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The quantum general linear group again

Let V be an n-dimensional vector space over a field $\arbK$. Given an invertible $q\in\arbK$, let (y ,z) be the tortile Yang-Baxter-operator on V defined in an earlier section. By this example and this also , from an earlier section, there are strict tensor functors

\begin{displaymath}
\map M\from \tilBraid \to {\Mod_\arbK}\quad,
\quad
\map G\from \tilTan \to {\Mod_\arbK}
\end{displaymath}

taking % latex2html id marker 338
$\bigl(+\,, c_\plusplus\,, \thetaplus\bigr)$ to be $\bigl(V\mkern1mu ,y\,,z\bigr)$ (where we are identifying $\tilBraid$ with the subcategory of $\,\tilTan$ whose objects are positively signed sets, with arrows being ribbons which do not bend around).

Applying Tannaka Duality ideas to M and G, we obtain a co-balanced bi-algebra $E_{\!M}^\pprime$ and a co-tortile bi-algebra $\EsubG'$.



Theorem 19.1   There are $\arbK$-bialgebra isomorphisms (see example from an earlier section):

\begin{displaymath}
E_{\!M}^\pprime\;\isom\; \Mat_q(n)\quad,
\quad
\EsubG'\;\isom\; \GL_q(n)\;.
\end{displaymath}

Corollary 19.2  

$M_{\!q}^{\phj}\!(n)$ is a co-balanced bi-algebra and $\GL_q(n)$ is a co-tortile bi-algebra.



The co-braiding given by $\map \gamma \from \GL_q(n) \XO \GL_q(n) \to \arbK$, and co-twist given by $\map \tau \from \GL_q(n) \XO \GL_q(n) \to \arbK$, satisfy the equations

\begin{eqnarray*}
y(\epseps[i,j]) &\; = \; & \sum\limits_{m,r}
\gamma(x_{im}^{...
...;\;\;
&\; = \; & \sum\limits_m\tau(x_{im}^{\phj})\,\veps_m\hfill
\end{eqnarray*}


This means:

\begin{eqnarray*}
&\gamma(x_{im}^{\phj},x_{jr}^{\phj}) &\; = \;
\cases{
\hfil 1...
...tau(x_{\!ij}^{\phj})
&\; = \qquad q^n_{}\,\delta_{ij}^{\phj}\;.
\end{eqnarray*}



next up previous contents index
Up: Quantum_Groups Previous: Adjoining_an_antipode_to_a_bialgebra   Contents   Index
Ross Moore
1998-10-15