17 research outputs found
Large rotating AdS black holes from fluid mechanics
We use the AdS/CFT correspondence to argue that large rotating black holes in
global AdS(D) spaces are dual to stationary solutions of the relativistic
Navier-Stokes equations on S**(D-2). Reading off the equation of state of this
fluid from the thermodynamics of non-rotating black holes, we proceed to
construct the nonlinear spinning solutions of fluid mechanics that are dual to
rotating black holes. In all known examples, the thermodynamics and the local
stress tensor of our solutions are in precise agreement with the thermodynamics
and boundary stress tensor of the spinning black holes. Our fluid dynamical
description applies to large non-extremal black holes as well as a class of
large non-supersymmetric extremal black holes, but is never valid for
supersymmetric black holes. Our results yield predictions for the
thermodynamics of all large black holes in all theories of gravity on AdS
spaces, for example, string theory on AdS(5) x S**5 and M theory on AdS(4) x
S**7 and AdS(7) x S**4.Comment: 62 pages, 1 figure. v2: references, typo
Supersymmetric states of N = 4 Yang-Mills from giant gravitons
Mikhailov has constructed an infinite family of (1/8) BPS D3-branes in AdS5 × S5. We regulate Mikhailov's solution space by focussing on finite dimensional submanifolds. Our submanifolds are topologically complex projective spaces with symplectic form cohomologically equal to 2π N times the Fubini-Study Kahler class. Upon quantization and removing the regulator we find the Hilbert Space of N noninteracting Bose particles in a 3d Harmonic oscillator, a result previously conjectured by Beasley. This Hilbert Space is isomorphic to the classical chiral ring of (1/8) BPS states in N = 4 Yang-Mills theory. We view our result as evidence that the spectrum of (1/8) BPS states in N = 4 Yang Mills theory, which is known to jump discontinuously from zero to infinitesimal coupling, receives no further renormalization at finite values of the 't Hooft coupling
Two Alternating Motor Programs Drive Navigation in Drosophila Larva
When placed on a temperature gradient, a Drosophila larva navigates away from excessive cold or heat by regulating the size, frequency, and direction of reorientation maneuvers between successive periods of forward movement. Forward movement is driven by peristalsis waves that travel from tail to head. During each reorientation maneuver, the larva pauses and sweeps its head from side to side until it picks a new direction for forward movement. Here, we characterized the motor programs that underlie the initiation, execution, and completion of reorientation maneuvers by measuring body segment dynamics of freely moving larvae with fluorescent muscle fibers as they were exposed to temporal changes in temperature. We find that reorientation maneuvers are characterized by highly stereotyped spatiotemporal patterns of segment dynamics. Reorientation maneuvers are initiated with head sweeping movement driven by asymmetric contraction of a portion of anterior body segments. The larva attains a new direction for forward movement after head sweeping movement by using peristalsis waves that gradually push posterior body segments out of alignment with the tail (i.e., the previous direction of forward movement) into alignment with the head. Thus, reorientation maneuvers during thermotaxis are carried out by two alternating motor programs: (1) peristalsis for driving forward movement and (2) asymmetric contraction of anterior body segments for driving head sweeping movement
Plasmarings as dual black rings
We construct solutions to the relativistic Navier-Stokes equations that
describe the long wavelength collective dynamics of the deconfined plasma phase
of N=4 Yang Mills theory compactified down to d=3 on a Scherk-Schwarz circle
and higher dimensional generalisations. Our solutions are stationary, axially
symmetric spinning balls and rings of plasma. These solutions, which are dual
to (yet to be constructed) rotating black holes and black rings in
Scherk-Schwarz compactified AdS(5) and AdS(6), and have properties that are
qualitatively similar to those of black holes and black rings in flat five
dimensional supergravity.Comment: 40 pages, 40 figures. (v2) Correction to black brane equation of
state, additional reference
Lumps of plasma in arbitrary dimensions
We use the AdS/CFT correspondence in a regime in which the field theory
reduces to fluid dynamics to construct an infinite class of new black objects
in Scherk-Schwarz compactified AdS(d+2) space. Our configurations are dual to
black objects that generalize black rings and have horizon topology S^(d-n) x
T^n, for n less than or equal to (d-1)/2. Locally our fluid configurations are
plasma sheets that curve around into tori whose radii are large compared to the
thickness of the sheets (the ratio of these radii constitutes a small parameter
that permits the perturbative construction of these configurations). These
toroidal configurations are stabilized by angular momentum. We study solutions
whose dual horizon topologies are S^3 x S^1, S^4 x S^1 and S^3 x T^2 in detail;
in particular we investigate the thermodynamic properties of these objects. We
also present a formal general construction of the most general stationary
configuration of fluids with boundaries that solve the d-dimensional
relativistic Navier-Stokes equation.Comment: 32 pages, 10 figures; v2: Some figures are modified and a few
references added