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A New Concept for the Momentum of a Quantum Mechanical Particle in a Box

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 نشر من قبل Uwe-Jens Wiese R.C.
 تاريخ النشر 2020
  مجال البحث فيزياء
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For a particle in a box, the operator $- i partial_x$ is not Hermitean. We provide an alternative construction of a momentum operator $p = p_R + i p_I$, which has a Hermitean component $p_R$ that can be extended to a self-adjoint operator, as well as an anti-Hermitean component $i p_I$. This leads to a description of momentum measurements performed on a particle that is strictly limited to the interior of a box.



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