4,701 research outputs found
World Sheet Logarithmic CFT in AdS Strings, Ghost-Matter Mixing and M-theory
We discuss several closely related concepts in the NSR formulation of
superstring theory. We demonstrated that recently proposed NSR model for
superstrings on is described by the world-sheet logarithmic
conformal field theory (LCFT). The origin of LCFT on a world-sheet is closely
connected to the matter-ghost mixing in the structure of a brane-like vortex
operators. We suggest a dynamical origin of M theory as a string theory with an
extra dimension given by bosonised superconformal ghosts.Comment: 20 pages, no figures, harvmac, corrected some typo
Fluid Dynamics of NSR Strings
We show that the renormalization group flows of the massless superstring
modes in the presence of fluctuating D-branes satisfy the equations of fluid
dynamics.In particular, we show that the D-brane's U(1) field is related to the
velocity function in the Navier-Stokes equation while the dilaton plays the
role of the passive scalar advected by the turbulent flow. This leads us to
suggest a possible isomorphism between the off-shell superstring theory in the
presence of fluctuating branes and the fluid mechanical degrees of freedom.Comment: 24 pages Dedicated to the memory of Ian Koga
DBI Action from Closed Strings and D-brane second Quantization
Brane-like vertex operators play an important role in a worldsheet
formulation of D-branes and M-theory. In this paper we derive the DBI D-brane
action from NSR closed string sigma-model with brane-like states. We also show
that these operators carry RR charges and define D-brane wavefunctions in a
second quantized formalism.Comment: 16 pages, latex, typos corrected, BRST nontriviality condition (9)
for closed string vertices is amende
Interaction of Discrete States in Two-Dimensional String Theory
We study the couplings of discrete states that appear in the string theory
embedded in two dimensions, and show that they are given by the structure
constants of the group of area preserving diffeomorphisms. We propose an
effective action for these states, which is itself invariant under this
infinite-dimensional group.Comment: 12 page
BRST Properties of New Superstring States
Brane-like states are defined by physical vertex operators in NSR superstring
theory, existing at nonzero pictures only. These states exist both in open and
closed string theories, in the NS and NS-NS sectors respectively. In this paper
we present a detailed analysis of their BRST properties, giving a proof that
these vertex operators are physical, i.e. BRST invariant and BRST non-trivial.Comment: 25 pages, harvmac.te
The effect of using local mean versus constant reference salinity to estimate Arctic Ocean freshwater content changes
Changes of high-latitude freshwater content (FWC) play an important role in shaping the variability of polar oceans. FWC is defined as depth-integrated departure of salinity from a reference salinity Sref divided by this Sref . A constant Sref is often used for high-latitude FWC estimates. Here it is argued that for analyzing FWC spatiotemporal changes the use of local mean Sref is a better choice. Analysis of 2007 FWC anomalies in the 25–75 m layer demonstrated, for example, that the choice of Sref = 34.8 (which is often used in climate studies) leads to FWC spatial anomalies exaggerated, on average, by ~0.6 m, which is a substantial fraction of total spatial FWC changes. The problem is aggravated in areas where the difference between the local Sref and Sref = 34.8 is greater. Thus, it is concluded that using climatological mean salinities as Sref provides superior estimates of spatiotemporal Arctic Ocean FWC changes.Changes of high-latitude freshwater content (FWC) play an important role in shaping the variability of polar oceans. FWC is defined as depth-integrated departure of salinity from a reference salinity Sref divided by this Sref . A constant Sref is often used for high-latitude FWC estimates. Here it is argued that for analyzing FWC spatiotemporal changes the use of local mean Sref is a better choice. Analysis of 2007 FWC anomalies in the 25–75 m layer demonstrated, for example, that the choice of Sref = 34.8 (which is often used in climate studies) leads to FWC spatial anomalies exaggerated, on average, by ~0.6 m, which is a substantial fraction of total spatial FWC changes. The problem is aggravated in areas where the difference between the local Sref and Sref = 34.8 is greater. Thus, it is concluded that using climatological mean salinities as Sref provides superior estimates of spatiotemporal Arctic Ocean FWC changes
K*-couplings for the antidecuplet excitation
We estimate the coupling of the K* vector meson to the N-->Theta+ transition
employing unitary symmetry, vector meson dominance, and results from the GRAAL
Collaboration for eta photoproduction off the neutron. Our small numerical
value for the coupling constant is consistent with the non-observation of the
Theta+ in recent CLAS searches for its photoproduction. We also estimate the
K*-coupling for the N-->Sigma* excitation, with Sigma* being the Sigma-like
antidecuplet partner of the Theta+-baryon.Comment: 9 pages, 1 figure. Minor changes in text and abstract, references
added; version to appear in Phys. Rev.
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