# Convergence of Scaled Delta Expansion: Anharmonic Oscillator

@article{Guida1995ConvergenceOS, title={Convergence of Scaled Delta Expansion: Anharmonic Oscillator}, author={R. Guida and K. Konishi and Hiroshi Suzuki}, journal={Annals of Physics}, year={1995}, volume={241}, pages={152-184} }

Abstract We prove that the linear delta expansion for energy eigenvalues of the quantum mechanical anharmonic oscillator converges to the exact answer if the order dependent trial frequency Ω is chosen to scale with the order as Ω = CNγ; 1/3 0 as N → ∞. It converges also for γ = 1/3, if C ≥ αcg1/3, αc ≃ 0.570875, where g is the coupling constant in front of the operator q4/4. The extreme case with γ = 1/3, C = γcg1/3 corresponds to the choice discussed earlier by Seznec and Zinn-Justin and… Expand

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