TAILIEUCHUNG - Đề tài " Ramification theory for varieties over a perfect field "

For an -adic sheaf on a variety of arbitrary dimension over a perfect field, we define the Swan class measuring the wild ramification as a 0-cycle class supported on the ramification locus. We prove a Lefschetz trace formula for open varieties and a generalization of the Grothendieck-Ogg-Shararevich formula using the Swan class. Let F be a perfect field and U be a separated and smooth scheme of finite type purely of dimension d over F . In this paper, we study ramification of a finite ´tale scheme V over U along the boundary, by introducing a map (). | Annals of Mathematics Ramification theory for varieties over a perfect field By Kazuya Kato and Takeshi Saito Annals of Mathematics 168 2008 33 96 Ramification theory for varieties over a perfect field By KAZuyA Kato and Takeshi Saito Abstract For an -adic sheaf on a variety of arbitrary dimension over a perfect field we define the Swan class measuring the wild ramification as a 0-cycle class supported on the ramification locus. We prove a Lefschetz trace formula for open varieties and a generalization of the Grothendieck-Ogg-Shararevich formula using the Swan class. Let F be a perfect field and U be a separated and smooth scheme of finite type purely of dimension d over F. In this paper we study ramification of a finite etale scheme V over U along the boundary by introducing a map below. We put CH0 V V lim CH0 Y V where Y runs compactifications of V and the transition maps are proper push-forwards Definition . The degree maps CH0 Y V Z induce a map deg CH0 V V Z. The fiber product V u V is smooth purely of dimension d and the diagonal Ay V V u V is an open and closed immersion. Thus the complement V u V Ay is also smooth purely of dimension d and the Chow group CHd V u V Ay is the free abelian group generated by the classes of connected components of V u V not contained in Ay. If U is connected and if V U is a Galois covering the scheme V u V is the disjoint union of the graphs rơ for ơ E G Gal V U and the group CHd V u V Ay is identified with the free abelian group generated by G 1 . The intersection of a connected component of V u V Ay with Ay is empty. However we define the intersection product with the logarithmic diagonal Ay log CHd V U V Ay --- CH0 V V Z Q using log product and alteration Theorem . The aim of this paper is to show that the map gives generalizations to an arbitrary dimension of the classical invariants of wild ramification of f V U. The image of the map is in fact supported on the wild ramification locus Proposition .

TỪ KHÓA LIÊN QUAN
TAILIEUCHUNG - Chia sẻ tài liệu không giới hạn
Địa chỉ : 444 Hoang Hoa Tham, Hanoi, Viet Nam
Website : tailieuchung.com
Email : tailieuchung20@gmail.com
Tailieuchung.com là thư viện tài liệu trực tuyến, nơi chia sẽ trao đổi hàng triệu tài liệu như luận văn đồ án, sách, giáo trình, đề thi.
Chúng tôi không chịu trách nhiệm liên quan đến các vấn đề bản quyền nội dung tài liệu được thành viên tự nguyện đăng tải lên, nếu phát hiện thấy tài liệu xấu hoặc tài liệu có bản quyền xin hãy email cho chúng tôi.
Đã phát hiện trình chặn quảng cáo AdBlock
Trang web này phụ thuộc vào doanh thu từ số lần hiển thị quảng cáo để tồn tại. Vui lòng tắt trình chặn quảng cáo của bạn hoặc tạm dừng tính năng chặn quảng cáo cho trang web này.