# If reality is relative, then what about Newton's bucket argument?

There is nothing outside the universe. - Lee Smolin

So, there can't be any absolute frame. Everything must be measured relative to an entity that exists in the universe. Thus, space is relative. But, what about the Bucket argument that Newton proposed in favour of his absolute rotation theory? Can a relationist explain the Bucket Argument? If reality is relative how to disprove Newton's Bucket Argument that establish Absolute rotation?

• The bucket argument merely shows that a rotating frame of reference is non-inertial. Nothing to see here. Move on. – John Dvorak Dec 27 '14 at 8:37
• The Wikipedia article you (attepmt to) link explains things pretty well, actually. – John Dvorak Dec 27 '14 at 8:42
• Moreover, if you're worried about relativities of rotating frames, then General Relativity actually tells the difference between the frame where the bucket is rotating and a relatively rotating frame wherein the bucket is still. At most one of these frames is inertial, and it is the frame wherein a fixed bucket has a flat surface. Acceleration, in the sense of what an accelerometer measures, is absolute in General Relativity: it is a fallacy that "relativity teaches us that everything is relative". – WetSavannaAnimal Dec 27 '14 at 8:50
• @user36790 Wow! In the times of Newton the Wikipedia already existed? I pressed on your words "Bucket argument", and what I found was "Donate to Wikipedia !" – Sofia Dec 27 '14 at 9:30
• Newton could have done his experiment with the bucket and water, while walking toward the College. Both for him and for a person at rest, the water would appear as rising toward the sides of the pail. – Sofia Dec 27 '14 at 10:04