Are you curious how it all began? The big bang, evolving of stars, time and 3d-space
as properties of our galaxy, string theory and the 11 dimensions?
I can recommend the following series of lectures on the internet on our elegant universe.
In the corresponding book by Brian Greene there is one of the better explanations
of Einsteins theories of special and general relativity, of quantum mechanics and
of string theory. I have written summaries of what I understand of it and of course
in a relative way! Go to summaries.