Marie-Am'elie Lawn

The Lebrun--Salamon conjecture is true in dimension up to 56

We prove the LeBrun--Salamon conjecture for positive quaternionic K\"ahler manifolds of quaternionic dimension n<= 14. To do so, we first show that the isometry group Isom(M) of any minimal counterexample M has rank at most one, hence dimension at most three. On the other hand, we consider a characteristic number which...