A MODIFIED BOGOLIUBOV METHOD APPLIED TO A SIMPLE BOSON MODEL

abstract

• 2017, Pleiades Publishing, Ltd. We use a non-gauge-invariant modification of the exact Hamiltonian to obtain a new Hamiltonian-like operator for a simple exactly solvable boson model. The eigenvalues of the new operator are close to those of the original Hamiltonian. We make a one-body approximation of the new two-body operator in the spirit of the Bogoliubov approximation. Because only the number operator appears, the c-number approximation is not required individually for the creation or annihilation operators in the ground state. For the simple model, the results using the new approximation are closer to the exact results than the usual Bogoliubov results over a wide range of parameters. The improvement increases dramatically as the model interaction strength increases.

authors

• Bassichis, William

published proceedings

• THEORETICAL AND MATHEMATICAL PHYSICS

author list (cited authors)

• Litt, O., & Bassichis, W. H.

citation count

• 0

complete list of authors

• Litt, O||Bassichis, WH

publication date

• January 2017

publisher

• Pleiades Publishing  Publisher

published in

• Theoretical and Mathematical Physics  Journal

keywords

• Modified Bogoliubov Approximation

Digital Object Identifier (DOI)

• 10.1134/S0040577917010093

start page

• 109

end page

• 119

volume

• 190

issue

• 1

URL

• http://dx.doi.org/10.1134/s0040577917010093