Thank you so much for your post. I’m about to start studying for the GRE, and I was wondering, what courses did you take and what books did you use? You seem to have some great ideas on how to study, and I thought you would know the best courses or books. Thank you!

]]>Try computing the size of the observable universe in cubic Planck volumes, it’s on the

order of 10^128 or something. A cubic Planck volume is really small about 10^-35 cubic meter. ]]>

Thank you for your note about the prime numbers and perfact numbers. Follwing your explanations and questions I could step into a number theory and realized it is an interesting subject. ]]>

No one is going to think you a fool… you got into graduate school. ]]>