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Adding Tensors

  • Thread starter tetris11
  • Start date
  • #1
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Homework Statement



Is this equation valid?

Axy = BzzBxz+ CxyBxyBxy


The Attempt at a Solution



BzzBxz = Bzxz+z (I think)

CxyBxyBxy = Jxy2xy (I think)

so Axy = Bzxz+z + Jxy2xy

My reasoning:
Since the two terms on the RHS do not share the same index structure, they cannot be added, and they do not share the same index structure with the LHS either.

So this equation is not possible, right?
 

Answers and Replies

  • #2
Hurkyl
Staff Emeritus
Science Advisor
Gold Member
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The problem with the equation is the serious grammatical error with the indices.

Assuming they were filled in correctly, it would depend upon what contractions were implicit in the notation. For example, the following is meaningful:
Axy = BzyCxz + Duv Exy Fuv
 
  • #3
23
0
I dont really follow.
How does that contract?

In your example, would Fuv contract to something like Jk
And then would Bz contract to L (no upper indices?)

Would it be valid to say DuvExyFuv would contract to something like Jkab?
 
Last edited:

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