Basic HTML version of Foils prepared 15 March 1996

Foil 27 The Lapse and Shift in Gauge Transformations

From Numerical Formulation and Solution of Collision 0f two Black Holes CPSP713 Case studies in Computational Science -- Spring Semester 1996. by Geoffrey C. Fox


The Lapse describes how much time elapses between two spacial surfaces
The Shift functions N i describe the tangential shift as you move from the t 0 to t 0+ dt spacial surface
Choose Lapse and Shift to:
  • Avoid Unphysical Singularities (One cannot avoid physical black hole singularity
    • Choice of spherical polar coordinates has singularity at radius r=0.
  • Keep Numerical Algorithm Stable
  • Insure Consistency of Constraints



© Northeast Parallel Architectures Center, Syracuse University, npac@npac.syr.edu

If you have any comments about this server, send e-mail to webmaster@npac.syr.edu.

Page produced by wwwfoil on Sun Feb 22 1998