Review by Joshua Jackson, North Carolina State University
Wizards, Aliens, and Starships: Physics and Math in Fantasy and Science Fiction
Charles L. Adler
Princeton, New Jersey: University of Princeton Press, 2014. 392. Non-fiction.
Since time immemorial (ok, since I was 7 or 8), science fiction has been the main staple in my book diet. I have traversed billions upon billions of miles, encountered the riches of this universe, and mourned some of the most heroic men, women, and aliens I'll ever meet. I was reticent at first to review Charles L. Adler's book Wizards, Aliens, and Starships: Physics and Math in Fantasy and Science Fiction (Princeton Press, 2014); I was certain he going to invalidate the adventures I've had, and with math, no less! Instead, it made me a more aware reader of science fiction. I will treat this book in the best way I can: with minimal math and the same frenetic energy Adler imparted.
Within the first few sentences of the introductory chapter, Adler states that "Almost any science fiction story has a lot of incorrect science (p. 2)." Adler's goal for this text, then, is "…to discuss science, particularly the physics and mathematics, that [go] into writing hard science fiction (p. 2)." The rest of the first chapters goes over the main working assumptions that the author makes, and broaches the basic physics and math that the reader needs a vague familiarity with to get the most out of this text.
Chapters 2-4 comprise the section called "Potter Physics." This section covers the viability of magic worlds, such as the Harry Potter world and its denizens. The laws of conservation of mass and momentum make up the bulk of the arguments for the first chapter; things such as dissipation, or "…the ability to vanish from one spot and reappear instantly in another (p. 16)" and how thermodynamics would, in most cases, limit or completely refute the practicality of magic in any circumstance. Adler also discusses why Hogwarts would actually be much darker than it is portrayed in the movies or in the books. The luminosity of a single candle, Adler states in table 3.1 (p. 34) is 12 lumins (lm), then estimates that the Great Hall from the Harry Potter series is approximately 700 m2 (p. 34). From those measurements, he estimates it would be around $10 million/year to light the entire castle (p. 36).
Chapters 5-13 comprise the largest section of the book called "Space Travel." Adler starts by setting the stage for the two recurring problems that the reader will encounter time and again in the text: energy and cost (p. 61). Current space travel "…has a cost of about $450 million (p. 80)." Because of this enormous price tag ("…$130,000 for an orbital vacation (per person) (p. 84)…"), compounded with the roughly 1/60 chance of death in space travel (p. 81), Adler makes a cogent argument for why one might, instead, just take a vacation to Bermuda instead. The concept of massive orbiting entities such as a space colony, or a space elevator, is an alluring one, too: a place for deep space probes to launch; large, undiluted solar panels; growing large, flawless industrial crystals; space tourism (p. 87). Unfortunately, energy and material concerns seem to be where the majority of the problems with large space structures like space colonies and space elevators lie; issues of building structures that won't break apart, establishing and powering a renewable ecology, providing gravity and an atmosphere to the inhabitants, and, above all, feeding all the inhabitants.
Adler considers some popular propulsion examples including an antimatter propulsion system. Star Trek did it, right? Again, it comes down to money. "There's a tendency for nonphysicists to somehow think that antimatter is exotic, or a theory that hasn't been proven yet. All these notions are untrue… (p. 166)." But how much does it cost? Adler estimates the cost of antimatter production to be 107 $/mg. A typical payload for a spaceship is around 10,000 kg. We have to add a magnitude of 4 to the 10,000 kg payload to account for acceleration going, deceleration arriving, acceleration leaving, and deceleration coming back. We end up with a price-tag of $1e+18 for a trip with an antimatter engine. We also must consider that "…if we launch anywhere near Earth's orbit, we will likely destroy Earth's ecology, especially if we consider that… all of the energy is being delivered in the form of high-energy gamma rays… (p.174)."
Relativity really puts a damper on things. "From our best knowledge of physics today, nothing can go faster than the speed of light (p. 178)." But… Star Trek! "Faster-than-light travel and time travel are both impossible (p. 188)." Adler discusses the far-flung ideology of using tachyons, quantum entanglement, or casually just folding space and going through a wormhole. As far as any of these go, "Tachyons are completely hypothetical…," quantum entanglement isn't feasible because "…wave function collapse cannot transmit information of energy…," and wormholes… well, according to general relativity, "space behaves… like a rubber sheet… there is nothing to prevent the sheet from being bent so that two points, although far away… are close in a direction perpendicular to the sheet…" (pp. 189-190) but, if you can't already guess, energy and materials (particularly the need for "…things almost as exotic as the ingredients used in the myth to keep wormholes open (p. 202)…") are prohibitive, to say the least.
Chapters 14-16 comprise the section called "Worlds and Aliens." Adler is explicit in stating that he will only examine Earth-like planets, and humanoid aliens (p. 218). Atmospheric conditions, whether a planet lies in its star's habitable zone, and what type of star said planet orbits all play important roles in determining the habitability of the planet, or what we understand as habitability. But even if we find an exoplanet in its star's habitable zone, how can we determine if there is life? "The answer depends on whether we can measure the composition of any atmosphere the planet has in a transit (p. 250)." Once we find a planet that we think may have a shot at harboring intelligent life, how do we talk to them? Or… should we? "Historical meetings between technologically advanced civilizations and less advanced ones in Earth's own history underscore the dangers of such contact (p. 259)."
Chapters 17-21 comprise the final section called "Year Googol." The future of the human race is tenuous. Can we fix global warming? "[Though] the effects can be partially mitigated…It is inevitable that the world's temperature will rise significantly over the next century. The disagreements are only about… how much, which parts of the world… and so on (p. 279)." Is it feasible to, instead of fixing the world we have terraform a planet like Mars? It boils down to time and, you guessed it, energy. Seeding a planet by "…releasing genetically engineered extremophilic bacteria or plants into the Martian environment… (p. 296)" would cause a chain reaction to raise levels of CO2, which in turn would make Mars' thin environment more Earth-like. And at the cost of just roughly 1,000 years and $1011 (p. 301), or about $100 billion/year, who is going to foot that bill? "If we were to look to private industry to pay for this… how is terraforming Mars going to turn a profit? Damned if I know… there is nothing, and I mean nothing that we could manufacture on Mars and ship to earth that would not be infinitely cheaper to produce here (p.301)."
Adler finishes the text by examining a paper from Nokolai Kardeshev that "…[proposes] a typology of advanced civilizations… (p. 327)" and what this means for humanity a Googol years out. Current, we are a Type 0.7 Civilization; our current world energy usage rate is about 1012 W (p. 327). A Type 1 civilization harnesses the energy resources available to the entire planet and "…has an average power usage of… 1,000 times the amount of power consumed by the world today (p. 328)." As our energy usage and production ability increases towards that Type 1 classification, everything that Adler has examined in the book starts to become more and more feasible: energy costs will drop, material sciences will accommodate the rise in energy usage, and our understanding of quantum mechanics will be fuller. Exponential growth in our scientific understanding and energy production and usage could mean that, a Googol years out, once all the stars are long dead, we may be dropping trash into a black hole to harvest the energy (p. 344)!
In the scope of this book, section one is out-of-place; tacked-on, almost. This is the only portion of the book that covers anything in the realm of "fantasy," and the topics covered don't contribute in any meaningful way to the building topical framework of the book. The crux of the rest of the issues in this text center around time, energy, and money, so the math and physics covered here have limited scope beyond this section.
Aside from these small issues, I thoroughly enjoyed the text; it gave me the tools to critically read science fiction in a way that I never thought I would be able to: by looking at a concept in a science fiction book and knowing whether it is founded on sound science, and if it is, how long until we today can get there. And while I am not the target audience to parse the math and science that went into the book, Adler did a fantastic job of putting those concepts in terms that science fiction fans would understand, regardless of well math-and-science-savvy they were.
Joshua Jackson is a PhD student at North Carolina State University. His concentration is communication constructs in virtual worlds. His research centers around Massive Multiplayer Online games.
© 2016 Joshua Jackson, used by permission