What If Math and Physics Were Fun?

book review by Karen A. Bellenir

What if someone wrote a book that presented math and physics concepts in a fun way, with meticulous explanations, humor, and amazed wonder? Speculation is not required. The feat has been accomplished. What If? Serious Scientific Answers to Absurd Hypothetical Questions, by Randall Munroe, takes a thoughtful, methodical approach to conjuring answers to some bizarre questions.

Munroe, creator of the xkcd comic, takes on queries from readers asking about such things as "What would happen if the earth and all terrestrial objects stopped spinning, but the atmosphere retained its velocity?" The short answer: Terrible things. Or, "What if a glass of water was, all of a sudden, literally half empty?" Literally half empty. Lacking even air. It turns out, the answer depends on which half of the glass—top or bottom—is empty. One creates a bit of turbulence in the water, the other produces a dramatic launch of glass shards.

One intriguing question about draining the earth's oceans receives a two-part answer. The first part discusses what would happen if a drain with an off-world outlet were installed at the lowest point in the Pacific Ocean's Mariana Trench. Apparently a circular, ten-meter portal would lead to a drop in sea levels of less than a centimeter per day. According to Munroe, at this rate draining the world's oceans would take hundreds of thousands of years. But, by positing additional portals, he envisions speeding up the process. Maps depicting the results illustrate how much water the earth's oceans contain and reveal some surprising facts about the topography of the ocean floor.

The second part of the answer considers what humanity might do with all that water. Munroe suggests sending it to Mars, "The Curiosity rover is working so hard to find evidence of water, so I figured we could make things easier for it." Beginning with the Gale Crater in which Curiosity rests, he discusses Martian geography as the imaginary water fills in craters, basins, and the enormous canyon, Valles Marineris. The water keeps rising, covering plateaus and most of the Martian surface. Even after the flow stops, however, Olympus Mons (the largest known volcano in the solar system) still stands ten kilometers above the newly created Martian sea level.

Questions like these—along with many more about such topics as radiation, lightning, air resistance, gravity, and computing power—provides Munroe with plenty of ammunition to prove that math and physics don't have to be boring. Throughout the book's pages, the distinctive stick figures for which he is best known demonstrate processes, achieve the impossible, and meet explosive challenges with aplomb.

Not every budding scientist will need to know how events would unfold if the entirety of a rain storm's water fell in a single giant drop, but curious people everywhere will appreciate how Munroe collects and handles real data to answer such questions. He explains the task of locating pertinent, reliable research from which basic assumptions can be extrapolated and then identifies the physical and mathematical principles that govern outcomes. In short, the book delivers on the promise implicit in its subtitle. It offers serious scientific answers to absurd hypothetical questions.

Pier Press has added What If? Serious Scientific Answers to Absurd Hypothetical Questions, by Randall Munroe, to our bookstore because we believe it can help readers better understand how scientists go about their tasks. It also offers a fun way to learn more about the universe in which we live.