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 \alpha'^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 \alpha' 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(\alpha'^3) corrections to the supergravity action is obtained.Comment: REVTeX4, 4 pages, 2 figures. Ver.2:intuitive derivation of the subleading term adde

Absence of spectral peaks in short-period oscillations from the Chilean Earthquake

On the occasion of the great Chilean earthquake of May 1960, various modes of free oscillations of the earth were observed: spheroidal oscillations of wave number n = 2 (period 53 min) to 38 (3.7 min) [Benioff et al., 1961; Ness et al., 1961; Alsop et al., 1961; Bogert, 1961] and torsional oscillations of n up to 24 (5.2 min) [Bolt and Marussi, 1962; Brune et al., 1961]. From a rather negative result that the shorter-period oscillations were not well observed, we try here to deduce some conclusions regarding the earth's upper mantle structure or the oscillation mechanism of the earthquake. The result may be due to horizontal inhomogeneities of the upper mantle of the earth making the resolution of spectral peaks in shorter-period oscillations difficult, or it may be due to weak excitation of shorter-period oscillations by the source

Reliable stereo matching for highly-safe intelligent vehicles and its VLSI implementation

科研費報告書収録論文(課題番号:12555119・基盤研究(B)(2) ・H12～H14/研究代表者:亀山, 充隆/最適構成理論に基づく高安全知能自動車用VLSIプロセッサチップファミリの開発

Schwarzschild radius from Monte Carlo calculation of the Wilson loop in supersymmetric matrix quantum mechanics

In the string/gauge duality it is important to understand how the space-time geometry is encoded in gauge theory observables. We address this issue in the case of the D0-brane system at finite temperature T. Based on the duality, the temporal Wilson loop operator W in gauge theory is expected to contain the information of the Schwarzschild radius R_{Sch} of the dual black hole geometry as log = R_{Sch} / (2 pi alpha' T). This translates to the power-law behavior log = 1.89 (T/lambda^{1/3})^{-3/5}, where lambda is the 't Hooft coupling constant. We calculate the Wilson loop on the gauge theory side in the strongly coupled regime by performing Monte Carlo simulation of supersymmetric matrix quantum mechanics with 16 supercharges. The results reproduce the expected power-law behavior up to a constant shift, which is explainable as alpha' corrections on the gravity side.Comment: REVTeX4, 4 pages, 1 figur

Non-lattice simulation for supersymmetric gauge theories in one dimension

Lattice simulation of supersymmetric gauge theories is not straightforward. In some cases the lack of manifest supersymmetry just necessitates cumbersome fine-tuning, but in the worse cases the chiral and/or Majorana nature of fermions makes it difficult to even formulate an appropriate lattice theory. We propose to circumvent all these problems inherent in the lattice approach by adopting a non-lattice approach in the case of one-dimensional supersymmetric gauge theories, which are important in the string/M theory context.Comment: REVTeX4, 4 pages, 3 figure

TANK prevents IFN-dependent fatal diffuse alveolar hemorrhage by suppressing DNA-cGAS aggregation

Diffuse alveolar hemorrhage (DAH) is one of the serious complications associated with systemic lupus erythematosus, an autoimmune disease whose pathogenesis involves type I IFNs and cytokines. Here, we show that TANK, a negative regulator of the NF-κB signaling via suppression of TRAF6 ubiquitination, is critical for the amelioration of fatal DAH caused by lung vascular endothelial cell death in a mouse model of systemic lupus erythematosus. The development of fatal DAH in the absence of TANK is mediated by type I IFN signaling, but not IL-6. We further uncover that STING, an adaptor essential for the signaling of cytoplasmic DNA sensor cyclic GMP-AMP (cGAMP) synthase (cGAS), plays a critical role in DAH under Tank deficiency. TANK controls cGAS-mediated cGAMP production and suppresses DNA-mediated induction of IFN-stimulated genes in macrophages by inhibiting the formation of DNA-cGAS aggregates containing ubiquitin. Collectively, TANK inhibits the cGAS-dependent recognition of cytoplasmic DNA to prevent fatal DAH in the murine lupus model

Precise Estimation of Cosmological Parameters Using a More Accurate Likelihood Function

The estimation of cosmological parameters from a given data set requires a construction of a likelihood function which, in general, has a complicated functional form. We adopt a Gaussian copula and constructed a copula likelihood function for the convergence power spectrum from a weak lensing survey. We show that the parameter estimation based on the Gaussian likelihood erroneously introduces a systematic shift in the confidence region, in particular for a parameter of the dark energy equation of state w. Thus, the copula likelihood should be used in future cosmological observations.Comment: 5 pages, 3 figures. Maches version published by the Physical Review Letter

Monte Carlo studies of supersymmetric matrix quantum mechanics with sixteen supercharges at finite temperature

We present the first Monte Carlo results for supersymmetric matrix quantum mechanics with sixteen supercharges at finite temperature. The recently proposed non-lattice simulation enables us to include the effects of fermionic matrices in a transparent and reliable manner. The internal energy nicely interpolates the weak coupling behavior obtained by the high temperature expansion, and the strong coupling behavior predicted from the dual black hole geometry. The Polyakov line takes large values even at low temperature suggesting the absence of a phase transition in sharp contrast to the bosonic case. These results provide highly non-trivial evidences for the gauge/gravity duality.Comment: REVTeX4, 4 pages, 3 figure

Next-Generation A/D Sampler ADS3000+ for VLBI2010

A high-speed A/D sampler, called ADS3000+, has been developed in 2008, which can sample one analog signal up to 4 Gbps to versatile Linux PC. After A/D conversion, the ADS3000+ can perform digital signal processing such as real-time DBBC (Digital Base Band Conversion) and FIR filtering such as simple CW RFI filtering using the installed FPGAs. A 4 Gsps fringe test with the ADS3000+ has been successfully performed. The ADS3000+ will not exclusively be used for VLBI but will also be employed in other applications