We give three proofs that valuation rings are derived splinters: a geometric proof using the absolute integral closure, a homological proof which reduces the problem to checking that valuation rings are splinters (which is done in the second authors PhD thesis and which we reprise here), and a proof by approximation which reduces the problem to Bhatts proof of the derived direct summand conjecture. The approximation property also shows that smooth algebras over valuation rings are splinters.
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