Matrix Norms, BPS Bounds and Marginal Stability in N=8 Supergravity

Understand

We study the conditions of marginal stability for two-center extremal black holes in N-extended supergravity in four dimensions, with particular emphasis on the N=8 case.

• This is achieved by exploiting triangle inequalities satisfied by matrix norms.
• Using different norms and relative bounds among them, we establish the existence of marginal stability and split attractor flows both for BPS and some non-BPS solutions.
• Our results are in agreement with previous analysis based on explicit construction of multi-center solutions.