List of Figures

• 1.1. Hubble Space Telescope image of a hot white dwarf
• 1.2. Sample light curve of the pulsating white dwarf GD 358
• 1.3. The parallel computer built and used for this thesis

• 2.1. The master computer surrounded by 64 slave nodes
• 2.2. Darwin, the master computer.
• 2.3. A view inside one of the metacomputer nodes

• 3.1. Flow chart for the parallel fitness evaluation subroutine
• 3.2. Flow chart for the slave program

• 4.1. Linear cut imposed on the helium layer mass
• 4.2. Two determinations of the noise on pulsation frequencies
• 4.3. General features of the 3-dimensional parameter-space
• 4.4. Parameter-space for GD 358 using various core compositions
• 4.5. Uncertainty on the central oxygen mass fraction in GD 358

• 5.1. Sensitivity of pulsation periods to the deep internal structure
• 5.2. The Brunt-Väisälä frequency for various chemical profiles
• 5.3. GD 358 pulsation periods with various best-fit models
• 5.4. Internal chemical profiles of the best-fit models to GD 358

• A.1. The Whole Earth Telescope