6 papers
Einstein metrics, their moduli spaces and stability
Paul Schwahn, Uwe Semmelmann
This survey deals with two closely connected topics: first, the stability of Einstein metrics under the Einstein-Hilbert functional, and second, their deformation theory and the st…
The Standard Model Gauge Group from the Exceptional Jordan Algebra
John C. Baez, Paul Schwahn
We construct the Standard Model gauge group using the exceptional Jordan algebra and its automorphism group . The group acts o…
Geometries with parallel, skew-symmetric and closed torsion
Andrei Moroianu, Paul Schwahn
We study Riemannian manifolds carrying a metric connection with parallel, skew-symmetric and closed torsion, which we call in short PSCT manifolds. We prove that PSCT manifolds alw…
Balanced subsets in root systems
Andrei Moroianu, Paul Schwahn
Balanced and well-balanced subsets of the set of positive roots of compact Lie algebras arise naturally in problems related to Hermitian and spin geometry. In this paper we compute…
Formalizing a classification theorem for low-dimensional solvable Lie algebras in Lean
Viviana del Barco, Gustavo Infanti, Exequiel Rivas +1
We present a formalization, in the theorem prover Lean, of the classification of solvable Lie algebras of dimension at most three over arbitrary fields. Lie algebras are algebraic…
Sandwich operators and Einstein deformations of compact symmetric spaces related to Jordan algebras
Stuart James Hall, Paul Schwahn, Uwe Semmelmann
We study the deformability of the symmetric Einstein metrics on the spaces and , thereby concluding the problem to s…