# Ships, Dinosaurs, and Nuclei: It's the Scales
that Count

##
The question, "Were dinosaurs warm blooded?", is explored by appealing to
scales and dimensional analysis, as is the question, "What was the Royal
Navy's secret weapon in the 19th century?". The question, "What is
a nucleus?" is discussed from the perspective of scales. Chiral symmetry is
introduced by examining the Rutherford experiment, and the influence of that
symmetry on nuclear physics is discussed. Power counting (a form of dimensional
analysis) and "naturalness" are introduced and are used to assess the importance
of many-body forces, and to answer the question, "Is nuclear physics
tractable?". An appeal is made to Gilbert's Law of Magnetism to judge the
complexity of calculations in light nuclei. Recent benchmarks in our
understanding of these systems are reviewed.