Trace
The trace of the Einstein tensor can be computed by contracting the equation in the definition with the metric tensor . In dimensions (of arbitrary signature):
The special case of 4 dimensions in physics (3 space, 1 time) gives, the trace of the Einstein tensor, as the negative of, the Ricci tensor's trace. Thus another name for the Einstein tensor is the trace-reversed Ricci tensor.
Read more about this topic: Einstein Tensor
Famous quotes containing the word trace:
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—Eugène Ionesco (b. 1912)
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—Max Frisch (1911–1991)
“Of moral purpose I see no trace in Nature. That is an article of exclusively human manufacture—and very much to our credit.”
—Thomas Henry Huxley (1825–95)