Just jaunt superquantumly to another quantum world instead of superluminally to an unobservable galaxy. What about these two physically impossible counterfactuals is less than perfectly isomorphic? Except for some mere ease of false-to-fact visualization inside a human imagination that finds it easier to track nonexistent imaginary Newtonian billiard balls than existent quantum clouds of amplitude, with the latter case, in reality, covering both unobservable galaxies distant in space and unobservable galaxies distant in phase space.
One big difference is that there are theoretical cracks in the lightspeed wall that don’t have any go-to-another-quantum-world analog. The Alcubierre solution to the field equations is a thing, after all. More importantly for this discussion, we can construct thought experiments about superluminal travel that have truth conditions because we know what a starfield would look like from N lightyears thataway. Quantumporting doesn’t have analogues of either of those things.
But that’s kind of a distraction. The interesting question for this discussion is how, if at all, the two claims “galaxies receding outside our light cone continue to exist” and “Russell’s teapot exists” are different. I think we agree that there is a predictivist account of “teapot”.
You assert that a predictivist definition of meaning and truth value cannot sustain an account of the “galaxies” claim, and that predictivism is therefore insufficient. I, a predictivist, deny your assertion—you have smuggled in an assumption that predictivists somehow aren’t allowed to assign meaning to counterfactuals that violate physical law, which I (a predictivist) am quite willing to do as long as hypotheically violating that physical law would not bar us from being able to cash out a truth claim in expected experiences.
I believe I am a predictivist who understands predictivism correctly and consistently. I believe you are a predictivist in practice who has failed to understand predictivism in theory.
How can we investigate, confirm, or refute these claims?
One big difference is that there are theoretical cracks in the lightspeed wall that don’t have any go-to-another-quantum-world analog.
In that case the conclusion would be that we don’t know whether or not galaxies outside of the light cone exist and whether or not they exist depend on whether the theoretical cracks actually allowing faster-then-light travel.
Eliezers position seems to be that they exist whether or not faster-then-light travel is possible.
Or are you saying that in a world where a person is certain about all physical laws that exist and there’s no faster-then-light travel, the other galaxies don’t exist for that person while they do exist for people with less knowledge about physics?
Just jaunt superquantumly to another quantum world instead of superluminally to an unobservable galaxy. What about these two physically impossible counterfactuals is less than perfectly isomorphic? Except for some mere ease of false-to-fact visualization inside a human imagination that finds it easier to track nonexistent imaginary Newtonian billiard balls than existent quantum clouds of amplitude, with the latter case, in reality, covering both unobservable galaxies distant in space and unobservable galaxies distant in phase space.
One big difference is that there are theoretical cracks in the lightspeed wall that don’t have any go-to-another-quantum-world analog. The Alcubierre solution to the field equations is a thing, after all. More importantly for this discussion, we can construct thought experiments about superluminal travel that have truth conditions because we know what a starfield would look like from N lightyears thataway. Quantumporting doesn’t have analogues of either of those things.
But that’s kind of a distraction. The interesting question for this discussion is how, if at all, the two claims “galaxies receding outside our light cone continue to exist” and “Russell’s teapot exists” are different. I think we agree that there is a predictivist account of “teapot”.
You assert that a predictivist definition of meaning and truth value cannot sustain an account of the “galaxies” claim, and that predictivism is therefore insufficient. I, a predictivist, deny your assertion—you have smuggled in an assumption that predictivists somehow aren’t allowed to assign meaning to counterfactuals that violate physical law, which I (a predictivist) am quite willing to do as long as hypotheically violating that physical law would not bar us from being able to cash out a truth claim in expected experiences.
I believe I am a predictivist who understands predictivism correctly and consistently. I believe you are a predictivist in practice who has failed to understand predictivism in theory.
How can we investigate, confirm, or refute these claims?
In that case the conclusion would be that we don’t know whether or not galaxies outside of the light cone exist and whether or not they exist depend on whether the theoretical cracks actually allowing faster-then-light travel.
Eliezers position seems to be that they exist whether or not faster-then-light travel is possible.
Or are you saying that in a world where a person is certain about all physical laws that exist and there’s no faster-then-light travel, the other galaxies don’t exist for that person while they do exist for people with less knowledge about physics?