Help Solve a Question on Antisymmetrical Tensor Density

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The discussion centers on a question regarding antisymmetrical tensor density, with the original poster seeking clarification after reading Geroch's "Geometrical Quantum Mechanics." They express familiarity with general relativity and tensor calculations but struggle with the specific concept of tensor density, noting limited resources on the topic. Respondents emphasize the importance of understanding the properties of totally antisymmetric matrices and suggest that knowledge of linear algebra, the Levi-Cevita symbol, and metric transformations is crucial for solving the problem. They encourage the poster to clarify their specific difficulties to receive more targeted assistance. Overall, a deeper understanding of the foundational concepts in differential geometry is necessary to tackle the question effectively.
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i have a question on antisymmetrical tensor density which i read on the internet
i read Geroch's "Geometrical Quantum Mechanics" but nothing changed.

here is the picture about this question http://p13.freep.cn/p.aspx?u=v20_p13_photo_1211140612144629_0.jpg

can anybody help me to solve it?
 
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this is not a homework question, it's just a question i read on the internet and cannot find the solution
 
What is your background? Why are you interested? Which part gives you difficulty?

You can't just paste a high level differential geometry question and ask how it's answered. The answer will depend very much on what it is that you want to know. Solution, by itself, will look to you just as cryptic as the question unless you are very, very close to understanding it already.
 
K^2 said:
What is your background? Why are you interested? Which part gives you difficulty?

You can't just paste a high level differential geometry question and ask how it's answered. The answer will depend very much on what it is that you want to know. Solution, by itself, will look to you just as cryptic as the question unless you are very, very close to understanding it already.
i study general relativity by myself and did several exercises sucessifully, but only this i didn't understand. i can calculate tensors and the transformation of tensors, christoffel symbols, metrics etc. i read several books about general relativity, only Pauli's talked about tensor density, then i didnt pay much attention on it. Then i found this exercise which need the knowledge of tensor density that i could find few books talk about it, acctually only Pauli's and one on the internet.
 
You don't need to know anything special. It's all right there, really. You are given that g_{\mu \nu \alpha \beta} is totally antisymmetric. That means that the matrix will change sign if you swap any two indices. For part one you just need to prove that any two matrices with such property are proportional to each other. That's just linear algebra.

The rest of it is pretty straight forward as well, so long as you know a bit about Levi-Cevita symbol, metric transformations, and covariant derivative. If you've worked with Christoffel symbol, you should have come across all that before.
 
So I know that electrons are fundamental, there's no 'material' that makes them up, it's like talking about a colour itself rather than a car or a flower. Now protons and neutrons and quarks and whatever other stuff is there fundamentally, I want someone to kind of teach me these, I have a lot of questions that books might not give the answer in the way I understand. Thanks

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