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تسجيل مستخدم جديدTopological rigidity of algebraic $P_3$-bundles over curves
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تأليف
Alexander Schmitt
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A projective algebraic surface which is homeomorphic to a ruled surface over a curve of genus $gge 1$ is itself a ruled surface over a curve of genus $g$. In this note, we prove the analogous result for projective algebraic manifolds of dimension 4 in case $gge 2$.
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If $M$ is a compact 3-manifold whose first betti number is 1, and $N$ is a compact 3-manifold such that $pi_1N$ and $pi_1M$ have the same finite quotients, then $M$ fibres over the circle if and only if $N$ does. We prove that groups of the form $F_2
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