I agree that these books appear to be excellent introductions to the theory of string theory and its application to an eventual Unified Field theory however diving into the core material without adequate understandings of both some Mathematics and more general Physics is essential to drawing out the correct conclusions in topics as advanced as string theory. I believe without a true understanding of the process of drawing out the principle theorems is futile as it provide insufficient information for learning and will instead spark ludicrous and often times ostentatious presentations of false enlightenment. Such as the example given “for every action alpha I take in an alpha universe, there exists an action beta for an infinite beta universes” or if I eat grapes tomorrow, there is some universe where I ate apples but this is wrong. You cannot think of a parallel universes as separate entities mutually exclusive by everything except chance or choice. Parallel universes are a transcendence to a multiverse free to overlap, attract, repel or usually merge into one another invisible to linear time but obvious to higher dimensions of time like a plane to a cube. Of course you would never realize this until you have studied the material and understood the mathematics properly.

If however you only want an introduction to the topic. I may find lots of intriguing information from a wide variety of sources. For instance, the PBS has released numerous documentaries covering the nature of multiple universes, black holes and even string theory. YouTube also hosts a wide variety of talks aimed for the laymen as well as countless articles published for review from a high school level all the way up to PhD theses on Google books. You can even take micro degrees on coursera following an online classroom as it goes through material designed to engage curiosity and keep the material interesting. They’ll even give you a certificate if you complete the coursework Many of which I might add are free.

Documentaries:

NOVA
https://www.youtube.com/watch?v=UV_X2B5OK1I&list=PLuqWgfVCb3B0YMTTvp9enEddZiOCw5HAd
https://www.youtube.com/watch?v=ZM9fEZhCAr4
https://www.youtube.com/watch?v=-C2uHq3S-lA
https://www.youtube.com/watch?v=DkPH4_Yd4_Q

THROUGH THE WORMHOLE
https://www.youtube.com/watch?v=FMhOJ2wuyUg
https://www.youtube.com/watch?v=kZtEGyI_8jQ
https://www.youtube.com/watch?v=SooOtyXQxgc

STANFORD UNIVERSITY:

Yours truly,
Vainstar