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diverietti
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Here is how it works for the (complex) Grassmannian. I will leave you the pleasure to extend this point of view to others homogeneous spaces (for instance complete and incomplete flag manifolds).

Firs of all, let me give a slightly different point of view for the Euler exact sequence on the projective space. Let $V$ be a complex vector space of dimension $n+1$ and $P(V)$ its corresponding projective space of lines. Call $\underline V=P(V)\times V$ the trivial rank $n+1$ vector bundle with fiber $V$ on $P(V)$. Then you have the short exact sequence \begin{equation} 0\to\mathcal O(-1)\to\underline V\to H\to 0, \end{equation} where $\mathcal O(-1)$ is the tautological line bundle on $P(V)$ and $H$ is the quotient rank $n$ vector bundle $\underline V/\mathcal O(-1)$.

Now, looking at the differential $d\pi_x\colon V\to T_{P(V),[x]}$ of the projection $\pi\colon V\setminus\{0\}\to P(V)$, it is straightforward to see that it defines a canonical isomorphism $$ T_{P(V)}\simeq H\otimes\mathcal O(1). $$ Tensoring the short exact sequence above by $\mathcal O(1)$ and using this canonical isomorphism you get the Euler exact sequence $$ 0\to \mathcal O\to\underline V\otimes\mathcal O(1)\to T_{P(V)}\to 0 $$ (to get your version just notice that $\underline V\otimes\mathcal O(1)\simeq\mathcal O(1)^{\oplus(n+1)}$, then take the dual exact sequence).

Now, let $V$ be of dimension $d$ and $G_r(V)$ be the Grassmannian of $r$-codimensional vector subspaces of $V$. Consider the tautological subbundle $S\subset \underline V=G_r(V)\times V$ and the associated short exact sequence $$ 0\to S\to\underline V\to Q\to 0, $$ where $Q=\underline V/S$. Similarly as before, it is straightforwardly seen that there is a canonical isomorphism $$ T_{G_r(V)}\simeq S^*\otimes Q\simeq\operatorname{Hom}(S,Q). $$ Tensoring by $S^*$, you get your Euler sequence for the Grassmannian, that is $$ 0\to S^*\otimes S\to\underline V\otimes S^*\to T_{G_r(V)}\to 0. $$ Of course, it reduces to the standard one whenever $r=d-1$, and playing with the short exact sequence you can give it your favorite shape (taking duals, tensoring with other vector bundles...).

Observe finally that $$ \det S^*\simeq\det Q $$ is the (very) ample line bundle on $G_r(V)$ which gives the Plücker embedding into projective space and whose first Chern class generates $H^2(G_r(V),\mathbb Z)$.

Here is how it works for the (complex) Grassmannian. I will leave you the pleasure to extend this point of view to others homogeneous spaces (for instance complete and incomplete flag manifolds).

Firs of all, let me give a slightly different point of view for the Euler exact sequence on the projective space. Let $V$ be a complex vector space of dimension $n+1$ and $P(V)$ its corresponding projective space of lines. Call $\underline V=P(V)\times V$ the trivial rank $n+1$ vector bundle with fiber $V$ on $P(V)$. Then you have the short exact sequence \begin{equation} 0\to\mathcal O(-1)\to\underline V\to H\to 0, \end{equation} where $\mathcal O(-1)$ is the tautological line bundle on $P(V)$ and $H$ is the quotient rank $n$ vector bundle $\underline V/\mathcal O(-1)$.

Now, looking at the differential $d\pi_x\colon V\to T_{P(V),[x]}$ of the projection $\pi\colon V\setminus\{0\}\to P(V)$, it is straightforward to see that it defines a canonical isomorphism $$ T_{P(V)}\simeq H\otimes\mathcal O(1). $$ Tensoring the short exact sequence above by $\mathcal O(1)$ and using this canonical isomorphism you get the Euler exact sequence $$ 0\to \mathcal O\to\underline V\otimes\mathcal O(1)\to T_{P(V)}\to 0 $$ (to get your version just notice that $\underline V\otimes\mathcal O(1)\simeq\mathcal O(1)^{\oplus(n+1)}$, then take the dual exact sequence).

Now, let $V$ be of dimension $d$ and $G_r(V)$ be the Grassmannian of $r$-codimensional vector subspaces of $V$. Consider the tautological subbundle $S\subset \underline V=G_r(V)\times V$ and the associated short exact sequence $$ 0\to S\to\underline V\to Q\to 0, $$ where $Q=\underline V/S$. Similarly as before, it is straightforwardly seen that there is a canonical isomorphism $$ T_{G_r(V)}\simeq S^*\otimes Q\simeq\operatorname{Hom}(S,Q). $$ Tensoring by $S^*$, you get your Euler sequence for the Grassmannian, that is $$ 0\to S^*\otimes S\to\underline V\otimes S^*\to T_{G_r(V)}\to 0. $$ Of course, it reduces to the standard one whenever $r=d-1$, and playing with the short exact sequence you can give it your favorite shape (taking duals, tensoring with other vector bundles...).

Here is how it works for the (complex) Grassmannian. I will leave you the pleasure to extend this point of view to others homogeneous spaces (for instance complete and incomplete flag manifolds).

Firs of all, let me give a slightly different point of view for the Euler exact sequence on the projective space. Let $V$ be a complex vector space of dimension $n+1$ and $P(V)$ its corresponding projective space of lines. Call $\underline V=P(V)\times V$ the trivial rank $n+1$ vector bundle with fiber $V$ on $P(V)$. Then you have the short exact sequence \begin{equation} 0\to\mathcal O(-1)\to\underline V\to H\to 0, \end{equation} where $\mathcal O(-1)$ is the tautological line bundle on $P(V)$ and $H$ is the quotient rank $n$ vector bundle $\underline V/\mathcal O(-1)$.

Now, looking at the differential $d\pi_x\colon V\to T_{P(V),[x]}$ of the projection $\pi\colon V\setminus\{0\}\to P(V)$, it is straightforward to see that it defines a canonical isomorphism $$ T_{P(V)}\simeq H\otimes\mathcal O(1). $$ Tensoring the short exact sequence above by $\mathcal O(1)$ and using this canonical isomorphism you get the Euler exact sequence $$ 0\to \mathcal O\to\underline V\otimes\mathcal O(1)\to T_{P(V)}\to 0 $$ (to get your version just notice that $\underline V\otimes\mathcal O(1)\simeq\mathcal O(1)^{\oplus(n+1)}$, then take the dual exact sequence).

Now, let $V$ be of dimension $d$ and $G_r(V)$ be the Grassmannian of $r$-codimensional vector subspaces of $V$. Consider the tautological subbundle $S\subset \underline V=G_r(V)\times V$ and the associated short exact sequence $$ 0\to S\to\underline V\to Q\to 0, $$ where $Q=\underline V/S$. Similarly as before, it is straightforwardly seen that there is a canonical isomorphism $$ T_{G_r(V)}\simeq S^*\otimes Q\simeq\operatorname{Hom}(S,Q). $$ Tensoring by $S^*$, you get your Euler sequence for the Grassmannian, that is $$ 0\to S^*\otimes S\to\underline V\otimes S^*\to T_{G_r(V)}\to 0. $$ Of course, it reduces to the standard one whenever $r=d-1$, and playing with the short exact sequence you can give it your favorite shape (taking duals, tensoring with other vector bundles...).

Observe finally that $$ \det S^*\simeq\det Q $$ is the (very) ample line bundle on $G_r(V)$ which gives the Plücker embedding into projective space and whose first Chern class generates $H^2(G_r(V),\mathbb Z)$.

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diverietti
  • 7.9k
  • 34
  • 61

Here is how it works for the (complex) Grassmannian. For the moment I will leave you the pleasure to extend this point of view to others homogeneous spaces (for instance complete and incomplete flag manifolds).

Firs of all, let me give a slightly different point of view for the Euler exact sequence on the projective space. Let $V$ be a complex vector space of dimension $n+1$ and $P(V)$ its corresponding projective space of lines. Call $\underline V=P(V)\times V$ the trivial rank $n+1$ vector bundle with fiber $V$ on $P(V)$. Then you have the short exact sequence \begin{equation} 0\to\mathcal O(-1)\to\underline V\to H\to 0, \end{equation} where $\mathcal O(-1)$ is the tautological line bundle on $P(V)$ and $H$ is the quotient rank $n$ vector bundle $\underline V/\mathcal O(-1)$.

Now, looking at the differential $d\pi_x\colon V\to T_{P(V),[x]}$ of the projection $\pi\colon V\setminus\{0\}\to P(V)$, it is straightforward to see that it defines a canonical isomorphism $$ T_{P(V)}\simeq H\otimes\mathcal O(1). $$ Tensoring the short exact sequence above by $\mathcal O(1)$ and using this canonical isomorphism you get the Euler exact sequence $$ 0\to \mathcal O\to\underline V\otimes\mathcal O(1)\to T_{P(V)}\to 0 $$ (to get your version just notice that $\underline V\otimes\mathcal O(1)\simeq\mathcal O(1)^{\oplus(n+1)}$, then take the dual exact sequence).

Now, let $V$ be of dimension $d$ and $G_r(V)$ be the Grassmannian of $r$-codimensional vector subspaces of $V$. Consider the tautological subbundle $S\subset \underline V=G_r(V)\times V$ and the associated short exact sequence $$ 0\to S\to\underline V\to Q\to 0, $$ where $Q=\underline V/S$. Similarly as before, it is straightforwardly seen that there is a canonical isomorphism $$ T_{G_r(V)}\simeq S^*\otimes Q\simeq\operatorname{Hom}(S,Q). $$ Tensoring by $S^*$, you get your Euler sequence for the Grassmannian, that is $$ 0\to S^*\otimes S\to\underline V\otimes S^*\to T_{G_r(V)}\to 0. $$ Of course, it reduces to the standard one whenever $r=d-1$, and playing with the short exact sequence you can give it your favorite shape (taking duals, tensoring with other vector bundles...).

Here is how it works for the (complex) Grassmannian. For the moment I will leave you the pleasure to extend this point of view to others homogeneous spaces (for instance complete and incomplete flag manifolds).

Firs of all, let me give a slightly different point of view for the Euler exact sequence on the projective space. Let $V$ be a complex vector space of dimension $n+1$ and $P(V)$ its corresponding projective space of lines. Call $\underline V=P(V)\times V$ the trivial rank $n+1$ vector bundle with fiber $V$ on $P(V)$. Then you have the short exact sequence \begin{equation} 0\to\mathcal O(-1)\to\underline V\to H\to 0, \end{equation} where $\mathcal O(-1)$ is the tautological line bundle on $P(V)$ and $H$ is the quotient rank $n$ vector bundle $\underline V/\mathcal O(-1)$.

Now, looking at the differential $d\pi_x\colon V\to T_{P(V),[x]}$ of the projection $\pi\colon V\setminus\{0\}\to P(V)$, it is straightforward to see that it defines a canonical isomorphism $$ T_{P(V)}\simeq H\otimes\mathcal O(1). $$ Tensoring the short exact sequence above by $\mathcal O(1)$ and using this canonical isomorphism you get the Euler exact sequence $$ 0\to \mathcal O\to\underline V\otimes\mathcal O(1)\to T_{P(V)}\to 0 $$ (to get your version just notice that $\underline V\otimes\mathcal O(1)\simeq\mathcal O(1)^{\oplus(n+1)}$, then take the dual exact sequence).

Now, let $V$ be of dimension $d$ and $G_r(V)$ be the Grassmannian of $r$-codimensional vector subspaces of $V$. Consider the tautological subbundle $S\subset \underline V=G_r(V)\times V$ and the associated short exact sequence $$ 0\to S\to\underline V\to Q\to 0, $$ where $Q=\underline V/S$. Similarly as before, it is straightforwardly seen that there is a canonical isomorphism $$ T_{G_r(V)}\simeq S^*\otimes Q\simeq\operatorname{Hom}(S,Q). $$ Tensoring by $S^*$, you get your Euler sequence for the Grassmannian, that is $$ 0\to S^*\otimes S\to\underline V\otimes S^*\to T_{G_r(V)}\to 0. $$ Of course, it reduces to the standard one whenever $r=d-1$, and playing with the short exact sequence you can give it your favorite shape (taking duals, tensoring with other vector bundles...).

Here is how it works for the (complex) Grassmannian. I will leave you the pleasure to extend this point of view to others homogeneous spaces (for instance complete and incomplete flag manifolds).

Firs of all, let me give a slightly different point of view for the Euler exact sequence on the projective space. Let $V$ be a complex vector space of dimension $n+1$ and $P(V)$ its corresponding projective space of lines. Call $\underline V=P(V)\times V$ the trivial rank $n+1$ vector bundle with fiber $V$ on $P(V)$. Then you have the short exact sequence \begin{equation} 0\to\mathcal O(-1)\to\underline V\to H\to 0, \end{equation} where $\mathcal O(-1)$ is the tautological line bundle on $P(V)$ and $H$ is the quotient rank $n$ vector bundle $\underline V/\mathcal O(-1)$.

Now, looking at the differential $d\pi_x\colon V\to T_{P(V),[x]}$ of the projection $\pi\colon V\setminus\{0\}\to P(V)$, it is straightforward to see that it defines a canonical isomorphism $$ T_{P(V)}\simeq H\otimes\mathcal O(1). $$ Tensoring the short exact sequence above by $\mathcal O(1)$ and using this canonical isomorphism you get the Euler exact sequence $$ 0\to \mathcal O\to\underline V\otimes\mathcal O(1)\to T_{P(V)}\to 0 $$ (to get your version just notice that $\underline V\otimes\mathcal O(1)\simeq\mathcal O(1)^{\oplus(n+1)}$, then take the dual exact sequence).

Now, let $V$ be of dimension $d$ and $G_r(V)$ be the Grassmannian of $r$-codimensional vector subspaces of $V$. Consider the tautological subbundle $S\subset \underline V=G_r(V)\times V$ and the associated short exact sequence $$ 0\to S\to\underline V\to Q\to 0, $$ where $Q=\underline V/S$. Similarly as before, it is straightforwardly seen that there is a canonical isomorphism $$ T_{G_r(V)}\simeq S^*\otimes Q\simeq\operatorname{Hom}(S,Q). $$ Tensoring by $S^*$, you get your Euler sequence for the Grassmannian, that is $$ 0\to S^*\otimes S\to\underline V\otimes S^*\to T_{G_r(V)}\to 0. $$ Of course, it reduces to the standard one whenever $r=d-1$, and playing with the short exact sequence you can give it your favorite shape (taking duals, tensoring with other vector bundles...).

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diverietti
  • 7.9k
  • 34
  • 61

Here is how it works for the (complex) Grassmannian. For the moment I will leave you the pleasure to extend this point of view to others homogeneous spaces (for instance complete and incomplete flag manifolds).

Firs of all, let me give a slightly different point of view for the Euler exact sequence on the projective space. Let $V$ be a complex vector space of dimension $n+1$ and $P(V)$ its corresponding projective space of lines. Call $\underline V=P(V)\times V$ the trivial rank $n+1$ vector bundle with fiber $V$ on $P(V)$. Then you have the short exact sequence \begin{equation} 0\to\mathcal O(-1)\to\underline V\to H\to 0, \end{equation} where $\mathcal O(-1)$ is the tautological line bundle on $P(V)$ and $H$ is the quotient rank $n$ vector bundle $\underline V/\mathcal O(-1)$.

Now, looking at the differential $d\pi_x\colon V\to T_{P(V),[x]}$ of the projection $\pi\colon V\setminus\{0\}\to P(V)$, it is straightforward to see that it defines a canonical isomorphism $$ T_{P(V)}\simeq H\otimes\mathcal O(1). $$ Tensoring the short exact sequence above by $\mathcal O(1)$ and using this canonical isomorphism you get the Euler exact sequence $$ 0\to \mathcal O\to\underline V\otimes\mathcal O(1)\to T_{P(V)}\to 0 $$ (to get your version just notice that $\underline V\otimes\mathcal O(1)\simeq\mathcal O(1)^{\oplus(n+1)}$, then take the dual exact sequence).

Now, let $V$ be of dimension $d$ and $G_r(V)$ be the Grassmannian of $r$-codimensional vector subspaces of $V$. Consider the tautological subbundle $S\subset \underline V=G_r(V)\times V$ and the associated short exact sequence $$ 0\to S\to\underline V\to Q\to 0, $$ where $Q=\underline V/S$. Similarly as before, it is straightforwardly seen that there is a canonical isomorphism $$ T_{G_r(V)}\simeq S^*\otimes Q\simeq\operatorname{Hom}(S,Q). $$ Tensoring by $S^*$, you get your Euler sequence for the Grassmannian, that is $$ 0\to S^*\otimes S\to\underline V\otimes S^*\to T_{G_r(V)}\to 0. $$ Of course, it reduces to the standard one whenever $r=d-1$, and playing with the short exact sequence you can give it your favorite shape (taking duals, tensoring with other vector bundles...).