Snapshot of my doodles done while talking on the phone to a BBC producer about perhaps appearing in a film discussing anti-gravity*. I explained lots of things, including why General Relativity does not seem to like negative mass, partly because they have something called a “naked singularity”, which is a big problem. Only after the call ended did I recall that in 1999 I co-authored a paper in which we discovered a new mechanism for removing such singularities in some cases, using D-branes in string theory. That’ll be a fun thing to try to explain to camera in simple terms. Hmmm….
*Some blurring of rest of page to remove some not-for-public stuff.