Scaling solution for cosmological sigma models at large N

Feb, 1991
14 pages
Published in:
  • Phys.Rev.Lett. 66 (1991) 3093-3096
Report number:
  • PUPT-90-1238

Citations per year

1991199920072015202302468
Abstract: (APS)
We study the evolution of the nonlinear O(N) σ model in an expanding universe in the large-N approximation, where one can solve exactly for the scaling field distribution, incorporating the full nonlinear dynamics. This provides a valuable analytic approximation for theories of cosmic global monopoles (N=3), global texture (N=4), and ‘‘nontopological texture’’ (N>4). The analytic results are compared with those from numerical simulations, with good agreement. The probability distribution for mass fluctuations in the linear regime is positively skewed, providing a distinctive test for the theory.
  • astrophysics
  • sigma model: nonlinear
  • symmetry: O(N)
  • scaling
  • numerical calculations
  • expansion 1/N