2003/03/31 by Frédéric Leblond, Frederic Leblond, Amanda W. Peet +1 · 3 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Curvature #Dilaton #Naked singularity #Noncommutative and Quantum Gravity Theories #Quantum Electrodynamics and Casimir Effect #Singularity #Spacetime #String cosmology #String theory #Tachyon #Tachyon condensation #hep-th
paper · pdf · doi:10.1088/1126-6708/2003/04/048
published as JHEP 0304 (2003) 048 · References added. Analysis for much broader range of solutions presented. Conclusions unchanged. Time-reversal symmetric examples ruled out, new examples are provided
arxiv created 2003/04/16 · openalex publication_date 2003/04/28 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
S(pacelike)D-branes are objects arising naturally in string theory when Dirichlet boundary conditions are imposed on the time direction. SD-brane physics is inherently time-dependent. Previous investigations of gravity fields of SD-branes have yielded undesirable naked spacelike singularities. We set up the problem of coupling the most relevant open-string tachyonic mode to massless closed-string modes in the bulk, with backreaction and Ramond-Ramond fields included. We find solutions numerically in a self-consistent approximation; our solutions are naturally asymptotically flat and time-reversal asymmetric. We find completely nonsingular evolution; in particular, the dilaton and curvature are well-behaved for all time. The essential mechanism for spacetime singularity resolution is the inclusion of full backreaction between the bulk fields and the rolling tachyon. Our analysis is not the final word on the story, because we have to make some significant approximations, most notably homogeneity of the tachyon on the unstable branes. Nonetheless, we provide significant progress in plugging a gaping hole in prior understanding of the gravity fields of SD-branes.