Timeline for Why does it make sense to do Dyson Resummation with first-order 1PI-diagrams?
Current License: CC BY-SA 4.0
7 events
| when toggle format | what | by | license | comment | |
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| Jul 22, 2023 at 15:06 | comment | added | Lenard Kasselmann | Yes, this makes perfect sense to me now. It's just very unusual that an expression can be brought into a more convenient form by including higher-order terms. Usually it's the other way around :D | |
| Jul 22, 2023 at 14:31 | comment | added | Ghorbalchov | Also note for example that the Taylor expansion of $\frac{1}{x-a}$ is just $\frac{1}{x}+\frac{1}{x}a\frac{1}{x}$ to first order. So the effect of adding on all the other higher order terms in a geometric series is just for illustrative purposes and they don't actually do anything to the result. | |
| Jul 22, 2023 at 14:24 | comment | added | Ghorbalchov | Yes, that sounds right to me | |
| Jul 22, 2023 at 14:21 | comment | added | Lenard Kasselmann | Thanks a lot! So in other words: If we only consider the first order, we can add and subtract higher-order contributions as we like, because by design, these won't change the first-order result. | |
| Jul 22, 2023 at 14:19 | comment | added | Ghorbalchov | I have now corrected the original question as well to be in line with this answer. | |
| Jul 22, 2023 at 14:17 | vote | accept | Lenard Kasselmann | ||
| Jul 22, 2023 at 14:12 | history | answered | Ghorbalchov | CC BY-SA 4.0 |