Probabilistic enumerative geometry over $p$-adic numbers: linear spaces on complete intersections
Annales Henri Lebesgue, Volume 5 (2022), pp. 1329-1360.

### Abstract

We compute the expectation of the number of linear spaces on a random complete intersection in $p$-adic projective space. Here “random” means that the coefficients of the polynomials defining the complete intersections are sampled uniformly from the $p$-adic integers. We show that as the prime $p$ tends to infinity the expected number of linear spaces on a random complete intersection tends to $1$. In the case of the number of lines on a random cubic in three-space and on the intersection of two random quadrics in four-space, we give an explicit formula for this expectation.

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