Entropy Functions with 5D Chern-Simons terms

In this note we reconsider Sen's entropy function analysis for 5D supergravity actions containing Chern-Simons terms. The apparent lack of gauge invariance is usually tackled via a 4D reduction. Here we motivate how a systematic 5D procedure also works. In doing so, it becomes important to identify the correct 5D charges. In particular, we perform explicit calculations for the black ring and 5D black hole. In the black ring analysis, we find Chern-Simons induced spectral flow shifts emerging out of Sen's formalism. We find that the entropy function nevertheless remains gauge invariant and the resulting electric charges are identified as Page charges. For the black hole too, 5D gauge invariance is confirmed. Our 5D analysis enables us to fix a mismatch that arose in the electric charges of Goldstein and Jena's 4D-reduced calculation. Finally we provide an interpretation for the e^0 - p^0 exchange in the entropy function as an interpolation between black hole and black ring geometries in Taub-NUT.Comment: 27 page

Near the horizon of 5D black rings

For the five dimensional N=2 black rings, we study the supersymmetry enhancement and identify the global supergroup of the near horizon geometry. We show that the global part of the supergroup is OSp(4*|2)X U(1) which is similar to the small black string. We show that results obtained by applying the entropy function formalism, the c-extremization approach and the Brown-Henneaux method to the black ring solution are in agreement with the microscopic entropy calculation.Comment: 26 pages, version to appear in JHEP, the near horizon superalgebra is corrected, discussion on small black ring is discarded, Brown-Henneaux approach to large black ring is adde

More rings to rule them all: Fragmentation, 4D ↔ 5D and split-spectral flows

In this note we set-up an explicit 5D construction of AdS-fragmentation, whereby a single black ring splits-up into a multi-black ring configuration. Furthermore it is seen that these fragmented rings are equivalent to a direct 5D lift of 4D multi-center black holes. Along the way we also determine the 4D/5D transformations relevant for multi-center charges. It is seen that the physical charges involved in black ring fragmentation are Page charges arising due to 5D Chern-Simons terms. As an application of these methods, we reproduce the total angular momentum of concentric black rings, originally due to Gauntlett and Gutowski. Finally we provide a geometric interpretation of fragmented black rings using the idea of split-spectral flows, which seeks to study charge shifts of a given black ring due to fluxes generated in a multi-ring background

Advanced interfaces to stem the data deluge in mixed reality: Placing human (un)consciousness in the loop

We live in an era of data deluge and this requires novel tools to effectively extract, analyze and understand the massive amounts of data produced by the study of natural and artificial phenomena in many areas of research