• Corpus ID: 243847847

Unitary group orbits versus groupoid orbits of normal operators

@inproceedings{Belti2021UnitaryGO,
  title={Unitary group orbits versus groupoid orbits of normal operators},
  author={Daniel Beltiţă and Gabriel Larotonda},
  year={2021}
}
We study the unitary orbit of a normal operator a ∈ B(H), regarded as a homogeneous space for the action of unitary groups associated with symmetrically normed ideals of compact operators. We show with an unified treatment that the orbit is a submanifold of the differing ambient spaces if and only if the spectrum of a is finite, and in that case it is a closed submanifold. For arithmetically mean closed ideals, we show that nevertheless the orbit always has a natural manifold structure, modeled… 

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