uk: Математика, природничі науки

uk: вхід без авторизації

name: Finding and breaking Lie symmetries: implications for structural identifiability and observability of dynamic models


Remi Jaoui

type: Person

cs: Matematika

de: Mathematik

fi: matematiikka

uk: Математика

en: Mathematics

fr: Mathématiques

da: Matematik

es: Matemáticas

nl: Wiskunde

de: Mathematik, Naturwissenschaften

uk: Математика, природничі науки

en: Mathematics, Natural Sciences

TIB AV-Portal

type: Service

type: WebContent

type: MediaObject

@language: en

cs: přihlášení není vyžadováno

de: keine Anmeldung erforderlich

uk: вхід без авторизації

en: no login required

nl: geen login vereist

name: A model-theoretic analysis of geodesic equations in negative curvature

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery

type: Organization

cs: Video

de: Video

fi: Video

uk: Відео

en: Video

fr: Vidéo

da: Video

nl: Video

es: Video


uk: Математика, природничі науки

uk: вхід без авторизації

name: Organization Scanlon, Thomas (Moderation)

name: Introduction to tropical algebraic geometry


Irreducibility and generic ODEs

uk: Математика, природничі науки

uk: вхід без авторизації


cs: Informatika

de: Informatik

fi: tietojenkäsittelytiede

uk: Комп'ютерні науки

en: Computer Science

fr: Informatique

da: Datalogi

es: Ciencias de la Computación

nl: Informatica

cs: Technické vědy

de: Ingenieurwissenschaften

fi: tekniikka

uk: Інженерія

en: Engineering Sciences

fr: Ingénierie

da: Ingeniørvidenskab

es: Ingeniería

nl: Engineering

description: Topics: * Create a new project for Volto and Plone * Developing and testing locally * Using a CI to create images for deploy * Web server configuration

uk: вхід без авторизації

name: Volto and Plone Deployments Training: Learn how to deploy new sites with Volto UI and Plone


uk: Математика, природничі науки

uk: вхід без авторизації

name: Ask not what algebra can do for biology - ask what biology can do for algebra


uk: Математика, природничі науки

uk: вхід без авторизації

name: Spreading speeds of nonlocal diffusion KPP equations


uk: Математика, природничі науки

uk: вхід без авторизації

name: Organization Matano, Hiroshi (Moderation)

name: Sharp discontinuous traveling waves in a hyperbolic Keller–Segel equation


uk: Математика, природничі науки

uk: вхід без авторизації

name: Propagating terraces in multidimensional and spatially periodic domains


uk: Математика, природничі науки

uk: вхід без авторизації

name: Asymptotic behavior of solutions to level-set mean curvature flow equations with discontinuous source terms


uk: Математика, природничі науки

uk: вхід без авторизації

name: The symmetry of stable solutions of semilinear elliptic equations


uk: Математика, природничі науки

uk: вхід без авторизації

name: Reaction-diffusion equations in the half-space


uk: Математика, природничі науки

uk: вхід без авторизації

name: Mathematical analysis of a reaction-diffusion model for Neolithic transition in Europe


uk: Математика, природничі науки

uk: вхід без авторизації

name: Wave propagation in two-species strong competition models


uk: Комп'ютерні науки

description: Migrating a site is always a challenging task, but when you have dozens of subsites with specific brand standards and custom user functionality, the challenge becomes mammoth. Six Feet Up worked hand-in-hand with Purdue’s College of Engineering to migrate their existing Zope site and its subsites into a new Plone instance running on Plone 5.2 / Python 3. Throughout the migration process, we considered the project scale, timelines, and limiting the impact on end users — all while managing the balance between user needs and best practices. During this presentation, you will learn: - why it matters to think user-first during migration, - about creative solutions for translating content and functionality into Plone, and - how to successfully migrate subsites.

uk: вхід без авторизації

name: From Zope to Plone: Thinking User-First During Migration


uk: Математика, природничі науки

uk: вхід без авторизації

name: Organization Ninomiya, Hirokazu (Moderation)

name: Convergence to traveling wave for the logarithmic diffusion equation with reaction term


uk: Математика, природничі науки

uk: вхід без авторизації

name: The principal eigenvalue problem for some second order elliptic and parabolic operators with large advection

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery


uk: Комп'ютерні науки

uk: вхід без авторизації

name: Plone Conference 2021 - Guillotina React Training


uk: Математика, природничі науки

uk: вхід без авторизації

name: Strong competition limit, traveling waves and best dispersal strategy for Lotka-Volterra competitive systems


uk: Математика, природничі науки

uk: вхід без авторизації

name: Effect of Phosphorylation and Mutation to Asp and Glu on the Conformational Landscape of an Intrinsically Disordered Region


uk: Математика, природничі науки

uk: вхід без авторизації

name: The importance of correlations in biology: Using Huge Data in the Context of Protein Structures


uk: Математика, природничі науки

uk: вхід без авторизації

name: Chemical shifts based structural ensemble generation for intrinsically disordered proteins: A case study


uk: Математика, природничі науки

uk: вхід без авторизації

name: SimRNA: a coarse-grained method for RNA 3D structure modeling - new ideas accounting for on non-canonical base pairing


uk: Математика, природничі науки

uk: вхід без авторизації

name: Structure prediction of mono- and oligomeric tarets using the physics-based coarse-grained UNRES force field and information from databases – CASP13/CAPRI46


uk: Математика, природничі науки

uk: вхід без авторизації

name: Pruning false positives cases from small molecule docking results using machine learning techniques


uk: Математика, природничі науки

uk: вхід без авторизації

name: Limits of performance for protein side chain packers


uk: Математика, природничі науки

uk: вхід без авторизації

name: A Global Subspace Optimization Algorithm for Minimum Energy Molecular Cluster Conformation


uk: Математика, природничі науки

uk: вхід без авторизації

name: Computational model of kinetochore-microtubule attachments


Graph Theory in Orthology Detection

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Quantum resonance theory of open system dynamics


uk: Математика, природничі науки

uk: вхід без авторизації

name: Nonlinear Quantum Adiabatic Approximation


uk: Математика, природничі науки

uk: вхід без авторизації

name: Energetic footprints of coherence and irreversibility in the quantum regime


uk: Математика, природничі науки

uk: вхід без авторизації

name: Classical emulation of quantum-coherent thermal machines


uk: Математика, природничі науки

uk: вхід без авторизації

name: The quantum Carnot engine and its quantum signature


uk: Математика, природничі науки

uk: вхід без авторизації

name: Coherence in Light-harvesting Energy Transfer

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery


uk: Математика, природничі науки

uk: вхід без авторизації

name: Transfer tensor method: efficient simulation of open quantum systems


uk: Математика, природничі науки

uk: вхід без авторизації

name: Quantum non-Markovianity: A physicist's perspective


uk: Математика, природничі науки

uk: вхід без авторизації

name: Microscopically-derived modelling of quantum networks subject to multiple environments


uk: Математика, природничі науки

uk: вхід без авторизації

name: Environmental non-additivity and strong-coupling in non-equilibrium quantum systems


uk: Математика, природничі науки

uk: вхід без авторизації

name: Mixed quantum-classical simulations of nonequilibrium heat transport in molecular junctions


Quantum time-dependent temperature

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Exceptional points of the Liuovillian dynamics


uk: Математика, природничі науки

uk: вхід без авторизації

name: Thermodynamics of strongly coupled driven quantum systems


uk: Математика, природничі науки

uk: вхід без авторизації

name: Bayesian optimization for inverse problems in quantum dynamics


uk: Математика, природничі науки

uk: вхід без авторизації

name: Macroscopic coherence as an emergent property in molecular nanotubes


uk: Математика, природничі науки

uk: вхід без авторизації

name: Autonomous entanglement engines: open questions raised by the use of the reset master equation


uk: Математика, природничі науки

uk: вхід без авторизації

name: Macroscopic Long-Range Dynamics of Fermions and Quantum Spins on the Lattice


uk: Математика, природничі науки

uk: вхід без авторизації

name: Is the dynamics of biomolecular excitons quantum coherent?


uk: Математика, природничі науки

uk: вхід без авторизації

name: First Principles Model Hamiltonian Ensembles for Light Harvesting: Modeling Dissipative Down Conversion - Signatures of Vibronic Energy Transfer in Nonlinear 2DES Signals - CSDM+PLDM


Nonadiabatic Charge and Energy Transfer

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: The Steady State Induced by Natural Incoherent Light: Rates, Dynamics and Coherences


uk: Математика, природничі науки

uk: вхід без авторизації

name: Charge and energy transfer dynamics in condensed phase using the non-perturbative hierarchical equations of motion approach


uk: Математика, природничі науки

uk: вхід без авторизації

name: Full counting statistics of charge and energy transport (applications, methods, measurements)


uk: Математика, природничі науки

uk: вхід без авторизації

name: Stochastic Formalism and Simulation of Quantum Dissipative Dynamics

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery


uk: Математика, природничі науки

uk: вхід без авторизації

name: On a hypersimplicial Van Kampen-Flores theorem


uk: Математика, природничі науки

uk: вхід без авторизації

name: Data Classification Algorithms and Tverberg-type theorems


uk: Математика, природничі науки

uk: вхід без авторизації

name: On a scissors congruence phenomenon for some polytopes


Intersection patterns in good covers

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Helly numbers for crystals and cut-and-project sets


uk: Математика, природничі науки

uk: вхід без авторизації

name: Colorful Helly-type Theorems for Ellipsoids


On F-convexity and related problems

uk: Математика, природничі науки

uk: вхід без авторизації


Are we afraid of Projective Geometry?

uk: Математика, природничі науки

uk: вхід без авторизації


Exact quantitative Helly theorems.

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: The geometry and combinatorics of discrete line segment hypergraphs.


Colorful and Fractional Helly theorems

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Properties of closure operators in the plane


uk: Математика, природничі науки

uk: вхід без авторизації

name: Geometric intersection patterns and order


uk: Математика, природничі науки

uk: вхід без авторизації

name: Borsuk--Ulam type theorem for f--neighbors


uk: Математика, природничі науки

uk: вхід без авторизації

name: Embeddings of k-complexes into 2k-manifolds


uk: Математика, природничі науки

uk: вхід без авторизації

name: Characterizations of the sphere by means of visual cones: an alternative proof of Matsuura's theorem


On the isometric Banach conjecture

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Envy-free division using mapping degree.


uk: Математика, природничі науки

uk: вхід без авторизації

name: Bistellar and Edge Flip Graphs of Triangulations in the Plane - Geometry and Connectivity.


uk: Математика, природничі науки

uk: вхід без авторизації

name: Theorems of Helly and Tverberg without dimension


keywords:
Wissenschaftsmanagement
Hochschulmanagement
Strategisches Management
strategic Management
form follows function
formula funding
strategic fund
top-down
bottom-up
Management of Higher Education
strategic university management

de: Rechts-, Wirtschafts- und Sozialwissenschaften

uk: Право, економіка та суспільні науки

en: Law, Economics and Social Sciences

de: Wirtschaftswissenschaften

uk: Бізнес та економіка

en: Business and Economics

description: In this video, Professor Ziegele explains the basics of strategic management for universities. Strategic management can bring tremendous benefits to universities and faculties. But university and faculty strategies need a good story and priority. A good mix of top-down and bottom-up strategies should always be developed. The biggest difficulty in universities is often to implement the developed strategy. These difficulties can be countered by developing good tools to implement the strategy.

uk: вхід без авторизації

name: Strategic Management in Higher Education Institutions: Experiences and 5 Basic Lessons Learned

Hochschule Osnabrück

addressCountry: DE

addressLocality: Osnabrück

addressRegion: Lower Saxony


Thermit-Versuch

keywords:
fachfremd Unterrichten
Chemie
Experiment
Redoxreaktion
Aluminium
Eisen
Schweißen
Metalle
Demonstrationsexperiment
chemische Reaktion

de: Chemie

fi: kemia

uk: Хімія

en: Chemistry

fr: Chimie

da: Kemi

es: Química

nl: Scheikunde

uk: Математика, природничі науки

@language: de

uk: вхід без авторизації

Europa-Universität Flensburg (EUF)

addressLocality: Flensburg

addressRegion: Schleswig-Holstein

name: Institut für mathematische, naturwissenschaftliche und technische Bildung


keywords:
fachfremd Unterrichten
Chemie
Experiment
Redoxreaktion
Metalle
Nichtmetalle
Kupfer
Wasserstoff
chemische Reaktion
Demonstrationsexperiment

uk: Математика, природничі науки

uk: вхід без авторизації

name: Reduktion von Kupferoxid mit Wasserstoff


keywords:
fachfremd Unterrichten
Chemie
Redoxreaktion
digitale Medien
Wasserstoff
Seifenblasen
Zeitlupe
Slow-Motion
Kerze
Gasflasche
chemische Reaktion
Demonstrationsexperiment
Schüler:innenversuch

uk: Математика, природничі науки

uk: вхід без авторизації

name: Der Kerzensprung und Wasserstoff-Seifenblasen: Slow-Motion-Aufnahmen von Experimenten mit der Zeitraffer-Funktion des Smartphones


keywords:
fachfremd Unterrichten
Glarohr
Laborglas
Glas schneiden
Glasbearbeitung

uk: Математика, природничі науки

uk: вхід без авторизації

name: Glasbearbeitung: Schneiden, Rundschmelzen und Biegen von Glasrohren für den Unterricht


keywords:
fachfremd Unterrichten
Chemie
Elektrochemie
Redoxreaktion
Elektroden

uk: Математика, природничі науки

uk: вхід без авторизації

name: Kohleelektroden - welche eignet sich wann?: Kohleelektroden nach Oetken selbst bauen


Natrium auf Wasser

keywords:
fachfremd Unterrichten
Chemie
Metalle
Natrium
Wasserstoff
Wasser
Indikator
Demonstrationsexperiment
Redoxreaktion
Säure-Base-Reaktion

uk: Математика, природничі науки

uk: вхід без авторизації


Knallgasprobe: Nachweis von Wasserstoff

keywords:
fachfremd Unterrichten
Experiment
Redoxreaktion
Nachweisreaktion
Wasserstoff
Sauerstoff
Knallgas
Wasser

uk: Математика, природничі науки

uk: вхід без авторизації


Verdünnungsreihe mit Salzsäure

keywords:
fachfremd Unterrichten
Chemie
Experiment
Säure-Base-Reaktion
pH-Wert
Salzsäure
Indikator
Rotkohl
chemische Reaktion
Verdünnung
Schüler:innenversuch

uk: Математика, природничі науки

uk: вхід без авторизації


keywords:
fachfremd Unterrichten
Chemie
Experiment
Halogene
Chlor
Redoxreaktion
chemische Reaktion
Demonstrationsexperiment

uk: Математика, природничі науки

uk: вхід без авторизації

name: Herstellung von Chlor - richtig und sicher gestalten


keywords:
fachfremd Unterrichten
Chemie
Lösungen
Mol
molare Masse
Konzentration

uk: Математика, природничі науки

uk: вхід без авторизації

name: Ansetzen von Lösungen im Labor: Mol, molare Masse, Umrechnen von % in Mol, Massen- und Gewichtsprozent


keywords:
fachfremd Unterrichten
Chemie
Experiment
Elektrochemie
galvanisches Element
Daniellelement
Redoxreaktion
Spannung
Stromstärke
Schüler:innenversuch

uk: Математика, природничі науки

uk: вхід без авторизації

name: Daniell-Element: Stromkreis richtig stecken, Spannung und Stromstärke messen


HCl-Springbrunnen

keywords:
fachfremd Unterrichten
Chemie
Experiment
Säure-Base-Reaktion
Chlorwasserstoff
Salzsäure
Löslichkeit
Gase
chemische Reaktion
Demonstrationsexperiment

uk: Математика, природничі науки

uk: вхід без авторизації


keywords:
fachfremd Unterrichten
Chemie
Experiment
Säure-Base-Reaktion
Chlorwasserstoff
Salzsäure
Löslichkeit
Gase
chemische Reaktion
Demonstrationsexperiment
Schüler:innenversuch

uk: Математика, природничі науки

uk: вхід без авторизації

name: HCl-Springbrunnen in klein: - eine unkomplizierte Alternative zum großen Springbrunnenversuch


keywords:
fachfremd Unterrichten
Chemie
Experiment
Säure-Base-Reaktion
Ammoniak
Löslichkeit
Gase
chemische Reaktion
Demonstrationsexperiment
Schüler:innenversuch

uk: Математика, природничі науки

uk: вхід без авторизації

name: Ammoniak-Springbrunnen in klein: Eine unkomplizierte Alternative zum großen Springbrunnenversuch


uk: Комп'ютерні науки

uk: Бібліотекознавство, документознавство

en: Information and Library Sciences

de: Geisteswissenschaften

uk: Гуманітарні науки

en: Humanities

uk: вхід без авторизації

name: Al and Science Communication: Al and Machine Learning innovations for accelerating science, technology, and medicine

name: International Council for Scientific and Technical Information (ICSTI)


uk: Комп'ютерні науки

uk: Бібліотекознавство, документознавство

uk: Гуманітарні науки

uk: вхід без авторизації

name: Al-aided Diagnosis and Deep Learning Imaging in Medicine


uk: Комп'ютерні науки

uk: Бібліотекознавство, документознавство

uk: Гуманітарні науки

uk: вхід без авторизації

name: Semantic Scholar: Al-driven platform for scientific discovery


uk: Комп'ютерні науки

uk: Бібліотекознавство, документознавство

uk: Гуманітарні науки

uk: вхід без авторизації

name: OCR-D: Von Prototypen zu Digitaliserungsprojekten

name: Verein Deutscher Bibliothekarinnen und Bibliothekare e. V. (VDB)

name: Berufsverband Information Bibliothek e. V. (BIB)


Enterprise Knowledge Graphs

uk: Комп'ютерні науки

uk: Бібліотекознавство, документознавство

uk: Гуманітарні науки

uk: вхід без авторизації


uk: Комп'ютерні науки

uk: Бібліотекознавство, документознавство

uk: Гуманітарні науки

uk: вхід без авторизації

name: From Papers to Knowledge: Representing Scholarly Contributions in the Open Research Knowledge Graph (ORKG)


uk: Комп'ютерні науки

uk: Бібліотекознавство, документознавство

uk: Гуманітарні науки

description: Die Open-Source-Software OpenRefine ist bekannt für ihre grafische Oberfläche, die einem Tabellenverarbeitungsprogramm ähnelt. Sie wird oft als Desktop-Software installiert und zur Analyse, Bereinigung und Anreicherung von Metadaten eingesetzt. Laut Nutzerstudie von 2020 [1] sind Bibliothekar*innen mit rund 38% die größte Nutzergruppe. Weniger bekannt sind die Automatisierungsmöglichkeiten von OpenRefine. Durch die Client-Server-Architektur lässt sich OpenRefine auch auf einem Webserver installieren und über die Kommandozeile steuern. Das hat den Charme, dass Transformationsregeln in der Oberfläche spielerisch erprobt werden können und dann beispielsweise täglich automatisiert auf neue Datenlieferungen angewendet werden können. Die Automatisierungsmöglichkeiten werden am Beispiel der Open-Source-Software openrefine-client [2] demonstriert. Der Hauptbestandteil des Vortrags ist eine Live-Präsentation, die bei Interesse auch zeitgleich selbst nachvollzogen werden kann. Dafür werden über openrefineder [3] On-Demand-Server mit Jupyter Notebooks bereitgestellt, die ohne Installation im Browser aufgerufen werden können.

uk: вхід без авторизації

name: Automatisierungsmöglichkeiten der Software OpenRefine


keywords:
OER
Open Educational Resources
Tutorial
Video
twillo

uk: Комп'ютерні науки

uk: Бібліотекознавство, документознавство

uk: Гуманітарні науки

uk: вхід без авторизації

name: TutOERials: Grundlagen offener Medienproduktion


Kalkwasserprobe

keywords:
fachfremd Unterrichten
Chemie
Experiment
Nachweisreaktion
Fällungsreaktion
Kohlenstoffdioxid

uk: Математика, природничі науки

uk: вхід без авторизації

name: Institut für mathematische, naturwissenschaftliche und technische Bildung


Natriumchlorid-Synthese

keywords:
fachfremd Unterrichten
Chemie
Experiment
Halogene
Chlor
Redoxreaktion
chemische Reaktion
Natrium
Metalle
Salze
Nichtmetalle
Demonstrationsexperiment

uk: Математика, природничі науки

uk: вхід без авторизації


Umgang mit Natrium

keywords:
fachfremd Unterrichten
Chemie
Natrium
Metalle

uk: Математика, природничі науки

uk: вхід без авторизації


Wachs-Flammenwerfer

keywords:
fachfremd Unterrichten
Chemie
Experiment
Explosion
Wasserstoff
Wachs
Demonstrationsexperiment
exotherm
Kerze
chemische Reaktion

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Ordered graphs and hypergraphs: new results and open problems

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery


uk: Математика, природничі науки

uk: вхід без авторизації

name: Super-pancyclic hypergraphs and bipartite graphs


Equiangular lines with a fixed angle

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: On the size of subsets of F_p^n without p distinct elements summing to zero


uk: Математика, природничі науки

uk: вхід без авторизації

name: Non-constructive absorbers and applications


Traces of Hypergraphs

uk: Математика, природничі науки

uk: вхід без авторизації


Minimum saturated families

uk: Математика, природничі науки

uk: вхід без авторизації


Halfway to Rota’s basis conjecture

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: An algebraic inverse theorem for the quadratic Littlewood–Offord problem


Covering cubes by hyperplanes

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Nearly-linear increasing paths in edge-ordered graphs


Disproportionate division

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Improved bounds for the Brown-Erdos-Sos problem


Completion and deficiency problems

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Combinatorial questions in optimal transport


Expander graphs both local and global

uk: Математика, природничі науки

uk: вхід без авторизації


How redundant is Mantel’s Theorem?

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Extremal problems concerning cycles in tournaments


uk: Математика, природничі науки

description: Although absence of the local order parameters is a fundamental feature of the topological phases, the Berry connection that represents a quantum interference of many body states successfully characterizes the bulk of the topological phases. The Chern number for the bulk of the quantum Hall states is a typical example. Also, with boundaries, appearance of local modes as the edge states characterizes the phase as the bulk-edge correspondence. As for the short range entangled state, the Berry phase that is quantized due to symmetry is used as a “quantum” local order parameter of the bulk. Z_2 Berry phase for the Haldane phase of the spin 1 quantum spin chain is a typical example. Here again, with boundaries, low energy local modes as the edge states appear associated with the nontrivial Berry phases as the bulk-edge correspondence. Focusing on the systems with interaction, we demonstrate the use of the symmetry protected Berry phases and the bulk-edge correspondence for various examples such as the generic valence bond solid (VBS) states and the corner states of the higher order topological phases.

uk: вхід без авторизації

name: Symmetry protected Berry phases and edge states with interaction


uk: Математика, природничі науки

description: A Delone set is a uniformly discrete and relatively dense subset of Euclidean space \mathbb{R}^{d}. As such they constitute a mathematical model for a general solid material. By choosing an abstract transversal for the translation action on the orbit space of the Delone set, one obtains an etale groupoid. In the absence of a \mathbb{Z}^d-labelling, the associated groupoid C*-algebra replaces the crossed product algebra as the natural algebra of observables. The K-theory of the groupoid C*-algebra is a natural home for the formulation of the bulk-boundary correspondence for topological insulators as well as a source for numerical invariants of (weak) topological phases. This is joint work with Chris Bourne

uk: вхід без авторизації

name: Index theory and topological phases of aperiodic lattices


uk: Математика, природничі науки

description: Every (2+1) dimensional quantum many-body system with an energy gap is believed to be described by a topological quantum field theory (TQFT) in the low energy limit. What this means concretely is that every many-body system of this kind is associated with a collection of universal topological data. Some of this data, however, is missing a precise definition that would allow for its computation from a microscopic Hamiltonian. In this talk, I will address this issue by giving a microscopic definition of the “F-symbol” --- one of the most poorly understood pieces of data that characterize TQFTs. I will also discuss applications of this definition to the computation of anomalies at the boundaries of (2+1) dimensional symmetry-protected topological phases.

uk: вхід без авторизації

name: Bridging the gap between lattice models and TQFTs


uk: Математика, природничі науки

description: "Flux attachment” to form composite particles gives rise to an emergent geometry in the fractional quantum Hall effect. I will describe how the composite boson and composite fermion pictures complement each other as respective analogs of the unit cell and mobile charge carriers in crystalline electronic matter.

uk: вхід без авторизації

name: Geometry of Flux Attachment in the Fractional Quantum Hall Effect


uk: Математика, природничі науки

description: Kitaev's quantum double models provide a rich class of examples of two-dimensional lattice systems with topological order in the ground states and a spectrum described by anyonic elementary excitations. The infinite volume ground states of the abelian quantum double models come in a number of equivalence classes called superselection sectors. We prove that the superselection structure remains unchanged under uniformly small perturbations of the Hamiltonians. We introduce a Dynamical Toric Code Model and discuss some of its features.

uk: вхід без авторизації

name: A Dynamical Toric Code model and Stability of the superselection sectors of two-dimensional quantum lattice models


Fractional quantum transport

uk: Математика, природничі науки

description: I will present an index associated to a local unitary and a projection in the setting of many-body interacting particles on a lattice. Its values are in general rational, being integer multiples of the inverse of the rank of the projection.

uk: вхід без авторизації


uk: Математика, природничі науки

description: As an application of the many-body index (see Sven Bachmann's talk), the Avron-Dana-Zak relation is shown to hold in the context of interacting quantum lattice systems, for the integer and fractional quantum Hall effects. A key formal property used to obtain this result is the additivity of the many-body index.

uk: вхід без авторизації

name: Hall conductance and Avron-Dana-Zak relation for interacting systems


uk: Математика, природничі науки

description: For systems where periodic boundary conditions are not an option, the spectral localizer is a tool that can separate edge and bulk effects. This is the tool introduced by Kisil in defining the Clifford spectrum. The localizer can been thought of as an augmented Hamiltonian modeling a finite system and a probe, which picks up the symmetries from the underlying system. In all ten symmetry classes and all dimensions, one can use the localizer to create a K-theory class in either the Trout or Van Daele pictures of K-theory that is expected to correspond to a bulk invariant. As new methods for computing the boundary maps in K-theory are discovered, more and more instances of the index can be rigorously proven to equal a bulk invariant. Specific applications discussed will include numerical studies (by various investigators) of nanowires in class BDI and a Chern insulators built on the vertices of an aperiodic tiling of the plane.

uk: вхід без авторизації

name: The spectral localizer for estimating bulk gaps and calculating K-theory


Coarse geometry and topological phases

uk: Математика, природничі науки

description: We propose the Roe C*-algebra from coarse geometry as a model for topological phases of disordered materials. We explain the robustness of this C*-algebra and formulate the bulk-edge correspondence in this framework. We describe the map from the K-theory of the group C*-algebra of Z^d to the K-theory of the Roe C*-algebra, both for real and complex K-theory. (Article with Elke Ewert)

uk: вхід без авторизації


uk: Математика, природничі науки

description: It is known that a momentum space Chern class obstructs existence of good tight-binding models in position space. This is a T-duality, and holds in more general geometric contexts, e.g. crystallographic, defective, and non-Euclidean effective interacting topological phases. Namely, good Wannier bases correspond to free modules over pre-C*-algebras of the symmetry group. Thus K-theory and T-duality give precise tools to find topological insulators and understand their boundary gapless modes; explicit new examples will be given. Joint with M. Ludewig.

uk: вхід без авторизації

name: (Non)-existent atomic limits: geometric meaning of K-theory in the solid-state


uk: Математика, природничі науки

description: In the context of quantum spin liquids, it is long known that the condensation of fractionalized excitations can inevitably break certain physical symmetries. For example, condensing spinons will usually break spin rotation and time reversal symmetries. We generalize these phenomena to the context of a generic continuous quantum phase transition between symmetry enriched topological orders, driven by anyon condensation. We provide two rules to determine whether a symmetry is enforced to break across an anyon condensation transition or not. Using a dimensional reduction scheme, we establish a mapping between these symmetry-breaking anyon-condensation transitions in two spatial dimensions, and deconfined quantum criticality in one spatial dimension.

uk: вхід без авторизації

name: Spontaneous symmetry breaking from anyon condensation

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery


uk: Математика, природничі науки

description: As realized by TKNN in 1982, a relevant Transport-Topology Correspondence holds true for gapped periodic 2D systems, in the sense that a non-vanishing Hall conductivity corresponds to a non-trivial topology of the space of occupied states, decomposed with respect to the crystal momentum (the Bloch bundle). More recently, a related Localization-Topology Correspondence has been noticed and mathematically proved for 2D and 3D gapped periodic quantum system. The result states that the Bloch bundle is (Chern) trivial if and only if there exists a system of composite Wannier functions on which the expectation value of the squared position operator is finite. In other words, whenever the system is in a Chern-non-trivial phase, the composite Wannier functions are very delocalized, while in the Chern trivial phase they can be chosen exponentially localized (joint work with D. Monaco, A. Pisante and S. Teufel). During my talk, I will report on this result and the essential ideas of its proof, as well as on the ongoing attempt to generalize this correspondence to non-periodic gapped quantum systems (work in progress with G. Marcelli and M. Moscolari).

uk: вхід без авторизації

name: The Localization-Topology Correspondence: periodic systems and beyond


uk: Математика, природничі науки

description: Guided by the many-particle quantum theory of interacting systems, we develop a uniform classification scheme for topological phases of disordered gapped free fermions, encompassing all symmetry classes of the Tenfold Way. We apply this scheme to give a mathematically rigorous proof of bulk-boundary correspondence. To that end, we construct real C^\ast-algebras harbouring the bulk and boundary data of disordered free-fermion ground states. These we connect by a natural bulk-to-boundary short exact sequence, realising the bulk system as a quotient of the half-space theory modulo boundary contributions. To every ground state, we attach two classes in different pictures of real operator K-theory (or KR-theory): a bulk class, using Van Daele's picture, along with a boundary class in Kasparov's Fredholm picture. We then show that the connecting map for the bulk-to-boundary sequence maps these KR-theory classes to each other.

uk: вхід без авторизації

name: Bulk-boundary correspondence for disordered free-fermion topological phases


uk: Математика, природничі науки

description: With the possibility to manufacture almost any structure which might exhibit topological phenomena and to control its boundary there is a need to generalise the standard approach to the bulk boundary correspondence which is based on crossed products to more general settings. For the bulk algebra this can be done using the pattern groupoid algebra. What we will focus on is an approach which allows to include boundaries and to construct more flexible half space algebras than in the cases considered so far. Applications to topological pumping will be given.

uk: вхід без авторизації

name: Bulk boundary correspondance for quasiperiodic chains


Affine actions with Hitchin linear part

uk: Математика, природничі науки

description: Properly discontinuous actions of a surface group on Rd by affine transformations were shown to exist by Danciger-Gueritaud-Kassel. We show, however, that if the linear part of an affine surface group action is in the Hitchin component, then the affine action is not properly discontinuous. The key case is that of linear part in SO(n, n − 1), so that Rd = Rn,n−1 is the model for flat pseudo-Riemannian geometry of signature (n, n−1). Here, the translational parts determine a deformation of the linear part into SO(n, n) Hitchin representations and the crucial step is to show that such representations are not Anosov in SL(2n, R) with respect to the stabilizer of an n-plane. Joint with Tengren Zhang.

uk: вхід без авторизації


uk: Математика, природничі науки

description: In this talk we describe non-trivial sufficient conditions on a diverging sequence of Hitchin representations so that its limit in the Parreau boundary can be described as an action on a tree. These non-trivial conditions are given in terms of Fock-Goncharov coordinates on moduli spaces of positive tuples of flags.

uk: вхід без авторизації

name: Sequences of Hitchin representations of Tree-Type


uk: Математика, природничі науки

description: Given a hyperbolic 3-manifold with cusps, we consider the composition of a lift of its holonomy in SL(2, C) with the irreducible representation in SL(n, C), that yields a twisted Alexander polynomial An(t), for each natural n. We prove that, for a complex number z with norm one log |An(z)|/n2 converges to the hyperbolic volume of the manifold divided by 4π, as n → ∞. This generalizes and uses a theorem of W. Mueller for closed manifolds on analytic torsion. This is joint work with L. Bénard, J. Dubois and M. Heusener.

uk: вхід без авторизації

name: Twisted Alexander polynomials and hyperbolic volume for three-manifolds


uk: Математика, природничі науки

description: In this talk we will discuss quasi-Hitchin representations in Sp(4, C), which are deformations of Fuchsian (and Hitchin) representations which remain Anosov. These representations acts on the space Lag(C4) of complex lagrangian grassmanian subspaces of C4. This theory generalises the classical and important theory of quasi-Fuchsian representations and their action on the Riemann sphere CP 1 = Lag(C2). In the talk, after reviewing the classical theory, we will define Anosov and quasi-Hitchin representations and we will discuss their geometry. In particular, we show that the quotient of the domain of discontinuity for this action is a fiber bundle over the surface and we will describe the fiber. The projection map comes from an interesting parametrization of Lag(C4) as the space of regular ideal hyperbolic tetrahedra and their degenerations. (This is joint work with D. Alessandrini and A. Wienhard.)

uk: вхід без авторизації

name: The geometry of quasi-Hitchin symplectic Anosov representations


uk: Математика, природничі науки

description: Anosov representations are representations of a hyperbolic group to a non-compact semisimple Lie group that are “geometrically well-behaved”. In the case when the target Lie group is PGL(d, R), these representations admit a limit set in d − 1 dimensional projective space that is homeomorphic to the boundary of the group. Under some irreducibility conditions, we give necessary and sufficient conditions for when this limit set is a C1,a sub manifold. This is joint work with A. Zimmer.

uk: вхід без авторизації

name: Regularity of limit curves of Anosov representations


uk: Математика, природничі науки

description: Anosov representations of word hyperbolic groups form a rich class of discrete subgroups of semisimple Lie groups, generalizing classical convex cocompact groups of real rank one Lie groups. A large class of projective Anosov representations are Benoist representations. In this talk, we are going to give a characterization of Benoist representations in terms of the existence of limit maps. This is joint work with Richard Canary.

uk: вхід без авторизації

name: Characterizing Benoist representations by limit maps


uk: Математика, природничі науки

uk: вхід без авторизації

name: Eigenvalue rigidity for Zariski-dense subgroups


uk: Математика, природничі науки

description: Mutations of quivers were introduced by Fomin and Zelevinsky in the beginning of 2000’s in the context of cluster algebras. Since then, mutations appear (sometimes completely unexpectedly) in various domains of mathematics and physics. Using mutations of quivers, Barot and Marsh constructed a series of presentations of finite Coxeter groups as quotients of infinite Coxeter groups. We will discuss a generalization of this construction leading to a new invariant of bordered marked surfaces, and a geometric interpretation: it occurs that presentations constructed by Barot and Marsh give rise to a construction of geometric manifolds with large symmetry groups, in particular to some hyperbolic manifolds of small volume with proper actions of Coxeter groups. This work is joint with Pavel Tumarkin.

uk: вхід без авторизації

name: Coxeter groups, quiver mutations and hyperbolic manifolds


uk: Математика, природничі науки

description: We will try to show that closed manifolds of negative curvature do not admit complete special affine structures whose linear parts are partially hyperbolic in the dynamical sense. Furthermore, they cannot admit complete affine structures with semi-simple P-Anosov linear holonomy groups. Finally, we will present an attempt to show that closed affine manifolds cannot have partially hyperbolic linear holonomy.

uk: вхід без авторизації

name: Closed affine manifolds with partially hyperbolic linear holonomy


uk: Математика, природничі науки

description: I will discuss several results on abstract homomorphisms between the groups of rational points of algebraic groups. The main focus will be on a conjecture of Borel and Tits formulated in their landmark 1973 paper. Our results settle this conjecture in several cases; the proofs make use of the notion of an algebraic ring. I will mention several applications to character varieties of finitely generated groups and representations of some non-arithmetic groups.

uk: вхід без авторизації

name: Abstract homomorphisms of algebraic groups and applications


uk: Математика, природничі науки

description: We present recent developments in a novel domain of computational group theory: computing with infinite linear groups. Special consideration is given to algorithms for Zariski dense subgroups. This includes a computer realization of the strong approximation theorem, and algorithms for arithmetic groups. We illustrate applications of our methods to the solution of problems further afield by computer experimentation. This is joint work with Dane Flannery and Alexander Hulpke.

uk: вхід без авторизації

name: Zariski density and computing with infinite linear groups


Quantitative weak uniform discreteness

uk: Математика, природничі науки

description: I will discuss a quantitative variant of the Kazhdan-Margulis theorem generalized to probability measure preserving actions of semisimple groups over local fields. The talk is based on a joint work with Gelander and Margulis.

uk: вхід без авторизації


uk: Математика, природничі науки

description: The systole of a Riemannian manifold is the shortest length of a non-contractible closed geodesic. The purpose of this talk is to survey recent results in systole growth along congruence covers of arithmetic manifolds, and how this information interact with the geometry and the topology of the covers.

uk: вхід без авторизації

name: Systole growth on arithmetic locally symmetric spaces


Sphere packings and arithmetic

uk: Математика, природничі науки

description: We will discuss recent progress in understanding Apollonian-like sphere packings and more general objects, with connections to arithmetic hyperbolic groups, both reflective and non.

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Effective equidistribution of expanding horospheres


uk: Математика, природничі науки

description: In this talk, I will discuss some results concerning convex cocompact subgroups of the projective linear group (as defined by Danciger-Guéritaud-Kassel). These are a special class of discrete sub-groups which act convex cocompactly on a properly convex domain in real projective space. In the case when the subgroup is word hyperbolic, these are well studied objects: the inclusion representation is actually an Anosov representation. The non-hyperbolic case is less understood and will be the focus of this talk. This is joint work with Mitul Islam.

uk: вхід без авторизації

name: Convex cocompact actions of non-hyperbolic groups


uk: Математика, природничі науки

description: Let M be a Gromov–Thurston manifold. With Daniel Monclair and Jean-Marc Schlenker, we construct proper and cocompact actions of the fundamental group of M on a certain pseudo- Riemannian symmetric space. I will explain this construction, and how it relates to the existence of a globally hyperbolic anti-de Sitter manifold with Cauchy hypersurface homeomorphic to M .

uk: вхід без авторизації

name: Exotic compact quotients of pseudo-Riemannian symmetric spaces

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery


uk: Математика, природничі науки

description: Recently there has been a surge of activity in quantifying the density of values of generic quadratic forms at integer points. I will present some new and quite general results in this direction obtained via the so-called Siegel-Rogers method, which has recently been utilized by Athreya and Margulis, and later by Kelmer and Yu. This work is joint with Mishel Skenderi.

uk: вхід без авторизації

name: Khintchine-type theorems via \(L^2\) estimates for Siegel transform


uk: Математика, природничі науки

description: The ideal boundary of a negatively curved manifold naturally carries two types of measures. On the one hand, we have conditionals for equilibrium (Gibbs) states associated to Hoelder potentials; these include the Patterson-Sullivan measure and the Liouville measure. On the other hand, we have stationary measures coming from random walks on the fundamental group. We compare and contrast these two classes. First, we show that both of these of these measures can be associated to geodesic flow invariant measures on the unit tangent bundle, with respect to which closed geodesics satisfy different equidistribution properties. Second, we show that the absolute continuity between a harmonic measure and a Gibbs measure is equivalent to a relation between entropy, (generalized) drift and critical exponent, generalizing previous formulas of Guivarc’h, Ledrappier, and Blachere-Haissinsky-Mathieu. This shows that if the manifold (or more generally, a CAT(−1) quotient) is geometrically finite but not convex cocompact, stationary measures are always singular with respect to Gibbs measures. A major technical tool is a generalization of a deviation inequality due to Ancona saying the so called Green distance associated to the random walk is nearly additive along geodesics in the universal cover. Part of this is based on joint work with Gerasimov-Potyagailo-Yang and part on joint work with Tiozzo.

uk: вхід без авторизації

name: Gibbs measures vs. random walks in negative curvature


uk: Математика, природничі науки

description: Geometric finiteness is a nice property for an n-dimensional hyperbolic manifold, and one way to determine the geometric finiteness is to describe the limit set which consists of conical limit points and parabolic fixed points. On the other hand, the limit sets of geometrically infinite Kleinian groups contain infinitely many nonconical limit points. One can ask questions relating the measure-theoretic size of the limit set, conical limit set or non-conical limit set to the geometric finiteness. In this talk, we will review some existing results and conjectures about Kleinian groups with small Hausdorff dimension, and small critical exponents.

uk: вхід без авторизації

name: Hausdorff dimension and geometric finiteness in Hyperbolic spaces


Local systems and simple groups

uk: Математика, природничі науки

uk: вхід без авторизації


Exceptional Tits quadrangles

uk: Математика, природничі науки

uk: вхід без авторизації


Locally grouped spaces

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: On the relational complexity of a finite permutation group


uk: Математика, природничі науки

uk: вхід без авторизації

name: Cyclically reduced elements in Coxeter groups


Exotic fusion systems and pearls

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Geometries from inner ideals of structurable algebras


uk: Математика, природничі науки

uk: вхід без авторизації

name: Exotic fusion systems, spetses and counting conjectures


uk: Математика, природничі науки

uk: вхід без авторизації

name: Topological generation of algebraic groups


A local theory of localities

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Normalisers of primitive permutation groups


uk: Математика, природничі науки

uk: вхід без авторизації

name: Irreducible modules for pseudoreductive groups


uk: Математика, природничі науки

uk: вхід без авторизації

name: Riemann surfaces and transitive permutation groups of small fixity


uk: Математика, природничі науки

uk: вхід без авторизації

name: Classifying groups with a large subgroup, a status report


Shuffle groups

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Opposition properties and displacement of automorphisms of spherical buildings


uk: Математика, природничі науки

uk: вхід без авторизації

name: Simple fusion systems over finite p-groups with weakly closed abelian subgroup.


Rigid automorphisms of linking systems

uk: Математика, природничі науки

uk: вхід без авторизації


On Exceptional Lie Geometries

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: On rationality of blocks of finite group algebras.


uk: Комп'ютерні науки

uk: Бібліотекознавство, документознавство

uk: Гуманітарні науки

description: Many communities maintain digital knowledge bases to store and curate their communal knowledge in one place. In the biggest online community knowledge base, Wikidata and the software behind it - Wikibase - that knowledge is structured in semantic, machine-readable way by using linked open data. This presentation will showcase OpenRefine, an open source software for participation in Wikidata and Wikibase with a user-friendly interface that is still able to manipulate, enrich and upload a big amount of data at once. We will discuss a variety of use cases that are based on a data upload pipeline for 3D data enrichment in NFDI4Culture as well as a bring-your-own-data workshop from November 2021. In addition, we will demo the use of OpenRefine to transform data, match it with existing items in public knowledge bases, use the information from those items to enrich our own data, and finally contribute new information back to the community knowledge base. The core principles behind our data.

uk: вхід без авторизації

name: Developing an open source data pipeline for participation in community knowledge bases

name: Berufsverband Information Bibliothek e. V. (BIB)

Technische Informationsbibliothek (TIB)

addressLocality: Hanover


"Total Digital!" Infos und Impressionen

uk: Комп'ютерні науки

uk: Бібліотекознавство, документознавство

uk: Гуманітарні науки

uk: вхід без авторизації

name: Verein Deutscher Bibliothekarinnen und Bibliothekare e. V. (VDB)


uk: Комп'ютерні науки

uk: Бібліотекознавство, документознавство

uk: Гуманітарні науки

description: Das Ziel dieses System ist es, Nutzer*innen einen einfachen und komfortablen Zugang zu unterschiedlichen Anbietern und Diensten zu ermöglichen. Dabei wird dabei darauf geachtet, dass die dazu nötigen Mittel bereits in der IT-Infrastruktur von Bibliotheken bestehen oder sich die neuen Komponenten direkt in diese Struktur eingliedern. Ein zentraler Punkt dieses Systems ist der Schutz der persönlichen Daten. Nutzer*innen sollen immer einen Überblick haben, welche Daten ein System verwendet. Daneben sollen die Systeme von Anbietern aber auch personalisierte Dienste anbieten können. Hier wird ein dezentrales Single Sign-on Verfahren dargestellt, wie man Nutzungsrechte, z.B. zum Zugriff auf Verlagsangebote, zusammenführen kann. Diese Nutzungsrechte können dabei für eine bestimmte Kennung über verschiedene Systeme hinweg aggregiert werden. Anstatt einer zentralen, neuen, Kennung können Nutzer*innen hierbei ihre gewohnte, bereits vorhandene, Kennung ihrer Heimateinrichtung verwenden. Es wird gezeigt wie ein solches Verfahren aufgebaut werden kann: welche Software Komponenten dafür nötig sind welche Daten erhoben werden welche Daten von den Komponenten ausgetauscht werden Dieses System wurde im Rahmen des Kompetenzzentrums für Lizenzierung entwickelt.

uk: вхід без авторизації

name: Dezentrale Authentifizierung und föderale Aggregation von Nutzungsrechten


uk: Математика, природничі науки

description: A notion of laminar groups was introduced by D. Calegari. A group acting on the circle by orientation-preserving homeomorphisms is called a laminar group if it admits an invariant lamination. Abundant examples arise naturally in the study of low-dimensional topology and geometric group theory. We will discuss how topology, geometry, and dynamics interplay when we study laminar groups. Some old and new results will be discussed as examples.

uk: вхід без авторизації

name: Topology, Geometry, and Dynamics of Laminar groups

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery


uk: Математика, природничі науки

description: This talk will be an introduction to ordered groups and their connections with topology. Beginning with learning of the left-orderability of braid groups some decades ago, I will describe how I came to fall in love with the subject.

uk: вхід без авторизації

name: Ordered groups and topology — a personal journey


Ordering 3-manifold groups

uk: Математика, природничі науки

description: I will discuss practical computational techniques for proving the fundamental group of a closed hyperbolic 3-manifold is or is not orderable and describe the result of applying them to some 300,000 manifolds. I will include discussion of a new practical algorithm for solving the word problem for the fundamental group of a hyperbolic 3-manifold based on interval arithmetic and effective versions of the inverse function theorem.

uk: вхід без авторизації


ADE links and cyclic branched covers

uk: Математика, природничі науки

description: The Dynkin diagrams of types A,D and E arise in many classification problems in mathematics. We conjecture a modest addition to this list: the fibered links that induce the standard tight contact structure on S^3 and have some cyclic branched cover whose fundamental group is not left-orderable. We will discuss progress towards a proof of this conjecture. This is joint work with Michel Boileau and Steve Boyer.

uk: вхід без авторизації


uk: Математика, природничі науки

description: I will present a new characterisation for a circularly-orderable group to be left-orderable, and introduce the obstruction spectrum of a circularly-orderable group. This raises a plethora of intriguing questions. This is joint work with Jason Bell and Adam Clay.

uk: вхід без авторизації

name: Promoting circular-orderability to left-orderability


uk: Математика, природничі науки

uk: вхід без авторизації

name: Generalized torsion in 3-manifold groups and normal closures of slope elements


uk: Математика, природничі науки

description: A left-order on a group G is totally determined by its positive cone P, that is the elements in G that are greater than the identity. The set P is a subsemigroup and we can ask ourselves when this semigroup can be finitely generated, described by a regular language, etc. A recent result of S.Hermiller and Z.Sunic shows that non-abelian free groups do not have regular positive cones. I will discuss this and how to generalize this result to limit groups. The talk will be based on joint work with C.Rivas and I will report some results of my PhD student H.L.Su. (Yago Antolin is from the Unversidad Autónoma de Madrid)

uk: вхід без авторизації

name: Complexity of positive cones of limit groups, part 2


uk: Математика, природничі науки

uk: вхід без авторизації

name: Complexity of positive cones of limit groups


A work with Sang-hyun Kim

uk: Математика, природничі науки

uk: вхід без авторизації


Generalized torsion and Dehn filling

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

description: The L-space conjecture relates non-left-orderability of 3-manifold groups to Heegaard Floer homology lens-spaces, or, L-spaces. In this talk I will give the definition of an L-space , and attempt to give a feeling for this class of manifolds by focusing on some examples. One class of examples is due to Ozsváth and Szabó: branched double covers of the 3-sphere with branch set a non-split alternating link. This leads to a surprising conjecture (implied by the L-space conjecture) relating simplicity in Khovanov homology to non-left-orderability of the fundamental group of the branched double cover.

uk: вхід без авторизації

name: Khovanov homology and the L-space conjecture


uk: Математика, природничі науки

description: The L-Space Conjecture is taking the low-dimensional topology community by storm. It aims to relate seemingly distinct Floer homological, algebraic, and geometric properties of a closed 3-manifold Y. In particular, it predicts a 3-manifold Y isn't "simple" from the perspective of Heegaard-Floer homology if and only if Y admits a taut foliation. The reverse implication was proved by Ozsvath and Szabo. In this talk, we'll present a new theorem supporting the forward implication. Namely, we'll build taut foliations for manifolds obtained by surgery on positive 3-braid closures. Our theorem provides the first construction of taut foliations for every non-L-space obtained by surgery along an infinite family of hyperbolic L-space knots. As an example, we'll construct taut foliations in every non-L-space obtained by surgery along the P(-2,3,7) pretzel knot.

uk: вхід без авторизації

name: Taut Foliations, Positive 3-Braids, and the L-Space Conjecture


Modifying branched surfaces

uk: Математика, природничі науки

description: A branched surface that meets the torus boundary of a compact 3-manifold transversely (in a train track \tau) can sometimes be ``upgraded'' to a branched surface that fully carries CTFs that strongly realize all boundary slopes except one. We give a condition on \tau that guarantees that such an upgrade is possible. This approach succeeds for all alternating and Montesinos knots without L-space surgeries, for certain Murasugi sums, and for all nontrivial connected sums of alternating knots, Montesinos knots, or fibered knots. This is joint work with Charles Delman.

uk: вхід без авторизації


uk: Математика, природничі науки

description: Given a compact space endowed with a flow, every group of orbit-preserving homeomorphisms of the space naturally acts on the real line (identified with an orbit of the flow). This simple observation can be used to define interesting examples of left-orderable groups. In a joint work with Michele Triestino, we explore this idea by defining and studying a class of groups acting on suspension flows of homeomorphisms of the Cantor set. I will explain how this can be used to give a short and conceptual construction of finitely generated simple left-orderable groups, whose existence was recently obtained by Hyde and Lodha. I will also discuss several additional properties of these groups, such as the inability to act on the circle without fixed points, and the lack of subgroups with property (T).

uk: вхід без авторизації

name: Groups of piecewise linear homeomorphisms of flows


uk: Математика, природничі науки

description: This talk is motivated by the conjecture: the fundamental group of a QHS is left-orderable if and only if it admits a co-orientable taut foliation. It is known that if the Euler class of the taut foliation vanishes, then the fundamental group is left-orderable. In this talk, we will investigate the Euler class of co-orientable taut foliations on 3-manifolds which are obtained by Dehn surgery along a null-homologous knot.

uk: вхід без авторизації

name: Euler class and taut foliations on surgered 3-manifolds


Left relatively convex subgroups

uk: Математика, природничі науки

description: Let G be a group and H be a subgroup of G. We say that H is left relatively convex in G if the left G-set G/H has at least one G-invariant order. When G is left orderable, this holds if and only if H is convex in G under some left ordering of G. We give a criterion for H to be left relatively convex in G that generalizes a well known criterion of Burns and Hale. We then use this criterion to show that all maximal cyclic subgroups are left relatively convex in free groups, in right-angled Artin groups, and in surface groups that are not the Klein-bottle group. The free-group case extends a result of Duncan and Howie. We show that if G is left orderable, then each free factor of G is left relatively convex in G. More generally, for any graph of groups, if each edge group is left relatively convex in each of its vertex groups, then each vertex group is left relatively convex in the fundamental group; this generalizes a result of Chiswell. Finally, we show that all maximal cyclic subgroups in locally residually torsion-free nilpotent groups are left relatively convex. This is a joint work with Yago Antolin and Warren Dicks.

uk: вхід без авторизації


uk: Математика, природничі науки

description: I will describe a geometric problem on families of elliptic operators, which is solved via a deformation to a family of non self-adjoint Fredholm operators. Let $p:M\to S$ be a proper holomorphic projection of complex manifolds. Let $F$ be a holomorphic vector bundle on $M$. We assume that the $H^{(0,p)}(Xs, F|X_s)$ have locally constant dimension. They are the fibers of a holomorphic vector bundle on $S$. The problem we will address is the computation of characteristic classes associated with the above vector bundle in a refinement of the ordinary de Rham cohomology of $S$, its Bott-Chern cohomology, and the proof of a corresponding theorem of Riemann-Roch-Grothendieck. When $M$ is not K\"ahler, none of the existing techniques to prove such a result using the fiberwise Dolbeault Laplacians can be used. The solution is obtained via a proper deformation of the corresponding Dolbeault Laplacians to a family of hypoelliptic Laplacians, for which the corresponding result can be proved. This deformation is made to destroy the geometric obstructions which exist in the elliptic theory, like the fact the metric should be K\"ahler, or the K\"ahler form to be $\bar\partial\partial$-closed.

uk: вхід без авторизації

name: A Riemann-Roch theorem in Bott-Chern cohomology


uk: Математика, природничі науки

description: In this talk I will overview a new gauge-theoretical approach to the Hull-Strominger system using holomorphic string algebroids. In the smooth setup, a string algebroid provides an infinitesimal version of a principal bundle for the string group. The main focus will be on the consequences of this approach for the existence and uniqueness problem, as well as for the moduli space metric. The discussion will be illustrated by a key example. Joint work with Rubio, Tipler, and Shahbazi.

uk: вхід без авторизації

name: The Hull-Strominger system and holomorphic string algebroids


uk: Математика, природничі науки

description: Generalized Kähler-Ricci solitons are canonical geometric structures on complex, non-Kähler manifolds. In this talk I will give a complete classification of such structures on complex surfaces, which is joint work with Y. Ustinovskiy.

uk: вхід без авторизації

name: Generalized Kähler-Ricci solitons on complex surfaces


uk: Математика, природничі науки

uk: вхід без авторизації

name: SMOOTH RATIONAL DEFORMATIONS OF SINGULAR CONTRACTIONS OF CLASS VII SURFACES


uk: Математика, природничі науки

uk: вхід без авторизації

name: Locally conformally Kähler manifolds with holomorphic Lee field


uk: Математика, природничі науки

description: I will discuss the behavior of the Chern-Ricci flow on compact complex surfaces, emphasizing some open questions and new directions.

uk: вхід без авторизації

name: The Chern-Ricci flow and complex surfaces


Recent progress in anomaly flow

uk: Математика, природничі науки

description: The Hull-Strominger system describes the geometry of compactifications of heterotic superstrings with flux, which can be viewed as a generalization of Ricciflat Kahler metrics on non-Kahler Calabi-Yau manifolds. To overcome the difficulty of lacking ddbar-lemma, Phong-Picard-Zhang initiated the program of Anomaly flow to understand the Hull-Strominger system. It has been proved in many cases that the Anomaly flow serves as an effective way to investigate the Hull-Strominger system and in general canonical metrics on complex manifolds, such as giving new proofs of the Calabi-Yau theorem and the existence of Fu-Yau solution. In this talk, we present some new progress on the Anomaly flow, including the behavior of Anomaly flow on generalized Calabi-Gray manifolds and a unification of the Anomaly flow with vanishing slope parameter and the Kahler-Ricci flow, which further allows us to generalize the notion of the Anomaly flow to arbitrary complex manifolds. This talk is based on joint work with Z.-J. Huang, D.H. Phong and S. Picard.

uk: вхід без авторизації


uk: Математика, природничі науки

description: Deligne, Griffiths, Morgan and Sullivan famously characterised the \partial\bar\partial-Lemma as by the following property: The double complex of forms decomposes as a direct sum of two kinds of irreducible subcomplexes: 'Squares' and 'dots', where only the latter contribute to cohomology. In this talk, we explore the implications of the following folklore generalisation of this: Every (suitably bounded) double complex decomposes into irreducible complexes and these are 'squares' and 'zigzags', with a dot being a zigzag of length 1. This yields insight into the structure of and relation between the various cohomology groups. Applied to complex manifolds, we obtain, among others, Serre duality for all pages of the FSS, a three space decomposition on the middle cohomology and new bimeromorphic invariants. We end the talk with several open questions.

uk: вхід без авторизації

name: Zigzags and the cohomology of complex manifolds


uk: Математика, природничі науки

uk: вхід без авторизації

name: Non-Kähler metrics with torus symmetry and Solutions to the Hull-Strominger system

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery


The Yamabe invariant of Inoue surfaces

uk: Математика, природничі науки

description: The Yamabe invariant is a real-valued diffeomorphism invariant coming from Riemannian geometry. Using Seiberg-Witten theory, LeBrun showed that the sign of the Yamabe invariant of a Kähler surface is determined by its Kodaira dimension. We show that the Yamabe invariant of Inoue surfaces and their blowups is zero which demonstrates that the non-Kähler analogue of LeBrun's theorem does not hold.

uk: вхід без авторизації


On a class of Kato manifolds

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

description: I will discuss the existence of special Lagrangian torus fibrations on log Calabi-Yau manifolds constructed from del Pezzo surfaces, and some progress towards establishing SYZ mirror symmetry for these non-compact Calabi-Yau manifolds. This is joint work with A. Jacob and Y.-S. Lin.

uk: вхід без авторизації

name: Towards SYZ mirror symmetry for Del Pezzo surfaces


uk: Математика, природничі науки

description: I will introduce a Fr\"olicher-type spectral sequence that is valid for all almost complex manifolds, yielding a natural Dolbeault cohomology theory for non-integrable structures and a rich theory surrounding it. As an application, we will see how Dolbeault cohomology may be used to detect the non-existence of compatible nearly K\"ahler metrics. In fact, for nearly K\"ahler manifolds, the Frölicher spectral sequence always degenerates at $E_2$, and so the second page recovers the Hodge-Verbitsky decomposition. I will end with a list of open questions that would be great to discuss with the participants during the workshop. This is joint work with Scott Wilson.

uk: вхід без авторизації

name: Dolbeault cohomology for almost complex manifolds


uk: Математика, природничі науки

description: The cone of nef (1,1) real Bott-Chern cohomology classes on a compact complex manifold is defined in analogy with the Kahler case, as the cone of classes which admit representatives with arbitrarily small negative part. On a K\"ahler manifold this coincides with the closure of the Kahler cone. I will review some basic open problems about these classes, which are either trivial or known in the Kahler case, and I will present partial progress towards some of these (joint with S. Kolodziej and B. Weinkove) and some speculations.

uk: вхід без авторизації

name: Some questions about nef (1,1)-classes on non-Kähler manifolds


A geometric flow of Balanced metrics

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

description: The symmetries of the Hodge diamond of a Kähler manifold provide many non-trivial conditions on both the Hodge numbers and the Betti numbers of the underlying manifold. In this talk I will describe generalizations of these to the setting of Hermitian and almost Kähler manifolds. Both discussions involve zeroeth order terms that vanish in the Kähler case, and yield an interesting representation of sl(2) on a naturally defined subspace of the harmonic forms. I'll explain several topological corollaries involving Betti numbers and the fundamental group, which is joint work with Joana Cirici. The two discussions have some interesting and yet unexplained algebraic mirror-type symmetry between them, which may lead the participants to interesting questions for future research.

uk: вхід без авторизації

name: Topological implications of Kähler-type symmetries for Hermitian and Almost Kähler manifolds


The Taub-Nut Ambitoric Structure

uk: Математика, природничі науки

description: We show that any K\"ahler metric pertaining to the Taub-NUT hyperkaehler structure on $\mathbb{R} ^4 comes naturally coupled with a complete K\"ahler surface isomorphic to a Bryant self-dual K\"ahler metric on \mathbb{C} ^2 to form a regular ambitoric structure of parabolic type.

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: ∂∂¯-Complex symplectic and Calabi–Yau manifolds: Albanese map, deformations and period maps


Optimal transport

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Multi-Representation Manifold Learning on Fibre Bundles


uk: Математика, природничі науки

uk: вхід без авторизації

name: On the Continuum Between Models, Data-Driven Discovery and Machine Learning: Mapping the Continuum of Molecular Conformations Using Cryo-Electron Microscopy


uk: Математика, природничі науки

uk: вхід без авторизації

name: Group synchronization on complex networks: nonconvex optimization and Kuramoto model


uk: Математика, природничі науки

uk: вхід без авторизації

name: Sharpness, Restart, and Compressed Sensing Performance


uk: Математика, природничі науки

uk: вхід без авторизації

name: Ulam’s game and phase retrieval with random binary questions


uk: Математика, природничі науки

uk: вхід без авторизації

name: Sparse Multiscale with Phase to model Deep Neural Networks


uk: Математика, природничі науки

uk: вхід без авторизації

name: Dimension independent bounds for approximation of smooth functions on metric spaces


uk: Математика, природничі науки

uk: вхід без авторизації

name: Fundamental limits of deep neural network learning


uk: Математика, природничі науки

uk: вхід без авторизації

name: On the convex geometry of blind deconvolution


uk: Математика, природничі науки

uk: вхід без авторизації

name: Convergence of gradient flows for learning deep linear networks


uk: Математика, природничі науки

uk: вхід без авторизації

name: Graph neural networks for combinatorial optimization problems on graphs


uk: Математика, природничі науки

uk: вхід без авторизації

name: What is the role of curvature in complexity of optimization on manifolds?

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery


Geometry-based Data Exploration

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Estimating Fourier-sparse signals without a frequency gap


Zink-Silberoxid-Batterie

keywords:
fachfremd Unterrichten
Chemie
Experiment
Elektrochemie
Redoxreaktion
Metalle
Zink
Silber
Silberoxid
galvanisches Element
Elektrolyse
Schüler:innenversuch

uk: Математика, природничі науки

uk: вхід без авторизації

name: Institut für mathematische, naturwissenschaftliche und technische Bildung


uk: Математика, природничі науки

description: I will explain a recently discovered mysterious property in a variety of stochastic systems ranging from the six-vertex model and to the directed polymers, last passage percolation, Kardar-Parisi-Zhang equation, and Airy sheet. Vaguely speaking, the property says that the multi-point joint distributions are unchanged when some (but not necessarily all!) points of observations are shifted. The property leads to explicit computations for the previously inaccessible joint distributions in all these settings.

uk: вхід без авторизації

name: Shift invariance for the six-vertex model and directed polymers


uk: Математика, природничі науки

description: The Yang-Baxter equation states equality of certain local partition functions of a vertex model. If the terms of the Yang-Baxter equation are nonnegative, we can turn it into a a Markov map, which randomly maps objects from one side of the identity into objects on the other side. This idea brings a number of nice applications to lozenge tilings and interacting particle systems.

uk: вхід без авторизації

name: From Yang-Baxter equation to Markov maps


uk: Математика, природничі науки

description: In this talk I will review the results on the universality of height fluctuations in interacting dimer models, obtained in collaboration with F. Toninelli and V. Mastropietro in a recent series of papers. The class of models of interest are close-packed dimers on the square lattice, in the presence of small but extensive perturbations that make them non-determinantal. Examples include the 6-vertex model close to the free-fermion point and the dimer model with plaquette interaction. By tuning the edge weights, one can impose a non-zero average tilt for the height function, so that the considered models are in general not symmetric under discrete rotations and reflections. It is well known that, in the determinantal case, height fluctuations in the massless (or `liquid') phase scale to a Gaussian log-correlated field and their amplitude is a universal constant, independent of the tilt. Our main result is the following: when the perturbation strength is sufficiently small, log-correlations survive, with amplitude A that, generically, depends non-trivially and non-universally on the perturbation strength and on the tilt. Moreover, the amplitude A satisfies a universal scaling relation (`Haldane' or `Kadanoff' relation), saying that it equals the anomalous exponent of the dimer-dimer correlation. The proof is based on a combined use of fermionic Renormalization Group techniques, lattice Ward Identities for the lattice model and emergent Ward Identities for the infrared fixed point theory.

uk: вхід без авторизації

name: Universal fluctuations and scaling relations in interacting dimer models


uk: Математика, природничі науки

description: We consider uniformly random lozenge tilings of essentially arbitrary domains and show that the local statistics of this model around any point in the liquid region of its limit shape are given by the infinite-volume, translation-invariant, extremal Gibbs measure of the appropriate slope. In this talk, we outline a proof of this result, which proceeds by locally coupling a uniformly random lozenge tiling with a model of Bernoulli random walks conditioned to never intersect. Central to implementing this procedure is to establish a local law for the random tiling, which states that the associated height function is approximately linear on any mesoscopic scale.

uk: вхід без авторизації

name: Universality for Lozenge Tiling Local Statistics


Darboux integrable gradient models

uk: Математика, природничі науки

description: The five-vertex model is a generalization of the lozenge tiling model, in which certain adjacent dimers interact. It is solvable by Bethe Ansatz. We give an explicit expression for the free energy and surface tension, and show how to parameterize limit shapes explicitly with analytic functions. We similarly solve the "isoradial" version of the model. This talk is based on joint works with de Gier, Watson and Prause.

uk: вхід без авторизації


Spins, percolation and height functions

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

description: Ashkin-Teller model is a classical four-component spin model introduced in 1943. It can be viewed as a pair of Ising models tau and tau’ with parameter J that are coupled by assigning parameter U for the interaction of the products tau*tau’ at every two neighbouring vertices. On the self-dual curve sinh 2J = e^{-2U}, the Ashkin-Teller model can be coupled with the six-vertex model with parameters a=b=1, c=coth 2J and is conjectured to be conformally invariant. The latter model has a height-function representation. We show that the height at a given face diverges logarithmically in the size of the domain when c=2 and remains uniformly bounded when c>2. In the latter case we obtain a complete description of translation-invariant Gibbs states and deduce that the Ashkin-Teller model on the self-dual line exhibits the following symmetry-breaking whenever J < U: correlations of spins tau and tau’ decay exponentially fast, while the product tau*tau’ is ferromagnetically ordered. The proof uses the Baxter-Kelland-Wu coupling between the six-vertex and the random-cluster models, as well as the recent results establishing the order of the phase transition in the latter model. However, in the talk, we will focus mostly on other parts of the proof: - description of the height-function Gibbs states via height-function mappings and T-circuits, - coupling between the Ashkin-Teller and the six-vertex models via an FK-Ising-type representation of these two models. (this is joint work with Ron Peled)

uk: вхід без авторизації

name: Six-vertex and Ashkin-Teller models: order/disorder phase transition


uk: Математика, природничі науки

description: We give a short proof of the discontinuity of phase transition for the random-cluster model on the square lattice with parameter q>4. This result was recently shown by Duminil-Copin, Gagnebin, Harel, Manolescu and Tassion via the so-called Bethe ansatz for the six-vertex model. Our proof also exploits the connection to the six-vertex model, but does not rely on the Bethe ansatz. Our argument is soft and only uses very basic properties of the random-cluster model. Joint work with Gourab Ray.

uk: вхід без авторизації

name: A short proof of the discontinuity of phase transition in the planar random-cluster model with q > 4


uk: Математика, природничі науки

description: We study asymptotics of perfect matchings on a large class of graphs called the contracting square-hexagon lattice,whichis constructed row by row from either a row of a square grid or a row of a hexagonal lattice. We assign thegraph periodicedge weights with period 1*n, and consider the probability measure of perfect matchings in which theprobability of eachconfiguration is proportional to the product of edge weights. We show that the partition function ofperfect matchings onsuch a graph can be computed explicitly by a Schur function depending on the edge weights. Byanalyzing the asymptoticsof the Schur function, we then prove the Law of Large Numbers (limit shape) and the CentralLimit Theorem (convergenceto the Gaussian free field) for the corresponding height functions. We also show that thedistribution of certain type ofdimers near the turning corner is the same as the eigenvalues of Gaussian Unitary Ensemble,and explicitly study thecurve separating the liquid region and the frozen region for certain boundary conditions.

uk: вхід без авторизації

name: Limit shape of perfect matchings on square-hexagon lattice


Dimers and circle patterns

uk: Математика, природничі науки

description: In this talk I will describe a correspondence between dimer model on planar bipartite graphs and circle pattern embedding of these graphs, that is, embeddings of these graphs so that each face is cyclic. This correspondence is the key for studying Miquel dynamics, a discrete integrable system on circle patterns. Time permitting, I will explain how Tutte embeddings for resistor networks and s-embeddings for Ising models arise as special cases. This is joint work with Richard Kenyon (Yale University), Wai Yeung Lam (University of Luxembourg) and Marianna Russkikh (MIT).

uk: вхід без авторизації


uk: Математика, природничі науки

description: We discuss a concept of `perfect t-embeddings’, or `p-embeddings', of weighted bipartite planar graphs. (T-embeddings also appeared under the name Coulomb gauges in a recent work of Kenyon, Lam, Ramassamy and Russkikh.) We believe that these p-embeddings always exist and that they are good candidates to recover the complex structure of big bipartite planar graphs carrying a dimer model. To support this idea, we first develop a relevant theory of discrete holomorphic functions on t-embeddings; this theory unifies Kenyon's holomorphic functions on T-graphs and s-holomorphic functions coming from the Ising model. Further, given a sequence of (abstract) planar graphs G_n and their p-embeddings T_n onto the unit disc D, assume that (i) the faces of T_n satisfy certain technical assumptions in the bulk of D; (ii) the size of the associated origami maps O_n tends to zero as n grows (again, on each compact subset of D). We prove that (i)+(ii) imply the convergence of the fluctuations of the dimer height functions on G_n (provided that these graphs are embedded by T_n), to the GFF on the unit disc D equipped with the standard complex structure. Though this is not fully clear at the moment, we conjecture that the origami maps O_n are always small in absence of frozen regions and gaseous bubbles, so our theorem can be eventually applied to all such cases. Moreover, the same techniques are applicable in the situation when the limit of the origami maps arising from a sequence of p-embeddings is a Lorenz-minimal surface, in this situation one eventually obtains the GFF in the conformal parametrization of this surface. In a related joint work with Sanjay Ramassamy we argue that such a Lorenz-minimal surface indeed arises in the case of classical Aztec diamonds; a general conjecture is that this should `always' be the case due to a link between p-embeddings and a representation of the dimer model in the Plucker quadric. Time permitting, we also indicate how the theory of t-holomorphic functions specifies to the Ising case and discuss related results on conformal invariance of the Ising model as well as a more general perspective.

uk: вхід без авторизації

name: Perfect t-embeddings of bipartite planar graphs and the convergence to the GFF -I


uk: Математика, природничі науки

uk: вхід без авторизації

name: Perfect t-embeddings of bipartite planar graphs and the convergence to the GFF -II


The dimer model on Riemann surfaces

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

description: I will discuss the local structure of the boundary at the rough-smooth (or liquid-gas) interface in the two-periodic Aztec diamond. At the frozen-rough interface we have a well-defined boundary path which converges to the Airy process. At the rough-smooth smooth boundary the situation is more complicated although here also we expect to have an Airy process. Which geometric structure converges to the Airy process? At this boundary we see both local and long range structures. There should be a last path among these long range structures that converges to the Airy process as can be seen in pictures. We will not prove this but discuss some results in this direction. This is joint work with Vincent Beffara and Sunil Chhita.

uk: вхід без авторизації

name: On the rough-smooth interface in the two-periodic Aztec diamond


uk: Математика, природничі науки

description: We will discuss some properties of the time process for the boundary of the North polar region of the Aztec diamond, based on analogue results obtained in other models in the KPZ universality class.

uk: вхід без авторизації

name: Time-time correlation for the South polar region of the Aztec diamond


uk: Математика, природничі науки

description: For dimers and other models of random surfaces, limit shapes appear when boundary conditions force a certain response of the system. The main mathematical tool to study these responses is a variational principle which states that the limiting profile of the system must maximizes the integral of an entropy function often named surface tension. As a consequence, the strict convexity of the surface tension plays a crucial role as it forces the asymptotic profile which maximizes this integral to be unique. In this talk we will show that all models of Lipschitz random surfaces which are stochastically monotonic must have a strictly convex surface tension (joint with Piet Lammers).

uk: вхід без авторизації

name: Uniqueness of the limiting profile for monotonic Lipschitz random surfaces


uk: Математика, природничі науки

description: I will discuss how dimer models and other statistical physics models are related to Laplacian determinants, both on the discrete level and on the continuum level. In particular, I will recall the geometric meaning of the so-called zeta-regularized determinant of the Laplacian, as it is defined on a compact surface, with or without boundary. Using an appropriate regularization, we find that a Brownian loop soup of intensity c has a partition function described by the (-c/2)th power of the determinant of the Laplacian. In a certain sense, this means that decorating a random surface by a Brownian loop soup of intensity c corresponds to weighting the law of the surface by the (-c/2)th power of the determinant of the Laplacian. I will then introduce a method of regularizing a unit area LQG sphere, and show that weighting the law of this random surface by the (-c'/2)th power of the Laplacian determinant has precisely the effect of changing the matter central charge from c to c'. Taken together with the earlier results, this provides a way of interpreting an LQG surface of matter central charge c as a pure LQG surface decorated by a Brownian loop soup of intensity c. This is based on joint work with Morris Ang, Minjae Park, and Joshua Pfeffer.

uk: вхід без авторизації

name: Smooth planar maps and Laplacian determinants


The eight-vertex model via dimers

uk: Математика, природничі науки

description: The eight-vertex model is an ubiquitous description that generalizes several spin systems, "ice-type" six-vertex models, and others. In a special "free-fermion" regime, it is known since the work of Fan, Lin, Wu in the late 60s that the model can be mapped to non-bipartite dimers. In this talk I will show how to transform these non-bipartite dimers into bipartite ones, which allows for a deep, rigorous study on generic planar graphs. I will mention a few consequences: computation of long-range correlations and critical exponents, critical regimes, and their "exact" application to Z-invariant regimes on isoradial graphs.

uk: вхід без авторизації


Pseudothermalization of the QGP

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Pre-scaling, hydrodynamic attractors and entropy production in heavy ion collisions


uk: Математика, природничі науки

uk: вхід без авторизації

name: Collective flow in large and small systems (VIRTUAL SEMINAR)

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery


uk: Математика, природничі науки

uk: вхід без авторизації

name: Pushing the boundaries of fluid dynamics


uk: Математика, природничі науки

uk: вхід без авторизації

name: A review of a Schwinger-Keldysh effective action for hydrodynamics


uk: Математика, природничі науки

uk: вхід без авторизації

name: Perfect-fluid hydrodynamics of particles with spin 1/2 (with classical treatment of spin)


What attracts to attractors?

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: From spin chains to real-time thermal field theory using tensor networks


Hydrodynamics near a critial point

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Relativistic fluid dynamics of spin-polarized systems and spin-vorticity coupling


A new look on hydrodynamic attractors

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: A quantum information perspective on relativistic fluid dynamics and quantum fields out-of-equilibrium


uk: Математика, природничі науки

uk: вхід без авторизації

name: Adiabatic hydrodynamization in rapidly-expanding quark gluon plasma


Eppur converge (AND YET IT CONVERGES)

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Analytical solutions and attractors of higher-order viscous hydrodynamics


uk: Математика, природничі науки

uk: вхід без авторизації

name: Initializing Conserved Charges for BSQ hydrodynamics


uk: Математика, природничі науки

description: Existing proofs that deduce BPP=P from circuit lower bounds convert randomized algorithms into deterministic algorithms with a large polynomial slowdown. We convert randomized algorithms into deterministic ones with little slowdown. Specifically, assuming exponential lower bounds against nondeterministic circuits, we convert any randomized algorithm that errs rarely into a deterministic algorithm with a similar running time (with pre-processing), and any general randomized algorithm into a deterministic algorithm whose runtime is slower by a nearly linear multiplicative factor. Our results follow from a new, nearly optimal, explicit pseudorandom generator fooling circuits of size s with seed length (1+alpha)log s for an arbitrarily small constant alpha>0, under the assumption that there exists a function f in E that requires nondeterministic circuits of size at least 2^{(1-alpha')n}, where alpha = O(alpha'). The construction uses, among other ideas, a new connection between pseudoentropy generators and locally list recoverable codes.

uk: вхід без авторизації

name: Nearly Optimal Pseudorandomness From Hardness


uk: Математика, природничі науки

description: For every constant d >= 3 and epsilon > 0, we give a deterministic poly(n)-time algorithm that outputs a d-regular graph on Θ(n) vertices that is epsilon-near-Ramanujan; i.e., its eigenvalues are bounded in magnitude by 2sqrt(d-1)+epsilon (excluding the single trivial eigenvalue of d).

uk: вхід без авторизації

name: Explicit near-Ramanujan graphs of every degree


uk: Математика, природничі науки

description: We describe new ways of constructing pseudorandom generators for Boolean functions that satisfy certain bounds on their Fourier spectrum. We discuss the possibility of using this approach to construct pseudorandom generators for complexity classes that have eluded researches for decades. Based on joint works with Pooya Hatami, Kaave Hosseini, Shachar Lovett and Avishay Tal.

uk: вхід без авторизації

name: Pseudorandomness from the Fourier Spectrum


uk: Математика, природничі науки

uk: вхід без авторизації

name: Near-Optimal Pseudorandom Generators for Constant-Depth Read-Once Formulas


uk: Математика, природничі науки

description: We prove Sylvester-Gallai type theorems for quadratic polynomials. Specifically, we prove that if a finite collection Q, of irreducible polynomials of degree at most 2, satisfy that for every two polynomials Q1,Q2 ∈ Q there is a third polynomial Q3∈Q so that whenever Q1 and Q2 vanish then also Q3 vanishes, then the linear span of the polynomials in Q has dimension O(1). We also prove a colored version of the theorem: If three finite sets of quadratic polynomials satisfy that for every two polynomials from distinct sets there is a polynomial in the third set satisfying the same vanishing condition then all polynomials are contained in an O(1)-dimensional space. This answers affirmatively two conjectures of Gupta [Electronic Colloquium on Computational Complexity (ECCC), 21:130, 2014] that were raised in the context of solving certain depth-4 polynomial identities. To obtain our main theorems we prove a new result classifying the possible ways that a quadratic polynomial Q can vanish when two other quadratic polynomials vanish. Our proofs also require robust versions of a theorem of Edelstein and Kelly (that extends the Sylvester-Gallai theorem to colored sets).

uk: вхід без авторизації

name: Sylvester-Gallai Type Theorems for Quadratic Polynomials


uk: Математика, природничі науки

uk: вхід без авторизації

name: Efficient Construction of Rigid Matrices Using an NP Oracle


uk: Математика, природничі науки

description: Lifting theorems are theorems that relate the query complexity of a function f : {0, 1}^n → {0, 1} to the communication complexity of the composed function f ◦ g^n, for some “gadget” g : {0, 1}^b × {0, 1}^b →{0, 1}. Such theorems allow transferring lower bounds from query complexity to the communication complexity, and have seen numerous applications in the recent years. In addition, such theorems can be viewed as a strong generalization of a direct-sum theorem for the gadget g. We prove a new lifting theorem that works for all gadgets g that have logarithmic length and exponentially-small discrepancy, for both deterministic and randomized communication complexity. Thus, we increase the range of gadgets for which such lifting theorems hold considerably. Our result has two main motivations: First, allowing a larger variety of gadgets may support more applications. In particular, our work is the first to prove a randomized lifting theorem for logarithmic-size gadgets, thus improving some applications the theorem. Second, our result can be seen a strong generalization of a direct-sum theorem for functions with low discrepancy. Joint work with Arkadev Chattopadhyay, Yuval Filmus, Or Meir, Toniann Pitassi

uk: вхід без авторизації

name: Randomized Query to Communication lifting for low discrepancy gadgets


uk: Математика, природничі науки

uk: вхід без авторизації

name: The Log-Approximate-Rank Conjecture is False

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery


uk: Математика, природничі науки

uk: вхід без авторизації

name: The sunflower conjecture and connections to TCS


Private hypothesis selection

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Reconstructing arithmetic formulas using lower bound proof techniques


uk: Математика, природничі науки

uk: вхід без авторизації

name: Tensor Isomorphism: completeness, graph-theoretic methods, and consequences for Group Isomorphism


uk: Математика, природничі науки

uk: вхід без авторизації

name: The ultrafilter and almost disjointness numbers


uk: Математика, природничі науки

uk: вхід без авторизації

name: Preservation theorems for finite support iterations I.


uk: Математика, природничі науки

uk: вхід без авторизації

name: Preservation theorems for finite support iterations II.


Two proofs of Cichon's maximum I.

uk: Математика, природничі науки

uk: вхід без авторизації


Two proofs of Cichon's maximum II.

uk: Математика, природничі науки

uk: вхід без авторизації


Higher cardinal invariants I.

uk: Математика, природничі науки

uk: вхід без авторизації


Higher cardinal invariants II.

uk: Математика, природничі науки

uk: вхід без авторизації


YPFA implies MRP

uk: Математика, природничі науки

uk: вхід без авторизації


Ideal topogies on 2^\kappa

uk: Математика, природничі науки

uk: вхід без авторизації


Independence results for the 2-torus

uk: Математика, природничі науки

uk: вхід без авторизації


Mad families and the modal logic of N∗

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: The complexity of the isomorphism relation between oligomorphic groups


uk: Математика, природничі науки

uk: вхід без авторизації

name: Weihrauch reducibility, highness classes, cardinal characteristics, and forcing I.


uk: Математика, природничі науки

uk: вхід без авторизації

name: Weihrauch reducibility, highness classes, cardinal characteristics, and forcing II.


uk: Математика, природничі науки

uk: вхід без авторизації

name: Simultaneously vanishing higher derived limits


uk: Математика, природничі науки

uk: вхід без авторизації

name: Definable (co)homology, the rigidity of solenoids, and classification by (co)cycles


uk: Математика, природничі науки

uk: вхід без авторизації

name: Small almost disjoint families with applications to Banach spaces


uk: Математика, природничі науки

uk: вхід без авторизації

name: Convergence of measures on minimally generated boolean algebras


uk: Математика, природничі науки

uk: вхід без авторизації

name: On a type of second order variational problem in L-infinity.


uk: Математика, природничі науки

uk: вхід без авторизації

name: Non simple blow-up phenomena for the singular Liouville equation.


uk: Математика, природничі науки

uk: вхід без авторизації

name: Some Ginzburg-Landau problems for vector fields on surfaces


uk: Математика, природничі науки

uk: вхід без авторизації

name: Minkowski Inequality and nonlinear potential theory (part 1)

name: Banff International Research Station (BIRS) for Mathematical Innovation and Discovery


On the Sobolev quotient in CR geometry

uk: Математика, природничі науки

uk: вхід без авторизації


uk: Математика, природничі науки

uk: вхід без авторизації

name: Multiple single peak solutions to the Gelfand problem.


uk: Математика, природничі науки

uk: вхід без авторизації

name: On the bubbling solutions of the Maxwell-Chern-Simons model on flat torus.


uk: Математика, природничі науки

uk: вхід без авторизації

name: Multiple end solutions of the generalized second Painlevè equation


uk: Математика, природничі науки

uk: вхід без авторизації

name: Bubbling nodal solutions for a large perturbation of the Moser-Trudinger equation on planar domains


uk: Математика, природничі науки

uk: вхід без авторизації

name: Some canonical metrics on four manifolds: rigidity and existence