Should tensor sum be used in matrix mechanics?

In summary, the conversation discusses the concept of nonlocal realism and its implications for the Bell operator. It is noted that using the usual matrix sum, the eigenvalues for the result of measurement can be smaller than 1, which contradicts nonlocal realism. However, using the Kronecker sum, this discrepancy disappears. The conversation also mentions the use of matrices to represent spin 1/2 particles and the difficulty in calculating eigenvalues without a computer. The discussion concludes with a question about the idea of a violation of locality leading to an "under locality" value.
  • #1
jk22
729
24
Suppose the Bell operator ##B=|AB(1,2)+AB(1,3)+AB(2,3)|##

With ##AB\in{1,-1}##

Nonlocal realism implies ##B\in{1,3}##

However using usual matrix sum one eigenvalues for the result of measurement can be smaller than 1, implying nonlocal realism cannot explain the quantum result.

However if the Kronecker sum is used this fact disappears.

So what would these eigenvalues mean experimentally ?
 
Physics news on Phys.org
  • #2
Can't answer the question itself, but as a tip: in LaTeX code the set notation with curly brackets ##\left\{1,-1\right\}## is written as "\left\{1,-1\right\}".
 
  • #3
Thanks for the tip. I thought a bit about my OP

I used "realism", which is a big word from philosophy, but technically I think it's a threshold switch that digitalizes or binarizes the results that makes that difference. So nothing deep.
 
  • #4
As summary matrix mechanics were possible in this forbidden band ##]1,-1[## hence sub-local realistic ?
 
  • #5
jk22 said:
using usual matrix sum one eigenvalues for the result of measurement can be smaller than 1

What "matrix sum" and "eigenvalues" are you talking about? The formula you give in the OP only involves numbers, not matrices.
 
  • Like
Likes jk22
  • #6
Good point, it is if the ##AB##s are raised to the rank of covariance operators of two spin 1/2 particles.

I.e. ##A\rightarrow \vec{n}\cdot\vec{\sigma}## ?

But I could calculate the eigenvalue only with a CAS (computers are useful but it looks like acedia)

Why is that as there is a violation of locality there is also an under locality value ?
 
Last edited:

Related to Should tensor sum be used in matrix mechanics?

1. What is tensor sum and how is it used in matrix mechanics?

Tensor sum is a mathematical operation that combines two tensors (multidimensional arrays) to create a new tensor. In matrix mechanics, tensor sum is used to represent the addition of two matrices, where each element in the resulting matrix is the sum of the corresponding elements in the original matrices.

2. What are the advantages of using tensor sum in matrix mechanics?

Using tensor sum in matrix mechanics allows for efficient and concise representation of mathematical operations, as well as simplifying the process of solving complex equations. It also allows for easier manipulation and transformation of matrices, making it a useful tool in various scientific fields.

3. Are there any limitations to using tensor sum in matrix mechanics?

One limitation of using tensor sum in matrix mechanics is that it can only be applied to matrices of the same dimensions. This means that matrices with different sizes cannot be added using tensor sum. Additionally, tensor sum may not always be the most efficient method for solving certain mathematical problems, so it is important to consider alternative approaches.

4. How does tensor sum differ from tensor product in matrix mechanics?

Tensor sum and tensor product are both mathematical operations involving tensors, but they have different results. While tensor sum combines two tensors to create a new tensor, tensor product creates a new tensor by multiplying corresponding elements from the original tensors. In matrix mechanics, tensor product is often used for operations such as matrix multiplication.

5. Can tensor sum be used in all areas of matrix mechanics?

Yes, tensor sum can be used in all areas of matrix mechanics where addition of matrices is required. This includes applications in physics, engineering, and computer science. However, it is important to note that there may be cases where other methods may be more suitable, so it is always important to consider the specific problem at hand when choosing a mathematical approach.

Similar threads

  • Quantum Physics
Replies
1
Views
1K
  • Quantum Physics
Replies
2
Views
1K
Replies
1
Views
1K
  • Quantum Interpretations and Foundations
2
Replies
37
Views
2K
Replies
6
Views
1K
Replies
10
Views
2K
Replies
3
Views
678
Replies
80
Views
4K
Replies
7
Views
1K
  • Quantum Physics
Replies
1
Views
855
Back
Top