Ruka hadi maudhui
The Lumenary
Njia za utafitiGeometry & TopologySomo linapatikana

Symplectic geometry and topology

Optional research direction: the geometry of classical mechanics. Symplectic manifolds and Darboux's theorem, Hamiltonian flows, Moser's trick, moment maps, Gromov's non-squeezing theorem, the Arnold conjecture and Floer homology, and a glimpse of mirror symmetry.

math.geom.symplectic-geometry

Inajengwa juu ya

Masharti ya awali ya lazima 45 (hadi chini kabisa)

Utajifunza

  • Define symplectic manifolds and Hamiltonian vector fields, and derive Hamilton's equations.
  • Prove Darboux's theorem using Moser's trick, showing symplectic manifolds have no local invariants.
  • State Gromov's non-squeezing theorem and the Arnold conjecture, and explain the idea of Floer homology, distinguishing proved cases from open ones.

Fasili

  • A symplectic form on a manifold is a closed, non-degenerate 2-form ω.
  • The Hamiltonian vector field X_H of a function H is defined by ι_{X_H} ω = dH.
  • A symplectomorphism is a diffeomorphism φ with φ*ω = ω.

Nadharia

  • Darboux: every symplectic manifold is locally isomorphic to (ℝ²ⁿ, Σ dxᵢ ∧ dyᵢ).
  • Hamiltonian flows preserve ω and hence volume (Liouville's theorem).
  • Gromov non-squeezing (1985): a ball of radius r embeds symplectically in the cylinder B²(R) × ℝ²ⁿ⁻² only if r ≤ R.

Mawazo potofu ya kawaida

  • Thinking symplectic maps are just volume-preserving maps; in dimension at least 4, non-squeezing shows symplectic maps are far more rigid.
  • Believing symplectic geometry has curvature invariants like Riemannian geometry; by Darboux's theorem there are no local invariants at all.

Ugunduzi wa hiari

  • Complex and Kähler geometry; Hodge theory Every Kähler manifold is symplectic; mirror symmetry conjecturally exchanges the symplectic geometry of one Calabi–Yau manifold with the complex geometry of another.
  • Derived categories Kontsevich's homological mirror symmetry conjecture predicts an equivalence between a Fukaya category (symplectic) and a derived category of coherent sheaves (algebraic).
  • ← Smooth manifolds

Njia za kujifunza

Usomaji zaidi

  • Dusa McDuff and Dietmar Salamon, Introduction to Symplectic Topology (1995)
  • Ana Cannas da Silva, Lectures on Symplectic Geometry (2001)