Timeline for How find out the expression of Einstein tensor?
Current License: CC BY-SA 4.0
10 events
| when toggle format | what | by | license | comment | |
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| Mar 13, 2021 at 10:32 | comment | added | Mozibur Ullah | @Nik: If you don't know how to raise and lower an index by use of the metric you should go back and revise this before going on to tackle more complex questions as these operations are used without explanation everywhere. Basically $G^{\alpha}_{\beta} = g^{\alpha\gamma}.G_{\gamma\beta}$ here $g$ is the metric. There are two forms, $g^{\alpha\gamma}$ and $g_{\alpha\gamma}$ amd they are inverses of each other. | |
| Mar 13, 2021 at 9:14 | answer | added | Noone | timeline score: 1 | |
| Mar 13, 2021 at 9:06 | answer | added | Free_ion | timeline score: 0 | |
| Mar 13, 2021 at 9:05 | history | edited | Qmechanic♦ | CC BY-SA 4.0 |
edited tags; edited title
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| Mar 13, 2021 at 8:44 | comment | added | Nihar Karve | Compute the unique Christoffel symbols, then the Riemann curvature tensor, then the Ricci tensor and the Ricci scalar, with which you construct $G_{\mu\nu}$ (I don't think there's a simpler way). Once you have $G_{\mu\nu}$, you can raise the index by doing standard matrix multiplication with the inverse metric | |
| Mar 13, 2021 at 8:43 | review | First posts | |||
| Mar 13, 2021 at 10:00 | |||||
| Mar 13, 2021 at 8:42 | comment | added | Nik | Above all how I can pass then form $G_{\mu\nu}$ to $G_{\mu}^{\nu}$? | |
| Mar 13, 2021 at 8:42 | comment | added | Nik | Yes maybe, but I am very confused..I can't understand how...can you give me even only an hint on how starting? | |
| Mar 13, 2021 at 8:39 | comment | added | Nihar Karve | You just have to brute force calculate $G_{\mu\nu}\equiv R_{\mu\nu}+\frac12 Rg_{\mu\nu}$ | |
| Mar 13, 2021 at 8:32 | history | asked | Nik | CC BY-SA 4.0 |