A method of approximation of discrete Schr\"odinger equation with the
normalized Laplacian by discrete-time quantum walk on graphs
- URL: http://arxiv.org/abs/2308.13741v1
- Date: Sat, 26 Aug 2023 02:57:47 GMT
- Title: A method of approximation of discrete Schr\"odinger equation with the
normalized Laplacian by discrete-time quantum walk on graphs
- Authors: Kei Saito, Etsuo Segawa
- Abstract summary: We propose a class of continuous-time quantum walk models on graphs induced by a certain class of discrete-time quantum walk models.
The induced continuous-time quantum walk is an extended version of the (free) discrete-Schr"odinger equation driven by the normalized Laplacian.
We show that each discrete-time quantum walk with an appropriate setting of the parameter $epsilon$ in the long time limit identifies with its induced continuous-time quantum walk.
- Score: 0.10878040851637999
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We propose a class of continuous-time quantum walk models on graphs induced
by a certain class of discrete-time quantum walk models with the parameter
$\epsilon\in [0,1]$. Here the graph treated in this paper can be applied both
finite and infinite cases. The induced continuous-time quantum walk is an
extended version of the (free) discrete-Schr\"odinger equation driven by the
normalized Laplacian: the element of the weighted Hermitian takes not only a
scalar value but also a matrix value depending on the underlying discrete-time
quantum walk. We show that each discrete-time quantum walk with an appropriate
setting of the parameter $\epsilon$ in the long time limit identifies with its
induced continuous-time quantum walk and give the running time for the
discrete-time to approximate the induced continuous-time quantum walk with a
small error $\delta$. We also investigate the detailed spectral information on
the induced continuous-time quantum walk.
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