On the structure of the intersection of real flag manifolds in a complex flag manifold

2019 ◽  
Author(s):  
Hiroshi Iriyeh ◽  
Takashi Sakai ◽  
Hiroyuki Tasaki
Keyword(s):  
Flag Manifold ◽  
Flag Manifolds ◽  
Complex Flag

scholarly journals Families of(1,2)-symplectic metrics on full flag manifolds

2002 ◽  
Vol 29 (11) ◽  
pp. 651-664 ◽  
Author(s):  
Marlio Paredes
Keyword(s):  
Flag Manifolds ◽  
Invariant Metrics ◽  
Complex Structures ◽  
Symplectic Invariant ◽  
Almost Complex Structures ◽  
Almost Complex ◽  
Complex Flag ◽  
Complex Flag Manifolds

We obtain new families of(1,2)-symplectic invariant metrics on the full complex flag manifoldsF(n). Forn≥5, we characterizen−3differentn-dimensional families of(1,2)-symplectic invariant metrics onF(n). Each of these families corresponds to a different class of nonintegrable invariant almost complex structures onF(n).

INVERSIONS IN CLASSICAL WEYL GROUPS

2007 ◽  
Vol 09 (01) ◽  
pp. 1-20
Author(s):  
KEQUAN DING ◽  
SIYE WU
Keyword(s):  
Finite Group ◽  
Weyl Group ◽  
Root Systems ◽  
Flag Manifold ◽  
Length Function ◽  
Weyl Groups ◽  
Flag Manifolds ◽  
A Finite Group

We introduce inversions for classical Weyl group elements and relate them, by counting, to the length function, root systems and Schubert cells in flag manifolds. Special inversions are those that only change signs in the Weyl groups of types Bn, Cnand Dn. Their counting is related to the (only) generator of the Weyl group that changes signs, to the corresponding roots, and to a special subvariety in the flag manifold fixed by a finite group.

scholarly journals Differential operators on quantized flag manifolds at roots of unity, II

2014 ◽  
Vol 214 ◽  
pp. 1-52
Author(s):  
Toshiyuki Tanisaki
Keyword(s):  
Differential Operators ◽  
Flag Manifold ◽  
Flag Manifolds ◽  
Roots Of Unity ◽  
Central Character ◽  
Derived Equivalence ◽  
Bernstein Type ◽  
Enveloping Algebra ◽  
Quantized Enveloping Algebra ◽  
Category Of Modules

AbstractWe formulate a Beilinson-Bernstein-type derived equivalence for a quantized enveloping algebra at a root of 1 as a conjecture. It says that there exists a derived equivalence between the category of modules over a quantized enveloping algebra at a root of 1 with fixed regular Harish-Chandra central character and the category of certain twistedD-modules on the corresponding quantized flag manifold. We show that the proof is reduced to a statement about the (derived) global sections of the ring of differential operators on the quantized flag manifold. We also give a reformulation of the conjecture in terms of the (derived) induction functor.

scholarly journals A geometric proof of an equivariant Pieri rule for flag manifolds

2019 ◽  
Vol 31 (3) ◽  
pp. 779-783
Author(s):  
Changzheng Li ◽  
Vijay Ravikumar ◽  
Frank Sottile ◽  
Mingzhi Yang
Keyword(s):  
Short Proof ◽  
Flag Manifold ◽  
Flag Manifolds ◽  
Algebraic Proof ◽  
Geometric Proof

Abstract We use geometry to give a short proof of an equivariant Pieri rule in the classical flag manifold. This rule is due to Robinson, who gave an algebraic proof.

scholarly journals HOMOGENEOUS EINSTEIN METRICS ON GENERALIZED FLAG MANIFOLDS WITH FIVE ISOTROPY SUMMANDS

2013 ◽  
Vol 24 (10) ◽  
pp. 1350077 ◽  
Author(s):  
ANDREAS ARVANITOYEORGOS ◽  
IOANNIS CHRYSIKOS ◽  
YUSUKE SAKANE
Keyword(s):  
Einstein Equation ◽  
Einstein Metrics ◽  
Flag Manifold ◽  
Polynomial Systems ◽  
Flag Manifolds ◽  
Isotropy Representation ◽  
Generalized Flag Manifolds ◽  
A New Technique ◽  
Kähler Einstein Metrics ◽  
Homogeneous Einstein Metrics

We construct the homogeneous Einstein equation for generalized flag manifolds G/K of a compact simple Lie group G whose isotropy representation decomposes into five inequivalent irreducible Ad (K)-submodules. To this end, we apply a new technique which is based on a fibration of a flag manifold over another such space and the theory of Riemannian submersions. We classify all generalized flag manifolds with five isotropy summands, and we use Gröbner bases to study the corresponding polynomial systems for the Einstein equation. For the generalized flag manifolds E6/(SU(4) × SU(2) × U(1) × U(1)) and E7/(U(1) × U(6)) we find explicitly all invariant Einstein metrics up to isometry. For the generalized flag manifolds SO (2ℓ + 1)/( U (1) × U (p) × SO (2(ℓ - p - 1) + 1)) and SO (2ℓ)/( U (1) × U (p) × SO (2(ℓ - p - 1))) we prove existence of at least two non-Kähler–Einstein metrics. For small values of ℓ and p we give the precise number of invariant Einstein metrics.

scholarly journals Orbits of real forms in complex flag manifolds

2010 ◽  
pp. 69-109
Author(s):  
Altomani Andrea ◽  
Medori Costantino ◽  
Nacinovich Mauro
Keyword(s):  
Flag Manifolds ◽  
Complex Flag ◽  
Real Forms ◽  
Complex Flag Manifolds

scholarly journals Schur Times Schubert via the Fomin-Kirillov Algebra

10.37236/3659 ◽  
2014 ◽  
Vol 21 (1) ◽  
Author(s):  
Karola Mészáros ◽  
Greta Panova ◽  
Alexander Postnikov
Keyword(s):  
Cohomology Ring ◽  
Quantum Cohomology ◽  
Flag Manifold ◽  
Combinatorial Proof ◽  
Schubert Polynomial ◽  
Schubert Polynomials ◽  
Small Quantum ◽  
Special Cases ◽  
Expansion Coefficients ◽  
Complex Flag

We study multiplication of any Schubert polynomial $\mathfrak{S}_w$ by a Schur polynomial $s_{\lambda}$ (the Schubert polynomial of a Grassmannian permutation) and the expansion of this product in the ring of Schubert polynomials. We derive explicit nonnegative combinatorial expressions for the expansion coefficients for certain special partitions $\lambda$, including hooks and the $2\times 2$ box. We also prove combinatorially the existence of such nonnegative expansion when the Young diagram of $\lambda$ is a hook plus a box at the $(2,2)$ corner. We achieve this by evaluating Schubert polynomials at the Dunkl elements of the Fomin-Kirillov algebra and proving special cases of the nonnegativity conjecture of Fomin and Kirillov.This approach works in the more general setup of the (small) quantum cohomology ring of the complex flag manifold and the corresponding (3-point) Gromov-Witten invariants. We provide an algebro-combinatorial proof of the nonnegativity of the Gromov-Witten invariants in these cases, and present combinatorial expressions for these coefficients.

Sign in / Sign up

Export Citation Format

Share Document