8 research outputs found
More on New Massive Gravity: Exact Solutions
We give a novel description of the recently proposed theory of new massive
gravity (NMG) in three dimensions. We show that in terms of a Dirac type
differential operator acting on the traceless Ricci tensor, the field equations
of the theory reduce to the massive Klein-Gordon type equation with a
curvature-squared source term and to a constraint equation. Under a certain
relation between the source tensor and the traceless Ricci tensor, fulfilled
for constant scalar curvature, the field equations of topologically massive
gravity (TMG) can be thought of as the "square-root" of the massive
Klein-Gordon type equation. Using this fact, we establish a simple framework
for mapping all known algebraic types D and N solutions of TMG into NMG. We
also present new exact solutions of algebraic types D and N which are only
inherent in NMG.Comment: 4 pages, twocolumn REVTeX; Minor cosmetic changes made and new metric
adde
Type N Spacetimes as Solutions of Extended New Massive Gravity
We study algebraic type N spacetimes in the extended new massive gravity
(NMG), considering both the Born-Infeld model (BI-NMG) and the model of NMG
with any finite order curvature corrections. We show that for these spacetimes,
the field equations of BI-NMG take the form of the massive (tensorial)
Klein-Gordon type equation, just as it happens for ordinary NMG. This fact
enables us to obtain the type N solution to BI-NMG, utilizing the general type
N solution of NMG, earlier found in our work. We also obtain type N solutions
to NMG with all finite order curvature corrections and show that, in contrast
to BI-NMG, this model admits the critical point solutions, which are
counterparts of "logarithmic" AdS pp-waves solutions of NMG.Comment: 6 pages, twocolumn REVTe
Uniqueness of Rotating Charged Black Holes in Five-Dimensional Minimal Gauged Supergravity
We study a five-dimensional spacetime admitting, in the presence of torsion,
a non-degenerate conformal Killing-Yano 2-form which is closed with respect to
both the usual exterior differentiation and the exterior differentiation with
torsion. Furthermore, assuming that the torsion is closed and co-closed with
respect to the exterior differentiation with torsion, we prove that such a
spacetime is the only spacetime given by the Chong-Cvetic-Lu-Pope solution for
stationary, rotating charged black holes with two independent angular momenta
in five-dimensional minimal gauged supergravity.Comment: Dedicated to Nihat Berker on the occasion of his 60th birthday; 13
pages, REVTe
Stationary Spinning Strings and Symmetries of Classical Spacetimes
We explore the symmetries of classical stationary spacetimes in terms of the
dynamics of a spinning string described by a worldsheet supersymmetric action.
We show that for stationary configurations of the string, the action reduces to
that for a pseudo-classical spinning point particle in an effective space,
which is a conformally scaled quotient space of the original spacetime. As an
example, we consider the stationary spinning string in the Kerr-Newman
spacetime, whose motion is equivalent to that of the spinning point particle in
the three-dimensional effective space. We present the Killing tensor as well as
the spin-valued Killing vector of this space. However, the nongeneric
supersymmetry corresponding to the Killing-Yano tensor of the Kerr-Newman
spacetime is lost in the effective space.Comment: 14 pages, REVTe
The General Type N Solution of New Massive Gravity
We find the most general algebraic type N solution with non-vanishing scalar
curvature, which comprises all type N solutions of new massive gravity in three
dimensions. We also give the special forms of this solution, which correspond
to certain critical values of the topological mass. Finally, we show that at
the special limit, the null Killing isometry of the spacetime is restored and
the solution describes AdS pp-waves.Comment: 7 pages, twocolumn REVTeX; minor changes, new references adde
Type N spacetimes as solutions of extended new massive gravity
We study algebraic type N spacetimes in the extended new massive gravity (NMG), considering both the Born-Infeld model (BI-NMG) and the model of NMG with any finite order curvature corrections. We show that for these spacetimes, the field equations of BI-NMG take the form of the massive (tensorial) Klein-Gordon type equation, just as it happens for ordinary NMG. This fact enables us to obtain the type N solution to BI-NMG, utilizing the general type N solution of NMG, earlier found in our work. We also obtain type N solutions to NMG with all finite order curvature corrections and show that, in contrast to BI-NMG, this model admits the critical point solutions, which are counterparts of "logarithmic" AdS pp-waves solutions of NMG