349 research outputs found
The Massive Kaluza-Klein Monopole
We construct the (bosonic) effective worldvolume action of an M-theory
Kaluza-Klein monopole in a background given by the bosonic sector of
eleven-dimensional massive supergravity, i.e. a "massive Kaluza-Klein
monopole". As a consistency check we show that the direct dimensional reduction
along the isometry direction of the Taub-NUT space leads to the massive
D-6-brane. We furthermore perform a double dimensional reduction in the
massless case and obtain the effective worldvolume action of a type IIA
Kaluza-Klein monopole.Comment: 16 pages, Latex, no figures, typos corrected, one reference adde
Wrapping rules (in) string theory
In this paper we show that the number of all 1/2-BPS branes in string theory
compactified on a torus can be derived by universal wrapping rules whose
formulation we present. These rules even apply to branes in less than ten
dimensions whose ten-dimensional origin is an exotic brane. In that case the
wrapping rules contain an additional combinatorial factor that is related to
the highest dimension in which the ten-dimensional exotic brane, after
compactification, can be realized as a standard brane. We show that the
wrapping rules also apply to cases with less supersymmetry. As a specific
example, we discuss the compactification of IIA/IIB string theory on
.Comment: 21 page
BPS Open Strings and A-D-E-singularities in F-theory on K3
We improve on a recently constructed graphical representation of the
supergravity 7-brane solution and apply this refined representation to re-study
the open string description of the A-D-E-singularities in F-theory on K3. A
noteworthy feature of the graphical representation is that it provides the
complete global branch cut structure of the 7-brane solution which plays an
important role in our analysis. We first identify those groups of branes which
when made to coincide lead to the A-D-E-gauge groups. We next show that there
is always a sufficient number of open BPS strings to account for all the
generators of the gauge group. However, as we will show, there is in general no
one-to-one relation between BPS strings and gauge group generators.
For the D_{n+4}- and E-singularities, in order to relate BPS strings with
gauge group generators, we make an SU(n+4), respectively SU(5) subgroup of the
D_{n+4}- and E-gauge groups manifest. We find that only for the D-series (and
for the standard A-series) this is sufficient to identify, in a one-to-one
manner, which BPS strings correspond to which gauge group generators.Comment: 37 pages, 15 figure
Three-Dimensional Extended Bargmann Supergravity
We show that three-dimensional General Relativity, augmented with two vector
fields, allows for a non-relativistic limit, different from the standard limit
leading to Newtonian gravity, that results into a well-defined action which is
of the Chern-Simons type. We show that this three-dimensional `Extended
Bargmann Gravity', after coupling to matter, leads to equations of motion
allowing a wider class of background geometries than the ones that one
encounters in Newtonian gravity. We give the supersymmetric generalization of
these results and point out an important application in the context of
calculating partition functions of non-relativistic field theories using
localization techniques.Comment: 6 pages, v2: typo's corrected, reference updated, accepted for
publication in Phys. Rev. Let
Defect Branes
We discuss some general properties of "defect branes", i.e. branes of
co-dimension two, in (toroidally compactified) IIA/IIB string theory. In
particular, we give a full classification of the supersymmetric defect branes
in dimensions 2 < D < 11 as well as their higher-dimensionalstring and M-theory
origin as branes and a set of "generalized" Kaluza-Klein monopoles. We point
out a relation between the generalized Kaluza-Klein monopole solutions and a
particular type of mixed-symmetry tensors. These mixed-symmetry tensors can be
defined at the linearized level as duals of the supergravity potentials that
describe propagating degrees of freedom. It is noted that the number of
supersymmetric defect branes is always twice the number of corresponding
central charges in the supersymmetry algebra.Comment: Latex2e paper, 28 pages, no figures. Footnote adde
Non-relativistic fields from arbitrary contracting backgrounds
We discuss a non-relativistic contraction of massive and massless field
theories minimally coupled to gravity. Using the non-relativistic limiting
procedure introduced in our previous work, we (re-)derive non-relativistic
field theories of massive and massless spins 0 to 3/2 coupled to torsionless
Newton-Cartan backgrounds. We elucidate the relativistic origin of the
Newton-Cartan central charge gauge field and explain its relation to
particle number conservation.Comment: 19 page
The Symmetries of the Carroll Superparticle
Motivated by recent applications of Carroll symmetries we investigate the
geometry of flat and curved (AdS) Carroll space and the symmetries of a
particle moving in such a space both in the bosonic as well as in the
supersymmetric case. In the bosonic case we find that the Carroll particle
possesses an infinite-dimensional symmetry which only in the flat case includes
dilatations. The duality between the Bargmann and Carroll algebra, relevant for
the flat case, does not extend to the curved case.
In the supersymmetric case we study the dynamics of the N=1 AdS Carroll
superparticle. Only in the flat limit we find that the action is invariant
under an infinite-dimensional symmetry that includes a supersymmetric extension
of the Lifshitz Carroll algebra with dynamical exponent z=0. We also discuss in
the flat case the extension to N=2 supersymmetry and show that the flat N=2
superparticle is equivalent to the (non-moving) N=1 superparticle and that
therefore it is not BPS unlike its Galilei counterpart. This is due to the fact
that in this case kappa-symmetry eliminates the linearized supersymmetry.
In an appendix we discuss the N=2 curved case in three dimensions only and
show that there are two N=2 theories that are physically different.Comment: 35 pages; v
Brane orbits
We complete the classification of half-supersymmetric branes in toroidally
compactified IIA/IIB string theory in terms of representations of the T-duality
group. As a by-product we derive a last wrapping rule for the space-filling
branes. We find examples of T-duality representations of branes in lower
dimensions, suggested by supergravity, of which none of the component branes
follow from the reduction of any brane in ten-dimensional IIA/IIB string
theory. We discuss the constraints on the charges of half-supersymmetric
branes, determining the corresponding T-duality and U-duality orbits.Comment: 34 pages, 3 figure
Newton-Cartan supergravity with torsion and Schr\"odinger supergravity
We derive a torsionfull version of three-dimensional N=2 Newton-Cartan
supergravity using a non-relativistic notion of the superconformal tensor
calculus. The "superconformal" theory that we start with is Schr\"odinger
supergravity which we obtain by gauging the Schr\"odinger superalgebra. We
present two non-relativistic N=2 matter multiplets that can be used as
compensators in the superconformal calculus. They lead to two different
off-shell formulations which, in analogy with the relativistic case, we call
"old minimal" and "new minimal" Newton-Cartan supergravity. We find
similarities but also point out some differences with respect to the
relativistic case.Comment: 30 page
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