Color me impressed. Our REU students are working on some interesting stuff. From uniquely pancyclic matroids (a matroid generalizes a matrix) to algebraic voting theory (measuring fairness through invariance under group actions) to decompositions of Betti tables (understanding the numerics of free resolutions), we’ve got an excellent crop of projects. On my end, it was challenging to score aspects of the presentations while also paying close attention!
When I was a graduate student, I would go to 3-4 hours of classes a day, teach a couple classes, and even go to an hour or two of seminars. Then I’d go home and do my homework and class prep. That’s the kind of stamina I wish I still had. After a mere 90 minutes of listening intently to math, my brain is still swimming at the end of the day, and I have too many unconnected ideas, questions, and intuitions to do anything useful.