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A variational method from the variance of energy

Luca Marotta·Fabio Siringo
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Abstract

A variational method is studied based on the minimum of energy variance. The method is tested on exactly soluble problems in quantum mechanics, and is shown to be a useful tool whenever the properties of states are more relevant than the eigenvalues. In quantum field theory the method provides a consistent second order extension of the gaussian effective potential.

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Luca Marotta, Fabio Siringo. 2005-06-28. A variational method from the variance of energy. https://doi.org/10.1140/epjc%2Fs2005-02358-x

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