The Man Who Corrected Einstein

From Minute Physics.

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This video is about how Russian physicist Aleksandr Fridman corrected Albert Einstein about the expansion of the universe. Einstein thought that general relativity implied that space had to be static and unchanging, but he had made a technical error regarding the differentiation of the metric (in particular, I believe he mistook the determinant of the metric for a scalar rather than a tensor density of weight 2). Friedmann didn’t make this differential geometric mistake, and the cosmologies he found from the Einstein Equations were more varied in their properties – they could be expanding, or contracting, or (with the cosmological constant), static.

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Alexander Friedmann

Einstein Wrongly Criticizes Alexander Friedmann

Alexander Friedmann Corrects Einstein

Einstein Admits his Mathematical Mistake

Interrogating the Legend of Einstein’s “Biggest Blunder”

Cosmological Considerations in the General Theory of Relativity

On the General Theory of Relativity (Einstein)

The Field Equations of Gravitation

The Einstein Field Equations

Presentation about the Sequence of Events

Tensor Densities:

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Created by Henry Reich