Einstein's General Relativity equation: Difference between revisions

From The Portal Wiki
No edit summary
No edit summary
Line 13: Line 13:


== Discussion: ==
== Discussion: ==
* Until we create visualizations maybe we can use this as a placeholder. [https://www.youtube.com/watch?v=UfThVvBWZxM|Einstein's Field Equations of General Relativity Explained]

Revision as of 11:03, 26 April 2020

Albert Einstein (b. 1879)

General relativity 1915

Using the equivalence principle, this tensor is readily generalized to curved spacetime. Drawing further upon the analogy with geometric Newtonian gravity, it is natural to assume that the field equation for gravity relates this tensor and the Ricci tensor, which describes a particular class of tidal effects: the change in volume for a small cloud of test particles that are initially at rest, and then fall freely. In special relativity, conservation of energy–momentum corresponds to the statement that the energy–momentum tensor is divergence-free. This formula, too, is readily generalized to curved spacetime by replacing partial derivatives with their curved-manifold counterparts, covariant derivatives studied in differential geometry. With this additional condition—the covariant divergence of the energy–momentum tensor, and hence of whatever is on the other side of the equation, is zero— the simplest set of equations are what are called Einstein's (field) equations:

$$R_{\mu v}-\frac{1}{2}Rg_{\mu v} = 8 \pi T_{\mu v}$$

Resources:

Discussion: