Is this complex vector orthogonal to itself?

In summary, the basis vector (i,0,1) in the space V=Span((i,0,1)) with a standard inner product over C^3 is not orthogonal to itself. This is because the inner product in a complex vector space must be anti-linear in one of the arguments. Therefore, the inner product of this vector with itself is equal to zero.
  • #1
Steve Turchin
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Is the basis vector ##(i,0,1)## in the space ##V=##Span##((i,0,1))## with a standard inner product,over ##\mathbb{C}^3##
orthogonal to itself?
##<(i,0,1),(i,0,1)> = i \cdot i + 0 \cdot 0 + 1 \cdot 1 = -1 + 1 = 0 ##
The inner product (namely dot product) of this vector with itself is equal to zero.
What is going on here?
 
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  • #2
No, it is not orthogonal to itself. The inner product on a complex vector space must be anti-linear in one of the arguments (which one depends on whether you use physics or maths notation). In other words, the complex inner product is given by
$$
\langle x, y \rangle = \sum_k x_k^* y_k.
$$
 
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Related to Is this complex vector orthogonal to itself?

1. What does it mean for a complex vector to be orthogonal to itself?

Orthogonality refers to the relationship between two vectors where they are perpendicular to each other. When a complex vector is orthogonal to itself, it means that it is perpendicular to all other vectors in its vector space and has a magnitude of zero.

2. How can I determine if a complex vector is orthogonal to itself?

To determine if a complex vector is orthogonal to itself, you can use the dot product. If the dot product of the vector with itself is equal to zero, then it is orthogonal to itself. Another way is to check if the magnitude of the vector is equal to zero.

3. Can a complex vector be orthogonal to itself in a non-zero vector space?

No, a complex vector cannot be orthogonal to itself in a non-zero vector space. In a non-zero vector space, all vectors have a magnitude greater than zero and therefore cannot be perpendicular to themselves.

4. Why is orthogonality important in complex vector spaces?

Orthogonality is important in complex vector spaces because it allows us to define a basis for the space. This means that any vector in the space can be expressed as a linear combination of the basis vectors. It also simplifies calculations and allows for the use of orthogonal projections.

5. Are all complex vectors orthogonal to themselves?

No, not all complex vectors are orthogonal to themselves. Only the zero vector or vectors with a magnitude of zero can be considered orthogonal to themselves. Any non-zero vector will have a non-zero dot product with itself, meaning it is not perpendicular to itself.

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