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A Congruence Modulo Four for Real Schubert Calculus with Isotropic Flags

Published online by Cambridge University Press:  20 November 2018

Nickolas Hein ,
Frank Sottile  and
Igor Zelenko
Nickolas Hein
Affiliation:
Department of Mathematics and Computer Science, Benedictine College, Atchison, Kansas 66002, USA. nhein@benedictine.edu
Frank Sottile
Affiliation:
Department of Mathematics, Texas A&M University, College Station, Texas 77843, USA. sottile@math.tamu.edu, zelenko@math.tamu.edu
Igor Zelenko
Affiliation:
Department of Mathematics, Texas A&M University, College Station, Texas 77843, USA. sottile@math.tamu.edu, zelenko@math.tamu.edu
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Abstract

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We previously obtained a congruence modulo four for the number of real solutions to many Schubert problems on a square Grassmannian given by osculating flags. Here we consider Schubert problems given by more general isotropic flags, and prove this congruence modulo four for the largest class of Schubert problems that could be expected to exhibit this congruence.

Keywords

14N1514P99Lagrangian GrassmannianWronski mapShapiro Conjecture
Type
Research Article
Information
Canadian Mathematical Bulletin , Volume 60 , Issue 2 , 01 June 2017 , pp. 309 - 318
Copyright
Copyright © Canadian Mathematical Society 2017

References

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