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Is this complex vector orthogonal to itself?

  1. Feb 11, 2016 #1
    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?
     
  2. jcsd
  3. Feb 11, 2016 #2

    Orodruin

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    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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