## Local and global $$\sigma$$-cone porosity.(English)Zbl 0816.46014

Summary: We compare two subclasses of first category sets in Hilbert spaces, one of $$\sigma-\alpha$$-cone porous and the other of $$\sigma- \alpha$$-angle porous sets. Our Theorem gives a positive result whence an example shows that these two notions do not coincide.

### MSC:

 46C05 Hilbert and pre-Hilbert spaces: geometry and topology (including spaces with semidefinite inner product)
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