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Could someone explain this sentence? > On the most trivial level, we can infer the mass and charge of a particle from its gravitational field. How does gravit
by dataflow 1y ago
Could someone explain this sentence?
> On the most trivial level, we can infer the mass and charge of a particle from its gravitational field.
How does gravity tell you the charge of a particle? I didn't even know it carries information about the sign of the charge, let alone the magnitude.
- ur-whale 1y agoYeah, wondering the same thing. And there quite a lot of other statements in the paper presented as "obvious" that are IMO everything but.
- antognini 1y agoI'm guessing the idea is that in GR, the solution for a black hole with charge looks different from one without. So in principle you could infer the charge of a black hole based on the curvature of spacetime.
- hammock 1y agoAnd same logic applies to all masses, not only black holes. It’s just nearly impossible to calculate for anything besides a black hole, for a variety of reasons. Also, the reference to “known links between the solutions of Yang-Mills theory and those of gravity” (Y-M equations describing charge and EM field) seems to speculatively imply that charge-related information is encoded in the geometry of spacetime, alongside gravitational effects
- dataflow 1y agoThat's way over my head, sorry. How does the solution differ gravitationally, if the black hole isn't spinning? And how are positive and negative charges distinguished?
- deleted 1y ago[deleted]
- Qem 1y ago> How does gravity tell you the charge of a particle? Perhaps you can just assume a radius where the electron self-repulsion energy equals its own mass, by m = E/(c^2).
- AnimalMuppet 1y agoEven if you can, that doesn't tell you whether the self-repulsion is due to a positive charge repelling itself, or a negative one.