J 2012

Flag manifolds, symmetric t-triples and Einstein metrics

CHRYSIKOS, Ioannis

Základní údaje

Originální název

Flag manifolds, symmetric t-triples and Einstein metrics

Vydání

Differential Geometry and its Applications, Elsevier, 2012, 0926-2245

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

10101 Pure mathematics

Stát vydavatele

Nizozemské království

Utajení

není předmětem státního či obchodního tajemství

Odkazy

Impakt faktor

Impact factor: 0.484

UT WoS

000313917800008

Klíčová slova anglicky

Generalized flag manifolds; t-Roots; Symmetric t-triples; Root systems; Structure constants; Homogeneous Einstein metrics

Štítky

Příznaky

Mezinárodní význam, Recenzováno
Změněno: 17. 4. 2024 09:29, Mgr. Marie Šípková, DiS.

Anotace

V originále

Let G be a compact connected simple Lie group and let M = G(C)/P = G/K be a generalized flag manifold. In this article we focus on an important invariant of G/K, the so-called t-root system R-t, and we introduce the notion of symmetric t-triples, that is triples of t-roots xi, zeta, eta is an element of R-t such that xi + eta + zeta = 0. We describe their properties and we present an interesting application on the structure constants of G/K, quantities which are straightforward related to the construction of the homogeneous Einstein metric on G/K. We classify symmetric t-triples for generalized flag manifolds G/K with second Betti number b(2)(G/K) = 1, and next we treat the case of full flag manifolds G/T, with b(2)(G/T)=l= rk G, where T is a maximal torus of G. In the last section we construct the homogeneous Einstein equation on flag manifolds G/K with five isotropy summands, determined by the simple Lie group G = SO(7). By solving the corresponding algebraic system we classify all SO(7)-invariant (non-isometric) Einstein metrics, and these are the very first results towards the classification of homogeneous Einstein metrics on flag manifolds with five isotropy summands.