I followed (from afar) the recent presentation at Chicago out of a sense of professional obligation. If we were getting something as important as the CPI wrong, I would want to know (and to do better, whether using gauge theory or whatever other tool!). Weinstein’s theory made no impression on any economist there, as far as I can tell.<p>Few of us know much gauge theory, but he was unable to offer any actual example in the presentation where his theory would get it right and our methods would get it wrong. It is therefore reassuring to see someone who actually knows gauge theory (but not economics) say that even the gauge theory is wrong.