Cartesian Tensors and some proofs and problems regarding it.

AI Thread Summary
The discussion centers on proving that the Kronecker delta is an isotropic tensor, which requires demonstrating that it remains unchanged under specific coordinate transformations. The participant expresses difficulty in understanding the necessary transformations and seeks guidance. It is emphasized that a foundational understanding of tensors and the definition of isotropic tensors is crucial for solving the problem. Additionally, knowledge of the general method for transforming tensor components is necessary to apply to the specific transformations in question. Overall, assistance is offered to help clarify these concepts and facilitate the proof.
Raj90
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Homework Statement



I am stuck at this point where I have to prove that the kronecker delta is isotropic tensor.

Homework Equations



δij=δji

The Attempt at a Solution


I know that to prove this I have to show that under coordinate transfor mation it does not change..but it's a bit diff for me to get it right...
 
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Raj90 said:
I have to prove that the kronecker delta is isotropic tensor.


I know that to prove this I have to show that under coordinate transfor mation it does not change.


Hi, Raj90. Welcome to PF.

You don't mean any coordinate transformation, right? What type of coordinate transformation are you assuming in order to show that the tensor is isotropic?

Do you know the general method for transforming tensor components from one system of coordinates to another?
 
Hey TSny!

No I am completely new to the subject..that is why I need some help and guidance as to what I should refer to solve the given problem.
 
You need to have some basic knowledge about tensors to solve the problem. We are here to help you once you have made an attempt and you show us your work so far. I will just say that for this problem you essentially need the following:

1. Know the definition of "isotropic tensor". This will tell you what type of coordinate transformation you need to consider.

2. Know the general method of transforming tensor components and apply this method to the specific type of coordinate transformation you are dealing with in this problem.
 
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