What symbol is used for linear operator actions?

AI Thread Summary
The discussion focuses on the appropriate notation for linear operator actions, specifically for a mapping G: H->H applied to a vector v in R2 to R3. The consensus is that using G(v) is the clearest and most accepted notation, as alternatives like the tensor product or dot product have been deemed inappropriate. Emphasis is placed on the fact that G is a 3x3 matrix operator acting on a 3x1 vector. Additionally, the notation G^n(v) is confirmed as suitable for representing the repeated application of G to v. Overall, clarity and avoiding ambiguity in mathematical notation are prioritized.
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Given a vector v\in H: R2->R3 which is a function from R2 to R3, and an operator G: H->H on the space H in which v lives, what is the most commonly used symbol to refer to this mapping, i.e., G(v)=G\otimes v or something else?
 
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G(v) is fine.
 
Thank you for replying, but I want to emphasize that G is a 3x3 matrix valued operator that multiplies the 3x1 vector valued function v then integrated over the entire domain, is the tensor product \otimes appropriate? I used a dot but was complained about by the reviewer.
 
The tensor product is not appropriate, neither is the dot. Using G(v) makes most sense. Is there a reason why you don't want to use G(v)?
 
Thanks again for clarifying, I guess I just wanted to emphasize the matrix vector multiplication part, I'll use G(v) so that there's no ambiguity. One more question though, if I apply G n times to v, n>=0, is G^n(v) appropriate?
 
I found the notation G^n(v)=G(G(G...G(v)...)) in a textbook. Thank you both!
 
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