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Exactly.

Any good scientific theory must create falsifiable hypotheses.

Otherwise it’s just a nice story.

>Any good scientific theory must create falsifiable hypotheses.

For any behavior inside the world, this is good.

But for the world itself and what harbor's it, asking for falsifiability is like measuring the expansion of space using a ruler that inhabits the same space.

Even science, that works in terms of cause and affect, which implies space and time, cannot be used to describe space and time itself.

Vanilla "scientists" have been trying to do that, but that is a dead end.

> But for the world itself and what harbor's it, asking for falsifiability is like measuring the expansion of space using a ruler that inhabits the same space.

Which exactly is what general relativity is centrally about and the reason why general relativity is defined in terms of intrinsic properties of the Einstein manifold describing the space of the universe. Intrinsic properties are, colloquially, indeed properties that can be measured "using a ruler that inhabits the same space".

Gauß' Theorema Egregium [1] is an early predecessor of intrinsic properties of general manifolds, and says that the curvature of a surface can indeed be "be determined entirely by measuring angles, distances and their rates of change on a surface, without reference to the particular manner in which the surface is embedded in the ambient 3-dimensional Euclidean space" ([1]).

[1] https://en.wikipedia.org/w/index.php?title=Theorema_Egregium...

Also why LIGO works but Michelson-Morley failed: you can use the ruler distortion as a signal, with some caveats.

In LIGO, we detect the far away distortions propagating through our rulers and the differential effect of those waves.

But Michelson-Morley failed because the ruler distorted synchronously with the signal we tried to measure — since we mistakenly believed EM and matter were different fields.

How are general-relativistic effects relevant for the outcome of the Michelson-Morley experiment?
> How are general-relativistic effects relevant for the outcome of the Michelson-Morley experiment?

General-relativistic effects are relevant for the outcome of the Michelson-Morley experiment in the sense that the general theory of relativity is a generalization of the special theory of relativity. :-)

Otherwise: the additional predictions that the general theory of relativity makes about gravity, curvature of space etc. are not relevant for the outcome of the Michelson-Morley experiment.

I mean, if you're claiming that general relativity is relevant here, then you need to show that quantitatively.
What do you mean?

You seem to think I’ve said something very technical, while I’ve merely pointed out a well-known effect of Lorentz invariance and interferometry: you can’t detect an “aether” signal coincident with the detector, because the detector is distorted synchronously.

Michelson-Morley was never going to work because it relied on the assumption matter wasn’t subject to aether wind — which turned out to be wrong, as matter is subject to relativistic effects and fields unify. You needed that independence to generate the differential the interferometry amplified.

By contrast, LIGO measures an effect far removed and not co-moving with the detector. So it works.

> measuring the expansion of space using a ruler that inhabits the same space

We do that, routinely: that’s how we do cosmology.

> We do that, routinely:

Yea, that is why we are not getting any where...

> Yea, that is why we are not getting any where...

Which alternative way of doing measurements do you propose? As far as I know, measuring intrinsic properties, i.e. "using a ruler that inhabits the same space" is with our current technology the only possible way of doing measurements.

Assuming that we are trying to understand the ground truth about existence by doing these measurements, may be we can acknowledge the limitation and stop trying to do it. Then we can be open minded and stop being hung up of the idea of "falsifiability", and could come up with or give more consideration to radically different hypothesis that we might come up with alternative measurements that we could make, that can prove or disprove them.
So time extending into the future is not a useful hypothesis? Space continuing beyond the cosmic horizon is not a useful hypothesis? The past entropy of the past being arbitrarily low (vs what is essentially last tuesdayism) is not a useful hypothesis?
Time extending into the future is validated by direct experience.

A continuum of variants of myself is bought.

What is the value of assuming that literally every possible trajectory actually happens, but somehow I am only in one of them, while also being a continuum of other ones? If everything is true, than nothing is true.

If time did not continue into the future, it would not be observable. Therefore hypothesis that it will continue to do so is not disprovable.

As far as multiverse goes, there isn't any inherit value in assuming that the wavefunction as given actually happens, it's just a simpler explanation than trying to come up with (arguable unprovable) ways to cull the wavefunction.