Ten Problems in Hilbert

نویسنده

  • P. R. HALMOS
چکیده

PREFACE 1. CONVERGENT. Does the set of cyclic operators have a non-empty interior?... 2. WEIGHTED. Is every part of a weighted shift similar to a weighted shift?. . . . 3. INVARIANT. If an intransitive operator has an inverse, is its inverse also intransitive? 4. TRIANGULAR. Is every normal operator the sum of a diagonal operator and a compact one? 5. DILATED. Is every subnormal Toeplitz operator either analytic or normal?... 6. SIMILAR. Is every polynomially bounded operator similar to a contraction?.. 7. NILPOTENT. IS every quasinilpotent operator the norm limit of nilpotent ones? 8. REDUCIBLE. Is every operator the norm limit of reducible ones? 9. REFLEXIVE. Is every complete Boolean algebra reflexive? 10. TRANSITIVE. IS every non-trivial strongly closed transitive atomic lattice either medial or self-conjugate? BIBLIOGRAPHY

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تاریخ انتشار 2007