Plücker coordinates: Difference between revisions

Sintel (talk | contribs)
note about duality
Sintel (talk | contribs)
spacing nit
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\begin{align}
\begin{align}
\iota: \mathrm{Gr} (k, n)  
\iota: \mathrm{Gr} (k, n)  
& \to \mathbf{P}\left(\Lambda^{k} \mathbb{R}^n \right) \\
& \to \mathbf{P}\left(\Lambda^{k} \, \mathbb{R}^n \right) \\
\operatorname {span} (m_1, \ldots, m_k)  
\operatorname {span} (m_1, \ldots, m_k)  
& \mapsto \left[ m_1 \wedge \ldots \wedge m_k \right] \, .
& \mapsto \left[ m_1 \wedge \ldots \wedge m_k \right] \, .
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</math>
</math>


Here, <math>\Lambda^{k} \mathbb{R}^n</math> is the k-th exterior power (the subspace containing all k-vectors). This construction is independent of the basis we choose.
Here, <math>\Lambda^{k} \, \mathbb{R}^n</math> is the k-th exterior power (the subspace containing all k-vectors). This construction is independent of the basis we choose.
While the original space of temperaments has dimension <math>k(n-k)</math>, the space of Plücker coordinates is typically larger, with dimension <math>\binom{n}{k} - 1</math>.
While the original space of temperaments has dimension <math>k(n-k)</math>, the space of Plücker coordinates is typically larger, with dimension <math>\binom{n}{k} - 1</math>.