Symmetry, coordinate systems and the universality of Newton’s laws
.jpeg)
One of the most powerful ideas in physics is that the fundamental laws of nature do not depend on the perspective from which we observe them. An experiment conducted in one orientation should, under the appropriate conditions, produce the same results when the apparatus is rotated. The laws of physics should not favour one direction in space over another. In Lecture 11-3, Rotations , Richard Feynman explores this proposition through a characteristically accessible combination of thought experiments, geometrical reasoning and mathematical demonstration. Following his discussion of translations in the preceding lecture, he now considers whether Newton’s laws remain valid when we change the orientation of our coordinate axes. What makes this lecture particularly interesting is not simply the mathematical result, but the methodology Feynman employs to arrive at it. He begins with an apparently obvious assumption, challenges it with an everyday example, identifies the hidden physical influ...