Pieter Bomans, Davide Cassani, Giuseppe Dibitetto, Nicolò Petri
SciPost Phys. 12, 099 (2022) ·
published 18 March 2022

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We consider compactifications of massive IIA supergravity on a sixsphere. This setup is known to give rise to nonsupersymmetric AdS$_4$ vacua preserving SO$(7)$ as well as G$_2$ residual symmetry. Both solutions have a round $S^6$ metric and are supported by the Romans’ mass and internal $F_6$ flux. While the SO$(7)$ invariant vacuum is known to be perturbatively unstable, the G$_2$ invariant one has been found to have a fully stable KaluzaKlein spectrum. Moreover, it has been shown to be protected against branejet instabilities. Motivated by these results, we study possible bubbling solutions connected to the G$_2$ vacuum, representing nonperturbative instabilities of the latter. We indeed find an instability channel represented by the nucleation of a bubble of nothing dressed up with a homogeneous D2 brane charge distribution in the internal space. Our solution generalizes to the case where $S^6$ is replaced by any sixdimensional nearlyKähler manifold.
SciPost Phys. 11, 004 (2021) ·
published 9 July 2021

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The counting of BPS states in fourdimensional ${\cal N}=1$ theories has attracted a lot of attention in recent years. For superconformal theories, these states are in onetoone correspondence with local operators in various short representations. The generating function for this counting problem has branch cuts and hence several Cardylike limits, which are analogous to hightemperature limits. Particularly interesting is the second sheet, which has been shown to capture the microstates and phases of supersymmetric black holes in AdS$_5$. Here we present a 3d Effective Field Theory (EFT) approach to the hightemperature limit on the second sheet. We use the EFT to derive the behavior of the index at orders $\beta^{2},\beta^{1},\beta^0$. We also make a conjecture for $O(\beta)$, where we argue that the expansion truncates up to exponentially small corrections. An important point is the existence of vector multiplet zero modes, unaccompanied by massless matter fields. The runaway of AffleckHarveyWitten is however avoided by a nonperturbative confinement mechanism. This confinement mechanism guarantees that our results are robust.