The 'most classical' states of Euclidean invariant elementary quantum
mechanical systems
- URL: http://arxiv.org/abs/2111.11876v2
- Date: Tue, 12 Jul 2022 18:54:35 GMT
- Title: The 'most classical' states of Euclidean invariant elementary quantum
mechanical systems
- Authors: L\'aszl\'o B Szabados
- Abstract summary: Complex techniques of general relativity are used to determine emphall the states in the two and three dimensional momentum spaces.
The existence of such states depends not only on the Lie algebra, but on the choice for its generators as well.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Complex techniques of general relativity are used to determine \emph{all} the
states in the two and three dimensional momentum spaces in which the equality
holds in the uncertainty relations for the non-commuting basic observables of
Euclidean invariant elementary quantum mechanical systems, even with non-zero
intrinsic spin. It is shown that while there is a 1-parameter family of such
states for any two components of the angular momentum vector operator with any
angle between them, such states exist for the component of the linear and the
angular momenta \emph{only if} these components are orthogonal to each other
and hence the problem is reduced to the two-dimensional Euclidean invariant
case. We also show that the analogous states exist for a component of the
linear momentum and of the centre-of-mass vector \emph{only if} the angle
between them is zero or an acute angle. \emph{No} such state (represented by a
square integrable and differentiable wave function) can exist for \emph{any}
pair of components of the centre-of-mass vector operator. Therefore, the
existence of such states depends not only on the Lie algebra, but on the choice
for its generators as well.
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