Cross product for complex vectors

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SUMMARY

The discussion clarifies that the definition of the cross product remains consistent for complex vectors, particularly in the context of isomorphism between R2 and C. The geometric interpretation of the cross product, expressed as ||\mathbf{a}\times\mathbf{b}||=||\mathbf{a}|| \; ||\mathbf{b}|| \sin\theta, holds true, emphasizing the relationship between vector norms and the angle between them. However, confusion arose regarding the distinction between the cross product and the dot product, with participants confirming that the cross product is indeed perpendicular to the original vectors in three-dimensional space.

PREREQUISITES
  • Understanding of vector operations in R2 and C
  • Familiarity with geometric interpretations of vector products
  • Knowledge of isomorphism between R2 and C
  • Basic concepts of linear algebra, specifically determinants
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  • Explore the properties of vector isomorphism in linear algebra
  • Study the geometric interpretations of the cross product in higher dimensions
  • Learn about the applications of cross products in physics and engineering
  • Investigate the definitions and properties of complex vector spaces
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Mathematicians, physics students, and engineers interested in vector calculus and the applications of cross products in both real and complex vector spaces.

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I was wondering, is the definition of the cross product the same for complex vectors? And if it is, then how is its geometric interpretation, that is

||\mathbf{a}\times\mathbf{b}||=||\mathbf{a}|| \; ||\mathbf{b}|| \sin\theta

Thanks.
 
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R2 and C are isomorphic.
In particular this means that the geometric interpretation is exactly the same in either R2 or C.
For Rn or Cn, the interpretation is generalized, but it's still the same.
It's still about the norm of the vectors and the cosine of the angle between them.
 
I like Serena said:
R2 and C are isomorphic.
In particular this means that the geometric interpretation is exactly the same in either R2 or C.
For Rn or Cn, the interpretation is generalized, but it's still the same.
It's still about the norm of the vectors and the cosine of the angle between them.

I don't get how it is about the cosine of the angle between them. Shouldn't it be sine?

And is calculating the cross product the same as that for complex vectors? That is,

\left(a\hat{ \imath}+b\hat{\jmath}+c\hat{k} \right)\times \left( P\hat{\imath}+Q\hat{\jmath}+R\hat{k} \right)=\det\begin{bmatrix}<br /> \hat{\imath} &amp; \hat{\jmath} &amp; \hat{k} \\ <br /> a &amp; b &amp; c \\ <br /> P &amp; Q &amp; R<br /> \end{bmatrix}
 
I like Serena said:
R2 and C are isomorphic.
In particular this means that the geometric interpretation is exactly the same in either R2 or C.
For Rn or Cn, the interpretation is generalized, but it's still the same.
It's still about the norm of the vectors and the cosine of the angle between them.
Are you not talking about the dot product? The cross product of two vectors in three dimensions not only has a length but is perpendicular to the two given vectors. In more than three dimensions that is not a single direction.
 
My apologies, that was not one of my brighter responses.
I did indeed mix up the dot product with the cross product.

I'm not aware of any definition of the cross product for complex vectors.
 

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