> That the three methods disagree “is not telling us about fundamental physics,” Freedman said. “That’s telling us there’s some systematic [error] in one or more of the distance methods.”
What she means is that the bar for proving that this is an error in physics is much higher than that of proving that it's a measurement error. Like, if you're measuring acceleration due to gravity, and your sensor/calculation gives you 5m/s^2 rather than the real ~9.81m/s^2 that everything else measures, you can't immediately resort to arguing that physics is wrong, you have to rule out that your sensor/calculation is wrong first.
To argue that the physics is wrong, you are likely to be arguing that very well tested theories like general relativity, special relativity or electromagnetism are off in some way. That's a much higher bar than just the measurements of either the ladder or CMB being wrong in some way.
to add to this, it's equivalent to the difference between trying to justify that one experiment (or one class of experiments) is wrong vs several dozens of classes of thousands of experiments are all subtly wrong so that this one experiment can be right.
And in this case, your sensor isn't giving a wildly wrong answer like 5 m/s^2, but rather something close to the correct answer, like 9.15 m/s^2.
It's easy to think up ways that your sensor could be 5-10% off. It's very difficult to come up with an entirely new theory of gravity that explains everything we observe about the world, but also makes gravity a few percent weaker in this one case.
She's saying that a different model -- one of the three disagreeing methods for distance ladder measurements -- must be wrong, because they disagree with each other. But if one or more of those models are wrong, then there's not much evidence that the LambdaCDM model is wrong.
Conversely, the hypothesis that LambdaCDM is wrong does nothing to explain why the distance ladder methods disagree.
She clearly isn't saying that any model is infallible, she's just saying that clear flaws with one set of models throw into question some specific accusations that a different model is wrong.
You actually need to pay attention to the details; the physicists certainly are. Glib contrarianism isn't very useful here.
That researcher has a personal conviction that the model isn't wrong. That is spurring them to spend the years and decades necessary to assemble the experimental evidence to test the model. Either it'll turn out to be wrong or right in the end, but the conviction is what gives that individual researcher the impetus to keep scratching at the problem for a good chunk of their life.
You shouldn't really roll your eyes at that. They're ultimately doing all the work which will prove it right or wrong. They might wind up not liking the answer they get, but the conviction is necessary to get them there because human emotions are weird.
She's following a hunch, it's what scientists do. In this case the hunch is that the model is not wrong. That's a far cry from saying it's impossible to be wrong.
> That the three methods disagree “is not telling us about fundamental physics,” Freedman said. “That’s telling us there’s some systematic [error] in one or more of the distance methods.”
Freedman is saying that the model is not wrong.