2009/04/30 by Kallingalthodi Madhu, K. Narayan · 1 citation
Mathematics · Physics and Astronomy · #Black Holes and Theoretical Physics #Classical mechanics #Cosmic string #Cosmology and Gravitation Theories #Geometry #Gravitational singularity #Mathematical physics #Mathematics #Non-critical string theory #Physics #Pulsars and Gravitational Waves Research #Quantum mechanics #Singularity #String (physics) #String field theory #Theoretical physics #hep-th
paper · pdf · doi:10.1103/physrevd.79.126009
published as Phys.Rev.D79:126009,2009 · Latex, 30pgs; v2. minor clarifications, references added
arxiv created 2009/05/10 · openalex publication_date 2009/06/15 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We construct cosmological spacetimes with null Kasner-like singularities as purely gravitational solutions with no other background fields turned on. These can be recast as anisotropic plane-wave spacetimes by coordinate transformations. We analyze string quantization to find the spectrum of string modes in these backgrounds. The classical string modes can be solved for exactly in these time-dependent backgrounds, which enables a detailed study of the near-singularity string spectrum, (time-dependent) oscillator masses, and wave functions. We find that for low-lying string modes (finite oscillation number), the classical near-singularity string mode functions are nondivergent for various families of singularities. Furthermore, for any infinitesimal regularization of the vicinity of the singularity, we find a tower of string modes of ultrahigh oscillation number which propagate essentially freely in the background. The resulting picture suggests that string interactions are non-negligible near the singularity.