16 research outputs found

### M2-M5 Systems in N=6 Chern-Simons Theory

We study two aspects of M5-branes in N=6 U(N)xU(N) Chern-Simons gauge theory.
We first examine multiple M2-branes ending on a M5-brane. We study Basu-Harvey
type cubic equations, fuzzy funnel configurations, and derive the M5-brane
tension from the N=6 theory. We also find a limit in which the above M2-M5
system reduces to a D2-D4 system and we recover the Nahm equation from the N=6
theory. We then examine domain wall configurations in mass-deformed N=6 theory
with a manifest SU(2)xSU(2)xU(1) global symmetry. We derive tensions of domain
walls connecting between arbitrary M5-brane vacua of the deformed theory and
observe their consistency with gravity dual expectations.Comment: 15 pages, Latex. v2: typos fixed, reference added. v3: Journal
version in JHE

### Light Gauginos and Conformal Sequestering

In a wide class of direct and semi-direct gauge mediation models, it has been
observed that the gaugino masses vanish at leading order. It implies that there
is a hierarchy between the gaugino and sfermion masses, invoking a fine-tuning
problem in the Higgs sector via radiative corrections. In this paper, we
explore the possibility of solving this anomalously light gaugino problem
exploiting strong conformal dynamics in the hidden sector. With a mild
assumption on the anomalous dimensions of the hidden sector operators, we show
that the next to leading order contributions to the gaugino masses can
naturally be in the same order as the sfermion masses. \mu/B_\mu problem is
also discussed.Comment: 17 pages, 1 figure. References adde

### Five-Dimensional Gauged Supergravity with Higher Derivatives.

This thesis summarizes the recent developments on the study of five-dimensional
gauged supergravity with higher derivative terms, emphasizing in particular the ap-
plication to understanding the hydrodynamic properties of gauge theory plasma via
the AdS/CFT correspondence. We first review how the ungauged and gauged five-
dimensional supergravity actions with higher derivative terms can be constructed
using the off-shell superconformal formalism. Then we relate the gauged supergrav-
ity to four-dimensional gauge theory using the AdS/CFT correspondence and extract
the physical quantities associated with gauge theory plasma from the dual classical
supergravity computations. We put a particular emphasis on the discussion of the
conjectured lower bound for the shear viscosity over entropy density ratio proposed
by Kovtun, Son and Starinets, and discuss how higher derivative terms in supergrav-
ity and the introduction of chemical potential for the R-charge affect this bound.PHDPhysicsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/93983/1/hanaki_1.pd

### Temporal Analysis of Language through Neural Language Models

We provide a method for automatically detecting change in language across
time through a chronologically trained neural language model. We train the
model on the Google Books Ngram corpus to obtain word vector representations
specific to each year, and identify words that have changed significantly from
1900 to 2009. The model identifies words such as "cell" and "gay" as having
changed during that time period. The model simultaneously identifies the
specific years during which such words underwent change

### Black holes in five-dimensional gauged supergravity with higher derivatives

We examine five-dimensional $\mathcal N=2$ gauged supergravity including
terms up to four derivatives. These additional terms correspond to the
supersymmetric completion of $R^2$, and were originally obtained in
hep-th/0611329 using conformal supergravity techniques. Here we integrate out
the auxiliary fields and obtain the on-shell action for minimal supergravity
with such corrections. We then construct $R$-charged AdS black holes to linear
order in the four derivative terms and investigate the effect of these
corrections on their thermodynamical properties. Finally, we relate the
geometrical coefficients governing the four-derivative corrections to gauge
theory data using holographic anomaly matching. This enables us to obtain a
microscopic expression for the entropy of the solutions.Comment: 34 pages. Typos fixed, some comments and references adde

### Higher derivative effects on eta/s at finite chemical potential

We examine the effects of higher derivative corrections on eta/s, the ratio
of shear viscosity to entropy density, in the case of a finite R-charge
chemical potential. In particular, we work in the framework of five-dimensional
N =2 gauged supergravity, and include terms up to four derivatives,
representing the supersymmetric completion of the Chern-Simons term A \wedge Tr
(R \wedge R). The addition of the four-derivative terms yields a correction
which is a 1/N effect, and in general gives rise to a violation of the eta/s
bound. Furthermore, we find that, once the bound is violated, turning on the
chemical potential only leads to an even larger violation of the bound.Comment: Typos fixed, references and comments on conventions adde

### Comments on Charges and Near-Horizon Data of Black Rings

We study how the charges of the black rings measured at the asymptotic
infinity are encoded in the near-horizon metric and gauge potentials,
independent of the detailed structure of the connecting region. Our analysis
clarifies how different sets of four-dimensional charges can be assigned to a
single five-dimensional object under the Kaluza-Klein reduction. Possible
choices are related by the Witten effect on dyons and by the large gauge
transformation in four and five dimensions, respectively.Comment: 30 pages, 1 figure; v2: additional references; v3: published versio

### Symmetries of Holographic Super-Minimal Models

We compute the asymptotic symmetry of the higher-spin supergravity theory in
AdS_3 and obtain an infinite-dimensional non-linear superalgebra, which we call
the super-W_infinity[lambda] algebra. According to the recently proposed
supersymmetric duality between higher-spin supergravity in an AdS_3 background
and the 't Hooft limit of the N=2 CP^n Kazama-Suzuki model on the boundary,
this symmetry algebra should agree with the 't Hooft limit of the chiral
algebra of the CFT, SW_n. We provide two nontrivial checks of the duality. By
comparing the algebras, we explicitly match the lowest-spin commutation
relations in the super-W_infinity[lambda] with the corresponding commutation
relations in the 't Hooft limit on the CFT side. We also consider the
degenerate representations of the two algebras and find that the spectra of the
chiral primary fields are identical.Comment: 33 pages, references added, some errors corrected, discussions about
the truncation of the shs[lambda] algebra and reobtaining the original
shs[lambda] algebra from the super-W_infinity[lambda] algebra adde