Uniform approximation by (quantum) polynomials
نویسندگان
چکیده
We show that quantum algorithms can be used to re-prove a classical theorem in approximation theory, Jackson’s Theorem, which gives a nearly-optimal quantitative version of Weierstrass’s Theorem on uniform approximation of continuous functions by polynomials. We provide two proofs, based respectively on quantum counting and on quantum phase estimation.
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عنوان ژورنال:
- Quantum Information & Computation
دوره 11 شماره
صفحات -
تاریخ انتشار 2011