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arXiv · 1607.01743

BPS states in the Minahan-Nemeschansky E6 theory

Lotte Hollands·Andrew Neitzke
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Abstract

We use the method of spectral networks to compute BPS state degeneracies in the Minahan-Nemeschansky $E_6$ theory, on its Coulomb branch, without turning on a mass deformation. The BPS multiplicities come out in representations of the $E_6$ flavor symmetry. For example, along the simplest ray in electromagnetic charge space, we give the first $14$ numerical degeneracies, and the first $7$ degeneracies as representations of $E_6$. We find a complicated spectrum, exhibiting exponential growth of multiplicities as a function of the electromagnetic charge. There is one unexpected outcome: the spectrum is consistent (in a nontrivial way) with the hypothesis of "spin purity," that if a BPS state in this theory has electromagnetic charge equal to $n$ times a primitive charge, then it appears in a spin-$\frac{n}{2}$ multiplet.

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Lotte Hollands, Andrew Neitzke. 2016-07-06. BPS states in the Minahan-Nemeschansky E6 theory. https://doi.org/10.1007/s00220-016-2798-1

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