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When he announced that he was finally writing a book, I trusted that Randall Munroe — former NASA roboticist and creator of the geek culture icon xkcd — would use his trademark style to communicate science both odd and profound in a fun, digestible way. And in What If?: Serious Scientific Answers to Absurd Hypothetical Questions, he absolutely delivers.

What If? is a fast, engrossing read. After you get accustomed to Munroe’s rapid-fire delivery and hilariously nochalant throw-away lines (“Assuming you’re a reasonably good swimmer, you could probably survive treading water from 10 to 40 hours. At that point, you would black out from fatigue and drown. This is also true for a pool without nuclear fuel at the bottom”), you are free to take dozens of odd journeys with him and giggle while you learn.

And learn you will. There is a sort of joy in getting real answers to the admittedly ridiculous questions Munroe is sent every day (many of the questions in What If? have been republished from his blog of the same name). For example, yes, you could swim in a pool of spent nuclear fuel rods. In fact, do it right and you’d actually get less radiation than someone standing at the surface! And if a physicist pessimist made a glass literally half-empty (one half is a vacuum), the glass would rocket itself into your ceiling, which Munroe examines millisecond by millisecond.

The charm of What If? lies in the ease Munroe has jumping past intensely interesting conclusions and onto his next thought, tangent, or consequence. It’s as if Munroe is a unseen stage technician pulling back the curtain — the answers were always there, we just needed someone who knew how to show us. Even he seems surprised at what he finds.

If you were a reader of either xkcd the webcomic or the What If? blog, then the book should be a breeze and a treat for you. The writing is blunt yet meaningful and What If? is of course filled with Munroe’s trademark stick-figure illustrations. However, taking everything offline does have its drawbacks. For example, while a few made it into the book, the famous scroll-over texts — a sentence of two of snark or clarification that would appear if you held your cursor over almost any xkcd drawing — is obviously not present in the book. And though What If? has a references section, not being able to hyperlink in text does give the reader even less of a chance to figure out just where Munroe is getting his answers from.

These quibbles don’t take away from the love and wonder for math and science that Munroe expertly channels. Each page will treat old and new audiences alike to delightful tidbits of science that shake out from Munroe’s analyses. Did you know that Star Wars‘ “Death Star” effectively gave Alderaan a magnitude 15 earthquake? How about that you could feasibly make a jetpack out of downwards-firing machine guns? The bizarre and often disturbing questions that Munroe doesn’t answer might be even more fun to read (“How fast would a human have to run in order to be cut in half at the bellybutton by a cheese-cutting wire?”), which he features in a handful of “Weird (and Worrying) Questions from the What If Inbox” sections.

And don’t worry, the “citation needed” gags are back in full force here (“Falling from great heights is dangerous [citation needed]“).

Even the book itself oozes xkcd‘s style. The inside of the book’s jacket is actually a full-size infographic of what the Earth would look like if the oceans were drained from the bottom of the Marianas trench. The back of the book has no blurbs or praise from other authors — it’s a collection of things that you might want to know before buying the book (“Humans can’t digest the cellulose in paper, but if we could, eating this book would give you about 2,300 calories”). Thanks Randall.

I said that I had to trust Munroe because the first thing strikes you about his witty, concise prose is that although he obviously has enough intellectual chops to explain the various scientific concepts tackled in his questions, What If? is not a textbook. Munroe simply states that when throwing a baseball at light-speed there would be an x-ray shockwave expanding outwards from a fireball of plasma, and quickly moves on. He is answering the question after all, but if you are looking for classroom-style descriptions of what Munroe is talking about, you’re out of luck.

But that is the best part. Long-time readers of xkcd know just how intelligent Munroe is, and new audiences will quickly find out. Heck, there is a whole website dedicated to explaining the math and science in his comics. What If? is in this way perfectly accessible and inaccessible — light enough to entertain you but dense enough to throw you down a rabbit hole of fascinating science one brief chapter at a time. If you are willing to go along with Munroe’s assumptions, guesstimates, and caveats (of which there are many), you are in for a wild intellectual ride [no citation needed].

What If?: Serious Scientific Answers to Absurd Hypothetical Questions is available in the US today and in the UK on Thursday.

Kyle Hill is the Chief Science Officer of the Nerdist enterprise. Follow the continued geekery on Twitter @Sci_Phile.

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