Affordable Access

Rational approximations and quantum algorithms with postselection

Authors
Type
Preprint
Publication Date
Submission Date
Identifiers
arXiv ID: 1401.0912
Source
arXiv
License
Yellow
External links

Abstract

We study the close connection between rational functions that approximate a given Boolean function, and quantum algorithms that compute the same function using postselection. We show that the minimal degree of the former equals (up to a factor of 2) the minimal query complexity of the latter. We give optimal (up to constant factors) quantum algorithms with postselection for the Majority function, slightly improving upon an earlier algorithm of Aaronson. Finally we show how Newman's classic theorem about low-degree rational approximation of the absolute-value function follows from these algorithms.

Statistics

Seen <100 times