We derive the general equations of motion for a braneworld containing a (localized) domain wall. Euclideanization gives the geometry for braneworld false vacuum decay. We explicitly derive these instantons and compute the amplitude for false vacuum decay. We also show how to construct a toy ekpyrotic instanton. Finally, we comment on braneworlds with a compact spatial direction and the adS soli...

This is a summary of the work in the author’s recent paper with this title written with Jerome Gauntlett, George Papadopoulos and Paul Townsend, hep-th/97022012. We showed how to construct hyper-Kähler 8metrics in terms of arrangements of three-dimensional hyperplanes in six-dimensional euclidean space. The slopes of the planes define two relatively prime integers (p, q). Under reduction to ten...

We study string theory on the analytically continued β deformed background proposed in hep-th/0509036. This non-static model provides a solvable conformal field theory which describes time-dependent twisted string dynamics. With the mini-superspace approach, we examine disk one-point correlators of D-branes and compute winding string pair production rate. We find that these results are consiste...

During a narrative discourse, accessibility of the referents is rarely fixed once and for all. Rather, each referent varies in accessibility as the discourse unfolds, depending on the presence and prominence of the other referents. This leads the speaker to use various referential expressions to refer to the main protagonists of the story at different moments in the narrative. This study relies...

Algorithms for generating referring expressions typically assume that an object in a scenary can be identified through a set of commonly agreed properties. This is a strong assumption, since in reality properties of objects may be perceived differently among people, due to a number of factors including vagueness, knowledge discrepancies, and limited perception capabilities. Taking these discrep...

Self-referential processing has been principally investigated using functional magnetic resonance imaging (fMRI). However, understanding of the brain functioning is not possible without careful comparison of the evidence coming from different methodological domains. This paper aims to review electroencephalographic (EEG) studies of self-referential processing and to evaluate how they correspond...

In this paper, we present a machine learning system for classifying subject ellipsis in Spanish as either referential or non-referential. To the best of our knowledge, this is the first attempt to automatically identify non-referential ellipsis in Spanish. An evaluation of our system against 6,827 finite verbs shows an accuracy of 87%.