22,389 research outputs found
Explicit Construction of Spin 4 Casimir Operator in the Coset Model
We generalize the Goddard-Kent-Olive (GKO) coset construction to the
dimension 5/2 operator for and compute the fourth order
Casimir invariant in the coset model with the generic unitary minimal
series that can be viewed as perturbations of the
limit, which has been investigated previously in the realization of
free fermion model.Comment: 11 page
Non-Subelliptic estimates for the tangential Cauchy-Riemann system
We prove non-subelliptic estimates for the tangential Cauchy-Riemann system
over a weakly "-pseudoconvex" higher codimensional submanifold of
\C^n. Let us point out that our hypotheses do not suffice to guarantee
subelliptic estimates, in general. Even more: hypoellipticity of the tangential
C-R system is not in question (as shows the example by Kohn in case of a
Levi-flat hypersurface). However our estimates suffice for existence of smooth
solutions to the inhomogeneous C-R equations in certain degree.
The main ingredients in our proofs are the weighted estimates by
H\"ormander and Kohn and the tangential -Neumann operator by
Kohn. As for the notion of pseudoconvexity we follow closely Zampieri. The
main technical result is a version for "perturbed" -pseudoconvex domains of
a similar result by Ahn who generalizes in turn Chen-Shaw.Comment: 21 page
Perturbing Around A Warped Product Of AdS_4 and Seven-Ellipsoid
We compute the spin-2 Kaluza-Klein modes around a warped product of AdS_4 and
a seven-ellipsoid. This background with global G_2 symmetry is related to a
U(N) x U(N) N=1 superconformal Chern-Simons matter theory with sixth order
superpotential. The mass-squared in AdS_4 is quadratic in G_2 quantum number
and KK excitation number. We determine the dimensions of spin-2 operators using
the AdS/CFT correspondence. The connection to N=2 theory preserving SU(3) x
U(1)_R is also discussed.Comment: 21pp; The second and last paragraphs of section 2, the footnotes 1
and 2 added and to appear in JHE
Supersymmetric Reflection Matrices
We briefly review the general structure of integrable particle theories in
1+1 dimensions having N=1 supersymmetry. Examples are specific perturbed
superconformal field theories (of Yang-Lee type) and the N=1 supersymmetric
sine-Gordon theory. We comment on the modifications that are required when the
N=1 supersymmetry algebra contains non-trivial topological charges.Comment: 7 pages, Revtex, 2 figures, talk given at the International Seminar
on Supersymmetry and Quantum Field Theory, dedicated to the memory of
D.V.Volkov, Kharkov (Ukraine), January 5-7, 199
Spacelike boundaries from the c=1 Matrix Model
We find classical solutions of two dimensional noncritical string theory
which give rise to geometries with spacelike boundaries, similar to spacetimes
with cosmological event horizons. In the c=1 matrix model, these solutions have
a representation as simple time dependent configurations. We obtain the causal
structure of the resulting spacetimes. Using the macroscopic loop transform, we
probe the form of the tachyon condensate in the asymptotic regions.Comment: 22 pages, 5 figures, v2: reference added, v3: minor correction
More on Meta-Stable Brane Configuration
We describe the intersecting brane configuration of type IIA string theory
corresponding to the meta-stable nonsupersymmetric vacua in four dimensional
N=1 supersymmetric SU(N_c) gauge theory with an antisymmetric flavor, a
conjugate symmetric flavor, eight fundamental flavors, m_f fundamental flavors
and m_f antifundamental flavors. This is done by analyzing the N=1
supersymmetric SU(2m_f-N_c+4) magnetic gauge theory with dual matters and the
corresponding dual superpotential.Comment: 20 pp, 3 figures; Pages 11,12, and 14 improved; to appear in CQ
Temperature‐dependent transmission extended electron energy‐loss fine structure of aluminum
Inelastic electron scattering experiments in a transmission electron microscope provide a probe of core electron excitations that have binding energies below 2 keV, and that are localized within submicron diameter sample volumes. Extended electron energy‐loss fine‐structure measurements which show the variation with temperature of the mean squared relative displacement of aluminum yield a localized measurement of the Debye temperature which is in excellent agreement with macroscopic measurements
Giant planar Hall effect in colossal magnetoresistive La(0.84)Sr(0.16)MnO(3) thin films
The transverse resistivity in thin films of La(0.84)Sr(0.16)MnO(3)
(LSMO)exhibits sharp field-symmetric jumps below Tc. We show that a likely
source of this behavior is the giant planar Hall effect (GPHE) combined with
biaxial magnetic anisotropy. The effect is comparable in magnitude to that
observed recently in the magnetic semiconductor Ga(Mn)As. It can be potentially
used in applications such as magnetic sensors and non-volatile memory devices
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