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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
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.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2017

References

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