3 papers
math.DG2026
Rigidity of compact four-dimensional weakly Einstein Ricci Solitons
JeongHyeong Park, Wooseok Shin
We prove that every compact four-dimensional weakly Einstein Ricci soliton is Einstein. The nontrivial compact case reduces to the gradient shrinking setting, where a differential…
math.DG2025
Weakly Einstein conformal products
Andrzej Derdzinski, JeongHyeong Park, Wooseok Shin
One says that a Riemannian four-manifold is \emph{weakly Einstein} if the three-index contraction of its curvature tensor against itself equals a function times the metric. Since t…
math.DG2025
Weakly Einstein curvature tensors
Andrzej Derdzinski, JeongHyeong Park, Wooseok Shin
We classify weakly Einstein algebraic curvature tensors in an oriented Euclidean 4-space, defined by requiring that the three-index contraction of the curvature tensor against itse…