Evaluating contractions of a tensor product

In summary, ##T = \delta \otimes \gamma## where ##\delta## is the ##(1,1)## Kronecker delta tensor and ##\gamma \in T_p^*(M)##. The components of ##T## are ##T^a_{\,\,\,\,\,bc}## and the possible contractions are ##T^a_{\,\,\,\,\,ab} = \delta^a_b\gamma## and ##T^a_{\,\,\,\,\,ba} = \delta^a_b\gamma##.
  • #1
CAF123
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Homework Statement


Consider ##T = \delta \otimes \gamma## where ##\delta## is the ##(1,1)## Kronecker delta tensor and ##\gamma \in T_p^*(M)##. Evaluate all possible contractions of ##T##.

Homework Equations



Tensor product

The Attempt at a Solution



##\gamma## is therefore a ##(0,1)## tensor and the tensor product with ##(1,1)## yields a ##(1,2)## tensor. The components of ##T## are therefore ##T^a_{\,\,\,\,\,bc}## which gives rise to the two possible contractions ##T^a_{\,\,\,\,\,ab}## or ##T^a_{\,\,\,\,\,ba}##. Do I need to include any more detail? Thanks.
 
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  • #2
I would say you also need to evaluate what these contractions actually are in terms of ##\gamma## and ##\delta##.
 

FAQ: Evaluating contractions of a tensor product

1. What is a tensor product?

A tensor product is a mathematical operation that combines two tensors to create a new tensor. It is denoted by the symbol ⊗ and is commonly used in linear algebra and multilinear algebra.

2. Why is it important to evaluate contractions of a tensor product?

Evaluating contractions of a tensor product allows us to simplify and manipulate complex tensor expressions, making it easier to solve equations and understand the underlying structures in physics and engineering problems.

3. How do you evaluate contractions of a tensor product?

To evaluate a contraction of a tensor product, you first need to identify the indices that are repeated in the tensors. Then, you can replace those indices with the appropriate summation notation and simplify the expression using the properties of tensors.

4. What are some common applications of evaluating contractions of a tensor product?

Some common applications of evaluating contractions of a tensor product include solving problems in general relativity, quantum mechanics, and fluid dynamics. It is also used in computer graphics and image processing to manipulate and transform images.

5. Are there any limitations or challenges when evaluating contractions of a tensor product?

Yes, there can be limitations and challenges when evaluating contractions of a tensor product, especially when dealing with high-dimensional tensors or complex expressions. It requires a good understanding of tensor algebra and can be time-consuming for larger tensors.

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