I knew I had a sort of idea what relativity was, but I also knew I didn't actually understand it. I thought it was probably one of the things that I would never get round to understanding. Then I was presented with The Manga Guide to Relativity, and I knew that if anything could explain it, then this book would be that thing.
The guide starts in manga form and tells the story of Student Body President Ruka Minagi who is challenged by Headmaster Iyagi to write a report on relativity over the summer vacation. The beautiful physics teacher Alisa Uraga steps in to teach Minagi all he needs to know to complete the report.
The scenes in the story change seamlessly and often surreally between the classroom and the setting of the examples used to explain the various facets of relativity. Alisa Uraga chooses to explain some of the complicated elements of relativity at the swimming pool while wearing a bikini and other parts while they both float in space. Other characters like Einstein and the Vice Principal who is a dog also step in at times to say hello.
Following a discussion between two characters is actually quite an effective way to learn about a complicated topic. The sections are punctuated by more traditional text book like pages that talk you through the equations and examples in more depth.
The events in the manga that carry the story forward are often bizarre and surreal, but not as surreal as the theory of relativity itself. After reading this book I still wouldn’t pretend to fully understand it, but what I do think I get completely blows my mind.
The example that really blew me away was this:
If astronauts travel to the Andromeda galaxy (approximately 2,500,000 light years away) at 99.999999999 percent of the speed of light, 11.2 years will pass for the one-way trip in the space ship, but nearly 2,500,000 years will pass on earth.
Now that is more bizarre than a school having a dog as a Vice Principal. I’m not going to try and explain it, but time is not the same for everyone. It depends on how fast you’re going and also on gravity. You don’t need to travel faster than the speed of light because as you approach the speed of light distances get shorter and your time slows down. If I understand this correctly the human race could scatter itself through the universe using close to light speed ships. The only thing is that we would also have scattered ourselves through time. You can’t travel huge distances through space without also effectively travelling a huge amount forward in time. That’s not how it worked in Star Trek.
If you want to have a go at understanding relativity then I think this book is an excellent way to do so. If you really want to understand it, you might need to read it more than once. Relativity is a strange and wonderfully weird thing.