DO ALIENS SPEAK PHYSICS?

The universe as we may never know it.

If aliens were to visit from some far-off planet, might they come bearing the secrets of the cosmos? Surely any creature capable of intergalactic travel knows more about physics than we do. Maybe they evolved to hear space-time curvature or taste light or feel dark matter. Whiteson, a particle physicist, and Warner, a cartoonist, imagine such wild possibilities in this deceptively entertaining book. It’s written in casual prose (“There are many potential benefits to aliens’ arriving, starting with getting the day off from work”), peppered with goofy cartoons (a cat presents the catnip theory of the universe), and interspersed with snippets of sci-fi (an alien race communicates using “gestures coordinated with facial color changes”), but beneath the cutesy presentation is a profound philosophical question. Does science capture objective features of the world, or does it reveal our own biological, cultural, and historical whims? We like to think of physics as an expression of ultimate truth, written in the universal language of mathematics—a language we would inevitably share with those little green men. After all, whether you speak English, Chinese, or Klingon, one plus one still equals two. Or does it? “What if aliens arrive sloshing around in plasma environments where these distinctions are so fuzzy that the concept of a countable individual doesn’t exist and counting and arithmetic are unknown to them?” the authors ask. This is the deep insight of the book: The way we carve up reality—into objects, numbers, words, stories—may be as much a reflection of ourselves as it is of the universe. At times the writing veers glib (as when they describe Carl Sagan as an “influencer”); occasionally, it’s wonderful: “Our words are local and restless, changing over time as language wriggles into new contexts.” But always, it’s chock-full of insights, from the physics of emergence to the limits of logic. That’s the power, it seems, of little green science.

Charming, funny, and surprisingly philosophical speculations about alien science raise deep questions about science itself.