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Bootstrap in Quantum Mechanical system

About the project

This repository follows the procedure from David Berenstein et al. - Bootstrapping Simple QM Systems. The detail mathematical derivation can be found in bootstrap_derivation.pdf, and the result will be discussed in bootstrap_result.pdf.


Installation

Since most of the code is written in Sympy, it is highly recommended to run with Jupyter Notebook or Jupyter Lab. The package we used is in requirements.txt.

python -m pip install -r requirements.txt

Algorithm

  1. Construct a class with specific potential, also contains functions to compute recursion relation and the determinant of sub-matrices.
  2. Find the interval for energy eigenvalues such that the Hankel Matrix is positive-semi definite. (Mainly processed by bootstrap_sympy.py)
  3. Plot the solved energy eigenvalues interval with different size of matrices.

Get started

To get a feeling how we do the Bootstrap Method, you can run bootstrap_numpy.ipynb, however the performance is restricted to due to the decimal precision.

Tha full main codes are written with ipynb, and run with sympy, select a specific potential and open the correspoding ipynb file.

  • harmonic_sympy.ipynb : bootstrapping with harmonic potential $V(x)=kx^2$

  • hydrogen_sympy.ipynb : bootstrapping with Coulomb potential $V(r)=-\frac{k}{r}$

  • harmonic_sympy.ipynb : bootstrapping with Yukawa potential $V(r)=-\frac{k}{r}e^{-ar}$, but approximated to first order

The computed result can be load from the correspoding directories (harmonic, hydrogen, yukawa_order1)