Abstract This article reports on an approach to point counting on algebraic varieties over finite fields that is based on a detailed investigation of the 2-adic orthogonal group. Combining the new approach with a p -adic method, we count the number of points on some K 3 surfaces over the field $$\mathbb {F}_{\!p}$$ F p , for all primes $$p < 10^8$$ p < 10 8 .
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Regular integral models for Shimura varieties of orthogonal type
We consider Shimura varieties for orthogonal or spin groups acting on hermitian symmetric domains of type IV. We give regular $$p$$ -adic integral models for these varieties over odd primes $$p$$ at which the level subgroup is the connected stabilizer of a vertex lattice in the orthogonal space. Our construction is obtained by combining results of Kisin and the first author with an explicit presentation and resolution of a corresponding local model.
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- Award ID(s):
- 2100743
- PAR ID:
- 10411243
- Date Published:
- Journal Name:
- Compositio Mathematica
- Volume:
- 158
- Issue:
- 4
- ISSN:
- 0010-437X
- Page Range / eLocation ID:
- 831 to 867
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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