Tag Archives: David Roberts

Picard Groups of Moduli Stacks

Posted on April 30, 2020 by Persiflage

Here are some algebraic geometry musings related to the last post, most of which is hopefully correct. Everything below is secretly over \(\mathbf{Z}[1/6]\) but I think one may as well think about what is happening over \(\mathbf{C}\). Warning: I don’t … Continue reading →

Posted in Mathematics | Tagged , , , , , , , , , , | 9 Comments

Chidambaram on genus two curves, II

Posted on April 24, 2020 by Persiflage

We now continue a series of posts on the work of my student Shiva Chidambaram. (Click here for part I.) Today I would like to discuss another project with Shiva that was also joint with David Roberts (no, not David … Continue reading →

Posted in Mathematics, Students, Work of my students | Tagged , , , , , , , , , | 2 Comments

More on Lehmer’s Conjecture

Posted on March 21, 2020 by Persiflage

Lehmer said it was a “natural question” whether there existed an integer such that \(\tau(n)=0\) or not. I’ve wondered a little bit recently about how reasonable this is. (See this post.) The historical context is presumably related to the fact … Continue reading →

Posted in Uncategorized | Tagged , , , , , , , , , | 11 Comments