2,283 research outputs found
Realization of Minimal Supergravity
Minimal supergravity mediation of supersymmetry breaking has attracted much
attention due to its simplicity, which leads to its predictive power. We
consider how Nature possibly realizes minimal supergravity through inflationary
selection of the theory. Minimality is impressively consistent with the present
observational bounds and it might be tested with the aid of low-energy soft
parameters obtained in future experiments.Comment: 18 pages, 5 figure
Solutions of deformed three-dimensional gravity
We investigate the gauging of a three-dimensional deformation of the anti-de
Sitter algebra, which accounts for the existence of an invariant energy scale.
By means of the Poisson sigma model formalism, we obtain explicit solutions of
the field equations, which reduce to the BTZ black hole in the undeformed
limit.Comment: 15 pages, LaTe
Warped Compactification with an Abelian Gauge Theory
We investigate warped compactification with an abelian gauge theory in six
dimensions. The vanishing cosmological constant in four dimensions can
generically be realized with a regular metric even in a 3-brane background
without fine tuning of couplings.Comment: 6 pages, late
Nonlinearly Realized Extended Supergravity
We provide nonlinear realization of supergravity with an arbitrary number of
supersymmetries by means of coset construction. The number of gravitino degrees
of freedom counts the number of supersymmetries, which will be possibly probed
in future experiments. We also consider goldstino embedding in the construction
to discuss the relation to nonlinear realization with rigid supersymmetries.Comment: 19 page
Warped Compactification with a Four-Brane
Warped compactification of the six-dimensional bulk with a negative
cosmological constant is realized with a 4-brane along with an abelian gauge
theory. No fine tuning of couplings are needed to obtain the vanishing
cosmological constant in four dimensions, as is the case for the bulk with a
positive cosmological constant.Comment: 6 pages, late
Thermal conductivity in B- and C- phase of UPt_3
Although the superconductivity in UPt_3 is one of the most well studied,
there are still lingering questions about the nodal directions in the B and C
phase in the presence of a magnetic field. Limiting ourselves to the low
temperature regime (T<<Delta(0)), we study the magnetothermal conductivity with
in semiclassical approximation using Volovik's approach. The angular dependence
of the magnetothermal conductivity for an arbitrary field direction should
clarify the nodal structure in UPt_3.Comment: 4 pages, 5 figure
Enhanced quasiparticle heat conduction of the multigap superconductor Lu2Fe3Si5
The thermal transport measurements have been made on the Fe-based
superconductor Lu2Fe3Si5 (Tc ~ 6 K) down to a very low temperature Tc/120. The
field and temperature dependences of the thermal conductivity confirm the
multigap superconductivity with fully opened gaps on the whole Fermi surfaces.
In comparison to MgB2 as a typical example of the multigap superconductor in a
p-electron system, Lu2Fe3Si5 reveals a remarkably enhanced quasiparticle heat
conduction in the mixed state. The results can be interpreted as a consequence
of the electronic correlations derived from Fe 3d-electrons.Comment: 5 pages, 4 figure
Thermoelectric response near a quantum critical point: the case of CeCoIn5
We present a study of thermoelectric coefficients in CeCoIn_5 down to 0.1 K
and up to 16 T in order to probe the thermoelectric signatures of quantum
criticality. In the vicinity of the field-induced quantum critical point, the
Nernst coefficient nu exhibits a dramatic enhancement without saturation down
to lowest measured temperature. The dimensionless ratio of Seebeck coefficient
to electronic specific heat shows a minimum at a temperature close to threshold
of the quasiparticle formation. Close to T_c(H), in the vortex-liquid state,
the Nernst coefficient behaves anomalously in puzzling contrast with other
superconductors and standard vortex dynamics.Comment: 4 pages, 4 figures,final published versio
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