Abstract
We use level sets to give a counter-example to a conjecture of J. Borcea and B. Shapiro. In particular we show that there are real polynomials P such that there is a chord of the level set Im P'(z)=P(z) = 0 that does not have a non-real zero of P lying on it. In addition, we use level sets to show that there are no bounded components of the set {z: Im z > 0 and ImQ(z) > 0} where Q = z -f/f" and f is a real entire function.
Original language | English (US) |
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Pages (from-to) | 1-12 |
Number of pages | 12 |
Journal | Computational Methods and Function Theory |
Volume | 11 |
Issue number | 1 |
DOIs | |
State | Published - 2011 |
Keywords
- Hawai'i Conjecture
- Level sets
- Real polynomials
- Zeros
ASJC Scopus subject areas
- Analysis
- Computational Theory and Mathematics
- Applied Mathematics