Suggestions for further reading?

[erby]

I just finished Martin Rees's Book "Just Six Numbers" for an ASTRO class. It was interesting, but he didn't really get into the quant stuff as much as I would have liked. Can anyone suggest further, slightly more quantitative readings that discuss either the cosmological constant, growth of perturbations, or string theory? Thanks in advance...

ERBY /images/graemlins/spade.gif