SPECTRUMS

A cheerful, comprehensible and not-too-dumbed-down review of the material universe.

Blatner (The Flying Book: Everything You've Ever Wondered About Flying on Airplanes, 2004, etc.) stresses that we view reality on our own human scale, ignoring the invisible, often bizarre worlds of the very small, very large and very fast. He proceeds to correct this in a thin volume packed with illustrations, diagrams, marginal quotes and innumerable, if often familiar, gee-whiz analogies—e.g., if the Universe begins on January 1, the Earth appears on September 1, humans in the last hour before New Year’s Eve and all recorded history takes up the final 22 seconds of the year. Chapters on “numbers” and “size” demonstrate that the extremes defy common sense without a heavy dose of imagination. Imaginary numbers themselves (such as the square root of negative one) are essential in scientific calculations. Infinity is not a number but an idea. You can’t reach it by counting, and adding any number to infinity equals infinity. As objects get smaller, they become impossible to picture. An electron has no size or specific location; there’s only a probability that it’s present anywhere in the universe. Physicists calculate that no object can be smaller than the “Planck length,” which is extremely small, and no physical law forbids time to run backward, but it never does.

Longtime readers of popular science will find much that is familiar, but this is a fine introduction for beginners.