Dear Physics Forum,(adsbygoogle = window.adsbygoogle || []).push({});

I think I am confused in applying the correspondence principle in QM, using the particle in a box and de Broglie wavelength calculations for massive (macroscopic) objects.

Why is the calculated energy of a massive object so small in the particle in a box

E = h^{2}/8mL^{2}

but when the de Broglie wavelength of a massive object is calculated,

λ = h/p

it is very small, meaning its frequency and so energy are high?

And if the energy level spacing is always n^{2}, why is it said that the spacing becomes continuous, not discrete, for massive objects?

Thanks for your help, Mark

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# Is the de Broglie wavelenght incongruent with particle in a box calculation?

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