Compressed Resolvents, Q-functions and h0-resolvents in Almost Pontryagin Spaces

  • Henk de Snoo
  • Harald Woracek
Part of the Operator Theory: Advances and Applications book series (OT, volume 263)


The interest of this paper lies in the selfadjoint extensions of a symmetric relation in an almost Pontryagin space. More in particular, in their compressed resolvents, Q-functions and h0-resolvents. We give a systematic approach to each of this three topics, and show an intimate connection between the last two.


Almost Pontryagin space symmetric relation selfadjoint extension compressed resolvent Q-function h0-resolvent 

Mathematics Subject Classification (2010)

47B50 47B25 47A20 46C20 


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We thank Samuel Mohr for carefully reading a preliminary version of the manuscript and valuable comments.


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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  1. 1.Johann Bernoulli Institute for Mathematics and Computer ScienceUniversity of GroningenGroningenThe Netherlands
  2. 2.Institute ford Analysis and Scientific ComputingVienna University of TechnologyWienAustria

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