10, Raum 404, Eckerstr. 1
Finitely many near-coherence classes of ultrafilters
Wednesday, 22.1.14, 16:30-17:30, Raum 404, Eckerstr. 1
Using semigroups to study coupled cell networks
Thursday, 23.1.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Dynamical systems with a coupled cell network\nstructure arise in applications that range from statistical\nmechanics and electrical circuits to neural networks,\nsystems biology, power grids and the world wide web.\n A network structure can have a strong impact on the\nbehaviour of a dynamical system. For example, it has been\nobserved that networks can robustly exhibit (partial)\nsynchronisation, multiple eigenvalues and degenerate\nbifurcations. In this talk I will explain how semigroups\nand their representations can be used to understand and\npredict these phenomena. As an application of our theory, I\nwill discuss how a simple feed-forward motif can act as an\namplifier.\n This is joint work with Jan Sanders.
Lie subalgebras of vector fields and the Jacobian conjecture
Friday, 24.1.14, 10:15-11:15, Raum 404, Eckerstr. 1
Quantum Physics and Big Data
Friday, 24.1.14, 11:30-12:30, Raum 404, Eckerstr. 1
tba
Monday, 27.1.14, 16:15-17:15, Raum 404, Eckerstr. 1
Complex multiplication on abelian varieties
Monday, 27.1.14, 16:15-17:15, Raum 404, Eckerstr. 1
"Sharp Interface Limits of Diffuse Interface Models for Incompressible Two-Phase Flows"
Tuesday, 28.1.14, 14:15-15:15, Raum 226, Hermann-Herder-Str. 10
The compactness theorem for area minimizing currents
Tuesday, 28.1.14, 16:15-17:15, Raum 404, Eckerstr. 1
Methodos
Tuesday, 28.1.14, 19:30-20:30, Hörsaal II, Albertstr. 23b
Methodos ist eine Gruppe von Schülerinnen und Schülern, die sich selbstständig auf die externe Abiturprüfung in Baden-Württemberg vorbereiten. Sie übernehmen Planung und Organisation aller Aufgaben, die für diese Vorbereitung notwendig sind, weil sie ihr Lernen gestalten und für ihre Bildung selbstverantwortlich sein wollen. Dafür haben sie sich von der Regelschule abgemeldet. Sie mieten Unterrichtsräume und stellen Lehrer ein (und entlassen sie gegebenenfalls auch). Sie versuchen individuelles Lernen und Arbeiten in der Gruppe fruchtbar miteinander zu verbinden.\nSimon Valentin und Dieter Markert berichten aus Schüler- und Lehrerperspektive von ihren Erfahrungen bei Methodos.\n
Higher Tannaka duality and realizations of mixed motives
Thursday, 30.1.14, 11:00-12:00, Raum 218, Eckerstr. 1
Thursday, 30.1.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Tilting and Parity
Friday, 31.1.14, 10:15-11:15, Raum 404, Eckerstr. 1
In the representation theory of reductive groups in positive\ncharacteristic, there is a very special class of objects called tilting\nmodules. Two important theorems state that the class of tilting modules\nis closed under tensor product and restriction to Levi subgroups.\n\nSimilarly, on (generalized) flag varieties, there is a special class of\ngeometric objects called parity sheaves. I will explain two newer\ntheorems that are analogues of the tensor product and restriction\ntheorems mentioned above.\n\nThe main goal of the talk will be to explain how these two pictures fit\ntogether.\n\nThis is based on joint work with Daniel Juteau and Geordie Williamson.
tba
Monday, 3.2.14, 16:15-17:15, Raum 404, Eckerstr. 1
Eta-forms in family index theory
Monday, 3.2.14, 16:15-17:15, Raum 404, Eckerstr. 1
This talk will give a short introduction how the differential of the eta form gives the difference between the cohomological and the analytical index. Then we'll look at an example where the dimension of the kernel of the Dirac operator changes and see how this affects the eta-form.
Bad Wadge-like reducibilities on the Baire space and on arbitrary ultrametric Polish spaces
Wednesday, 5.2.14, 16:00-17:00, Raum 404, Eckerstr. 1
Weightless cohomology of algebraic varieties
Thursday, 6.2.14, 11:00-12:00, Raum 218, Eckerstr. 1
Using Morel's weight truncations in categories of mixed sheaves, we attach to any variety defined over complex numbers, over finite fields or even over a number field, a series of groups called the weightless cohomology groups . These lie between the usual cohomology and the intersection cohomology, have a natural ring structure, satisfy Kunneth, and are functorial for certain morphisms.\n The construction is motivic and naturally arises in the context of Shimura Varieties where they capture the cohomology of Reductive Borel Serre compactification. The construction also yields invariants of singularities associated with the combinatorics of the boundary divisors in any resolution.
Thursday, 6.2.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Motives of rigid analyic varieties over perfectoid fields
Friday, 7.2.14, 10:15-11:15, Raum 404, Eckerstr. 1
The aim of the talk is to outline the proof of the equivalence between the category of motives of rigid analytic varieties (defined by Ayoub adapting Voevodsky's construction) over a perfectoid field of mixed characteristic and over the associated (tilted) perfectoid field of equal characteristic. This can be considered as a motivic generalization of a theorem of Fontaine and Wintenberger regarding the isomorphism of the two absolute Galois groups. A main tool for constructing the equivalence is Scholze's theory of perfectoid spaces, which will also be briefly discussed.\n
Geometrisch-optische Illusionen und Riemannsche Geometrie
Friday, 7.2.14, 11:30-12:30, Raum 404, Eckerstr. 1
Vorstellung Masterarbeit
Monday, 10.2.14, 16:15-17:15, Raum 404, Eckerstr. 1
Bounded Hyperimaginaries
Wednesday, 12.2.14, 16:30-17:30, Raum 404, Eckerstr. 1
Thursday, 13.2.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
Friday, 14.2.14, 10:15-11:15, Raum 404, Eckerstr. 1
Bounded cohomology via partial differential equations
Monday, 17.2.14, 10:15-11:15, Raum 404, Eckerstr. 1
By the van Est isomorphism, continuous cohomology of simple Lie groups vanishes in degree greater than the dimension of the associated symmetric space. Monod conjectured that a similar vanishing theorem should hold for continuous bounded cohomology. In this talk, we will present a new technique that employs partial differential equations in order to explicitly construct primitives in the continuous bounded cohomology of Lie groups. As an application, we prove Monod's conjecture for SL(2,R) in degree four and discuss perturbations of the Spence-Abel functional equation for the dilogarithm function. This is joint work with Tobias Hartnick.\n
The asymptotic geometry of the moduli space of Higgs bundles over a Riemann surface
Tuesday, 18.2.14, 10:15-11:15, Raum 404, Eckerstr. 1
Soulé-elements, p-adic periods & an explicit reciprocity law
Wednesday, 19.2.14, 14:15-15:15, Raum 404, Eckerstr. 1
Coarse topology of leaves of foliations
Friday, 21.2.14, 10:15-11:15, Raum 404, Eckerstr. 1
Intersection theory on singular varieties
Tuesday, 25.2.14, 10:15-11:15, Hörsaal II, Albertstr. 23b
We introduce some ideas from motivic cohomology into the study of singular varieties. Our approach is modeled on the intersection homology of Goresky-MacPherson; our goal is to intersect cycles on a stratified singular variety provided the cycles do not meet the strata too badly. We define "perverse" analogues of Chow groups and motivic cohomology. Properties include homotopy invariance, a localization theorem, and a splitting theorem. As a consequence we obtain pairings between certain "perverse" cycle groups on a singular variety.\n\n
Monday, 3.3.14, 17:00-18:00, Hörsaal II, Albertstr. 23b
test
Multiple polylogarithm cycles and mixed Tate motives over the projective line minus three points
Monday, 17.3.14, 10:15-11:15, Raum 404, Eckerstr. 1
After introducing the multiple polylogarithms functions and the mixed Tate motive context,\nwe will present Bloch and Kritz description of motivic polylogarithms using algebraic cycles. More generally,\nwe will show how this approach can be generalized to multiple polylogarithms. We will insist on the geometric\nsituation and on some low weight examples.
Kapitalertragssteuern in zeitstetigen Finanzmarktmodellen
Wednesday, 19.3.14, 09:00-10:00, Raum 404, Eckerstr. 1
The Skorokhod embedding problem for homogeneous diffusions and applications to stopping contests
Wednesday, 19.3.14, 11:00-12:00, Raum 404, Eckerstr. 1
A probalistic link between stochastic processes, multivariate distributions an portfolio-credit derivatives
Wednesday, 19.3.14, 14:00-15:00, Raum 404, Eckerstr. 1
Kreditrisiken: Modell, Risiken und neue Entwicklungen
Thursday, 20.3.14, 09:00-10:00, Raum 404, Eckerstr. 1
Stochastische Volatilität und mögliche Langzeitabhängigkeit: Das supOU Modell
Thursday, 20.3.14, 11:00-12:00, Raum 404, Eckerstr. 1
Parameterunsicherheit in der Portfoliooptimierung
Thursday, 20.3.14, 15:00-16:00, Raum 404, Eckerstr. 1
Tates Residuo, transposed to the K-theory spektrum
Thursday, 27.3.14, 10:15-11:15, Raum 127, Eckerstr. 1
Ich werde eine hübsche Idee von John Tate zum klassischen Residuum auf Kurven aufgreifen. Arbarello, deConcini und Kac haben darauf aufbauend einen klassischen Reziprozitätssatz von Weil für K_2 Gruppen auf Kurven bewiesen. Wir dehnen diese Idee auf das volle K-Theoriespektrum sowie höhere Dimension aus, und noch weiter. Insbesondere erhält man diese klassischen Resultate als Spezialfälle wieder".\n(gem. mit Michael Gröchenig, Imperial UK und Jesse Wolfson, Northwestern US)