Simplification - complicated summation involving delta functions

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The discussion centers on simplifying a summation involving delta functions, specifically the expression \(\frac{1}{\sqrt{(2^3)}}\sum[δ(k+1)+δ(k-1)]|k>\) for \(k=0\) to \(7\). Participants question whether the first delta function can be ignored since \(k\) is not defined for \(-1\) and express confusion about the notation used for delta functions, debating whether they represent Kronecker or Dirac deltas. There is a consensus that the problem statement lacks clarity and that the poster should provide more accurate details and their thought process for better assistance. The discussion highlights the importance of precise notation and definitions in mathematical problems. Overall, the conversation emphasizes the need for clear problem statements in homework forums.
Halaaku
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Simplification -- complicated summation involving delta functions

Homework Statement



\frac{1}{\sqrt{(2^3)}}\sum[δ(k+1)+δ(k-1)]|k> for k=0 to 7

Homework Equations





The Attempt at a Solution


I am trying to simplify the above expression. I get \frac{1}{∏*\sqrt{(2^3)}} |1>, which is incorrect because |1> should have occurred with a constant 1.
Is it right to say that the first delta function can be ignored because my K is not defined for -1?
 
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Is this really the correct problem statement ? Or just some step in a sequence of steps where you stumble at this point ?

Any idea what the |k> stand for ?

What definition of (or prescription for) ##\delta## do you have available under 2. ?
 
Halaaku, when you post in the homework forum, you need to state the problem more accurately than this, and then show us your thoughts on how to solve it.

If it's a sum rather than an integral, I have to assume that the deltas are Kronecker deltas rather than Dirac deltas. But if you use the notation ##\delta(k-1)## rather than ##\delta_{k,1}##, I have to assume that these are Dirac deltas. The problem doesn't make much sense as it appears in your post.
 

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