(Almost) tight bounds for randomized and quantum Local Search on hypercubes and grids
| dc.creator | Zhang, Shengyu | |
| dc.date | 2005-04-12 | |
| dc.date | 2005-05-30 | |
| dc.date.accessioned | 2026-07-07T06:12:34Z | |
| dc.date.available | 2026-07-07T06:12:34Z | |
| dc.description | The Local Search problem, which finds a local minimum of a black-box function on a given graph, is of both practical and theoretical importance to many areas in computer science and natural sciences. In this paper, we show that for the Boolean hypercube $\B^n$, the randomized query complexity of Local Search is $Θ(2^{n/2}n^{1/2})$ and the quantum query complexity is $Θ(2^{n/3}n^{1/6})$. We also show that for the constant dimensional grid $[N^{1/d}]^d$, the randomized query complexity is $Θ(N^{1/2})$ for $d \geq 4$ and the quantum query complexity is $Θ(N^{1/3})$ for $d \geq 6$. New lower bounds for lower dimensional grids are also given. These improve the previous results by Aaronson [STOC'04], and Santha and Szegedy [STOC'04]. Finally we show for $[N^{1/2}]^2$ a new upper bound of $O(N^{1/4}(\log\log N)^{3/2})$ on the quantum query complexity, which implies that Local Search on grids exhibits different properties at low dimensions. | |
| dc.description | 18 pages, 1 figure. v2: introduction rewritten, references added. v3: a line for grant added. v4: upper bound section rewritten | |
| dc.identifier | https://arxiv.org/abs/quant-ph/0504085 | |
| dc.identifier | http://arxiv.org/abs/quant-ph/0504085 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/92823 | |
| dc.subject | Quantum Physics | |
| dc.title | (Almost) tight bounds for randomized and quantum Local Search on hypercubes and grids | |
| dc.type | text |