Abstract
A description of the number N(K) of eigenvalues less than K for a pseudo-differential operator with positive symbol is given in terms of the number of unit cubes canonically imbedded in the subset of phase space where the symbol is less than CK. This gives back in particular the order of magnitude of N(K) for elliptic symbols.
Keywords: uncertainty principle, canonical transformations, packings of unit cubes
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Selected References
These references are in PubMed. This may not be the complete list of references from this article.
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