Guys I have this problem:

Is it true that the tautological bundle on $\mathbb{P}^1(\mathbb{C})$ given by $L(-1)=\lbrace (\ell,z)\in\mathbb{P}^1\times \mathbb{C}^2 \: : \: z\in \ell \rbrace $ is a subbundle of $L(0)^2$, where $L(0)\cong \mathbb{P}^1\times \mathbb{C}$ ?

  • $\begingroup$ I mean ... by definition $L(-1) \subset L(0)^2$ right ? $\endgroup$ – user171326 Jan 5 '17 at 22:26
  • $\begingroup$ Can you explain me better? $\endgroup$ – Vincenzo Zaccaro Jan 5 '17 at 22:27
  • 4
    $\begingroup$ I interpret $L(0)^2$ as the trivial bundle over $\mathbb P^1$ with fiber $\mathbb C^2$. So every fiber of $L(-1)$ is a line in $L(0)^2$ so it is a subbundle. $\endgroup$ – user171326 Jan 5 '17 at 22:29
  • $\begingroup$ Ah in this way it's ok! I thought L(0)^2 as cartesian product. $\endgroup$ – Vincenzo Zaccaro Jan 5 '17 at 22:35
  • 4
    $\begingroup$ Yes, for a vector bundle $E^2$ mean $E \oplus E$ where $\oplus$ is the fiberwise direct sum over the same base. $\endgroup$ – user171326 Jan 5 '17 at 22:36

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.