ND Tadpoles as New String States and Quantum Mechanical Particle-Wave Duality from World-Sheet T-Duality

We consider new objects in bosonic open string theory -- ND tadpoles, which have N(euman) boundary conditions at one end of the world-sheet and D(irichlet) at the other, must exist due to s-t duality in a string theory with both NN strings and D-branes. We demonstrate how to interpolate between N and D boundary conditions. In the case of mixed boundary conditions the action for a quantum particle is induced on the boundary. Quantum-mechanical particle-wave duality, a dual description of a quantum particle in either the coordinate or the momentum representation, is induced by world-sheet T-duality. The famous relation between compactification radii is equivalent to the quantization of the phase space area of a Planck cell. We also introduce a boundary operator - a ``Zipper'' which changes the boundary condition from N into D and vice versa.Comment: 10 pages plain LateX2e, 4 eps figures included using epsf. Revised version with extra reference

Boundary Logarithmic Conformal Field Theory

We discuss the effect of boundaries in boundary logarithmic conformal field theory and show, with reference to both $c=-2$ and $c=0$ models, how they produce new features even in bulk correlation functions which are not present in the corresponding models without boundaries. We discuss the modification of Cardy's relation between boundary states and bulk quantities.Comment: 17 pages,3 eps figures, revised final section, clarification added in a couple of other places, typos correcte

What does E_8 know about 11 dimensions ?

We discuss some possible relationships in gauge theories, string theory and M theory in the light of some recent results obtained in gauge invariant supersymmetric quantum mechanics. In particular this reveals a new relationship between the gauge group E_8 and 11-dimensional space.Comment: 6 pages, Latex, no figure

Statistics of fluctuations for two types of crossover: from ballistic to diffusive regime and from orthogonal to unitary ensemble

In our previous publication [Kogan et al, Phys. Rev. {\bf 48}, 9404 (1993)] we considered the issue of statistics of radiation diffusively propagating in a disordered medium. The consideration was in the framework of diagrammatic techniques and a new representation for the intensity distribution function in terms of connected diagrams only was proposed. Here we use similar approach to treat the issue of statistics in the regime of the crossover between ballistic and diffusive transport. We find that even small contribution from coherent component decreases by one half the intensity distribution function for small values of intensity and also produces oscillations of the distribution function. We also apply this method to study statistics of fluctuations of wave functions of chaotic electrons in a quantum dot in an arbitrary magnetic field, by calculating the single state local density in the regime of the crossover between the orthogonal and unitary ensemble.Comment: Revtex, 3 pages + 2 ps.figures in uuencoded file, a version which clarifies and unites the results of two previous submission

Time delay between the optical and X-ray outbursts in the high mass X-ray transient A0535+26/HDE245770

The optical behaviour of the Be star in the high mass X-ray transient A0535+26/HDE245770 shows that at the periastron typically there is an enhancement in the luminosity of order 0.02 to few tenths mag, and the X-ray outburst happens about 8 days after the periastron. We construct a quantitative model of this event, basing on the a nonstationary accretion disk behavior, connected with a high ellipticity of the orbital motion. The ephemeris used in this paper -- JD$_{\rm opt-outb}$ = JD$_0$(2,444,944) $\pm$ n(111.0 $\pm$ 0.4) days are derived from the orbital period of the system P$_{\rm orb} = 111.0 \pm 0.4$ days, determined by Priedhorsky & Terrell (1983), and from the optical flare of December 5, 1981 (Giovannelli et al., 1985) (here after 811205-E; E stands for the Event occurred at that date) that triggered the subsequent X-ray outburst of December 13, 1981 (Nagase et al., 1982) (here after 811213-E). We explain the observed time delay between the peaks of the optical and X-ray outbursts in this system by the time of radial motion of the matter in the accretion disk, after an increase of the mass flux in the vicinity of a periastral point in the binary. This time is determined by the turbulent viscosity, with the parameter $\alpha=0.1-0.3$. The increase of the mass flux is a sort of flush that reaches the external part of the accretion disk around the neutron star, producing an enhancement in the optical luminosity. The consequent X-ray flare happens when the matter reaches the hot central parts of the accretion disk, and the neutron star surface.Comment: 30 pages, 15 figures, with correction in abstrac

Dynamical chaos in the problem of magnetic jet collimation

We investigate dynamics of a jet collimated by magneto-torsional oscillations. The problem is reduced to an ordinary differential equation containing a singularity and depending on a parameter. We find a parameter range for which this system has stable periodic solutions and study bifurcations of these solutions. We use Poincar\'e sections to demonstrate existence of domains of regular and chaotic motions. We investigate transition from periodic to chaotic solutions through a sequence of period doublings.Comment: 11 pages, 29 figures, 1 table, MNRAS (published online

Durability of Output and Expected Stock Returns

The demand for durable goods is more cyclical than that for nondurable goods and services. Consequently, the cash flows and stock returns of durable-good producers are exposed to higher systematic risk. Using the benchmark input-output accounts of the National Income and Product Accounts, we construct portfolios of durable-good, nondurable-good, and service producers. In the cross-section, an investment strategy that is long on the durable-good portfolio and short on the service portfolio earns a risk premium exceeding 4 percent annually. In the time series, an investment strategy that is long on the durable-good portfolio and short on the market portfolio earns a countercyclical risk premium. We explain these findings in a general equilibrium asset-pricing model with endogenous production.

Analytic solution for kinetic equilibrium of beta-processes in nucleonic plasma with relativistic pairs

The analytic solution is obtained describing kinetic equilibrium of the $\beta$-processes in the nucleonic plasma with relativistic pairs. The nucleons $(n,p)$ are supposed to be non-relativistic and non-degenerate, while the electrons and positrons are ultra-relativistic due to high temperature $(T>6\cdot 10^9$K), or high density $(\rho>\mu 10^6$g/cm$^3$), or both, where $\mu$ is a number of nucleons per one electron. The consideration is simplified because of the analytic connection of the density with the electron chemical potential in the ultra-relativistic plasma, and Gauss representation of Fermi functions. Electron chemical potential and number of nucleons per one initial electron are calculated as functions of $\rho$ and $T$.Comment: 16 pages, 6 figure