期刊名称:Electronic Colloquium on Computational Complexity
印刷版ISSN:1433-8092
出版年度:2002
卷号:2002
出版社:Universität Trier, Lehrstuhl für Theoretische Computer-Forschung
摘要:We prove exponential lower bounds on the length of 2-query locally decodable codes. Goldreich et al. recently proved such bounds for the special case of linear locally decodable codes. Our proof shows that a 2-query locally decodable code can be decoded with only 1 quantum query, and then proves an exponential lower bound for such 1-query locally quantum-decodable codes. We also exhibit q-query locally quantum-decodable codes that are much shorter than the best known q-query classical codes. Finally, we give some new lower bounds for (not necessarily linear) private information retrieval systems.