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Symmetric tensor of highest weight modules for $\mathrm{SU}(2)$

The multiplicities of $V_e$ inside $n$-th symmetric power of $V_d$ are given by the Cayley-Sylvester formula $$ P(n,d;\frac{nd-e}{2}) - P(n,d;\frac{nd-e}{2}-1) $$ where $P(n,d;k)$ denotes the number ...
Vít Tuček's user avatar
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5 votes

Which algebraic groups are generated by (lifts of) reflections?

Let $M$ be a division algebra of degree 3 (i.e., dimension 9) over $\mathbf{Q}$ that splits over $\mathbf{R}$, and $M_1$ its norm 1 subgroup. So $M_1$ is a $\mathbf{Q}$-anisotropic simple algebraic ...
YCor's user avatar
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2 votes

Quotients of schemes by connected groups

$\DeclareMathOperator\PGL{PGL}\DeclareMathOperator\GL{GL}$It seems that J. Kollár gave some examples in his paper "Non-quasi-projective moduli spaces". In pg. 1080, I think that there is an ...
afh's user avatar
  • 396
7 votes

Question regarding the definition of linearization of line bundles

I think that you should regard the first definition as an imprecise version of the second definition. For example, suppose that $ X $ is a point and so $ L $ is simply a 1-dimensional vector space. ...
Joel Kamnitzer's user avatar

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