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Bucket argument (wikipedia.org)
29 points by canjobear 4 months ago | hide | past | favorite | 16 comments



Comprehensive argument for why this is a red herring:

https://reasonandliberty.com/articles/newtons_bucket


I'm not sure that logical/abstract argument is the right way to progress on this.. seems like it really isn't abstract and must eventually be something that would need to be measured and compared to prediction in order to decide whether it's a good model/theory or not. (And we're not able to actually measure sensitively-enough to detect this level yet AFAIK) Michelson-Morley interferometer experiment has also been revisited with quite different conclusions that don't rule out substance-of-space too IIUC.

I think that this might be a topic that's worth staying mostly-undecided-about.. despite all the strong opinions around! The fields of QM have to exist within something right?


Interesting that Descartes took the other side of Newton on this, and turned out to be correct.



I just finished reading a book that used this example (and the concept of absolute space) as part of their theory of the universe: an inviscid fluid made up of quanta, or discrete energy vortices. Brilliant book.

https://www.amazon.com/Einsteins-Intuition-Visualizing-Natur...


Not sure why this was posted, but this is a concept from Newton that we know to be an oversimplification.


Not sure if you’re trolling, but how would one expect Newton to not deliver the most simplistic explanation of something no one else had bothered to think up yet? Since every thought on the theory since Newton proposed it would therefore be a more complete theory because something from the next party’s ponderings to be added to the original theory…


I just wasn't sure why an article on Newtonian physics was posted.

I clicked through because I was interested to see if there was some new argument for absolute space, which would contradict our current understanding (unlikely). It was not, however. Instead it was a nuance of Newton's arguments for his basis of absolute space.


Einstein was deeply concerned with Newton's bucket, correspondence over it is mentioned many times in Isaacson's biography of him but I don't remember the resolutions he came to or if it was prior to general relativity.


How does modern physics address the argument?


Due to the pressure in the water being higher than in the center (the momentum of an individual molecule forces it outwards), a higher column of water is supported at the rim.

The speeds involved are not relativistic, so this isn't a matter of special or general relativity. Except, of course, one needs to explain the conservation of momentum relative to the universe. Noether said that's because space is isotropic.


Modern physics tells us there is no absolute space. Instead, there are geodesics in spacetime (General Relativity). The article points this out.


I think there are a few 'fringe' modern-ish physics projects that actually do suggest that space could be made from something, and can flow (which can provide an explanation for gravity and relativity) Reg Cahill's "Process Physics" (from a while back) had a good crack at this I reckon and more recently Wolfram's work around graph-rewriting operations as a model for fundamental-space.. which sounded like it went pretty well!


How do geodesics address the argument?


The argument is incomplete, and therefore incorrect (as the article points out).

Geodesics in spacetime address the nature of motion through space and time.


I have difficulty seeing the difficulty of what's happening, or I'm missing the point. I see the situation in a similar way as objects of different weights falling at the same rate--if we think of the object as composed of many independent particles which are affected.

For the case of the water in the pail, each water 'particle' is moving linearly until it bumps into the wall of the pail which diverts it toward the center of the pail. This action causes accumulation near the wall. The same could be done without gravity and water would start as a disk perpendicular to a cylindrical wall then become a ring with the most spread out parts up against the cylinder wall. We can also replace gravity in the pail experiment with linear acceleration, as per the elevator thought experiment.

Edit: I guess the bit I'm not considering is if the local frame is rotating, and the pail appearing to rotate with respect to it, could the water be flat if the pail was non-rotating in the absolute frame? Seems really weird to picture it, but we could measure the radial acceleration of everything except the pail of water to see what's what.




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