期刊名称:Electronic Colloquium on Computational Complexity
印刷版ISSN:1433-8092
出版年度:2009
卷号:2009
出版社:Universität Trier, Lehrstuhl für Theoretische Computer-Forschung
摘要:We present new faster algorithms for the exact solution of the shortest vector problem in arbitrary lattices. Our main result shows that the shortest vector in any n -dimensional lattice can be found in time 2 3 199 n and space 2 1 325 n . This improves the best previously known algorithm by Ajtai, Kumar and Sivakumar [Proceedings of STOC 2001] which was shown by Nguyen and Vidick [J. Math. Crypto. 2(2):181--207] to run in time 2 5 9 n and space 2 2 95 n . We also present a practical variant of our algorithm which provably uses an amount of space proportional to n , the ``kissing'' constant in dimension n . Based on the best currently known upper and lower bounds on the kissing constant, the space complexity of our second algorithm is provably bounded by 2 0 41 n , and it is likely to be at most 2 0 21 n in practice. No upper bound on the running time of our second algorithm is currently known, but experimentally the algorithm seems to perform fairly well in practice, with running time 2 0 48 n , and space complexity 2 0 18 n .