Newton's water bucket explanation (relativity)?

Question

I've read a few books, but none of which said there is an existing answer for this...

A bucket filled with water hangs on a string. When nothing moves the water is flat. The bucket starts spinning, water is still flat. Water catches up in speed, water starts to funnel out. Bucket stops spinning, water keeps spinning and is still funneling.

Ok, so if you're still with me....
when nothing moves, relative to each other neither the water nor the bucket are moving. and the water is flat. however, when both are moving, they are not moving relative to each other, but the water is funneling (forms a cone)

On the second case. When the bucket starts spinning, it IS moving relative to the water, but the water is flat. But when the bucket stops, it STILL IS moving relative to the water, but the water is funnelled.

If everything is relative, what are these two things moving relative to, it can't be one another. Can it?

Riddle me that. Thanks

Answer 1

Actually this example of the water bucket has been explained thouroughly by Einstein. The reason this water bucket example does NOT obey "relativity" is because it's rotational motion, and therefore there is change in direction of velocity and hence there is acceleration. Hence the rules of relativity don't apply, since it's non-uniform motion.

PS - a rotating object is constantly changing its frame of reference

Answer 2

From Newton's Principia:-
I do not define time, space, place, and motion, as they are well known to all. Absolute space by its own nature, without reference to anything external, always remains similar and unmovable.

Hey was speaking in reference to absolute space:

Definition:
The concept of absolute time and absolute space are hypothetical models in which time either runs at the same rate for all the observers in the universe or the rate of time of each observer can be scaled to the "absolute time" by multiplying the rate by a constant. Similarly the notion of absolute space says that space is an inert arena on which other physical phenomena take place. The space affects the other phenomena, but the space itself is not affected by those phenomena. Absolute space underlies the laws of classical physics of Isaac Newton. Newton's absolute space implies that there is one inertial system out of an infinite number that is unique.

These separate concepts were common in physical theory prior to the advent of special relativity theory, which united the two and showed both to be relativistic. In his theories, the idea of the absolute time and space was superseded by the notion of spacetime in special relativity and especially dynamically curved spacetime in general relativity.

Answer 3

This thought experiment would tend to say that there is an absolute rotational frame of reference in the universe, but it still does not say there is an absolute translation or positional frame of reference in the universe. In other words, direction is absolute but position is relative.

Answer 4

Get what out, the bathtub finished of water; or the water interior the bathtub??! Methinks i'm onto something. placed the bucket the different way up, stability the spoon on good and drink a cup of water.