Lifting 1/4-BPS States on K3 and Mathieu Moonshine
High Energy Physics - Theory
2020-08-07 v2 Algebraic Geometry
Number Theory
Representation Theory
Abstract
The elliptic genus of K3 is an index for the 1/4-BPS states of its sigma model. At the torus orbifold point there is an accidental degeneracy of such states. We blow up the orbifold fixed points using conformal perturbation theory, and find that this fully lifts the accidental degeneracy of the 1/4-BPS states with h=1. At a generic point near the Kummer surface the elliptic genus thus measures not just their index, but counts the actual number of these BPS states. We comment on the implication of this for symmetry surfing and Mathieu moonshine.
Keywords
Cite
@article{arxiv.1905.00035,
title = {Lifting 1/4-BPS States on K3 and Mathieu Moonshine},
author = {Christoph A. Keller and Ida G. Zadeh},
journal= {arXiv preprint arXiv:1905.00035},
year = {2020}
}
Comments
29+5 pp, a sign mistake corrected in eqs. (3.14) and (4.20), footnote 6 added to clarify this point, references added