In the previous post, I mentioned some technical evidence that string theory is the right approach to quantum gravity (namely that the threshold to preserve "cosmic censorship" of naked singularities, is provided by the weak gravity conjecture). Another example of such evidence is that string theory predicts the same corrections to black hole entropy, as the semiclassical approach to Euclidean quantum gravity.
On the other hand, asymptotic safety did manage to predict the Higgs boson mass, and apparently passed one technical test that it shouldn't have (the two-loop counterterm). And on the empirical side, MOND makes a few successful predictions that don't come naturally from dark matter.
Meanwhile, we have a new theoretical contender: "geometric unity", finally the subject of a technical paper this year, after years of secrecy. GU's creator is using his theory as part of a very public attempt to create an Internet-based intellectual counter-establishment outside of academic groupthink, so it's a little controversial.
Nonetheless, now there's a paper, it is possible to judge the theory on its own merits. I can report that it's based on a few nice concepts, but it remains to be shown that the concepts can be realized mathematically. (There is already a "response to GU" paper which doesn't engage with the core ideas, but does state some of the technical barriers that will need to be overcome.)
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