## Hearing Delzant polytopes from the equivariant spectrum

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- by Emily B. Dryden, Victor Guillemin and Rosa Sena-Dias PDF
- Trans. Amer. Math. Soc.
**364**(2012), 887-910 Request permission

## Abstract:

Let $M^{2n}$ be a symplectic toric manifold with a fixed $\mathbb {T}^n$-action and with a toric Kähler metric $g$. Abreu (2003) asked whether the spectrum of the Laplace operator $\Delta _g$ on $\mathcal {C}^\infty (M)$ determines the moment polytope of $M$, and hence by Delzant’s theorem determines $M$ up to symplectomorphism. We report on some progress made on an equivariant version of this conjecture. If the moment polygon of $M^4$ is generic and does not have too many pairs of parallel sides, the so-called*equivariant spectrum*of $M$ and the spectrum of its associated real manifold $M_{\mathbb {R}}$ determine its polygon, up to translation and a small number of choices. For $M$ of arbitrary even dimension and with integer cohomology class, the equivariant spectrum of the Laplacian acting on sections of a naturally associated line bundle determines the moment polytope of $M$.

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## Additional Information

**Emily B. Dryden**- Affiliation: Department of Mathematics, Bucknell University, Lewisburg, Pennsylvania 17837
- Email: ed012@bucknell.edu
**Victor Guillemin**- Affiliation: Department of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
- Email: vwg@math.mit.edu
**Rosa Sena-Dias**- Affiliation: Centro de Análise Matemática, Geometria e Sistemas Dinâmicos, Departamento de Matemática, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
- Email: senadias@math.ist.utl.pt
- Received by editor(s): August 24, 2009
- Received by editor(s) in revised form: June 18, 2010
- Published electronically: October 4, 2011
- © Copyright 2011
American Mathematical Society

The copyright for this article reverts to public domain 28 years after publication. - Journal: Trans. Amer. Math. Soc.
**364**(2012), 887-910 - MSC (2010): Primary 58J50, 53D20
- DOI: https://doi.org/10.1090/S0002-9947-2011-05412-7
- MathSciNet review: 2846357