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H. Sati

Publications and source records attributed to H. Sati.

7 recordsLinked to original sources
arXiv2006

Flux Compactifications on Projective Spaces and The S-Duality Puzzle

We derive a formula for D3-brane charge on a compact spacetime, which includes torsion corrections to the tadpole cancellation condition. We use this to classify D-branes and RR fluxes in type II string theory on RP^3xRP^{2k+1}xS^{6-2k} with torsion H-flux and to demonstrate the conjectured T-duality to S^3xS^{2k+1}xS^{6-2k} with no flux. When k=1, H\neq 0 and so the K-theory that classifies fluxes is twisted. When k=2 the square of the H-flux yields an S-dual Freed-Witten anomaly which is canceled by a D3-brane insertion that ruins the K-theory classification. When k=3 the cube of H is nontrivial and so the D3 insertion may itself be inconsistent and the compactification unphysical. Along the way we provide a physical interpretation for the AHSS in terms of boundaries of branes within branes.

hep-th↗
arXiv2004

Complementarity of the Maldacena and Karch-Randall Pictures

We perform a one-loop test of the holographic interpretation of the Karch-Randall model, whereby a massive graviton appears on an AdS_4 brane in an AdS_5 bulk. Within the AdS/CFT framework, we examine the quantum corrections to the graviton propagator on the brane, and demonstrate that they induce a graviton mass in exact agreement with the Karch-Randall result. Interestingly enough, at one loop order, the spin 0, spin 1/2 and spin 1 loops contribute to the dynamically generated (mass)^2 in the same 1: 3: 12 ratio as enters the Weyl anomaly and the 1/r^3 corrections to the Newtonian gravitational potential.

hep-th↗
arXiv2002

Quantum Discontinuity for Massive Spin 3/2 with a Lambda Term

We show that the recently demonstrated absence of the van Dam-Veltman-Zakharov discontinuity for massive spin 3/2 with a Lambda term is an artifact of the tree level approximation, and that the discontinuity reappears at one loop. As a numerical check on the calculation, we rederive the vanishing of the one- loop beta function for D=11 supergravity on AdS_4 x S^7 level-by-level in the Kaluza-Klein tower.

hep-th↗
arXiv2001

Quantum M^2 -> 2Lambda/3 discontinuity for massive gravity with a Lambda term

In a previous paper we showed that the absence of the van Dam-Veltman-Zakharov discontinuity as M^2 -> 0 for massive spin-2 with a Lambda term is an artifact of the tree approximation, and that the discontinuity reappears at one loop, as a result of going from five degrees of freedom to two. In this paper we show that a similar classical continuity but quantum discontinuity arises in the "partially massless" limit M^2 -> 2Lambda/3, as a result of going from five degrees of freedom to four.

hep-th↗
arXiv2000

Breathing mode compactifications and supersymmetry of the brane-world

It has recently been shown that the Randall-Sundrum brane-world may be obtained from an appropriate doubled D3-brane configuration in type IIB theory. This corresponds, in five dimensions, to a sphere compactification of the original IIB theory with a non-trivial breathing mode supporting the brane. In this paper, we shall study the supersymmetry of this reduction to massive five-dimensional supergravity, and derive the effective supersymmetry transformations for the fermionic superpartners to the breathing mode. We also consider the sphere compactifications of eleven-dimensional supergravity to both four and seven dimensions. For the compactifications on S^5 and S^7, we include a squashing mode scalar and discuss the truncation from N=8 to N=2 supersymmetry.

hep-th↗
arXiv1999

Embedding AdS Black Holes in Ten and Eleven Dimensions

We construct the non-linear Kaluza-Klein ansätze describing the embeddings of the U(1)^3, U(1)^4 and U(1)^2 truncations of D=5, D=4 and D=7 gauged supergravities into the type IIB string and M-theory. These enable one to oxidise any associated lower dimensional solutions to D=10 or D=11. In particular, we use these general ansätze to embed the charged AdS_5, AdS_4 and AdS_7 black hole solutions in ten and eleven dimensions. The charges for the black holes with toroidal horizons may be interpreted as the angular momenta of D3-branes, M2-branes and M5-branes spinning in the tranverse dimensions, in their near-horizon decoupling limits. The horizons of the black holes coincide with the worldvolumes of the branes. The Kaluza-Klein ansätze also allow the black holes with spherical or hyperbolic horizons to be reinterpreted in D=10 or D=11.

hep-th↗