According to the Smithsonian/NASA Astrophysics Data System (what I call ‘adsabs’), I have apparently co-authored a paper with Nobel laureate Frank Wilczek. This, of course, was news to me until I realized that the system’s criteria for ‘paper’ and ‘co-author’ are pretty loose. I wrote a letter to the editor of Physics Today a few years back challenging Wilczek on a point of fundamental physics and Wilczek was given the opportunity to respond. Apparently this qualifies under adsabs as a co-authored paper. So does this mean I can now claim that I have an Erdös number of 4?