How we know that Einstein's General Relativity can't be quite right
In the How we know that Einstein's General Relativity can't be quite right video, Sabine Hossenfelder explains how General relativity cannot be quite right. One claim in the video is that (general) relativity is wrong because relativity conflicts with quantum mechanics (QM) and QM is right. That is a bold claim for a falsifiable theory. A two-split thought experiment is provided to show this. This experiment – and to my knowledge no experiments so far – does not combine relativity and QM in such a way that we can rule out one of them. I do agree that theories with singularities, like relativity, generally suggest problems. Both theories, have shown to be reliable so far and naturally: both cannot be proven correct. I think that therefore, using one theory contradicting another cannot be used as proof that the other must be wrong.
Both general relativity (GR) and quantum mechanics (QM) are falsifiable theories that can only be disproved even though so far, they both explain and predict what we measure good enough.
The claim of this video, however, seems to be that GR is wrong, because it conflicts with QM and QM is right. That is a bold claim! I therefore have some questions, that are related to the two-slit experiment. I might be completely wrong in the stories that lead up to these questions but I am eager to learn!
For as far as I know, experiments are always carried out in a frame of reference that, for all practical purposes, has uniform acceleration at most. This means that the uncertainty in the "position" of the electrons (whatever that means) would not lead to different "forces" or in other words, there would never be observable tidal forces to affect an outcome whether the electron would be a sizable cloud or a point mass. The geometry "dent" caused by the electron itself is probably also irrelevant. Not only because it is very small, but also – and this is admittedly speculation – because whatever shape the "position" of the electron takes, the associated mass-density would probably cause curvature that would be neutral to the experiment. At some point we do measure the electron and then all observers agree on resulting curvature anyway. If we can make the contribution of gravitation in this experiment relevant, I think I'd rather be somewhere else. For these reasons, I think this experiment cannot lead to the conclusion that GR is wrong. (Though I do think singularities are suspect)
So the first question is: Do you agree that the used two-slit experiment cannot be used to "disprove" GR? If not, I am eager to learn how it does!
Is it theoretically possible to measure the geometry curvature that is caused by the electron in transit, without disturbing it? Would vagueness of the curvature scale with the vagueness of our knowledge considering the whereabouts of the electron? I think that it is too simple to suppose that GM or QM is more true than the other or that QM will be able to fully explain GM.
Do you agree that both theories are incomplete and to unify them we need to hold up to scrutiny all the interpretations of these theories? Especially those that lead up to often drawn conclusions like "there is no instantaneous causality in relativity"?