3 papers
math.SG2026
On the common index jump theorem and further developments
Huagui Duan, Yiming Long, Wei Wang +1
In [LZ02] published in Annals of Mathematics, Long and Zhu established originally the common index jump theorem (CIJT) for symplectic paths in 2002, which has played an important r…
math.FA2025
Gaps and relative dimensions
Chenfeng Liao, Chaofeng Zhu
In this paper, the notion of semi-compact perturbation of a closed linear subspace is introduced. Then for a of pair of closed linear subspace of a Banach space such that one is a…
math.FA2025
Skew-adjoint linear relatioins between Banach spaces
Hanchen Li, Chaofeng Zhu
In this paper, we prove the stability theorems for the isotropic perturbations of maximal isotropic subspaces in symplectic Banach spaces. Then we prove a stability theorem for the…