English

Symplectic Rigidity of Real Bidisc

Symplectic Geometry 2015-09-28 v1

Abstract

Let D\mathbb{D} be the unit disc in C\mathbb{C}, then Dn(r)\mathbb{D}^n(r) is the complex or symplectic nn-discs of radius rr. Let zj=xj+iyjC,j=1,2z_j = x_j+iy_j\in\mathbb{C}, j=1,2 and DR2={(z1,z2):x12+x22<1,y12+y22<1}\mathbb{D}_{\mathbb{R}}^2=\{(z_1,z_2) : |x_1|^2+|x_2|^2<1,|y_1|^2+|y_2|^2<1\} be the real bidisc. In this paper we will prove the following two theorems: 1) If TO(4)T\in O(4) is an orthogonal transformation on R4\mathbb{R}^4, then T(D2)T(\mathbb{D}^2) is symplectomorphic to D2\mathbb{D}^2 w.r.t. the standard symplectic form on R4\mathbb{R}^4 if and only if TT is unitary or conjugate to unitary. 2) For r1r\geq 1 and n2n\geq 2, DR2×Dn2(r)\mathbb{D}_{\mathbb{R}}^2\times \mathbb{D}^{n-2}(r) and D2×Dn2(r)\mathbb{D}^2\times \mathbb{D}^{n-2}(r) are not symplectomorphic w.r.t. the standard symplectic form on Cn\mathbb{C}^n.

Keywords

Cite

@article{arxiv.1509.07579,
  title  = {Symplectic Rigidity of Real Bidisc},
  author = {Yat-Sen Wong},
  journal= {arXiv preprint arXiv:1509.07579},
  year   = {2015}
}