Schreiber Greifswald 2026

A talk that I once gave:

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• Urs Schreiber$\;\;$ (on work at CQTS with H. Sati):

  
  

  Bulk-Edge Correspondence via Higher Gauge Theory

  manuscript: pdf, arXiv:2605.10232

  talk slides: pdf

  

  
  

  talk at:

  Higher Differential Geometry

  Alfried Krupp Wissenschaftskolleg, Greifswald, 4-6 May 2026

  
  

  Abstract. More profound than bulk topological order of quantum materials is only its unwinding via gapless excitations along boundaries of the sample. We recast this bulk-edge correspondence — for the experimentally relevant case of fractional quantum Hall (FQH) systems — in terms of higher gauge theory, controlled by choices of classifying fibrations. For FQH systems we identify the complex Hopf fibration as classifying the bulk/boundary topological effects, and find that it yields a non-Lagrangian reconstruction of Floreanini-Jackiw/Wess-Zumino-Witten chiral edge currents.

  Remarkably, the resulting effective FQH theory turns out to be “geometrically engineered” on M2/M5-brane probes of A-type orbi-singularities in 11D supergravity, globally completed by proper flux quantization in twisted equivariant differential (TED) Cohomotopy: Here the M-string ends of M2-branes on M5-branes engineer the FQH liquid's boundary. This geometric engineering on M-branes might naturally eludicate the curious combination of $W_\infty$-symmetry and of super-symmetry that is known (I, II) to govern the collective excitations of FQH liquids at long wavelengths.

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(Urs Schreiber, Grigorios Giotopoulos, Christian Saemann, Carlos Shahbazi; Greifswald, 4th May 2026)

Related talks:

• The $1 Million Puzzle: Hadrons and Quantum Computers — Why Modern Physics Needs a New Global Mathematics, public evening lecture at Alfried Krupp Wissenschaftskolleg, Greifswald, 4-6 May 2026

• Higher Gauge Theory via Nonabelian Differential Cohomology

• Complete Topological Quantization of Higher Gauge Fields, lecture series at: Geometry, Higher Structures, and Physics, Bayes Centre, Edinburgh, 8-12 December 2025

• Rethinking FQH Anyons, talk at NYU-NYUAD Workshop on Quantum Matter and Quantum Computing @ Center for Quantum Information Physics, NYU New York, 19-20 May 2025

Related articles:

• Fractional Quantum Hall Anyons via the Algebraic Topology of exotic Flux Quanta

• Flux Quantization on M-Strings