The universe decoded

The physicist Sean Carroll has embarked on an ambitious experiment with a trilogy that discusses the "Biggest Ideas". Two volumes have been published and both promise to become pop science classics.

- DEVANGSHU DATTA

They bridge an important gap.

Physics used to be called Natural Philosophy back in the day because it offers models of natural processes. However, the laws of physics are expressed as beautiful but complex mathematical equations. Some of us love these equations while being aware that it can be hard work to understand them. Yet, when Stephen Hawking was writing A Brief History of Time, he was famously told his readership would halve with every equation, because many otherwise intelligent readers are afraid of maths.

Dr. Carroll challenges that truism head-on. This series presents physics for "amateurs" with an appropriate leavening of mathematics. The books assume the reader would have some high-school mathematics—enough to follow and understand the physics.

Of necessity, such an approach cannot be rigorous because that would take it into textbook territory with the supplying of proofs of whys and wherefores. A textbook would also present hundreds of problems. These books don't. But the author doesn't ignore the conceptual underpinnings of the equations of physics. So, he threads a very narrow path, where he produces the equations and coherent explanations of their underlying realities, without delving into the precursor maths. For example, Carroll doesn't state the rules of differentiation, or integration, or complex numbers and vector algebra. But he does use the relevant equations and explains the specifics of the derivation of momentum, how differential equations work, and the laws of motion.