161 citations · 1.1k across the 37 of their papers we have counts for
23 papers · 1 filter
New family of C-metrics in gauged supergravity
Masato Nozawa, Takashi Torii
We present a new family of charged C-metrics in gauged supergravity in four dimensions. The double Wick rotation of the C-metric allows us to bring our solution into a…
6D (1,1) Gauged Supergravities from Orientifold Compactifications
Giuseppe Dibitetto, Jose J. Fernandez-Melgarejo, Masato Nozawa
We study dimensional reductions of M-theory/type II strings down to 6D in the presence of fluxes and spacetime filling branes and orientifold planes of different types. We classify…
Euclidean supersymmetric solutions with the self-dual Weyl tensor
Masato Nozawa
We explore the Euclidean supersymmetric solutions admitting the self-dual gauge field in the framework of minimal gauged supergravity in four dimensions. According to…
Supersymmetric black lenses in five dimensions
Shinya Tomizawa, Masato Nozawa
We present an asymptotically flat supersymmetric black lens solution with the horizon topology L(n,1)=S^3/Z_n in the five-dimensional minimal ungauged supergravity. We show that th…
Black holes in an expanding universe and supersymmetry
Dietmar Klemm, Masato Nozawa
This paper analyzes the supersymmetric solutions to five and six-dimensional minimal (un)gauged supergravities for which the bilinear Killing vector constructed from the Killing sp…
Killing-Yano tensor and supersymmetry of the self-dual Plebanski-Demianski solution
Masato Nozawa, Tsuyoshi Houri
We explore various aspects of the self-dual Plebański-Demiański family in the Euclidean Einstein-Maxwell- system. The Killing-Yano tensor which was recently found by Yasui and o…
On the integrability of Einstein-Maxwell-(A)dS gravity in presence of Killing vectors
Dietmar Klemm, Masato Nozawa, Marco Rabbiosi
We study some symmetry and integrability properties of four-dimensional Einstein-Maxwell gravity with nonvanishing cosmological constant in the presence of Killing vectors. First o…
Hairy black holes in N=2 gauged supergravity
Federico Faedo, Dietmar Klemm, Masato Nozawa
We construct black holes with scalar hair in a wide class of four-dimensional N=2 Fayet-Iliopoulos gauged supergravity theories that are characterized by a prepotential containing…
Geometry of Killing spinors in neutral signature
Dietmar Klemm, Masato Nozawa
We classify the supersymmetric solutions of minimal gauged supergravity in four dimensions with neutral signature. They are distinguished according to the sign of the cosmolo…
Inflation in maximal gauged supergravities
Hideo Kodama, Masato Nozawa
We discuss the dynamics of multiple scalar fields and the possibility of realistic inflation in the maximal gauged supergravity. In this paper, we address this problem in the frame…
Positive mass theorem in extended supergravities
Masato Nozawa, Tetsuya Shiromizu
Following the Witten-Nester formalism, we present a useful prescription using Weyl spinors towards the positivity of mass. As a generalization of arXiv:1310.1663, we show that some…
Supersymmetry of the C-metric and the general Plebanski-Demianski solution
Dietmar Klemm, Masato Nozawa
We derive the necessary and sufficient conditions under which the general Plebanski-Demianski (PD) solution of Einstein-Maxwell theory with a negative cosmological constant admits…
Classification and stability of vacua in maximal gauged supergravity
Hideo Kodama, Masato Nozawa
This article presents a systematic study of critical points for the SL(8, R)-type gauging in four dimensional maximal gauged supergravity. We determine all the possible vacua for w…
Parity Violation in Graviton Non-gaussianity
Jiro Soda, Hideo Kodama, Masato Nozawa
We study parity violation in graviton non-gaussianity generated during inflation. We develop a useful formalism to calculate graviton non-gaussianity. Using this formalism, we expl…
Black hole solutions in string theory
Kei-ichi Maeda, Masato Nozawa
Supersymmetric solutions of supergravity have been of particular importance in the advances of string theory. This article reviews the current status of black hole solutions in hig…
On the Bogomol'nyi bound in Einstein-Maxwell-dilaton gravity
Masato Nozawa
It has been shown that the 4-dimensional Einstein-Maxwell-dilaton theory allows a Bogomol'nyi-type inequality for an arbitrary dilaton coupling constant , and that the bound is…
Cosmological rotating black holes in five-dimensional fake supergravity
Masato Nozawa, Kei-ichi Maeda
In recent series of papers, we found an arbitrary dimensional, time-evolving and spatially-inhomogeneous solutions in Einstein-Maxwell-dilaton gravity with particular couplings. Si…
Black Hole in the Expanding Universe from Intersecting Branes
Kei-ichi Maeda, Masato Nozawa
We study physical properties and global structures of a time-dependent, spherically symmetric solution obtained via the dimensional reduction of intersecting M-branes. We find that…
Stability of branes trapped by d-dimensional black holes
Kenta Hioki, Umpei Miyamoto, Masato Nozawa
The system of extended objects interplaying with a black hole describes or mimics various gravitational phenomena. In this brief paper, we report the results of stability analysis…
Quasinormal modes of black holes localized on the Randall-Sundrum 2-brane
Masato Nozawa, Tsutomu Kobayashi
We investigate conformal scalar, electromagnetic, and massless Dirac quasinormal modes of a brane-localized black hole. The background solution is the four-dimensional black hole o…
Bulk scalar emission from a rotating black hole pierced by a tense brane
Tsutomu Kobayashi, Masato Nozawa, Yu-ichi Takamizu
We study the emission of scalar fields into the bulk from a six-dimensional rotating black hole pierced by a 3-brane. We determine the angular eigenvalues in the presence of finite…
Generalized Misner-Sharp quasi-local mass in Einstein-Gauss-Bonnet gravity
Hideki Maeda, Masato Nozawa
We investigate properties of a quasi-local mass in a higher-dimensional spacetime having symmetries corresponding to the isomertries of an -dimensional maximally symmetric s…
Energy Extraction from Higher Dimensional Black Holes and Black Rings
Masato Nozawa, Kei-ichi Maeda
We analyze the energy extraction by the Penrose process in higher dimensions. Our result shows the efficiency of the process from higher dimensional black holes and black rings can…