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Comparison of fundamental group schemes of a projective variety and an ample hypersurface
Author(s):
Indranil
Biswas;
Yogish
I.
Holla
Journal:
J. Algebraic Geom.
16
(2007),
547-597.
Posted:
March 20, 2007
Retrieve article in:
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Abstract |
References |
Additional information
Abstract:
Let  be a smooth projective variety defined over an algebraically closed field, and let  be an ample line bundle over  . We prove that for any smooth hypersurface  on  in the complete linear system  , the inclusion map  induces an isomorphism of fundamental group schemes, provided  is sufficiently large and  . If  , and  is sufficiently large, then the induced homomorphism of fundamental group schemes remains surjective. We give an example to show that the homomorphism of fundamental group schemes induced by the inclusion map of a reduced ample curve in a smooth projective surface is not surjective in general.
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Additional Information:
Indranil
Biswas
Affiliation:
School of Mathematics, Tata Institute of Fundamental Research, Homi Bhabha Road, Bombay 400005, India
Email:
indranil@math.tifr.res.in
Yogish
I.
Holla
Affiliation:
School of Mathematics, Tata Institute of Fundamental Research, Homi Bhabha Road, Bombay 400005, India
Email:
yogi@math.tifr.res.in
PII:
S 1056-3911(07)00449-3
Received by editor(s):
February 16, 2006
Received by editor(s) in revised form:
February 20, 2006
Posted:
March 20, 2007
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