Quest for Fast Partial Search Algorithm

通过快速经典更新在线估计部分转置矩

Online Estimation of Partial Transpose Moments via Fast Classical Updates

本文提出通过快速经典更新方法，在线估计部分转置矩，该方法在保持内存的同时将计算复杂度降低到亚立方级，适用于混合态纠缠认证和PT矩基于相位诊断。

XMDS2: Fast, scalable simulation of coupled stochastic partial differential equations

XMDS2 is a cross-platform, GPL-licensed, open source package for numerically integrating initial value problems that range from a single ordinary differential equation up to systems of coupled stochastic partial differential equations. The equations are described in a high-level XML-based script, and the package generates low-level optionally parallelised C++ code for the efficient solution of those equations. It combines the advantages of high-level simulations, namely fast and low-error development, with the speed, portability and scalability of hand-written code. XMDS2 is a complete redesig…

When is a set of questions to nature together with sharp answers to those questions in one-to-one correspondence with a set of quantum states?

A general question is posed to the quantum community. Partial results are formulated in a self-contained way. In particular, the title question is answered affirmatorily in two cases: 1) The case of spin/ angular momentum of a partcle; 2) A general symmetry situation under certain technical assumptions.

Optimization of Partial Search

Quantum Grover search algorithm can find a target item in a database faster than any classical algorithm. One can trade accuracy for speed and find a part of the database (a block) containing the target item even faster, this is partial search. A partial search algorithm was recently suggested by Grover and Radhakrishnan. Here we optimize it. Efficiency of the search algorithm is measured by number of queries to the oracle. The author suggests new version of Grover-Radhakrishnan algorithm which uses minimal number of queries to the oracle. The algorithm can run on the same hardware which is us…

更快的随机部分迹估计

Faster randomized partial trace estimation

针对量子物理和化学中的部分迹估计问题，提出了一种随机无矩阵算法，通过显式去相关重要子空间降低方差，较现有方法实现数量级加速，并应用于海森堡自旋系统的热力学研究。

Quantum partial search for uneven distribution of multiple target items

Quantum partial search algorithm is approximate search. It aims to find a target block (which has the target items). It runs a little faster than full Grover search. In this paper, we consider quantum partial search algorithm for multiple target items unevenly distributed in database (target blocks have different number of target items). The algorithm we describe can locate one of the target blocks. Efficiency of the algorithm is measured by number of queries to the oracle. We optimize the algorithm in order to improve efficiency. By perturbation method, we find that the algorithm runs the fas…