A bstract For ensembles of Hamiltonians that fall under the Dyson classification random matrices with ? ? {1, 2, 4}, low-temperature mean entropy can be shown to vanish as ? S ( T )? ? ?T + 1 . similar relation holds for Altland-Zirnbauer ensembles. JT gravity has been dual double-scaling limit a = 2 ensemble, classical eigenvalue density $$ \propto {e}^{S_0}\sqrt{E} <mml:math xmlns:mml="http:/...

A bstract We calculate bulk and boundary correlators in JT gravity by summing over geometries. The answers are reproduced computing suitable ensemble averages of chaotic quantum systems. then consider at large spatial separations find that semiclassical decay eventually makes way for erratic oscillations around some nonzero answer. There is no cluster decomposition because wormholes connecting ...

The local and intermediate structure of stoichiometric LaMnO3 has been studied in the pseudocubic and rhombohedral phases at high temperatures (300-1150 K). Neutron powder diffraction data were collected and a combined Rietveld and high real space resolution atomic pair distribution function analysis was carried out. The nature of the Jahn-Teller (JT) transition around 750 K is confirmed to be ...

Dynamics of ion internal transport barrier (ITB) formation and impurity transport both in the Large Helical Device (LHD) heliotron and JT-60U tokamak are described. Significant differences between heliotron and tokamak plasmas are observed. The location of the ITB moves outward during the ITB formation regardless of the sign of magnetic shear in JT-60U and the ITB becomes more localized in the ...

Jahn-Teller (JT) effect both in the absence and presence of the strong Coulomb correlation is studied theoretically focusing on the reduction ∆K of the kinetic energy gain which is directly related to the spin wave stiffness. Without the Coulomb interaction, the perturbative analysis gives ∆K/(g2/MΩ2) ∼= 0.05− 0.13 depending on the electron number [g: electronphonon(el-ph) coupling constant, M ...

In this paper we review the concepts of dynamic and static Jahn-Teller (JT) effects and study their influence in the electron paramagnetic resonance (EPR) spectra of transition metal impurities in wide gap insulators. We show that the key quantities involved in this problem are the tunneling splitting, usually denoted 3Γ, and the splitting, δ, between ∼3z2−r2 and∼x2−y2 energy levels due to the ...

The author studies a family of two-dimensional Jackiw--Teitelboim (JT) supergravites, and, by using string theory techniques, he gives them complete definition to all orders in the topological expansion. This construction provides non--perturbative formulation for JT supergravity that is well--defined and stable. Furthermore, combination analytical numerical methods, shows explicitly how physic...

In this special technical report we present fundamental studies on instability analysis. When an electromagnetic wave linearly interacts with an active medium or system, there can occur basically two types of instabilities. One of them, in which the wave grows indefinitely with tin», Is called absolute Instability, and the other, in which the wave grows spatially as it travels, is called convec...

We use the temperature of the structural phase transition to determine the Jahn-Teller (JT) coupling constant in the model derived for LaMnO3 which includes both the superexchange between S = 2 spins and the JT effect. We also investigate the dependence of the exchange constants on the value of the on-site Coulomb element U , and on the orbital ordering. Journal ref.: O. Sikora and A. M. Oleś, ...