Perturbative Dynamics of Fractional Strings on Multiply Wound D-strings

Fractional strings in the spectrum of states of open strings attached to a multiply wound D-brane is explained. We first describe the fractional string states in the low-energy effective theory where the topology of multiple winding is encoded in the gauge holonomy. The holonomy induces twisted boundary conditions responsible for the fractional moding of these states. We also describe fractional strings in world sheet formulation and compute simple scattering amplitudes for Hawking emission/absorption. Generalization to fractional DN-strings in a 1-brane 5-brane bound state is described. When a 1-brane and a 5-brane wraps $Q_1$ and $Q_5$ times respectively around a circle, the momentum of DN-strings is quantized in units of $2 \pi/L Q_1 Q_5$. These fractional states appear naturally in the perturbative spectrum of the theory.Comment: 14 pages, LaTeX, 3 figure

Stocks in the household portfolio: a look back at the 1990s

The growing prominence of stocks as a household asset in the 1990s encouraged the view that the United States had become a nation of zealous investors alert to every market development and eager to acquire new stocks. Yet an analysis of the factors behind the rise in the household equity share suggests that exceptionally high returns on stocks_rather than aggressive investment behavior_accounted for much of the increased importance of stocks.Financial markets ; Rate of return

D-Branes and Physical States

States obtained by projecting boundary states, associated with D-branes, to fixed mass-level and momentum generically define non-trivial cohomology classes. For on-shell states the cohomology is the standard one, but when the states are off-shell the relevant cohomology is defined using a BRST operator with ghost zero modes removed. The zero momentum cohomology falls naturally into multiplets of $SO(D-1,1)$. At the massless level, a simple set of D-brane configurations generates the full set of zero-momentum states of standard ghost number, including the discrete states. We give a general construction of off-shell cohomology classes, which exhibits a non-trivial interaction between left and right movers that is not seen in on-shell cohomology. This includes, at higher mass levels, states obtained from typical D-brane boundary states as well as states with more intricate ghost dependence.Comment: 22 pages, harvmac, no figure

Report of Investigations No. 135 Oligocene Volcanism and Multiple Caldera Formation in the Chinati Mountains, Presidio County, Texas

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