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BPS States and Automorphisms

Jordi Molins·Joan Simon
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Abstract

The purpose of the present paper is twofold. In the first part, we provide an algebraic characterization of several families of $ν= \frac{1}{2^n}$ $n\leq 5$ BPS states in M theory, at threshold and non-threshold, by an analysis of the BPS bound derived from the ${\cal N}=1$ D=11 SuperPoincaré algebra. We determine their BPS masses and their supersymmetry projection conditions, explicitly. In the second part, we develop an algebraic formulation to study the way BPS states transform under $GL(32,\bR)$ transformations, the group of automorphisms of the corresponding SuperPoincaré algebra. We prove that all $ν={1/2}$ non-threshold bound states are SO(32) related with $ν={1/2}$ BPS states at threshold having the same mass. We provide further examples of this phenomena for less supersymmetric $ν={1/4},{1/8}$ non-threshold bound states.

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Jordi Molins, Joan Simon. 2001-02-11. BPS States and Automorphisms. https://doi.org/10.1103/physrevd.62.125019

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