42 research outputs found
D1 and D5-brane giant gravitons on
We construct various examples of 1/4-BPS giant gravitons embedded into the
type IIB supergravity background with pure R-R flux: two D1-brane giants wrapping 1-cycles in
and , and one D5-brane giant wrapping a
4-cycle in and the . These D-branes are
supported by angular momenta P on one 3-sphere and P on
the other. We then construct a general class of 1/8-BPS D5-brane giant
gravitons wrapping 4-cycles in and the
. Here is the intersection of a holomorphic surface
in with the
submanifold. The holomorphic surface
is defined by , with
and the complex coordinates. There is
supersymmetry enhancement to 1/4-BPS in the special case of
which our original D5-brane giant graviton is an example.Comment: 30 pages, 4 figures. reference and figure added, minor change
Integrable open spin-chains in AdS3/CFT2 correspondences
We study integrable open boundary conditions for d(2,1;\alpha)^2 and
psu(1,1|2)^2 spin-chains. Magnon excitations of these open spin-chains are
mapped to massive excitations of type IIB open superstrings ending on D-branes
in the AdS_3 x S^3 x S^3 x S^1 and AdS_3 x S^3 x T^4 supergravity geometries
with pure R-R flux. We derive reflection matrix solutions of the boundary
Yang-Baxter equation which intertwine representations of a variety of boundary
coideal subalgebras of the bulk Hopf superalgebra. Many of these integrable
boundaries are matched to D1- and D5-brane maximal giant gravitons.Comment: v1: 61 pages, 6 figures; v2: minor changes and reference added; v3:
minor changes, 60 pages, version accepted to journa
A giant graviton genealogy
In this article we extend the construction of giant gravitons from
holomorphic surfaces [arXiv:hep-th/0010206] to the ABJM correspondence. We
construct a new class of 1/6-BPS M5-branes wrapping 5-manifolds in S^7/Z_k and
supported by a large angular momentum in the orbifold space. These orbifold
giant gravitons undergo a supersymmetry enhancement to 1/3-BPS and 1/2-BPS
configurations in special cases. The compactification of M-theory on AdS_4 x
S^7/Z_k to type IIA superstring theory on AdS_4 x CP^3 then gives rise to
another new class of 1/6-BPS D4 and NS5-branes wrapping 4 and 5-manifolds in
CP^3. The D4-branes carry a combination of D0-brane charge and angular momentum
in the complex projective space, while the NS5-branes are supported only by
D0-brane charge. Finally, we present a detailed analysis of a one-parameter
family of 1/2-BPS M5-brane orbifold giant gravitons, and their D4 and NS5-brane
CP^3 descendants.Comment: 34 pages; 1 figure; minor revisions; references adde
Meromorphic Functions and the Topology of Giant Gravitons
Using Mikhailov's map from holomorphic functions to supersymmetric D3-brane
solutions, we show how to construct giant gravitons in AdS5 x S5 with toroidal
topologies. In the 1/4-BPS sector we show that these are always of the form #^K
(S2 x S1), and in the limit in which this becomes a set of m+n perpendicular
spherical giants re-connected near to their intersections, we find K in terms
of m,n. In the 1/8-BPS sector we find a similar class of solutions.Comment: 10 pages, 8 figure
S^2 x S^3 geometries in ABJM and giant gravitons
We construct a new NS5-brane solution in AdS_4 x CP^3 with S^2 x S^3
topology. This solution belongs to the general class of non-Einstein N_{11}
metrics to which T^{1,1} belongs, and carries a non-vanishing D0-brane charge.
In eleven dimensions it gives rise to a squashed S^2 x S^3 M5-brane giant
graviton which is now of the N_{10} type. The energies of both solutions
satisfy the BPS bound E=kQ/2, indicating supersymmetric configurations, where Q
is interpreted as D0-brane charge for the NS5-brane and as angular momentum for
the dynamically stable M5-brane giant graviton. The ground state is degenerate
with a spherical D2 or M2-brane, rather than with a point-like object.
Moreover, while the charge of the spherical 2-brane can be arbitrary, the
charge of the S^2 x S^3 5-brane is bounded by N/2, with N the rank of the ABJM
gauge group, a manifestation of the stringy exclusion principle. A microscopic
description, suitable for the study of the finite 't Hooft coupling region, is
provided in terms of spherical D2 or M2-branes expanding into fuzzy 3-spheres.Comment: 30 pages; 2 figures; change to JHEP3 style; minor revision
Susceptibility and synergism profiles of multi-drug resistant pseudomonas aeruginusa in an intensive care environment
Please read the abstract in the front section of this documentDissertation (MSc (Medical Microbiology))--University of Pretoria, 2005.Medical Microbiologyunrestricte
ADS/CFT correspondence in a non-supersymmetric Yi-deformed background
A non-supersymmetric
Yi-deformed AdS/CFT correspondence has recently been conjectured
by Frolov. A detailed description of both sides of this proposed gauge/string
duality is presented. The analogy that exists between single trace gauge theory operators
in the SU(3) sector and
i-deformed SU(3) integrable spin chains is also
discussed. Frolov, Roiban and Tseytlin’s leading order comparison between the
ideformed
spin chain coherent state action and
i-deformed string worldsheet action
in the semiclassical limit is reviewed. A particular Lax pair representation for the
first order semiclassical
i-deformed spin chain/string action is then constructed
Cancer diagnoses profile of bone marrow specimens from November 2012 to December 2015 in a tertiary academic setting
This study aimed to examine the number and type of cancer diagnoses made based on bone marrow aspirates (BMA) using morphology
and/or histology, over a three year period. All the data collected (2012-2015) was obtained using the Trak-Care laboratory
information system (LIS) of the National Health Laboratory Service (NHLS). Data was categorised into four categories including
acute leukaemias (ALs), chronic leukaemias (CLs), Hodgkin’s lymphoma (HL), Non-Hodgkin’s lymphoma (NHL) and a miscellaneous
group.
The laboratory test most frequently used to make diagnoses was bone marrow aspiration (BMA) morphology (199), followed by
flow cytometry (138), histology (113), fluorescent in situ hybridisation (FISH) (54) and polymerase chain reaction (PCR) (9). In total,
the top three conditions diagnosed were acute myeloid leukaemias (AMLs), chronic myeloid leukaemia (CML) and B-cell acute
lymphoblastic leukaemia (B-ALL). There was good agreement between the diagnoses made by BMA morphology, BMT histology
and flow cytometry.
Results showed that BMA morphology was the most popular diagnostic test used and that this test had excellent agreement with
BMT histology and flow cytometry diagnoses. The most frequently diagnosed conditions were the AMLs.http://www.smltsa.org.za/publications.htmlam2018Haematolog