11 research outputs found
Sigma-model soliton intersections from exceptional calibrations
A first-order `BPS' equation is obtained for 1/8 supersymmetric intersections
of soliton-membranes (lumps) of supersymmetric (4+1)-dimensional massless sigma
models, and a special non-singular solution is found that preserves 1/4
supersymmetry. For 4-dimensional hyper-K\"ahler target spaces () the BPS
equation is shown to be the low-energy limit of the equation for a
Cayley-calibrated 4-surface in \bE^4\times HK_4. Similar first-order
equations are found for stationary intersections of Q-lump-membranes of the
massive sigma model, but now generic solutions preserve either 1/8
supersymmetry or no supersymmetry, depending on the time orientation.Comment: 21 pages. Version 3: Minor corrections and one further reference:
version published in JHE
More on scattering of Chern-Simons vortices
I derive a general formalism for finding kinetic terms of the effective
Lagrangian for slowly moving Chern-Simons vortices. Deformations of fields
linear in velocities are taken into account. From the equations they must
satisfy I extract the kinetic term in the limit of coincident vortices. For
vortices passing one over the other there is locally the right-angle
scattering. The method is based on analysis of field equations instead of
action functional so it may be useful also for nonvariational equations in
nonrelativistic models of Condensed Matter Physics.Comment: discussion around Eq.(45) is generalised, one more condition for the
local right-angle scattering is adde
D-brane Solitons in Supersymmetric Sigma-Models
Massive D=4 N=2 supersymmetric sigma models typically admit domain wall
(Q-kink) solutions and string (Q-lump) solutions, both preserving 1/2
supersymmetry. We exhibit a new static 1/4 supersymmetric `kink-lump' solution
in which a string ends on a wall, and show that it has an effective realization
as a BIon of the D=4 super DBI-action. It is also shown to have a
time-dependent Q-kink-lump generalization which reduces to the Q-lump in a
limit corresponding to infinite BI magnetic field. All these 1/4 supersymmetric
sigma-model solitons are shown to be realized in M-theory as calibrated, or
`Q-calibrated', M5-branes in an M-monopole background.Comment: 16 pages, 3 figures, Late
More on the Tensorial Central Charges in N=1 Supersymmetric Gauge Theories (BPS Wall Junctions and Strings)
We study the central extensions of the N=1 superalgebras relevant to the
soliton solutions with the axial geometry - strings, wall junctions, etc. A
general expression valid in any four-dimensional gauge theory is obtained. We
prove that the only gauge theory admitting BPS strings at weak coupling is
supersymmetric electrodynamics with the Fayet-Iliopoulos term. The problem of
ambiguity of the (1/2,1/2) central charge in the generalized Wess-Zumino models
and gauge theories with matter is addressed and solved. A possibility of
existence of the BPS strings at strong coupling in N=2 theories is discussed. A
representation of different strings within the brane picture is presented.Comment: 26 pages, 2 figures, 1 reference added, typos corrected, Sec. 9.3
expanded. Final version accepted for publication in Phys.Rev.
First and Second Order Vortex Dynamics
The low energy dynamics of vortices in selfdual Abelian Higgs theory is of
second order in vortex velocity and characterized by the moduli space metric.
When Chern-Simons term with small coefficient is added to the theory, we show
that a term linear in vortex velocity appears and can be consistently added to
the second order expression. We provides an additional check of the first and
second order terms by studying the angular momentum in the field theory. We
briefly explore other first order term due to small background electric charge
density and also the harmonic potential well for vortices given by the moment
of inertia.Comment: a rev tex file, 22 pages, no figur
Solitons and moduli spaces
SIGLEAvailable from British Library Document Supply Centre- DSC:D59842 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Skyrmions in flat space and curved space
SIGLEAvailable from British Library Document Supply Centre- DSC:9106.16(DAMTP--86-6) / BLDSC - British Library Document Supply CentreGBUnited Kingdo