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marcus

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## Main Question or Discussion Point

Quote from page 1 of paper posted by Hossenfelder today:

"These difficulties can be circumvented by changing the quantization condition in such a way that gravity can be perturbatively quantized at low energies, but at energies above the Planck energy – energies so high that the perturbative expansion would break down – it becomes classical and decouples from the matter fields. The mechanism for this is making Planck’s constant into a field that undergoes symmetry breaking and induces a transition from classical to quantum. In three dimensions, Newton’s constant is G = [STRIKE]h[/STRIKE]c/m

1208.5874

this paper is a bold bid to cut the Gordian knot and I find it remarkably persuasive.

I would like to think of Newton's G as, in fact, just [STRIKE]h[/STRIKE]c/m

One can imagine that nature wanted it this way So maybe this way of joining quantum geometry to QFT and the standard particle model will yield predictions that are practical to test!

I'm hopeful about this idea. Good for Hossenfelder!

"These difficulties can be circumvented by changing the quantization condition in such a way that gravity can be perturbatively quantized at low energies, but at energies above the Planck energy – energies so high that the perturbative expansion would break down – it becomes classical and decouples from the matter fields. The mechanism for this is making Planck’s constant into a field that undergoes symmetry breaking and induces a transition from classical to quantum. In three dimensions, Newton’s constant is G = [STRIKE]h[/STRIKE]c/m

^{2}_{Pl}, so if we keep mass units fixed, G will go to zero together with [STRIKE]h[/STRIKE], thus decoupling gravity. It should be emphasized that the ansatz proposed here does not renormalize perturbatively quantized gravity, but rather replaces it with a different theory that however reproduces the perturbative quantization at low..."1208.5874

this paper is a bold bid to cut the Gordian knot and I find it remarkably persuasive.

I would like to think of Newton's G as, in fact, just [STRIKE]h[/STRIKE]c/m

^{2}_{Pl}. With a fixed standard mass. Since [STRIKE]h[/STRIKE]c is a standard force-area quantity---a standard amount of inverse-square coupling---G just says that two standard masses have that much interaction. So then if [STRIKE]h[/STRIKE] goes to zero at high energy then obviously so must G → 0.One can imagine that nature wanted it this way So maybe this way of joining quantum geometry to QFT and the standard particle model will yield predictions that are practical to test!

I'm hopeful about this idea. Good for Hossenfelder!

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