(December 25, 2022 at 7:55 pm)polymath257 Wrote:(December 25, 2022 at 3:34 pm)Jehanne Wrote: Do you think that Dark Energy is a constant? If not, maybe it will reverse and become attractive??
Without a good theory of quantum gravity, we simply don't even have a good explanation for the cosmological constant at all. It's been said that the prediction for the value was 'only' off by 120 *orders of magnitude*.
In other words, nobody has any real idea.
The toolkit for quantizing classical forces doesn't work with gravitons because they are not perturbatively renormalizable (I know you know that). Superstring theory gave it a shot but we're not seeing even the lightest SUSY particles at the LHC. Loop Quantum Gravity made a prediction that never materialized experimentally (c being to a small degree dependent on photon wavelength). The best hope for even demonstrating gravity is quantum at all is by looking at big molecules in superposition but we're not there yet.
All that said, why do we seek an "explanation" for a constant? No one explained the magnitude of G or c or h bar, they just read it off the dial.
