arXiv subjects

Yoshifumi Hyakutake

Publications and source records attributed to Yoshifumi Hyakutake.

At least 19 recordsLinked to original sources

arXiv2025

Effective Action in M-Theory: $(DF)^4$ Superinvariants

We construct superinvariants in M-theory via local supersymmetry, which include $(DF)^4$ terms and fermionic bilinear terms with mass dimension eight. The bases of the $(DF)^4$ and the fermionic bilinear terms are classified and the variations under the local supersymmetry are evaluated by using the Mathematica codes. By imposing the local supersymmetry, we find that 24 independent terms of $(DF)^4$ are governed by 10 parameters. The result is consistent with the effective action obtained by analyzing scattering amplitudes of superparticles or supermembranes.

hep-th↗

arXiv2023

Reconstruction of Type II Supergravities via $O(d) \times O(d)$ Duality Invariants

We reconstruct type II supergravities by using building blocks of $O(d) \times O(d)$ invariants.These invariants are obtained by explicitly analyzing $O(d) \times O(d)$ transformations of 10 dimensional massless fields. Similar constructions are done by employing double field theory or generalized geometry, but we completed the reconstruction within the framework of the supergravities.

hep-th↗

arXiv2021

Cosmological Perturbations via Quantum Corrections in M-theory

In the early universe it is important to take into account quantum effect of the gravity to explain the feature of the inflation. In this paper, we consider the M-theory effective action which consists of 11 dimensional supergravity and (Weyl)$^4$ terms. The equations of motion are solved perturbatively, and the solution describes the inflation-like expansion in 4 dimensional spacetime. Scalar and tensor perturbations around this background are evaluated analytically and their behaviors are investigated numerically. If we assume that these perturbations are constant at the beginning of the inflation, spectral indices for scalar and tensor perturbations become almost scale invariant.

hep-th↗

arXiv2020

Scalar Cosmological Perturbations in M-theory with Higher Derivative Corrections

We investigate the inflationary expansion of the universe induced by higher curvature corrections in M-theory. The inflationary evolution of the geometry is discussed in ref.[1], thus we succeed to analyse metric perturbations around the background. Especially we focus on scalar perturbations and analyse linearized equations of motion for the scalar perturbations. By solving these equations explicitly, we evaluate the power spectrum of the curvature perturbation. Scalar spectrum index is estimated under some assumption, and we show that it becomes close to 1.

hep-th↗

arXiv2018

Inflationary Cosmology via Quantum Corrections in M-theory

We investigate inflationary cosmology by solving the effective action of the M-theory, which consists of the 11 dimensional supergravity and quartic terms of the Weyl tensor. The metric is simply expressed by two scale factors, one for the spatial directions and the other for the internal directions. Since the effective action of the M-theory is constructed perturbatively, we also solve the equations of motion perturbatively. We will show that the classical solution of the 11 dimensional supergravity does not represent the inflationary expansion, but if we include the quantum corrections, the behavior of the solution around the very early time is modified and the inflationary scenario is realized. The inflation naturally ends when the scalar curvature becomes small and quartic terms of the Weyl tensor are negligible.

hep-th↗

arXiv2018

Black Hole and Fuzzy Objects in BFSS Matrix Model

We analyze fuzzy configurations of D0-branes in BFSS matrix model as microstates of black hole. Fuzzy configurations of D0-branes consist of localized fuzzy objects in 3 spatial directions which are smeared into 6 internal directions. Since the solutions are time dependent, these are non-BPS configurations and have internal energy compared with static case. Especially we examine the smeared fuzzy sphere in the BFSS matrix model, which will correspond to the microstate of the charged black hole in 4 dimensions, and compare the effective potential in that background with the result obtained by the near horizon geometry of the black 0-brane. The qualitative features of two descriptions agree with each other, thus we expect the smeared fuzzy sphere corresponds to one of the microstates of the charged black hole. We also examine the smeared fuzzy cylinder which will correspond to the flat space time.

hep-th↗

arXiv2016

Quantum Aspects of Black Objects in String Theory

One of important directions in superstring theory is to reveal the quantum nature of black hole. In this paper we embed Schwarzschild black hole into superstring theory or M-theory, which we call a smeared black hole, and resolve quantum corrections to it. Furthermore we boost the smeared black hole along the 11th direction and construct a smeared quantum black 0-brane in 10 dimensions. Quantum aspects of the thermodynamic for these black objects are investigated in detail. We also discuss radiations of a string and a D0-brane from the smeared quantum black 0-brane.

hep-th↗

arXiv2016

Numerical tests of the gauge/gravity duality conjecture for D0-branes at finite temperature and finite N

According to the gauge/gravity duality conjecture, the thermodynamics of gauge theory describing D-branes corresponds to that of black branes in superstring theory. We test this conjecture directly in the case of D0-branes by applying Monte Carlo methods to the corresponding gauge theory, which takes the form of the BFSS matrix quantum mechanics. In particular, we take the continuum limit by extrapolating the UV cutoff to infinity. First we perform simulations at large N so that string loop corrections can be neglected on the gravity side. Our results for the internal energy exhibit the temperature dependence consistent with the prediction including the α' corrections. Next we perform simulations at small N but at lower temperature so that the α' corrections can be neglected on the gravity side. Our results are consistent with the prediction including the leading string loop correction, which suggests that the conjecture holds even at finite N.

hep-th↗

arXiv2015

Boosted Quantum Black Hole and Black String in M-theory, and Quantum Correction to Gregory-Laflamme Instability

We take into account higher derivative R4 corrections in M-theory and construct quantum black hole and black string solutions in 11 dimensions up to the next leading order. The quantum black string is stretching along the 11th direction and the Gregory-Laflamme instability is examined at the quantum level. Thermodynamics of the boosted quantum black hole and black string are also discussed. Especially we take the near horizon limit of the quantum black string and investigate its instability quantitatively.

gr-qc↗

arXiv2015

Super Virasoro Algebras From Chiral Supergravity

In this note, we construct Noether charges for the chiral supergravity, which contains the Lorentz Chern-Simons term, by applying Wald's prescription to the vielbein formalism. We investigate the AdS3/CFT2 correspondence by using the vielbein formalism. The asymptotic symmetry group is carefully examined by taking into account the local Lorentz transformation, and we construct super Virasoro algebras with central extensions from the chiral supergravity.

hep-th↗

arXiv2015

Quantum M-wave and Black 0-brane

The effective action of superstring theory or M-theory is approximated by supergravity in the low energy limit, and quantum corrections to the supergravity are taken into account by including higher derivative terms. In this paper, we consider equations of motion with those higher derivative terms in M-theory and solve them to derive quantum M-wave solution. A quantum black 0-brane solution is also obtained by Kaluza-Klein dimensional reduction of the M-wave solution. The quantum black 0-brane is asymptotically flat and uniquely determined by imposing appropriate conditions. The mass and the R-R charge of the quantum black 0-brane are derived by using the ADM mass and the charge formulae, and we see that only the mass is affected by the quantum correction. Various limits of the quantum black 0-brane are also considered, and especially we show that an internal energy in the near horizon limit is correctly reproduced.

hep-th↗

arXiv2015

Quantum Near Horizon Geometry of Black 0-Brane

We investigate a bunch of D0-branes to reveal its quantum nature from the gravity side. In the classical limit, it is well described by a non-extremal black 0-brane in type IIA supergravity. The solution is uplifted to the eleven dimensions and expressed by a non-extremal M-wave solution. After reviewing the effective action for the M-theory, we explicitly solve the equations of motion for the near horizon geometry of the M-wave. As a result we derive an unique solution which includes the effect of the quantum gravity. Thermodynamic property of the quantum near horizon geometry of the black 0-brane is also studied by using Wald's formula. Combining our result with that of the Monte Carlo simulation of the dual thermal gauge theory, we find strong evidence for the gauge/gravity duality in the D0-branes system at the level of quantum gravity.

hep-th↗

arXiv2013

Holographic description of quantum black hole on a computer

The discovery of the fact that black holes radiate particles and eventually evaporate led Hawking to pose the well-known information loss paradox. This paradox caused a long and serious debate since it claims that the fundamental laws of quantum mechanics may be violated. A possible cure appeared recently from superstring theory, a consistent theory of quantum gravity: if the holographic description of a quantum black hole based on the gauge/gravity duality is correct, the information is not lost and quantum mechanics remains valid. Here we test this gauge/gravity duality on a computer at the level of quantum gravity for the first time. The black hole mass obtained by Monte Carlo simulation of the dual gauge theory reproduces precisely the quantum gravity effects in an evaporating black hole. This result opens up totally new perspectives towards quantum gravity since one can simulate quantum black holes through dual gauge theories.

hep-th↗

arXiv2012

Super Virasoro Algebra From Supergravity

We investigate AdS3/CFT2 correspondence in three dimensional supergravity. We construct a current for general coordinate invariance and that for local supersymmetry via covariant approach. Hamiltonian and supercharge are well defined in terms of vielbein and spin connection. After discussing asymptotic supersymmetry group at the boundary of AdS3 geometry, we show that there exist a direct product of Virasoro algebras at the boundary. We also show that one of them is extended to super Virasoro algebra.

hep-th↗

arXiv2009

Left-Right Asymmetric Holographic RG Flow with Gravitational Chern-Simons Term

We consider the holographic renormalization group (RG) flow in three dimensional gravity with the gravitational Chern-Simons term coupled to some scalar fields. We apply the canonical approach to this higher derivative case and employ the Hamilton-Jacobi formalism to analyze the flow equations of two dimensional field theory. Especially we obtain flow equations of Weyl and gravitational anomalies, and derive $c$-functions for left and right moving modes. Both of them are monotonically non-increasing along the flow, and the difference between them is determined by the coefficient of the gravitational Chern-Simons term. This is completely consistent with the Zamolodchikov's $c$-theorem for parity-violating two-dimensional quantum field theories.

hep-th↗

arXiv2009

Higher derivative corrections to black hole thermodynamics from supersymmetric matrix quantum mechanics

We perform a direct test of the gauge-gravity duality associated with the system of N D0-branes in type IIA superstring theory at finite temperature. Based on the fact that higher derivative corrections to the type IIA supergravity action start at the order of α'^3, we derive the internal energy in expansion around infinite 't Hooft coupling up to the subleading term with one unknown coefficient. The power of the subleading term is shown to be nicely reproduced by the Monte Carlo data obtained nonperturbatively on the gauge theory side at finite but large effective (dimensionless) 't Hooft coupling constant. This suggests, in particular, that the open strings attached to the D0-branes provide the microscopic origin of the black hole thermodynamics of the dual geometry including α' corrections. The coefficient of the subleading term extracted from the fit to the Monte Carlo data provides a prediction for the gravity side, which can be checked once the complete form of the O(α'^3) corrections to the supergravity action is obtained.

hep-th↗

arXiv2008

Brown-Henneaux's Canonical Approach to Topologically Massive Gravity

We analyze the symmetry realized asymptotically on the two dimensional boundary of AdS_3 geometry in topologically massive gravity, which consists of the gravitational Chern-Simons term as well as the usual Einstein-Hilbert and negative cosmological constant terms. Our analysis is based on the conventional canonical method and proceeds along the line completely parallel to the original Brown and Henneaux's. In spite of the presence of the gravitational Chern-Simons term, it is confirmed by the canonical method that the boundary theory actually has the conformal symmetry satisfying the left and right moving Virasoro algebras. The central charges of the Virasoro algebras are computed explicitly and are shown to be left-right asymmetric due to the gravitational Chern-Simons term. It is also argued that the Cardy's formula for the BTZ black hole entropy capturing all higher derivative corrections agrees with the extended version of the Wald's entropy formula. The M5-brane system is illustrated as an application of the present calculation.

hep-th↗

arXiv2007

Higher Derivative Corrections in M-theory via Local Supersymmetry

We investigate higher derivative corrections in M-theory by applying Noether's method. Cancellation of variations, which contain linear terms in 4-form field strength, under local supersymmetry is executed with the aid of computer programming. Structure of $R^4$ terms is uniquely determined and exactly matches with one-loop effective terms in type IIA superstring theory.

hep-th↗