Improvement of the Envelope Theory for Systems with Different Particles
- URL: http://arxiv.org/abs/2111.14744v2
- Date: Thu, 31 Mar 2022 07:08:52 GMT
- Title: Improvement of the Envelope Theory for Systems with Different Particles
- Authors: Cyrille Chevalier, Cintia T. Willemyns, Lorenzo Cimino, Claude Semay
- Abstract summary: The envelope theory is a method to compute approximate eigensolutions of quantum $N$-body Hamiltonians.
It is possible to improve the precision of the eigenvalues by combining the envelope theory with a generalisation to $N$-body of the dominantly orbital state method.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: The envelope theory is a method to compute approximate eigensolutions of
quantum $N$-body Hamiltonians with a quite general structure in $D$ dimensions.
The advantages of the method are that it is easy to implement and that $N$ is
treated as any other parameters of the Hamiltonian, allowing the computation
for systems of all sizes. If solutions are reliable, they are generally not
very accurate. In the case of systems with identical particles for $D \ge 2$,
it is possible to improve the precision of the eigenvalues by combining the
envelope theory with a generalisation to $N$-body of the dominantly orbital
state method. It is shown that a similar improvement can be achieved in the
case of systems composed of identical particles plus a different one. The
quality of the new procedure is tested with different systems.
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