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Generalized convex toric domains and symplectic embedding problems - Nicki Magill

Nicki Magill discusses generalized convex toric domains and their symplectic embedding problems, revealing insights on obstructions and techniques.

Generalized convex toric domains and symplectic embedding problems - Nicki Magill Watch on YouTube ↗

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This comprehensive presentation explores the structure and embedding properties of generalized convex toric domains within four-dimensional symplectic geometry. It focuses on advanced invariants known as Embedded Contact Homology (ECH) capacities and their asymptotic behaviors to establish new obstructions and insights into symplectic embedding challenges, including packing stability and the existence of infinite staircases in ellipsoid embedding functions. Intended for researchers and practitioners in symplectic topology and geometric analysis, it bridges foundational principles with recent results extending known frameworks to more general settings.

Introduction to Symplectic Manifolds and Embeddings

Symplectic manifolds are smooth manifolds equipped with a closed, non-degenerate 2-form called the symplectic form. Locally, as per Darboux’s theorem, all symplectic manifolds of the same dimension look identical and admit standard form coordinates. This talk focuses on 4-dimensional symplectic manifolds embedded in \(\mathbb{R}^4\) with the standard symplectic structure.

A symplectic embedding between two such manifolds is a smooth embedding preserving the symplectic form, thus preserving an induced volume form. Consequently, a fundamental necessary condition for a symplectic embedding to exist is that the volume of the domain manifold does not exceed that of the target.

However, volume alone does not characterize symplectic embeddings, as revealed by Gromov’s non-squeezing theorem, which restricts embeddings of balls into cylinders based on radius, revealing obstructions beyond volume.

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  1. Generalized Convex Toric Domains: Definitions and Geometry
  2. Affine Perimeter and Its Role in Symplectic Embeddings
  3. Embedded Contact Homology (ECH) Capacities: An Advanced Symplectic Invariant
  4. Subleading Asymptotics of ECH Capacities and Main Theorem
  5. Applications to Symplectic Packing and Embedding Stability
  6. Packing Stability and Full Fillings
  7. Obstruction from Affine Perimeter
  8. Ellipsoid Embedding Functions and Infinite Staircases
  9. Accumulation Point Theorem
  10. Implications for Full Fillings
  11. Classification of Infinite Staircases for Smooth Convex Toric Domains
  12. Key Frameworks and Mental Models
  13. Affine Perimeter (Invariant under \(\mathrm{SL}_2(\mathbb{Z})\))
  14. Subleading Asymptotics of ECH Capacities
  15. Weight Sequence Decomposition
  16. Practical Implications and Takeaways
  17. Action-Oriented Summary
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