James Riordon’s Crush delivers a compelling, if somewhat fragmented, exploration of gravity’s pervasive role in the universe. The book isn’t just about Newton’s law or Einstein’s relativity; it’s about how this fundamental force dictates the very possibility of life as we know it.
The Unsolved Mystery at the Heart of Everything
For over three centuries, scientists have described what gravity does – how it pulls objects together – but not why it exists. As Riordon points out, even Isaac Newton himself admitted ignorance about the underlying cause. This persistent mystery is the starting point for Crush, a book that doesn’t shy away from the unknown, but instead embraces it as a driving force for deeper understanding. This matters because acknowledging our limits is essential for progress in science. The book weaves through biology, physics, and history, using humor and accessible language to make complex ideas digestible.
Gravity’s Subtle Hand in Everyday Life
Gravity isn’t just about apples falling from trees; it’s woven into the fabric of existence. Riordon highlights how gravity shapes organisms on Earth, dictating where organs sit in a snake’s body and limiting the maximum size of land animals. This isn’t abstract physics; it’s the reason why creatures evolve the way they do. In space, the effects are even more dramatic: microgravity causes astronauts’ bodies to swell, senses to dull, and bones to degrade. The book clearly explains how gravity is not merely a force but a sculptor of life, even in extreme environments.
Beyond Habitable Zones: Life on Rogue Planets?
The book’s most intriguing argument suggests that life may be more likely on rogue planets—those drifting through space without a star. These worlds, though cold, could retain heat from formation and radioactive decay beneath thick ice shells, potentially harboring subsurface oceans for billions of years. Given that rogue planets vastly outnumber those orbiting stars, this shifts the search for extraterrestrial life beyond traditional “habitable zones.” Riordon’s analysis isn’t just speculation; it’s grounded in physics and statistical probability.
Making the Abstract Concrete
Riordon excels at explaining complex physics through relatable metaphors. He uses a kitchen sink to illustrate black holes, connecting abstract frameworks to everyday technologies like GPS and cell phones. This approach doesn’t dumb down the science; it clarifies it. The book also touches on the limits of our understanding: while Newton’s law and Einstein’s relativity are well-established, unifying gravity with quantum mechanics remains a major challenge.
A Fragmented but Compelling Journey
Crush isn’t a perfectly streamlined narrative. Its scope and structure can feel uneven at times, jumping between thought experiments (like calculating how one would die inside a black hole) and broader conceptual discussions. However, this very fragmentation reinforces the book’s core message: gravity is everywhere, shaping everything, and we’ve only scratched the surface of understanding it.
Ultimately, Crush doesn’t offer easy answers but instead leaves readers with a heightened awareness of a force that governs the cosmos – a force that remains both utterly familiar and profoundly mysterious. It’s a reminder that the universe is far stranger, and more wondrous, than we often assume.
