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arXiv · 1304.0307

On two classes of perturbations: Role of signs of second-order Rayleigh-Schr\"odinger energy corrections

Kamal Bhattacharyya
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Abstract

We distinguish two extreme classes of perturbation problems depending on the signs of second-order energy corrections and argue why it is generally much more probable to obtain a negative value of the same for any state in the standard Rayleigh-Schr\"odinger perturbation theory. The classes are seen to differ in reproducing results of finite-dimensional matrix perturbations. A few related issues are also discussed, some of which are based on available analytical results.

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Kamal Bhattacharyya. 2013-04-01. On two classes of perturbations: Role of signs of second-order Rayleigh-Schr\"odinger energy corrections. https://arxiv.org/abs/1304.0307

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