5,715 research outputs found
From Schr\"odinger's Equation to the Quantum Search Algorithm
The quantum search algorithm is a technique for searching N possibilities in
only sqrt(N) steps. Although the algorithm itself is widely known, not so well
known is the series of steps that first led to it, these are quite different
from any of the generally known forms of the algorithm. This paper describes
these steps, which start by discretizing Schr\"odinger's equation. This paper
also provides a self-contained introduction to the quantum search algorithm
from a new perspective.Comment: Postscript file, 16 pages. This is a pedagogical article describing
the invention of the quantum search algorithm. It appeared in the July, 2001
issue of American Journal of Physics (AJP
Realization of generalized quantum searching using nuclear magnetic resonance
According to the theoretical results, the quantum searching algorithm can be
generalized by replacing the Walsh-Hadamard(W-H) transform by almost any
quantum mechanical operation. We have implemented the generalized algorithm
using nuclear magnetic resonance techniques with a solution of chloroform
molecules. Experimental results show the good agreement between theory and
experiment.Comment: 11 pages,3 figure. Accepted by Phys. Rev. A. Scheduled Issue: 01 Mar
200
Grover Algorithm with zero theoretical failure rate
In standard Grover's algorithm for quantum searching, the probability of
finding the marked item is not exactly 1. In this Letter we present a modified
version of Grover's algorithm that searches a marked state with full successful
rate. The modification is done by replacing the phase inversion by two phase
rotation through angle . The rotation angle is given analytically to be
, where
, the number of items in the database, and
an integer equal to or greater than the integer part of . Upon measurement at -th iteration, the marked state
is obtained with certainty.Comment: 5 pages. Accepted for publication in Physical Review
Efficient Simulation of Quantum Systems by Quantum Computers
We show that the time evolution of the wave function of a quantum mechanical
many particle system can be implemented very efficiently on a quantum computer.
The computational cost of such a simulation is comparable to the cost of a
conventional simulation of the corresponding classical system. We then sketch
how results of interest, like the energy spectrum of a system, can be obtained.
We also indicate that ultimately the simulation of quantum field theory might
be possible on large quantum computers.
We want to demonstrate that in principle various interesting things can be
done. Actual applications will have to be worked out in detail also depending
on what kind of quantum computer may be available one day...Comment: 8 pages, latex, submitted to Phys. Rev. A, revised version has about
double length of original and contains new ideas, e.g. how to obtain the
spectrum of a quantum syste
Quantum computers can search rapidly by using almost any transformation
A quantum computer has a clear advantage over a classical computer for
exhaustive search. The quantum mechanical algorithm for exhaustive search was
originally derived by using subtle properties of a particular quantum
mechanical operation called the Walsh-Hadamard (W-H) transform. This paper
shows that this algorithm can be implemented by replacing the W-H transform by
almost any quantum mechanical operation. This leads to several new applications
where it improves the number of steps by a square-root. It also broadens the
scope for implementation since it demonstrates quantum mechanical algorithms
that can readily adapt to available technology.Comment: This paper is an adapted version of quant-ph/9711043. It has been
modified to make it more readable for physicists. 9 pages, postscrip
Lower Bounds of Quantum Search for Extreme Point
We show that Durr-Hoyer's quantum algorithm of searching for extreme point of
integer function can not be sped up for functions chosen randomly. Any other
algorithm acting in substantially shorter time gives incorrect
answer for the functions with the single point of maximum chosen randomly with
probability converging to 1. The lower bound as was
established for the quantum search for solution of equations where
is a Boolean function with such solutions chosen at random with probability
converging to 1.Comment: Some minor change
Quantum search algorithms on a regular lattice
Quantum algorithms for searching one or more marked items on a d-dimensional
lattice provide an extension of Grover's search algorithm including a spatial
component. We demonstrate that these lattice search algorithms can be viewed in
terms of the level dynamics near an avoided crossing of a one-parameter family
of quantum random walks. We give approximations for both the level-splitting at
the avoided crossing and the effectively two-dimensional subspace of the full
Hilbert space spanning the level crossing. This makes it possible to give the
leading order behaviour for the search time and the localisation probability in
the limit of large lattice size including the leading order coefficients. For
d=2 and d=3, these coefficients are calculated explicitly. Closed form
expressions are given for higher dimensions
Information and Accountants in the Role of Strategic Planning
This article on strategic planning practices is based upon a field study of five world-class companies. The strategic planning practices discussed in this article were extracted from the corporate environment. The information contained in this article, however, is of value alike to CPAs assisting with the enhancement of strategic planning practices in corporations and public accounting firms
Your EQ Skills: Got What it Takes?
Your EQ skills: got what it takes? So you thought the CPA exam was your last test? Read on.
Question: Is success in life and career determined primarily by rational intelligence (the IQ or intelligence quotient) or emotional intelligence (the EQ or emotional quotient)? In other words, what\u27s more important: intelligence or intuition? Historically the professional accounting literature has placed little emphasis on behavioral issues such as EQ, although human behavior underlies most of what is written and taught about professional accounting. Now managers place increased value on behavioral skills that help people in the workplace. Look at this statistic: The productivity of one-third of American workers is measured by how they add value to information. Doesn\u27t that describe CPAs exactly? This article will examine the ways in which EQ is crucial to CPAs\u27 success and how they can cultivate EQ if they haven\u27t got a lot of it.
The AICPA and the Institute of Management Accountants recognize that emotional intelligence skills are critical for the success of the accounting profession. In CPA Vision 2011 and Beyond: Focus on the Horizon (www.cpavision.org), the AICPA identifies emotional ..
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