Cross product for complex vectors

In summary, the definition of the cross product is the same for both real and complex vectors. In both cases, the geometric interpretation involves the norm of the vectors and the sine of the angle between them. This concept is generalized for higher dimensions, but the basic idea remains the same. The cross product also has a length and is perpendicular to the two given vectors in three dimensions, but this is not necessarily true in higher dimensions. The dot product and cross product should not be confused, as they are two distinct operations.
  • #1
dimension10
371
0
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

[tex]||\mathbf{a}\times\mathbf{b}||=||\mathbf{a}|| \; ||\mathbf{b}|| \sin\theta [/tex]

Thanks.
 
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  • #2
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.
 
  • #3
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,

[tex] \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}
\hat{\imath} & \hat{\jmath} & \hat{k} \\
a & b & c \\
P & Q & R
\end{bmatrix}[/tex]
 
  • #4
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.
 
  • #5
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.
 

1. What is a cross product for complex vectors?

A cross product for complex vectors is a mathematical operation that calculates the vector perpendicular to two given vectors in a three-dimensional space. It is commonly used in physics and engineering to determine the direction of a resulting vector in a 3D system.

2. How is the cross product for complex vectors calculated?

The cross product for complex vectors is calculated by taking the determinant of a 3x3 matrix formed by the components of the two given vectors. The resulting vector is perpendicular to both of the original vectors and its magnitude is equal to the area of the parallelogram formed by the two vectors.

3. What is the formula for calculating the cross product for complex vectors?

The formula for calculating the cross product for complex vectors is given by:
A x B = (a2b3 - a3b2)i + (a3b1 - a1b3)j + (a1b2 - a2b1)k
Where A = (a1, a2, a3) and B = (b1, b2, b3) are the two given vectors.

4. How does the cross product for complex vectors differ from the cross product for real vectors?

The cross product for complex vectors differs from the cross product for real vectors in that the resulting vector is a complex number instead of a real number. This is because complex numbers have both a real and imaginary component, while real numbers only have a real component. Additionally, the cross product for complex vectors is only defined in three-dimensional space, whereas the cross product for real vectors can be calculated for any number of dimensions.

5. What are some applications of the cross product for complex vectors?

The cross product for complex vectors has many applications in physics and engineering, such as determining the torque on a rigid body, calculating the magnetic field produced by a current-carrying wire, and finding the direction of the resulting force in a 3D system. It is also used in computer graphics to calculate the normal vector of a surface, which is important for lighting and shading in 3D models.

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