Vortex lattice for a holographic superconductor (2009)
Maeda, Kengo, Natsuume, Makoto, Okamura, Takashi
We investigate the vortex lattice solution in a $(2+1)$-dimensional holographic model of superconductors constructed from a charged scalar condensate. The solution is obtained perturbatively near the...
Universality class of holographic superconductors (2009)
Maeda, Kengo, Natsuume, Makoto, Okamura, Takashi
We study "holographic superconductors" in various spacetime dimensions. We compute most of the static critical exponents in the linear perturbations and show that they take the standard mean-field...
Dynamic critical phenomena in the AdS/CFT duality (2008)
Maeda, Kengo, Natsuume, Makoto, Okamura, Takashi
In critical phenomena, singular behaviors arise not only for thermodynamic quantities but also for transport coefficients. We study this dynamic critical phenomenon in the AdS/CFT duality. We...
Characteristic length of an AdS/CFT superconductor (2008)
Maeda, Kengo, Okamura, Takashi
We investigate in more detail the holographic model of a superconductor recently found by Hartnoll, Herzog, and Horowitz [Phys. Rev. Lett. 101, 031601], which is constructed from a condensate of a...
A note on causal hydrodynamics for M-theory branes (2008)
Natsuume, Makoto, Okamura, Takashi
We obtain new transport coefficients of causal hydrodynamics for the M2 and the M5-brane using a Kubo-like formula proposed by Baier, Romatschke, Son, Starinets, and Stephanov (arXiv:0712.2451...
Radiation from an accelerated quark via AdS/CFT (2007)
Maeda, Kengo, Okamura, Takashi
In this paper we investigate radiation by an accelerated quark in a strongly coupled gauge theory via AdS/CFT correspondence. According to AdS/CFT dictionary, we can read off energy density or energy...
Causal hydrodynamics of gauge theory plasmas from AdS/CFT duality (2007)
Natsuume, Makoto, Okamura, Takashi
We study causal hydrodynamics (Israel-Stewart theory) of gauge theory plasmas from the AdS/CFT duality. Causal hydrodynamics requires new transport coefficients (relaxation times) and we compute them...
Comment on "Viscous hydrodynamics relaxation time from AdS/CFT correspondence" (2007)
Natsuume, Makoto, Okamura, Takashi
This is a comment to hep-th/0703243. The paper determined the relaxation time tau_pi of the shear viscous stress for the N=4 SYM from AdS/CFT correspondence. The purpose of this comment is to point...
Screening length and the direction of plasma winds (2007)
Natsuume, Makoto, Okamura, Takashi
We study the screening length of a heavy quark-antiquark pair in strongly coupled gauge theory plasmas flowing at velocity v following a proposal by Liu, Rajagopal, and Wiedemann. We analyze the...
Screening length in plasma winds (2006)
Caceres, Elena, Natsuume, Makoto, Okamura, Takashi
We study the screening length L_s of a heavy quark-antiquark pair in strongly coupled gauge theory plasmas flowing at velocity v. Using the AdS/CFT correspondence we investigate, analytically, the...
Extracting information behind the veil of horizon (2006)
Maeda, Kengo, Natsuume, Makoto, Okamura, Takashi
In AdS/CFT duality, it is often argued that information behind the event horizon is encoded even in boundary correlators. However, its implication is not fully understood. We study a simple model...
Viscosity of gauge theory plasma with a chemical potential from AdS/CFT correspondence (2006)
Maeda, Kengo, Natsuume, Makoto, Okamura, Takashi
We compute the strong coupling limit of the shear viscosity for the N=4 super-Yang-Mill theory with a chemical potential. We use the five-dimensional Reissner-Nordstrom-anti-deSitter black hole, so...
Quasinormal modes for nonextreme Dp-branes and thermalizations of super-Yang-Mills theories (2005)
Maeda, Kengo, Natsuume, Makoto, Okamura, Takashi
The nonextreme Dp-brane solutions in type II supergravity(in the near-horizon limit) are expected to be dual to (p+1)-dimensional noncompact supersymmetric Yang-Mills theories at finite temperature....
Mirror effect induced by the dilaton field on the Hawking radiation (2005)
Maeda, Kengo, Okamura, Takashi
We discuss the string creation in the near-extremal NS1 black string solution. The string creation is described by an effective field equation derived from a fundamental string action coupled to the...
Noncommutative Quantum Mechanics and Seiberg-Witten Map (2004)
Kokado, Akira, Okamura, Takashi, Saito, Takesi
In order to overcome ambiguity problem on identification of mathematical objects in noncommutative theory with physical observables, quantum mechanical system coupled to the NC U(1) gauge field in...
Hall effect in Noncommutative spaces (2003)
Kokado, Akira, Okamura, Takashi, Saito, Takesi
In order to investigate whether space coordinates are intrinsically noncommutative, we make use of the Hall effect on the two-dimensional plane. We calculate the Hall conductivity in such a way that...
Hall Effect on Noncommutative Phase Space (2002)
Kokado, Akira, Okamura, Takashi, Saito, Takesi
When phase space coordinates are noncommutative, especially including arbitrarily noncommutative momenta, the Hall effect is reinvestigated. A minimally gauge-invariant coupling of electromagnetic...
Noncommutative Hall Effect (2002)
Kokado, Akira, Okamura, Takashi, Saito, Takesi
When coordinates are noncommutative, the Hall effect is reinvestigated. The Hall conductivity is expressed with noncommutative parameters, so that in the commutative limit it tends to the...
Wigner's Formulation of Noncommutative Quantum Mechanics (2002)
Kokado, Akira, Okamura, Takashi, Saito, Takesi
When we have noncommutativity among coordinates (or conjugate momenta), we consider Wigner's formulation of quantum mechanics, including a new derivation of path integral formula. We also propose the...
A Comment on Non-Archimedean Character of Quantum Buoyancy (2000)
In a gedankenexperiment about the generalized second law (GSL) of black hole thermodynamics, the buoyant force by black hole atmosphere (the acceleration radiation) plays an important role, and then...
Entropy for Asymptotically AdS_3 Black Holes (1999)
Natsuume, Makoto, Okamura, Takashi
We propose that Strominger's method to derive the BTZ black hole entropy is in fact applicable to other asymptotically AdS_3 black holes and gives the correct functional form of entropies. We discuss...
Three-Dimensional Gravity with Conformal Scalar and Asymptotic Virasoro Algebra (1999)
Natsuume, Makoto, Okamura, Takashi, Sato, Masamichi
Strominger has derived the Bekenstein-Hawking entropy of the BTZ black hole using asymptotic Virasoro algebra. We apply Strominger's method to a black hole solution found by Martinez and Zanelli...
On scattering off the extreme Reissner-Nordstr\"om black hole in N=2 supergravity (1997)
The scattering amplitudes for the perturbed fields of the N=2 supergravity about the extreme Reissner-Nordstr\"om black hole is examined. Owing to the fact that the extreme hole is a BPS state of the...
General Theorem about Gravitational Lensing (1997)
Fukuyama, Takeshi, Okamura, Takashi
We study the general theorem about gravitational lensing which states the relationship between the numbers of images with different parities. Our formulation allows an extension to the nontransparent...
Partridge, Loren W., Mancinelli, Fabrizio., Colalucci, Gianluigi., Okamura, Takashi.
Incluye bibliografía
Perturbing Supersymmetric Black Hole (1996)
Onozawa, Hisashi, Okamura, Takashi, Mishima, Takashi, Ishihara, Hideki
An investigation of the perturbations of the Reissner-Nordstr\"{o}m black hole in the $N=2$ supergravity is presented. We prove in the extremal limit that the black hole responds to the perturbation...
Quasinormal modes of maximally charged black holes (1996)
Onozawa, Hisashi, Mishima, Takashi, Okamura, Takashi, Ishihara, Hideki
A new algorithm for computing the accurate values of quasinormal frequencies of extremal Reissner-Nordstr\"{o}m black holes is presented. The numerically computed values are consistent with the...
On Divergence of Decoherence Factor in Quantum Cosmology (1996)
To discuss the quantum to classical transition in quantum cosmology, we study the decoherence factor and the peak of the Wigner function, which respectively represent the degree of decoherence and...
On Divergence of Decoherence Factor in Quantum Cosmology (1996)
To discuss the quantum to classical transition in quantum cosmology, we study the decoherence factor and the peak of the Wigner function, which respectively represent the degree of decoherence and...
Herpes Simplex Virus in Oral Mucosal Ulcers in Patients with Hematological Malignancy (1989)
Shibuya, Tsunefumi, Moriyama, Kosei, Harada, Mine, Okamura, Takashi, Taniguchi, Shuichi, Akashi, Koichi, ...
Developments of oral mucosal ulcers induced by herpes simplex virus (HSV) were studied in patients with hematologic malignancy. Herpes simplex virus type-1 (HSV-1) was identified by immunological...
Andres, Glenn, Turner, A. Richard, Okamura, Takashi (fotografía)
Extensa y bella obra que analiza el desarollo del arte florentino (arquitectura, escultura y pintura), principalmente durante el Renacimiento, su época de mayor esplendor, aunque rastrea en los...
The Art of Florence / G. Andres, J.M. Hunisak, A.R. Turner ; fotografía de T. Okamura. (1988)
Andres, Glenn, Turner, A. Richard, Okamura, Takashi (fotografía)
Extensa y bella obra que analiza el desarollo del arte florentino (arquitectura, escultura y pintura), principalmente durante el Renacimiento, su época de mayor esplendor, aunque rastrea en los...