Recent content by guru_4

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    Graduate What Are the Key Concepts in Tensor Calculus?

    You can search summation convention. It means sum all possible combinations of indices. https://rpubs.com/lizhi1800/Riemann_curvature_tensor_2nd_kind
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    Undergrad A couple questions about the Riemann Tensor, definition and convention

    https://rpubs.com/lizhi1800/Riemann_curvature_tensor_2nd_kind Here is a full code treatment of Riemman tensor.
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    Undergrad Christoffel Symbols: Difference, Importance & Uses

    First kind and second kind are duals, right? One to compute covariant geometry, other one to compute contravariant geometry.
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    Undergrad Raising & Lowering Indices: Q&A on Relativity

    https://rpubs.com/lizhi1800/Einstein_Notation Subscript and superscript are for covariant and contravariant components. They are to tell people the summation result is contravariant or covariant.