Abstract
We generalize the Korkin-Zolotarev theorem to the case of entire functions having the smallest L1 norm on a system of intervals E. If C{set minus}E is a domain of Widom type with the Direct Cauchy Theorem, we give an explicit formula for the minimal deviation. Important relations between the problem and the theory of canonical systems with reflectionless resolvent functions are shown.
Original language | English |
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Pages (from-to) | 63-93 |
Number of pages | 31 |
Journal | Journal of Approximation Theory |
Volume | 179 |
DOIs | |
State | Published - Feb 2014 |
Externally published | Yes |
Bibliographical note
Funding Information:The author was supported by the Austrian Science Fund FWF , project no: P22025-N18.
Funding
The author was supported by the Austrian Science Fund FWF , project no: P22025-N18.
Funders | Funder number |
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Austrian Science Fund FWF | P22025-N18 |
Keywords
- Approximation by entire functions
- Canonical systems
- De Branges spaces
- Korkin-Zolotarev theorem
- Martin function
- Spectral theory
- Widom domains