In mathematics two links L0⊂Sn{\displaystyle L_{0}\subset S^{n}} and L1⊂Sn{\displaystyle L_{1}\subset S^{n}} are concordant if there is an embedding f:L0×[0,1]→Sn×[0,1]{\displaystyle f:L_{0}\times [0,1]\to S^{n}\times [0,1]} such that f(L0×{0})=L0×{0}{\displaystyle f(L_{0}\times \{0\})=L_{0}\times \{0\}} and f(L0×{1})=L1×{1}{\displaystyle f(L_{0}\times \{1\})=L_{1}\times \{1\}}.
![{\displaystyle f:L_{0}\times [0,1]\to S^{n}\times [0,1]}](https://wikimedia.org/api/rest_v1/media/math/render/svg/382f5a09d722bbaca7ea6751d7b2b0e85ecaa39e)
