Sasaki-Einstein 7-Manifolds, Orlik Polynomials and Homology

Abstract

Let $L_f$ be a link of an isolated hypersurface singularity defined by a weighted homogenous polynomial $f.$ In this article, we give ten examples of $2$-connected seven dimensional Sasaki-Einstein manifolds $L_f$ for which $H_3(L_f,\mathbb{Z})$ is completely determined. Using the Boyer-Galicki construction of links $L_f$ over particular Kähler-Einstein orbifolds, we apply a valid case of Orlik's conjecture to the links $L_f$ so that one is able to explicitly determine $H_3(L_f,\mathbb{Z}).$ We give ten such new examples, all of which have the third Betti number satisfy $10\le b_3(L_f)\le 20$.