There are three symbols in relativity textbooks that I've never encoutered before and need lots of help with.(adsbygoogle = window.adsbygoogle || []).push({});

1.Einstein summation convetion : Though not really a symbol i still don't quite understand what is meant by it.

2. Upper case lambda with super scripts and subscripts: It seems to be some sort of linear transformation, but I still don't quite understand it.

3. The great demon, the kronecker delta: I really cannot understand what is meant by this.

The reason I have such a hard time with this notation is because I have very little formal education.

However after the symbols are understood, it becomes very lucid.

Can someone please give me a CLEAR and informal description of what this means with examples relating to relativity and tensor analysis?

I'm very sorry.

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# Three symbols i can never understand in relativity tesbooks

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