10,536 research outputs found

### A note on fermionic flows of the N=(1|1) supersymmetric Toda lattice hierarchy

We extend the Sato equations of the N=(1|1) supersymmetric Toda lattice
hierarchy by two new infinite series of fermionic flows and demonstrate that
the algebra of the flows of the extended hierarchy is the Borel subalgebra of
the N=(2|2) loop superalgebra.Comment: 4 pages LaTe

### Hot-pressed silicon nitride with various lanthanide oxides as sintering additives

The effects of addition of various lanthanide oxides and their mixture with Y2O3 on the sintering of Si3N4 were investigated. The addition of simple and mixed lanthanide oxides promoted the densification of Si3N4 in hot-pressing at 1800 C under 300-400kg/ centimeters squared for 60 min. The crystallization of yttrium and lanthanide-silicon oxynitrides which was observed inn the sintered body containing yttrium-lanthanide mixed oxides as additives led to the formation of a highly refractory Si3N4 ceramic having a bending strength of 82 and 84 kg/millimeters squared at room temperature and 1300 C respectively. In a Y2O3+La2O3 system, a higher molar ratio of La2O3 to Y2O3 gave a higher hardness and strength at high temperatures. It was found that 90 min was an optimum sintering time for the highest strength

### The correspondence between Tracy-Widom (TW) and Adler-Shiota-van Moerbeke (ASvM) approaches in random matrix theory: the Gaussian case

Two approaches (TW and ASvM) to derivation of integrable differential
equations for random matrix probabilities are compared. Both methods are
rewritten in such a form that simple and explicit relations between all TW
dependent variables and $\tau$-functions of ASvM are found, for the example of
finite size Gaussian matrices. Orthogonal function systems and Toda lattice are
seen as the core structure of both approaches and their relationship.Comment: 20 pages, submitted to Journal of Mathematical Physic

### Abelian Conformal Field theories and Determinant Bundles

The present paper is the first in a series of papers, in which we shall
construct modular functors and Topological Quantum Field Theories from the
conformal field theory developed in [TUY].
The basic idea is that the covariant constant sections of the sheaf of vacua
associated to a simple Lie algebra over Teichm\"uller space of an oriented
pointed surface gives the vectorspace the modular functor associates to the
oriented pointed surface. However the connection on the sheaf of vacua is only
projectively flat, so we need to find a suitable line bundle with a connection,
such that the tensor product of the two has a flat connection.
We shall construct a line bundle with a connection on any family of pointed
curves with formal coordinates. By computing the curvature of this line bundle,
we conclude that we actually need a fractional power of this line bundle so as
to obtain a flat connection after tensoring. In order to functorially extract
this fractional power, we need to construct a preferred section of the line
bundle.
We shall construct the line bundle by the use of the so-called $bc$-ghost
systems (Faddeev-Popov ghosts) first introduced in covariant quantization [FP].
We follow the ideas of [KNTY], but decribe it from the point of view of [TUY].Comment: A couple of typos correcte

### Integrable Hierarchies and Contact Terms in u-plane Integrals of Topologically Twisted Supersymmetric Gauge Theories

The $u$-plane integrals of topologically twisted $N = 2$ supersymmetric gauge
theories generally contain contact terms of nonlocal topological observables.
This paper proposes an interpretation of these contact terms from the point of
view of integrable hierarchies and their Whitham deformations. This is inspired
by Mari\~no and Moore's remark that the blowup formula of the $u$-plane
integral contains a piece that can be interpreted as a single-time tau function
of an integrable hierarchy. This single-time tau function can be extended to a
multi-time version without spoiling the modular invariance of the blowup
formula. The multi-time tau function is comprised of a Gaussian factor
$e^{Q(t_1,t_2,...)}$ and a theta function. The time variables $t_n$ play the
role of physical coupling constants of 2-observables $I_n(B)$ carried by the
exceptional divisor $B$. The coefficients $q_{mn}$ of the Gaussian part are
identified to be the contact terms of these 2-observables. This identification
is further examined in the language of Whitham equations. All relevant
quantities are written in the form of derivatives of the prepotential.Comment: latex, 17 pages, no figures; final version for publicatio

### Renormalization-group and numerical analysis of a noisy Kuramoto-Sivashinsky equation in 1+1 dimensions

The long-wavelength properties of a noisy Kuramoto-Sivashinsky (KS) equation
in 1+1 dimensions are investigated by use of the dynamic renormalization group
(RG) and direct numerical simulations. It is shown that the noisy KS equation
is in the same universality class as the Kardar-Parisi-Zhang (KPZ) equation in
the sense that they have scale invariant solutions with the same scaling
exponents in the long-wavelength limit. The RG analysis reveals that the RG
flow for the parameters of the noisy KS equation rapidly approach the KPZ fixed
point with increasing the strength of the noise. This is supplemented by the
numerical simulations of the KS equation with a stochastic noise, in which the
scaling behavior of the KPZ equation can be easily observed even in the
moderate system size and time.Comment: 12pages, 7figure

### Detection of Minimum-Ionizing Particles and Nuclear Counter Effect with Pure BGO and BSO Crystals with Photodiode Read-out

Long BGO (Bismuth Germanate) and BSO (Bismuth Silicate) crystals coupled with
silicon photodiodes have been used to detect minimum-ionizing particles(MIP).
With a low noise amplifier customized for this purpose, the crystals can detect
MIPs with an excellent signal-to-noise ratio. The NCE(Nuclear Counter Effect}
is also clearly observed and measured. Effect of full and partial wrapping of a
reflector around the crystal on light collection is also studied.Comment: 18 pages, including 5 figures; LaTeX and EP

### Toda Lattice Hierarchy and Zamolodchikov's Conjecture

In this letter, we show that certain Fredholm determinant $D(\lambda;t)$,
introduced by Zamolodchikov in his study of 2D polymers, is a continuum limit
of soliton solution for the Toda lattice hierarchy with 2-periodic reduction
condition.Comment: 6 pages, LaTeX file, no figure

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