No, MWI does not have varying constants. Cosmological inflation seems to be about a changing cosmological constant. I think “eternal inflation” is an elaboration emphasizing more variation of the parameters.
Added: No, that’s not quite right. Inflation is the pretty much empirical claim that the cosmological constant has changed. That strongly implies that other parameters can change. But do they change enough in interesting ways? Chaotic/eternal inflation is a dynamic theory about how the cosmological constant changes. It implies that the universe is very big, so the other parameters have room to run wild.
Equivocating between MWI and inflation, as in your dialogue, is bad.* But asking whether a specific argument is bad is usually a wrong question. I think your dialogue is a confused memory of a coherent argument. Inflation is pretty much accepted and that is definitely evidence for chaotic inflation, although perhaps quite weak evidence. And chaotic inflation is pretty much the right multiverse for the full argument.
* Maybe that is the fault of Tegmark, who calls MWI a multiverse, unlike most people; but, as Viliam notes, he does make some anthropic fine-tuning arguments via MWI and ordinary inflation.
No, MWI does not have varying constants. Cosmological inflation seems to be about a changing cosmological constant. I think “eternal inflation” is an elaboration emphasizing more variation of the parameters.
Added: No, that’s not quite right. Inflation is the pretty much empirical claim that the cosmological constant has changed. That strongly implies that other parameters can change. But do they change enough in interesting ways? Chaotic/eternal inflation is a dynamic theory about how the cosmological constant changes. It implies that the universe is very big, so the other parameters have room to run wild.
So, this is a bad rebuttal to the fine-tuning argument, no?
Equivocating between MWI and inflation, as in your dialogue, is bad.* But asking whether a specific argument is bad is usually a wrong question. I think your dialogue is a confused memory of a coherent argument. Inflation is pretty much accepted and that is definitely evidence for chaotic inflation, although perhaps quite weak evidence. And chaotic inflation is pretty much the right multiverse for the full argument.
* Maybe that is the fault of Tegmark, who calls MWI a multiverse, unlike most people; but, as Viliam notes, he does make some anthropic fine-tuning arguments via MWI and ordinary inflation.