Relative cycle

In algebraic geometry, a relative cycle is a type of algebraic cycle on a scheme. In particular, let X be a scheme of finite type over a Noetherian scheme S, so that X→S. Then a relative cycle is a cycle on X which lies over the generic points of S, such that the cycle has a well-defined specialization to any fiber of the projection X→S.(Voevodsky & Suslin 2000)

The notion was introduced by Andrei Suslin and Vladimir Voevodsky in 2000; the authors were motivated to overcome some of the deficiencies of sheaves with transfers.

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