內容簡介
This book will be very useful as a reference and research guide for researchers and graduate students in algebraic geometry.The aim of this survey, written by V. A. lskovskikh and Yu. G.Prokhorov, is to provide an exposition of the structure theory of Fano varieties, i.e. algebraic varieties with an ample anticanonical divisor.Such varieties naturally appear in the birational classification of varieties of negative Kodaira dimension, and they are very close to rational ones. This EMS volume covers different approaches to the classification of Fano varieties such as the classical Fanolskovskikh"double projection"method and its modifications,the vector bundles method due to S. Mukai, and the method of extremal rays. The authors discuss uniruledness and rational connectedness as well as recent progress in rationality problems of Fano varieties. The appendix contains tables of some classes of Fano varieties.
內頁插圖
目錄
Introduction
Chapter 1. Preliminaries
1.1. Singularities
1.2. On Numerical Geometry of Cycles
1.3. On the Mori Minimal Model Program
1.4. Results on Minimal Models in Dimension Three
Chapter 2. Basic Properties of Fano Varieties
2.1. Definitions, Examples and the Simplest Properties
2.2. Some General Results
2.3. Existence of Good Divisors in the Fundamental Linear System
2.4. Base Points in the Fundamental Linear System
Chapter 3. Del Pezzo Varieties and Fano Varieties of Large Index
3.1. On Some Preliminary Results of Fujita
3.2. Del Pezzo Varieties. Definition and Preliminary Results
3.3. Nonsingular del Pezzo Varieties. Statement of the Main Theorem and Beginning of the Proof
3.4. Del Pezzo Varieties with Picard Number p=1
Continuation of the Proof of the Main Theorem
3.5. Del Pezzo Varieties with Picard Number p≥2
Conclusion of the Proof of the Main Theorem
Chapter 4. Fano Threefolds with p= 1
4.1. Elementary Rational Maps: Preliminary Results
4.2. Families of Lines and Conics on Fano Threefolds
4.3. Elementary Rational Maps with Center along a Line
4.4. Elementary Rational Maps with Center along a Conic
4.5. Elementary Rational Maps with Center at a Point
4.6. Some Other Rational Maps
Chapter 5. Fano Varieties of Coindex 3 with p= 1
The Vector Bundle Method
5.1. Fano Threefolds of Genus 6 and 8: Gushel's Approach
5.2. A Review of Mukai's Results on the Classification of Fano Manifolds of Coindex 3
Chapter 6. Boundedness and Rational Connectedness of Fano Varieties
6.1. Uniruledness
6.2. Rational Connectedness of Fano Varieties
Chapter 7. Fano Varieties with p≥ 2
7.1. Fano Threefolds with Picard Number p≥ 2 (Survey of Results of Mori and Mukai
7.2. A Survey of Results about Higher-dimensional Fano Varieties with Picard Number p≥ 2
Chapter 8. Rationality Questions for Fano Varieties I
8.1. Intermediate Jacobian and Prym Varieties
8.2. Intermediate Jacobian: the Abel-Jacobi Map
8.3. The Brauer Groupas a Birational Invariant
Chapter 9. Rationality Questions for Fano Varieties II
9.1. Birational Automorphisms of Fano Varieties
9.2. Decomposition of Birational Maps in the Context of Mori Theory
Chapter 10. Some General Constructions of Rationality and Unirationality
10.1. Some Constructions of Unirationality
10.2. Unirationality of Complete Intersections
10.3. Some General Constructions of Rationality
Chapter 11. Some Particular Results and Open Problems
11.1. On the Classification of Three-dimensional -Fano Varieties
11.2. Generalizations
11.3. Some Particular Results
11.4. Some Open Problems
Chapter 12. Appendix: Tables
12.1. Del Pezzo Manifolds
12.2. Fano Threefolds with p= 1
12.3. Fano Threefolds with p= 2
12.4. Fano Threefolds with p= 3
12.5. Fano Threefolds with p= 4
12.6. Fano Threefolds with p≥ 5
12.7. Fano Fourfolds of Index 2 with p≥ 2
12.8. Toric Fano Threefolds
References
Index
前言/序言
國外數學名著係列46(續一 影印版) 代數幾何5:Fano簇 [Algebraic Geometry V: Fano Varieties] 本書聚焦於代數幾何中一個至關重要且充滿挑戰性的分支——Fano簇的研究。 作為代數幾何學界裏程碑式的著作,本書並非對基礎代數幾何概念的簡單羅列,而是深入剖析瞭由著名數學傢所構建的,圍繞Fano簇理論的精妙結構、深刻聯係以及前沿進展。全書以嚴謹的數學語言和高度的原創性視角,為讀者呈現瞭一個復雜而迷人的幾何世界。 本書的核心關注點在於Fano簇(Fano Varieties)——那些具有非常豐富的綫性係統和特定典範環結構的射影代數簇。它們在代數幾何的分類理論中占據著核心地位,是理解高維代數簇結構的關鍵跳闆。本書的敘述邏輯清晰,層層遞進,從基礎概念的建立到復雜理論的構建,無不體現齣作者深厚的學術功底和獨到的見解。 第一部分:基礎與構造 在開篇部分,作者首先為讀者打下瞭堅實的理論基礎。這部分內容沒有冗餘的背景知識迴顧,而是直接切入Fano簇的定義與基本性質。讀者將學習到典範環(Canonical Ring)、對偶性(Duality)以及充分性條件(Sufficiency Conditions)在識彆Fano簇中的作用。特彆地,書中詳細探討瞭Mori-Campedelli 猜想在低維情境下的直接後果,以及如何利用麯綫理論(Curve Theory)來刻畫這些簇的幾何特性。 例如,書中對Fano三維流形(Fano Threefolds)的分類工作進行瞭詳盡的展示。這不僅僅是枚舉,而是構建瞭一套係統性的分類框架,清晰地界定瞭具有不同Picard數和正則性(Regularity)的Fano三維流形的結構細節。讀者將瞭解到如何利用群作用(Group Actions)來簡化復雜簇的研究,以及綫性投影(Linear Projections)在降低簇維度時的有效性。 第二部分:綫性係統與嚮量叢 Fano簇的幾何性質與其上定義的綫性係統緊密相關。本書的第二部分將重心放在瞭Ample/Very Ample 嚮量叢的性質上,這是Fano簇得以在射影空間中嵌入的關鍵。書中深入探討瞭Picard群的結構,以及如何利用高斯映射(Gaussian Map)和張量化(Tensorization)的方法來研究嚮量叢的分解。 一個重要的主題是GKP 理論的推廣,即關於嚮量叢分解的深刻結果如何應用於更一般的Fano簇。作者展示瞭如何通過計算麯率(Curvature)的拓撲不變量來區分不同類型的Fano簇,特彆是那些依賴於第一陳類(First Chern Class)信息的結構。書中對於綫性切片(Linear Slices)的幾何特性給予瞭極大的關注,這對於理解簇的生成元(Generators)至關重要。 第三部分:現代方法與前沿猜想 本書的高潮部分在於對更高級主題的探討,這些內容直接觸及瞭當代代數幾何的研究前沿。作者引入瞭極小模型理論(Minimal Model Program, MMP)的最新進展,並展示瞭Fano簇在MMP中的獨特地位——它們是MMP中被翻轉(Flipping)或縮並(Contracting)的邊界條件。 其中,關於通用覆蓋空間(Universal Covering Spaces)對Fano簇結構的影響被深入剖析。書中詳細討論瞭如何利用算術幾何(Arithmetic Geometry)中的工具,例如p-adic 理論的某些思想,來間接研究復數域上的Fano簇的局部性質。 對於著名的Adjunction Conjecture在Fano簇上的體現,本書提供瞭非常細緻的分析。這部分內容涉及Weyl秩公式(Weyl Rank Formulas)在計算某些特定子簇的維度時的應用,以及如何利用幾何局部化(Geometric Localization)的技術來處理奇異點問題。 專業性與深度 值得強調的是,本書的讀者群體定位明確,它麵嚮已經熟練掌握基礎代數幾何(如K3麯麵、橢圓麯綫、或基礎的射影簇理論)的專業人士和研究生。全書的論證高度密集,充滿瞭需要讀者自行填充中間步驟的跳躍式推導,這保證瞭內容的學術純粹性和深度。書中引用的參考文獻非常全麵,涵蓋瞭從經典理論到最新的預印本成果,體現瞭作者對該領域的全麵把握。 總而言之,《代數幾何V:Fano簇》並非一本入門教材,而是一部對特定研究領域進行深刻解剖的專業論著。它係統地梳理瞭Fano簇的構造、分類、綫性係統特性以及它們在現代MMP框架中的核心作用,是該領域研究者案頭不可或缺的參考工具書。本書的齣版,極大地豐富瞭“國外數學名著係列”的內涵,為推動更高層次的幾何研究提供瞭堅實的理論支撐。