20 research outputs found
Quantum walk on distinguishable non-interacting many-particles and indistinguishable two-particle
We present an investigation of many-particle quantum walks in systems of
non-interacting distinguishable particles. Along with a redistribution of the
many-particle density profile we show that the collective evolution of the
many-particle system resembles the single-particle quantum walk evolution when
the number of steps is greater than the number of particles in the system. For
non-uniform initial states we show that the quantum walks can be effectively
used to separate the basis states of the particle in position space and
grouping like state together. We also discuss a two-particle quantum walk on a
two- dimensional lattice and demonstrate an evolution leading to the
localization of both particles at the center of the lattice. Finally we discuss
the outcome of a quantum walk of two indistinguishable particles interacting at
some point during the evolution.Comment: 8 pages, 7 figures, To appear in special issue: "quantum walks" to be
published in Quantum Information Processin
The Benefits and Costs of Noise Reduction
This paper attempts to measure, in a cost-benefit analysis, a stricter noise abatement programme for noise originating from roads in Israel. Using the hedonic price method for three large cities and rural area transactions, a benefit from noise reduction was found. In order to perform a social cost-benefit analysis, a measure of benefit has been derived for 1 km of road and has been compared with the cost of noise reduction under different types of road structure. The results indicate that even though benefits have largely increased when compared to past decades (e.g. 1.2% of an average urban property value per 1 decibel reduction), the decision to insulate a given road is dependent on location and road structure. This raises the normative question of a national vs. regional standard that decision makers should be aware of and such studies could be of help in this respect.