Derivation of 1st order correction to energy degenerate spec

Thread starter Imperatore
Start date Oct 13, 2015
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Correction Derivation Energy

In summary, the first order correction to energy is a term in perturbation theory used to account for small changes in the energy levels of a degenerate system. It is calculated by taking the inner product of the perturbation operator with the perturbed wavefunction and normalizing it. This correction is important in understanding and predicting the behavior of quantum systems, but it can also be applied to non-degenerate systems. However, its accuracy is limited to small perturbations and it assumes that the perturbation does not significantly change the wavefunction.

Oct 13, 2015

Imperatore

Hello there !

I need to derive the formula of first order correction to the energy in the case of discrete level of wave function with descrete spectrum.

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Oct 13, 2015

DrClaude

Mentor

Any decent textbook on QM should explain that.

What is the first order correction to energy for a degenerate system?

The first order correction to energy is a term in the perturbation theory that accounts for the small changes in the energy levels of a degenerate system due to a perturbation or disturbance.

How is the first order correction to energy calculated?

The first order correction to energy is calculated by taking the inner product of the perturbation operator with the perturbed wavefunction and then normalizing it by dividing it by the energy difference between the unperturbed and perturbed states.

What is the significance of the first order correction to energy?

The first order correction to energy allows us to account for small changes in the energy levels of a degenerate system, which is important in understanding and predicting the behavior of quantum systems.

Can the first order correction to energy be applied to non-degenerate systems?

Yes, the first order correction to energy can also be applied to non-degenerate systems but it is not as significant as it is for degenerate systems where the energy levels are closer together.

What are the limitations of using the first order correction to energy?

The first order correction to energy is only accurate for small perturbations and may not provide accurate results for larger perturbations. It also assumes that the perturbation is small enough to not cause any significant changes in the wavefunction.