Publications Meetings The Profession Membership Programs Math Samplings Policy & Advocacy In the News About the AMS
|
   
Available in electronic format
Available in print format
Transactions of the American Mathematical Society
Transactions of the American Mathematical Society
ISSN 1088-6850(e) ISSN 0002-9947(p)

     

Degenerations of rationally connected varieties

Author(s): Amit Hogadi; Chenyang Xu
Journal: Trans. Amer. Math. Soc. 361 (2009), 3931-3949.
MSC (2000): Primary 14J26, 14J45; Secondary 14E30, 14G27
Posted: March 3, 2009
MathSciNet review: 2491906
Retrieve article in: PDF

Abstract | References | Similar articles | Additional information

Abstract: We prove that a degeneration of rationally connected varieties over a field of characteristic zero always contains a geometrically irreducible subvariety which is rationally connected.


References:

[Am04]
Ambro, F.; Shokurov's boundary property. J. Differential Geom. 67 (2004), no. 2, 229-255. MR 2153078 (2006d:14033)

[BPV84]
Barth, W.; Peters, C.; Van de Ven, A.; Compact complex surfaces. Ergeb. Math. Grenz. 3, 4. Springer-Verlag, Berlin, 1984. MR 749574 (86c:32026)

[BCHM06]
Birkar, C.; Cascini, P.; Hacon, C.; McKernan, J.; Existence of minimal models for varieties of log general type, math.AG/0610203 (2006).

[Ca92]
Campana, F.; Connexité rationelle des variétés de Fano. Ann. Sci. École Norm. Sup. 25 (1992), 539-545. MR 1191735 (93k:14050)

[dJS03]
de Jong, A. J.; Starr, J.; Every rationally connected variety over the function field of a curve has a rational point. Amer. J. Math. 125 (2003), no. 3, 567-580. MR 1981034 (2004h:14018)

[Es03]
Esnault, H.; Varieties over a finite field with trivial Chow group of 0-cycles have a rational point. Invent. Math. 151 (2003), no. 1, 187-191. MR 1943746 (2004e:14015)

[EX07]
Esnault, H.; Xu, C.; Congruence for rational points over finite fields and coniveau over local fields, math.NT/0706.0972 (2007). To appear in Trans. Amer. Math. Soc.

[FR05]
Fakhruddin, N.; Rajan, C.S.; Congruences for rational points on varieties over finite fields. Math. Ann. 333 (2005), no. 4, 797-809. MR 2195144 (2006h:14028)

[GHS03]
Graber, T.; Harris, J.; Starr, J.; Families of rationally connected varieties. J. Amer. Math. Soc. 16 (2003), no. 1, 57-67. MR 1937199 (2003m:14081)

[GHMS05]
Graber, T.; Harris, J.; Mazur, B.; Starr, J.; Rational connectivity and sections of families over curves. Ann. Sci. École Norm. Sup. (4) 38 (2005), no. 5, 671-692. MR 2195256 (2006j:14044)

[HM06]
Hacon, C.; McKernan, J.; Boundedness of pluricanonical maps of varieties of general type. Invent. Math. 166 (2006) no. 1, 1-25. MR 2242631 (2007e:14022)

[HM07]
Hacon, C.; McKernan, J.; Shokurov's rational connectedness conjecture. Duke Math. J. 138 (2007) no. 1, 119-136. MR 2309156

[Kol96]
Kollár, J.; Rational curves on algebraic varieties. Ergeb. Math. Grenz. 3. Folge, 32. Springer-Verlag, Berlin, 1996. MR 1440180 (98c:14001)

[Kol05a]
Kollár, J.; A conjecture of Ax and degenerations of Fano varieties, math.AG/0512375 (2005).

[Kol05b]
Kollár, J.; Kodaira's canonical bundle formula and subadjunction, Ch. $ 8$ in Flips for $ 3$-folds and $ 4$-folds, editor A. Corti, Oxford Lecture Series in Mathematics and its applications 35, Oxford University Press, 2007. MR 2352762

[Kol06]
Kollár, J.; Is there a topological Bogomolov-Miyaoka-Yau inequality? math.AG/0602562 (2006).

[KM98]
Kollár, J.; Mori, S.; Birational geometry of algebraic varieties. Cambridge Tracts in Math. 134, Cambridge University Press, Cambridge, 1998. MR 1658959 (2000b:14018)

[KMM92a]
Kollár, J.; Miyaoka, Y.; Mori, S.; Rational connectedness and boundness of Fano manifolds. J. Diff. Geom. 36 (1992), no. 3, 765-779. MR 1189503 (94g:14021)

[KMM92b]
Kollár, J.; Miyaoka, Y.; Mori, S.; Rationally connected varieties. J. Algebraic Geom. 1 (1992), no. 3, 429-448. MR 1158625 (93i:14014)

[MP06]
Mori, M.; Prokhorov, Y.; On $ \mathbb{Q}$-conic bundles, math.AG/0603736 (2006). To appear in Publ. Res. Inst. Math. Sci.

[Re]
Reid, M.; Young person's guide to canonical singularities. Algebraic geometry, Bowdoin, 1985 (Brunswick, Maine, 1985), 345-414, Proc. Sympos. Pure Math., 46, Part 1, Amer. Math. Soc., Providence, RI, 1987. MR 927963 (89b:14016)

[St06]
Starr, J.; Degenerations of rationally connected varieties and PAC fields, math.AG/0602649, (2006).

[Zh06]
Zhang, Q.; Rational connectedness of log $ \mathbb{Q}$-Fano varieties. J. Reine Angew. Math. 590 (2006), 131-142. MR 2208131 (2006m:14021)


Similar Articles:

Retrieve articles in Transactions of the American Mathematical Society with MSC (2000): 14J26, 14J45, 14E30, 14G27

Retrieve articles in all Journals with MSC (2000): 14J26, 14J45, 14E30, 14G27


Additional Information:

Amit Hogadi
Affiliation: Department of Mathematics, Princeton University, Princeton, New Jersey 08544
Address at time of publication: School of Mathematics, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005 India
Email: amit@math.princeton.edu

Chenyang Xu
Affiliation: Department of Mathematics, Princeton University, Princeton, New Jersey 08544
Email: chenyang@math.princeton.edu

DOI: 10.1090/S0002-9947-09-04715-1
PII: S 0002-9947(09)04715-1
Received by editor(s): June 6, 2007
Received by editor(s) in revised form: November 29, 2007
Posted: March 3, 2009
Copyright of article: Copyright 2009, American Mathematical Society
The copyright for this article reverts to public domain after 28 years from publication.




AMS and Social Media LinkedIn Facebook Podcasts Twitter YouTube RSS Feeds Blogs Wikipedia