The probability that a p-adic random étale algebra is an unramified field
Shmueli, Roy
arXiv preprint arXiv:2211.12995
,
November 2022
We study the random étale algebra generated by a random polynomial with i.i.d. coefficients distributed according to Haar measure normalized on Z_p. We determine the probability that this random algebra is an unramified field, explicitly. In addition, we prove a private case of a conjecture made by Bhargava, Cremona, Fisher, and Gajović. More precisely, we show that this probability is a rational function of p that is invariant under replacing p by 1/p.