Title
Parameterized Quantum Query Complexity of Graph Collision
Abstract
We present three new quantum algorithms in the quantum query model for \textsc{graph-collision} problem: \begin{itemize} \item an algorithm based on tree decomposition that uses $O\left(\sqrt{n}t^{\sfrac{1}{6}}\right)$ queries where $t$ is the treewidth of the graph; \item an algorithm constructed on a span program that improves a result by Gavinsky and Ito. The algorithm uses $O(\sqrt{n}+\sqrt{\alpha^{**}})$ queries, where $\alpha^{**}(G)$ is a graph parameter defined by \[\alpha^{**}(G):=\min_{VC\text{-- vertex cover of}G}{\max_{\substack{I\subseteq VC\\I\text{-- independent set}}}{\sum_{v\in I}{\deg{v}}}};\] \item an algorithm for a subclass of circulant graphs that uses $O(\sqrt{n})$ queries. \end{itemize} We also present an example of a possibly difficult graph $G$ for which all the known graphs fail to solve graph collision in $O(\sqrt{n} \log^c n)$ queries.
Year
Venue
Field
2013
CoRR
Quantum,Discrete mathematics,Combinatorics,Parameterized complexity,Tree decomposition,Quantum algorithm,Circulant matrix,Independent set,Vertex cover,Treewidth,Mathematics
DocType
Volume
Citations 
Journal
abs/1305.1021
2
PageRank 
References 
Authors
0.51
6
5
Name
Order
Citations
PageRank
Andris Ambainis12000183.24
Kaspars Balodis2176.03
Janis Iraids3186.14
Raitis Ozols4102.89
Juris Smotrovs5517.35