Decorated and augmented nonlinear Grassmannians can be used to parametrize coadjoint orbits of classical diffeomorphism groups. We provide a general framework for decoration and augmentation functors that facilitates the construction of a smooth structure on decorated or augmented nonlinear Grassmannians. This permits to equip the corresponding coadjoint orbits with the structure of a smooth symplectic Fréchet manifold. The coadjoint orbits obtained in this way are not new. Here, we provide a uniform description of their smooth structures.
@article{JOLT_2025_35_4_a5,
author = {Stefan Haller and Cornelia Vizman},
title = {Nonlinear {Grassmannians:} {Plain,} {Decorated,} {Augmented}},
journal = {Journal of Lie Theory},
pages = {805--843},
year = {2025},
volume = {35},
number = {4},
url = {http://geodesic.mathdoc.fr/item/JOLT_2025_35_4_a5/}
}
TY - JOUR
AU - Stefan Haller
AU - Cornelia Vizman
TI - Nonlinear Grassmannians: Plain, Decorated, Augmented
JO - Journal of Lie Theory
PY - 2025
SP - 805
EP - 843
VL - 35
IS - 4
UR - http://geodesic.mathdoc.fr/item/JOLT_2025_35_4_a5/
ID - JOLT_2025_35_4_a5
ER -