Game of Thronesmight be loosely based on the 100 Years' War, but it's not set on Earth: it's a bigger planet with less metal, a longer year and, of course, magic and dragons. But the books and the TV series are long enough and detailed enough that this chatty but dense book can work out a lot about the science that would underpin the world. Westeros, George R R Martin says, is the size of North and South America; it also fits in one hemisphere, which gives you a way to guess the size of the planet. There are copious other details on lots of other areas.
In Fire, Ice and PhysicsRebecca C Thompson uses these details to dig in to how everything from winter to dragons work in Westeros. Along the way you learn a lot about meteorology, astronomy, physics and biology on earth too.
The book is framed as a series of questions. Winter, they warn, is coming. Why is winter coming? Is it because Westeros orbits two stars, or a star and a black hole, or because the second moon cracked open like an egg, or because the planet wobbles on its axis like an irregular top? Thompson covers the science behind all those possibilities, but doesn't settle on any of them as the perfect solution.
Do you need magic to have an ice wall? Turns out yes, because without magic it would wear down to an ice hummock. But along the way we learn about different kinds of ice, fluids that turn solid when you hit them, and the abortive World War 2 attempt to make artificial islands out of frozen wood pulp. Can you survive on a frozen lake? Probably not, but wearing fur helps because polar bear fur is translucent and reflects infrared, trapping radiated heat, unlike modern materials that keep you warm when you're standing still but cool when you're moving. You should wear a hat not because of the much-misunderstood study about losing heat from your head but because unlike baring any other part of your body, you don't shiver when your head is bare so you lose heat without compensating for it.
The lengthy discussion of zombies attempts to explain which parts of Wight brains will still work and looks at the rather disturbing details of zombie ants and crabs, plus human decomposition — the Wights are lucky it's cold beyond the wall, Thompson notes, comparing it to the 'rainbow valley' on Everest named for the brightly coloured parkas on the corpses of climbers. There's a surprising amount of research on how zombieism spreads for her to cite, and we get a definitive answer to one question: the zombie dragon would be easy to drag because it would float.
There's a lot about steel and smelting and rather too much on the arguments about the lost techniques for creating Damascene steel, on which the dragon-forged Valyrian steel of Westeros is clearly based. Along with the advanced chemistry you'll learn that the Titanic sunk because you shouldn't mix steel hulls and icy water, and that you can't cast a sword in a mould, no matter how good it looks on TV.
Dragons, Thompson concludes, are warm blooded and most like armadillos with bat wings (which are so efficient they're inspiring next-generation drones) -- or maybe pterosaur wings which, despite years of scientists arguing couldn't fly, actually did. Like bats, dragons can also walk on their wings and probably use their flame to help generate lift with thermals, except that that their bones would probably have broken on take-off (unless those are magical too).
You find out just how little we know about glass -- and that you can still buy uranium online. Dragonglass is an obsidian that probably comes from dragons melting granite — and yes, dragon flame can melt stone, as well as metal, even though it looks like dragons shouldn't be able to produce flame at all. Again, there's plenty of chemistry to cover: solids don't burn, the vapour they give off when they get hot does (and rusting is actually slow-motion fire). Dragon flame can't be powder like flour or cornstarch otherwise it wouldn't explode the way it does when you stick a spear in a dragon's neck, and it can't be methane because, unlike cows, dragons don't eat grass -- so it's probably rocket fuel. But as that would burn the dragon's throat as it comes out, either the fire or the throat is again magic.
We don't know the exact recipe of the ancient Greek fire -- which is likely what wildfire is — but there is a fun discussion of several things it isn't. Along the way Thompson looks at various other things that catch fire. The chapter on sailing is rather less exciting than the rest of the book, the chapter on the effect of inbreeding will teach you a fair bit of genetics, and the chapter on the various forms of execution and murder in Game of Thrones is gruesome -- and perhaps a little too full of the author's own discomfort with how they would all feel as they died.
In general, the chattiness of this book doesn't always work and the authorial asides are not quite as funny as they're intended to be. That said, we enjoyed the advice on avoiding tedious conversations on planes by opening a document on beheading.
The biggest problem with Fire, Ice and Physics is that the attempts to find scientific explanations for the phenomena of Westeros tend to go around in circles. There simply aren't definitive answers to most of these debates and the fun is in having the debate, but the author's desire to reach a conclusion anyway makes some chapters unsatisfying despite the wealth of details and facts. In the end, this is more an explanation of how things like those in Westeros work in this world than a coherent science of that fictional world itself, where (as Martin has said in the past) the reason for how something works might be 'that's just the way it is'.