A reference built from the ground up — the small number of principles the rest of physics is derived from, each with its reasoning, its limits, and its sources.
5 chapters · 36 rules
A first-principles reference, not a textbook to memorize. Every rule is stated plainly, justified from something more basic, and marked with the conditions under which it holds — and the conditions under which it fails.
Students past their first course, engineers who want the why beneath the formula, and anyone who would rather understand ten principles than memorize a hundred equations.
Rebuilt the chapter on symmetry around conservation laws. Added uncertainty and the limits of models.
Initial reference — four chapters, thirty rules, peer-reviewed.
“The insistence on stating limits next to every principle is exactly what students miss elsewhere.”
“Estimate before you calculate has saved me from more bad designs than any tool.”
2 published books reference these rules
