science

Yeah, there is no consensus on quantum gravity. There are competing theories, none of which have any viable path to test.

Here's the abstract from a paper from last year at https://arxiv.org/pdf/gr-qc/0601043 (PDF, unfortunately):

Freeman Dyson has questioned whether any conceivable experiment in the real universe can detect a single graviton. If not, is it meaningful to talk about gravitons as physical entities? We attempt to answer Dyson’s question and find it is possible concoct an idealized thought experiment capable of detecting one graviton; however, when anything remotely resembling realistic physics is taken into account, detection becomes impossible, indicating that Dyson’s conjecture is very likely true. We also point out several mistakes in the literature dealing with graviton detection and production.

Edit: That said, the paper does address this. They cover a variety of QG theories and try to address the fundamental requirements any theory must meet.

As we do not have a fully consistent theory of quantum gravity, several different axiomatic systems have been proposed to model quantum gravity Witten:1985cc ; Ziaeepour:2021ubo ; Faizal2024 ; bombelli1987spacetime ; Majid:2017bul ; DAriano:2016njq ; Arsiwalla:2021eao . In all these programs, it is assumed a candidate theory of quantum gravity is encoded as a computational formal system

ℱQ​G={ℒQ​G,ΣQ​G,ℛalg}.

It's over my head, personally.