mirror image

《Symplectic Geometry》 · 第 15 页 · Section 1.7，Topological symmetries

Suppose we use an orientation-reversing homeomorphism. Let \(r:\mathbb R^3\to\mathbb R^3\) be the map \((x,y,z)\mapsto(-x,-y,-z)\); this is called central inversion or reflection in the origin. The image \(r(K)\) of a knot \(K\) is called the mirror image, reflection, or obverse of \(K\) and is denoted by \(K^*\).