Stupid Technical Question: “Mass Insertion”

In reading a theoretical paper on electric dipole moments (well, OK, skimming through it looking for numbers), I ran across several Feynman diagrams with an “X” on one of the particle arrows. The caption contains the presumably-intended-to-be-helpful note “The cross denotes a mass insertion.” I have no idea what that means, and neither does the… Continue reading Stupid Technical Question: “Mass Insertion”

The Witten Thing

I had a bit of a discussion via Twitter with Eric Weinstein yesterday, starting with his statement: Ed Witten has no Nobel Prize. Now tell me again how this era’s physics just feels different because we are too close to it. Basically, he appears to feel that Witten is sufficiently smart that he ought to… Continue reading The Witten Thing

The Anacapa Society

I’ve had a few conversations with other small-college folks about how there ought to be some sort of group within DAMOP for people at small colleges, given how many of us there are who do AMO physics. Nothing has ever come of it, because nobody wants to take on the administrative hassle of organizing such… Continue reading The Anacapa Society