\def\nfr{{Laboratoire de Math{\'e}matiques Fondamentales}\bk
        {Universit{\'e} de Pierre et Marie Curie}\bk
        {4 Place Jussieu }\bk
        {Paris 75252 Cedex 05, \ \ France}}
%
%
\def\ninst{{Department of Theoretical Mathematics}  \bk
          {The Weizmann Institute of Science}\bk
         {Rehovot 76100, \ \ Israel}}
%

%
\def\fr{\ctr{Laboratoire de Math{\'e}matiques Fondamentales}
        \ctr{Universit{\'e} de Pierre et Marie Curie}
        \ctr{4 Place Jussieu }
        \ctr{Paris 75252 Cedex 05, \ \ France}}
%
\def\ctrl{\centerline}
%
\def\prof{\ctr{The Donald Frey Professorial Chair}
           \ctr{Department of Theoretical Mathematics}
           \ctr{The Weizmann Institute of Science}
           \ctr{Rehovot 76100, \ \ Israel }}
%
%
%
\def\inst{\ctr{Department of Theoretical Mathematics}
          \ctr{The Weizmann Institute of Science}
          \ctr{Rehovot 76100, \ \ Israel}}
%
%


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\cleaders\hbox{$\mkern-2mu \mathord= \mkern-2mu$}\hfill
\mkern-6mu \mathord\Rightarrow$}
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\def\Leftarrowfill{$\mathsurround=0pt
\mathord\Leftarrow\mkern-6mu
\cleaders\hbox{$\mkern-3mu\mathord= \mkern-3mu$}\hfill$}
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\def\raf{\hbox to 30pt{\Rightarrowfill}}
\def\laf{\hbox to 30pt{\Leftarrowfill}}
\def\rafl{\laf\hskip  -1pt\raf}

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\def\exla{\hbox to 40pt{\leftarrowfill}}
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\def\rmap{\la\hskip -4pt\ln}
\def\rrmap{\lla\hskip -4.2pt\ln}
%
%
\def\lmps{\longmapsto}
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\font\bigsimeq=cmsy10 scaled\magstep 5
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%                 \def\circ{\hbox{\cash\char '015}}
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%
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\def\agll{>\hskip-3pt -}
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\def\3{\vbox{\vskip 3truecm}}
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\def\tf{\vbox{\vskip 2.5truecm}}
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\def\5{\vbox{\vskip 5truecm}}
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\def\gen{general}
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\def\style{\scriptstyle}

\def\iff{if and only if}
%
\def\lw{lowest weight}
\def\hw{highest weight}
%
\def\rsp{respectively}
%
\def\class{classification}
%
\def\anti{antiautomorphism}
\def\auto{automorphism}
%
\def\cl{class}
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\def\loss{loss of generality}
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\def\wloss{without loss of generality}
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%
\def\hy{hypothesis}
\def\hey{hypotheses}

\def\hp{hypersurface}
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\def\smd{submodule}
%
\def\corr{correspond}
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\def\dff{different}
%
\def\bsa{{\buildrel\sim\over\lra}}
%
\def\bal{{\buildrel\sim\over\lla}}
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\def\irr{irreducible}
%
\def\sa{subalgebra}
%
\def\Ip{In particular}
\def\ip{in particular}
%
\def\stf{straightforward}
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\def\po{polynomial}
%
\def\hog{homogeneous}
%
\def\hom{homomorphism}
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\def\fu{fundamental}
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\def\coe{coefficient}
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\def\com{computation}
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\def\ds{\diamondsuit}
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\def\half{{1\over 2}}
%
\def\qt{{1\over 4}}
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\def\ch{character}
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\def\mt{multipl}
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\def\dec{decomposition}
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\def\rep{represent}
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\def\rept{representation theory}
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\def\q{quantization}
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\def\ev{enveloping algebra}
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\def\qg{quantum group}
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\def\li{Lie algebra}
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\def\nil{nilpotent}
\def\nilo{nilpotent orbit}
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\def\sin{singular}
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\def\iso{isomorph}
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\def\di{dimension}
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\def\ann{annihilator}
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\def\ed{endomorph}
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\def\ss{semisimple}
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\def\itp{interpretation}
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\def\spl{special}
%
\def\ind{independent}
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\def\inc{independence}
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\def\ma{mathematic}
%
\def\DTM{Department of Theoretical Mathematics}
\def\dtm{department of theoretical mathematics}
%
\def\DM{Department of Mathematics}
\def\dm{department of mathematics}
%
\def\FM{Faculty of Mathematics}
\def\FMS{Faculty of Mathematical Sciences}
%
\def\fm{faculty of mathematics}
\def\fms{faculty of mathematical sciences}
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\def\Hf{Hopf algebra}
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\def\hyc{hypercuspidal}
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\def\oh{on the other hand}
%
\def\Oh{On the other hand}
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\def\rhs{on the right hand side}
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\def\lhs{on the left hand side}
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\def\ov{\overline}
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\def\ske{\vskip0.5cm}
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\def\ska{\vskip 1truecm}
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\def\parno{\par\noindent}
%
%
\def\mm
{\vtop{\offinterlineskip\hbox{$\cra$}%
\hbox{\hskip-3pt$\scriptstyle n\rightarrow\mu$}}}
%
%
\def\ml
{\vtop{\offinterlineskip\hbox{$\lra$}%
\hbox{\hskip-3pt$\scriptstyle n\rightarrow\mu$}}}
%


%
\def\dbov#1{\overline{\overline{#1}}}
%
\def\hra{\hookrightarrow}
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\def\hla{\hookleftarrow}
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\def\dbund#1{\underline{\underline{#1}}}
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\def\un{\underline}
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\def\pr{^{\prime}}
%
\def\o{\omega}
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\def\O{\Omega}
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\def\t{\tau}
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\def\v{\vert}
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\def\V{\Vert}
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\def\sm{\setminus}
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\def\esp{\varepsilon}
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\def\ra{\rightarrow}
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\def\la{\leftarrow}
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\def\llra{\longleftrightarrow}
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\def\lra{\longrightarrow}
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\def\Lra{\Longrightarrow}
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\def\a{\alpha}
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\def\dpr{^{\prime\prime}}
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\def\seq{\subseteq}
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\def\sp{\supset}
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\def\g{\gamma}
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\def\G{\Gamma}
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\def\L{\Lambda}
%
\def\nty{\infty}
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\def\fa{\forall}
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\def\p{\partial}
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\def\var{\varphi}
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\def\l{\lambda}
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\def\s{\sigma}
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\def\d{\delta}
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\def\D{\Delta}
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\def\th{\theta}
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\def\Th{\Theta}
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\def\sep{\supseteq}
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\def\n{\nabla}
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\def\dpdots{\cdot^{\cdot^\cdot}}
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\def\emt{\emptyset}
%
\def\limi{\mathop{\it lim}}
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%
\def\ap{\vrule height 12pt depth 4pt}
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\def\Ap{\vrule\vrule  height 12pt depth 4pt}
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%%%%%                   \def\aaline{A\hskip -7pt A}
%%%%%%   \def\bline{\hbox{I\hskip -1pt B}}
%%%%     \def\cline{\hbox{I\hskip-5pt C}}

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%
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\font\mas=msbm10
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%
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%   \def\lline{\hbox{I\hskip -1pt L}}
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\font\mas=msbm10
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\font\mas=msbm10
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\font\mas=msbm10
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% \def\qline{\hbox{I\hskip-5pt Q}}

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\font\mas=msbm10
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% \def\rline{\hbox{I\hskip -1pt R}}
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%
\font\mas=msbm10
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%   \def\tline{\hbox{T\hskip -5pt T}}
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\font\mas=msbm10
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%   \def\hline{\hbox{I\hskip -1.5pt H}}
%
\font\mas=msbm10
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%   \def\xline{\hbox{I\hskip -1pt X}}
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\font\mas=msbm10
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%
%
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\def\ssq{\hbox{\sym\char'121}}
\def\ssr{\hbox{\sym\char'122}}
\def\ssz{\hbox{\sym\char'132}}


%   \def\zline{\hbox{Z\hskip -4pt Z}}
%
%   \def\qlin {\hbox{$\;$ \cc\hskip-4pt Q$\!$ }}
%   \def\qlin {\hbox{$\;$ \cc\hskip-4pt Q$\!$ }}



%     \newbox\cbox\setbox\cbox\hbox{Q}
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%       \def\qline{\hbox{$\;$ \cc\hskip-4pt Q$\!$ }}






\def\ctr{\centerline}
%
%%%%%  \newbox\cbox\setbox\cbox\hbox{Q}
%%%%%   \def\cc{\vrule height 1\ht\cbox width .6pt}
%%%%%  \def\sline{\hbox{$\;$ \cc\hskip-4pt S$\!$ }}
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%    \def\ppline{\hbox{\sixrm {I\hskip -1.5pt P}}}
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\def\nd{\hbox{/ \hskip-9pt D}}

%
\def\cupdot{\hbox{$\bigcup$\hskip -6pt$\cdot$}}
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%
%
\def\QED{\hbox{\vrule height 5pt \vbox to 5pt{\hrule width 5pt\vfill
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%
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%
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   \vbox{\hrule width 1\wd\plbox}
   \hbox{\vrule height .61\wd\plbox%
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   \vbox{\hrule width 1\wd\plbox}}\>}
%


%
%
\def\black{\penalty 10000\quad\penalty 10000
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%
\def\nv#1{{\accent20 #1}} \let\^^_=\nv
%
%


%
\newbox\onebox
\newbox\hdym\setbox\hdym\hbox{\rm rad\ lim}
\def\radlim#1{
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  \hbox to 1.5\wd\hdym{\hfill \rm rad\ lim\hfill}
  \hbox to 1.5\wd\hdym{\hfill$\scriptstyle #1$\hfill}}
  \copy\onebox}
%
%
\newbox\onebox
\newbox\hdym\setbox\hdym\hbox{\rm Sup}
\def\Sup#1{
  \setbox\onebox\vtop{\baselineskip 7pt
  \hbox to 1.5\wd\hdym{\hfill \rm Sup \hfill}
  \hbox to 1.5\wd\hdym{\hfill$\scriptstyle #1$\hfill}}
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%
%    \def\aline{\raise 1.6pt \hbox{{\sevenrm / }}\hskip -6.0pt {\rm A}}
%
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%
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   \hbox{\vrule height .61\wd\minbox%
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%
\def\sqplus{\>\vbox{\lineskip=0pt \offinterlineskip
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%
%
%
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\def\OO{\hbox to 35pt{0\hl 0}}
\def\OOO{\hbox to 60pt{0\hl 0\hl 0}}
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%
%
%
%
\def\arule{\ \vrule height 12pt depth 6pt\ }
%
%
\newbox\onebox
\newbox\arrow\setbox\arrow\hbox{$\longrightarrow$}
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%
%
%
%
\def\luv{\vtop{\offinterlineskip\hbox{$\longrightarrow$}%
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%
\def\brule{\vrule height 20pt depth 10pt}
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%
\def\smsq{\hbox{\vrule height 3pt \vbox to 3pt{\hrule width 3pt\vfill
\hrule width 3pt}\vrule height 3pt}}
%
%
\def\triple{\raise 1pt\hbox{\spose {$\scriptscriptstyle \app$}}
\raise 5pt\hbox{\spose {$\scriptscriptstyle \le $}}
\lower 2pt\hbox{$\scriptscriptstyle =$}}
%
%
\def\circle#1{{\accent23 #1}}
%
%
\def\filcirc#1{\rlap{\hbox to 10pt {\hfill$\bigcirc$\hfill}}
\hbox to 10pt
{\hfill\eightb #1\hfill}}
%
%
\overfullrule=0pt
\def\filbcirc#1{\llap{\hbox to 27pt {\hfill\twelvepoint
$\bigcirc$\hfill}}\hbox to 20pt
{\hfill\tenb #1\hfill}}
%
%
%
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%
%