D-branes in 2d Lorentzian black hole

We study D-branes in the Lorentzian signature 2D black hole string theory. We use the technique of gauged WZW models to construct the associated boundary conformal field theories. The main focus of this work is to discuss the (semi-classical) world-volume geometries of the D-branes. We also discuss comparison of our work with results in related gauged WZW models.Comment: 24 pages, 5 figures, uses JHEP3.cl

String Theoretic Bounds on Lorentz-Violating Warped Compactification

We consider warped compactifications that solve the 10 dimensional supergravity equations of motion at a point, stabilize the position of a D3-brane world, and admit a warp factor that violates Lorentz invariance along the brane. This gives a string embedding of ``asymmetrically warped'' models which we use to calculate stringy (\alpha') corrections to standard model dispersion relations, paying attention to the maximum speeds for different particles. We find, from the dispersion relations, limits on gravitational Lorentz violation in these models, improving on current limits on the speed of graviton propagation, including those derived from field theoretic loops. We comment on the viability of models that use asymmetric warping for self-tuning of the brane cosmological constant.Comment: 20pg, JHEP3; v2 additional references, slight change to intro; v3. added referenc

Production and marketing of sheepmeat in Greece in the context of the European Community's Common Agricultural Policy

SIGLEAvailable from British Library Document Supply Centre- DSC:D66592/86 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Characterization of the LIGO detectors during their sixth science run

In 2009-2010, the Laser Interferometer Gravitational-Wave Observatory (LIGO) operated together with international partners Virgo and GEO600 as a network to search for gravitational waves (GWs) of astrophysical origin. The sensitivity of these detectors was limited by a combination of noise sources inherent to the instrumental design and its environment, often localized in time or frequency, that couple into the GW readout. Here we review the performance of the LIGO instruments during this epoch, the work done to characterize the detectors and their data, and the effect that transient and continuous noise artefacts have on the sensitivity of LIGO to a variety of astrophysical sources