An effective theory for higher-dimensional black holes and applications to metastable antibranes

Abstract

Despite their consequential applications across the subfields of high energy physics, metastable states of antibranes in warped throats are not yet fully understood. In this thesis, we provide new information on various aspects of these metastable antibranes through applications of the blackfold effective theory for higher-dimensional black holes. As concrete examples, we study the conjectured metastable state of polarised anti-D3 branes (namely, wrapped NS5 branes with dissolved D3 brane charge) at the tip of the Klebanov-Strassler (KS) throat in type IIB supergravity and the analogous state of polarised anti-M2 branes (namely, wrapped M5 branes with dissolved M2 brane charge) at the tip of the Cvetic-Gibbons-Lu-Pope (CGLP) throat in eleven-dimensional supergravity.


For anti-D3 branes in KS throat, from a finite-temperature analysis in the wrapped NS5 regime, we provide novel evidence for the existence of the metastable state exactly where no-go theorems are lifted. In particular, in the extremal limit, we recover directly in supergravity the metastable states originally discovered by Kachru, Pearson, and Verlinde (KPV). Away from extremality, we uncover a metastable wrapped black NS5 state (the thermalised version of the KPV state) and observe that such metastability is lost when we heat the wrapped NS5 state sufficiently that its horizon geometry resembles that of a black anti-D3 state.



All claims regarding metastability of antibranes in warped throats only refer to a balance of force and not statements of robustness under perturbations. For their various applications, it is important to determine whether these configurations are truly metastable by probing them with perturbations. Here, we study the classical stability of the KPV state under generic long-wavelength deformations. We observe that, with regards to considered perturbations and regime of parameters, the state is classically stable.


A study of anti-M2 branes in CGLP throat reveals many similarities to that of the anti-D3 branes. We recover directly in supergravity the Klebanov-Pufu (KP) state at extremality, and our finite temperature results fit suggestively well with known, complementary no-go theorems. However, a unique feature of the anti-M2 state is that when considering the effects of non-zero temperature on the KP metastable state, we discover an exotic pattern of thermal transitions different from that of the KPV.


This thesis contains detailed discussions on all the above results as well as a pedagogical introduction to the blackfold formalism, focusing on aspects immediately relevant to applications to metastable antibranes.