Black Holes, Wormholes and Time Machines [Paperback]

Some parts DO require concentration to get your head around, and I must admit on one or two occasions being slightly lost. Thankfully though 99% of the book was quite easy to follow.

Primarily the book is focused on giving the reader an overview of Einstein's Theories of Relativity, and in particular how these could be applicable to time travel.

My only slight criticism is that the author does seem to concentrate on building/using time machines from a practical viewpoint, as though the reader is a Sc-Fi fan.

Before reading it I thought the universe was born billions of years ago with the Big Bang, and that I was at a certain point in time, and it would carry on ad infinitum after I die. Not necessarily so according to modern physics!

A very small sample of amazing information that I learned was:

Time could start running backwards if the Universe stops expanding and starts contracting.
Time slows down the quicker you go (near the speed of light time almost stops, or speeds up to infinity depending on your viewpoint).
Gravity doesn't pull objects, but bends space itself so objects 'fall' into it.
Gravity bends time and slows it down. Very heavy gravitation can almost stop time.
That the 'present' depends on where you are in space (and your speed), and that all future & past events may co-exist.

The book also touches on Quantum Mechanics, which is even weirder i.e. particles appearing from nowhere and being in 2 places at the same time.

Clear, concise, easy to understand (as easy to understand as four dimensional space-time and parallel universes are), fun to read, funny and the narration, like that of a conversation; absolutely superb. This, along with personal views and experiences, gives this book a unique feel like no other.

What I think is so wonderful about this book is the way in which Mr. Al-Khalili doesn't just simply talk about black holes, wormholes and time machines (!). There's a lot more to it than that. Many other aspects of Physics, from Einstein's theories of relativity, super dense material called cosmic string, to the theory of everything not to mention quantum mechanics are all discussed. It's sheer brilliance the way in which he illustrates how all these things tie-up and are related, through the central focus of the book. Of course, relating everything from atoms to the universe is exactly what Physics is all about, but it is not always easy to see how. Mr. Al-Khalili does this very well.

I also liked the section exploring the science fact behind the science fiction. I was particularly impressed by the profound thought which went into explaining and elaborating upon the Terminator paradox (I'm sure you've all thought about it as well) - if Arnie had succeeded in killing Mrs. Connor, then John would never have been born; but if John hadn't been born, then there would never have been any need to send someone back to kill Mrs. Connor; so Mrs. Connor would not have been killed, and so John would have been born. HEH? This is where parallel universes and quantum mechanics comes in to save the day. This is the first time I've come across this idea, and it's fascinating to say the least. All good stuff!

In the week it took me to read "Black Holes, Wormholes and Time Machines", I spent more time reading than doing my schoolwork! (and a lot of schoolwork is the norm for a hardworking student like myself) - the book is that addictive!

Mr. Al-Khalili has done himself and the university of Surrey proud with an absolutely outstanding book, which is a must read for the interested 'layperson' and Physics student alike.

Mr. Al-Khalili plans to publish another book in about two years time (on quantum mechanics), and I for one can't wait. In the meantime, I think I'll read "Black Holes, Wormholes and Time Machines" over again a couple more times, just for the fun of it!