I’m at a conference in Montreal this week, so it’s going to be a short post. The University of Montreal’s Centre de Recherches Mathématiques has been holding a program on the various hidden symmetries of N=4 super Yang-Mills since the beginning of the summer. This week is the amplitudes-focused part of the program, so they’ve brought in a bunch of amplitudes-folks from around the world, myself included.

It’s been great hanging out with fellow members of my sub-field, as always, both at the conference and at dinner afterwards. Over possibly too much wine I heard stories of the heady days of 2007, when James Drummond and Johannes Henn first discovered one of the most powerful symmetries of N=4 super Yang-Mills (a duality called dual conformal invariance) and Andrew Hodges showed off the power of a set of funky variables called twistors. It’s amazing to me how fast the field moves, sometimes: by the time I started doing amplitudes work in 2011 these ideas were the bedrock of the field. History operates on different scales, and in amplitudes a few decades have played host to an enormous amount of progress.

History in the real world can move surprisingly fast too. After seeing cathedrals in Zurich that date back to the medieval era, I was surprised when the majestic basilica overlooking Montreal turned out to be less than a century old.

In retrospect the light-up cross should have made it obvious.