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Comment by PaulHoule | Hacker News Reader

It's not that hard to model gravity with a QFT, there are so many ways to do quantum gravity now. The problem is deciding which one is right and the answer to that might involve looking inside a black hole or at energy scales of 10^19 GeV, length scales of 10^-35m, etc.

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In the classical sense of "a QFT" then no there are no ways to do QG. The computations diverge. In the extended sense where you let yourself include non-QFT-like things like strings and spin foams, then sure.

But the fact that the computation diverges is not a problem by itself. All QFT diverge but this can be fixed by renormalisation. Problem is that for gravity this would require infinity many parameters and the theory could match any observation

My understanding was that renormalization only needs "parameters" when the computational methods are approximate.

I thought the issue was more that we have no idea how to perform appropriate calculations for SM+QG? Maybe I'm wrong?

Incompleteness theorem implies none of them are “right” in a “one true axiomatic model” kind of way.

Each is “right” so long as they are consistent with our consensus driven glyph system that exists to normalize discussion, and should never be taken as a 1:1 model of reality.

The glyph systems are not a pipe.

for those following, LHC reached 13 TeV which is 15 orders of magnitude smaller than 10^19 GeV

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