Theory of Everything?

I already said this is NOT Newton’s absolute space, but rather space substantivalism. The spacetime version is rejected by Einstein not because of logical positivism/verificationism, but rather the hole argument. A majority (but definitely not all) of physicists are convinced by the hole argument, and agree with Einstein that spacetime subtantivalism is false. I myself am not convinced one way or the other.

Regardless, this has nothing to do with Newton’s absolute space, which goes back to the problem in this entire discussion that you don’t even know what Newton’s absolute space even is…

That’s all I want to add. Next time maybe learn the subject first before arguing it with someone.

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I’ve enjoyed following this exchange, mostly because I learn a lot from PdotdQ’s posts on physics so I appreciate how your posts have led to him saying more.

From reading your posts, I suspect you and he differ on an a basic assumption which I have not seen mentioned explicitly. It is this question:

How should our best physics constrain our metaphysics of space and time?

I think PdotdQ and almost all philosophers believe that our metaphysics must be consistent with our best science. With this in mind, Newton’s concept of absolute space cannot be used for an ontology of space. You are correct that there is no general agreement in philosophy about what the ontology of space is; but whatever it is, philosophers agree it must be consistent with what we have learned about reality from our best physics.

You seem to think that metaphysics proceeds independently of science. If so, that would be why you do not see the point of PdotdQ’s posts.

PdotdQ has explained absolute space using advanced mathematics; that math much too advanced for me. Instead, I have found the following helpful; they require much less mathematics. The Maudlin book is a very nice introduction to the philosophical issues and the related physics, should you want to invest more time in these.

I don’t plan to contribute further to this thread.

https://plato.stanford.edu/entries/spacetime-iframes/

https://plato.stanford.edu/entries/spacetime-theories/
(esp section 4 and later for the above)

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I’m a physics hobbyist, so I may get this wrong . . .

The speed of light seems to be an important thing to look at. From all experimentation we have looked at, the speed of light is the same in all frames of reference. If there was an absolute frame of reference that everything is compared to, then the speed of light should be different in all but one frame of reference.

This is why I asked you before if there were experiments that we could run on a spaceship to tell us if the spaceship was moving or not. If the spaceship was the only thing in the universe, how would you determine its velocity if you have no knowledge of any past acceleration that has acted on the spaceship? If you measured the speed of light on that spaceship it would be the standard 3E8 m/s, would it not? In fact, the speed of light will not change even after you accelerate the ship and start coasting through space.

Now let’s add another spaceship in our empty universe. You wake up and look out the window of the spaceship. You see a spaceship hurtling towards you. A passenger in the other spaceship observes the very same thing. So who is moving? Are you both moving? You shoot a 588 nm laser out the window and the passenger in the other spacship measures it as 500 nm. Who is right? Is the wavelength of the laser 588 or 500 nm? You both measure the speed of the laser light at 3E8 m/s, but the spaceships are moving towards one another. How does that work?