GordonE44 said:
... I am interested in cosmology too as I like space. I am thinking of getting Endless Universe: Beyond the Big Bang -- Rewriting Cosmic History because I got a little information about the ekpyrotic theory from my String theory for dummies book and was interested in learning more. What else should I get?...
In case you would like a completely different viewpoint, I will present a countervailing suggestion or two. You are the one choosing.
You say you might get (or have already) Steinhardt Turok's book about the clashing brane cosmology. Ekpyrotic, cyclic, variations on that. I don't think the odds are high that brane-clash cosmo will last. Interest in it has been waning since 2005 or so.
Both guys are very highly respected, lots of prestige (Steinhardt at Princeton, Turok at Perimeter Institute, where he is director). Their clash-brane cosmo ideas are intelligent, interesting, original and are always MENTIONED. But almost nobody pursues them any more.
They originally thought up brane-clash as an alternative to inflation (to try and answer the same riddles that inflation solves) because Steinhardt doesn't think inflation is compatible with compact-extra-dimension superstring!
According to him you likely have to give up either one or the other. Give up string, or give up inflation.
Now it looks to me as if he is leaning more towards accepting inflation and has become less interested in string.
In other words, it looks like Steinhardt has moved on somewhat from where he was when he and Turok were actively investigating ekpyrotic
say around 2005. (The appearance of their popularization means nothing. Pops are a different business from serious research and have their own schedule.

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What I would suggest you do, in fact, is not bother with the Steinhardt Turok book (which is popularization of an older idea of declining interest.)
I would suggest first simply read Renate Loll's SciAm article on quantum gravity (QG). I keep a link handy in my signature. It's free. Let me know if the link doesn't work.
Don't misunderstand me. I don't pick QG winners and I don't suggest Renate Loll's approach is going to win the QG sweepstakes. We don't know whose will.
The point is that she is a good writer and she illustrates how someone can address QG from a direction entirely different from string's.
My impression is that the String for Dummies book mentions some interesting alternatives (like Loll's, and also like LQG) but does not do them justice.
If you actually do read Loll's QG SciAm article from 2008 and are at all interested, then come back with more questions. I might, or somebody might, have some further suggestions of things to read. If you don't find Loll's article interesting, then it would be a waste of time for me to suggest further stuff because it probably wouldn't be to your taste.