16,694 research outputs found
Lifshitz and Schrodinger Vacua, Superstar Resolution in Gauged Maximal Supergravities
We consider the subset of gauged maximal supergravities that consists of the
SO(n+1) gauge fields A^{ij} and the scalar deformation T^{ij} of the S^n in the
spherical reduction of M-theory or type IIB. We focus on the Abelian Cartan
subgroup and the diagonal entries of T^{ij}. The resulting theories can be
viewed as the STU models with additional hyperscalars. We find that the
theories with only one or two such vectors can be generalized naturally to
arbitrary dimensions. The same is true for the D=4 or 5 Einstein-Maxwell theory
with such a hyperscalar. The gauge fields become massive, determined by
stationary points of the hyperscalars a la the analogous Abelian Higgs
mechanism. We obtain classes of Lifshitz and Schrodinger vacua in these
theories. The scaling exponent z turns out to be rather restricted, taking
fractional or irrational numbers. Tweaking the theories by relaxing the mass
parameter or making a small change of the superpotential, we find that
solutions with z=2 can emerge. In a different application, we find that the
resolution of superstar singularity in the STU models by using bubbling-AdS
solitons can be generalized to arbitrary dimensions in our theories. In
particular, we obtain the smooth AdS solitons that can be viewed as the
resolution of the Reissner-Nordstrom superstars in general dimensions.Comment: Latex, 24 page
Thermodynamics of Lifshitz Black Holes
We specialize the Wald formalism to derive the thermodynamical first law for
static black holes with spherical/torus/hyperbolic symmetries in a variety of
supergravities or supergravity-inspired theories involving multiple scalars and
vectors. We apply the formula to study the first law of a general class of
Lifshitz black holes. We analyse the first law of three exact Lifshitz black
holes and the results fit the general pattern. In one example, the first law is
where are the electric potential and charge of the
Maxwell field. The unusual vanishing of mass in this specific solution
demonstrates that super-extremal charged black holes can exist in asymptotic
Lifshitz spacetimes.Comment: 27 page
Experimental implementation of generalized Grover's algorithm of multiple marked states and its application
Generalized Grover's searching algorithm for the case in which there are
multiple marked states is demonstrated on a nuclear magnetic resonance (NMR)
quantum computer. The entangled basis states (EPR states) are synthesized using
the algorithm.Comment: 20 pages,3 figure
Scalar Charges in Asymptotic AdS Geometries
We show that for n-dimensional Einstein gravity coupled to a scalar field
with mass-squared m_0^2=-n(n-2)/(4\ell^2), the first law of thermodynamics of
(charged) AdS black holes will be modified by the boundary conditions of the
scalar field at asymptotic infinity. Such scalars can arise in gauged
supergravities in four and six dimensions, but not in five or seven. The result
provides a guiding principle for constructing designer black holes and solitons
in general dimensions, where the properties of the dual field theories depend
on the boundary conditions.Comment: Latex, 9 pages, references adde
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