How to Build a Time Machine: The Real Science of Time Travel
"In ‘How to Build a Time Machine’ we start each chapter with an affirmation; ‘Yes, time travel is possible …’.  There’s clarification, ‘ifs’, often detailed historic references; consequences; and then the practicalities – at which point you might have the feeling that it’s not possible after all.  But then there’s the ‘Or is it?’, and one cannot but take the bait and turn the page (loop). To name but a few, what does the following have to do with time-travel?: near-light speed travel; an infinitely long cylinder built from dust - or a less ambitious one (!) built from Neutron stars; Wormholes; Paradoxes; Black/White Holes; Antimatter;  Dark Energy…?  If you’re like me when presented with such a list - appetite whet to the point of drooling - this is a book written with you in mind!  One last and very important point: Clegg is both a writer and a Physicist; and it’s as a writer – one who is able to communicate physics to the non-specialist – and that makes this book so very enjoyable.  The hard stuff is there; between the lines; but we’re not asked to deal with it – Clegg leads us through, in his own imitable style! There are just two equations: Einstein’s E=MC2 (of course!), and Maxwell’s – the latter because they’re so “beautifully spare and simple looking”. Perfect."  - Dr. Peet Morris of Oxford University