Symplectic Geometry
《Symplectic Geometry》 · 第 15 页 · Section 1.7，Topological symmetries（纽结相等按环境同痕解释）
Let \(r:\mathbb R^3\longrightarrow\mathbb R^3\) be the map \((x,y,z)\longmapsto(-x,-y,-z)\); 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 \(K^*\). […] If \(K\) and its mirror image are different then we say that \(K\) is cheiral (handed) and it occurs in a left-handed (laevo) and a right-handed (dextro) form. If \(K=K^*\) then we say that \(K\) is acheiral or amphicheiral. The reflection of \(K\) is independent of the choice of \(r\): the image of \(K\) under any other orientation-reversing homeomorphism will be ambient isotopic to \(r(K)\).