In this talk with Edge's John Brockman, Julian Barbour takes on the absolute framework of time.
And if time truly doesn't exist, could we, hypothetically, live forever?
Julian Barbour said that:
- One of the great questions in physics is whether there's some sort of invisible framework in which everything unfolds, Julian Barbour says in a talk with Edge's John Brockman. Newton introduced the notions of absolute space and absolute time. Absolute space is like a translucent glass block that stretches from infinity to infinity; it's a fixed frame of reference in which everything happens. Newtonian time is like some invisible river that flows uniformly for ever. The trouble with this is that we can't see this invisible framework, all we see are things moving relative to each other.
This is the relational viewpoint, as opposed to the absolute viewpoint of Newton...
- My basic idea is that time as such does not exist. There is no invisible river of time. But there are things that you could call instants of time, or "Nows".
As we live, we seem to move through a succession of "Nows", and the question is, what are they?
They are arrangements of everything in the universe relative to each other in any moment, for example, now.
- We have the strong impression
that you and I are sitting opposite each other,
that there's a bunch of flowers on the table,
that there's a chair there
and things like that -
they are there in definite positions relative to each other.
I aim to abstract away everything we cannot see... and simply keep this idea of many different things coexisting at once in a definite mutual relationship. The interconnected totality becomes my basic thing, a "Now". There are many such Nows, all different from each other...
- ...If you try to get your hands on time, it's always slipping through your fingers. People are sure that it's there but they can't get hold of it. Now my feeling is that they can't get hold of it is because it isn't there at all. That what we think is the flow of time - and even seeing motion - is actually an illusion...
- Let's take a simple model; suppose there were just three particles in the universe and nothing else. In some instant they would be in certain positions relative to each other and would form some triangle. Newton claimed that this triangle has in addition some position in absolute space and that it's changing in time. What I'm saying is that there isn't any of that external framework of space and time, there's just the possible triangles that the particles form. The triangles do not occur somewhere in absolute space at some instant of time, some "Now". The triangles are the "Nows"...
- If we had a universe with a million particles in it there would be some relative configuration of those million particles and nothing else. That would form one "Now", and all the different ways you could arrange all the million particles would make all the different possible "Nows"...
- That's my ontology of the universe - there are Nows, nothing more, nothing less...
Democritus: Read more!