# Domain decomposition method for the *N*-body time-independent and time-dependent Schrödinger equations

## Abstract

This paper is devoted to the derivation of a pleasingly parallel Galerkin method for the time-independent *N*-body Schrödinger equation, and its time-dependent version modeling molecules subject to an external electric field (Bandrauk 1994; Bandrauk et al., J. Phys. B-Atom. Mol. Opt. Phys. **46**(15), 153001, 2013; Cohen-Tannoudji et al. 1992). In this goal, we develop a Schwarz waveform relaxation (SWR) domain decomposition method (DDM) for the *N*-body Schrödinger equation. In order to optimize the efficiency and accuracy of the overall algorithm, (i) we use mollifiers to regularize the singular potentials and to approximate the Schrödinger Hamiltonian, (ii) we select appropriate orbitals, and (iii) we carefully derive and approximate the SWR transmission conditions. Some low-dimensional numerical experiments are presented to illustrate the methodology.

## Keywords

*N*-body Schrödinger equation Domain decomposition method Mollifiers Parallel computing

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## Notes

### Acknowledgments

The author would like to thank Prof. C.R. Anderson (UCLA) for helpful discussions about mollifiers and grid-based methods for solving the *N*-body Schrödinger equation.

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