Julian Barbour on Time

Julian Barbour writes:Specifically, DeWitt hijacked the Schrdinger equation, named for the great
Austrian physicist who created it. In its original form, the equation reveals how
the arrangement of electrons determines the geometrical shapes of atoms and
molecules. As modified by DeWitt, the equation describes different possible
shapes for the entire universe and the position of everything in it. The key
difference between Schrdinger's quantum and DeWitt's cosmic version of the
equation besides the scale of the things involved is that atoms, over time,
can interact with other atoms and change their energies. But the universe has
nothing to interact with except itself and has only a fixed total energy. Because
the energy of the universe doesn't change with time, the easiest of the many
ways to solve what has become known as the Wheeler-DeWitt equation is to
eliminate time.
Most physicists balk at that solution, believing it couldn't possibly describe the
real universe. But a number of respected theorists, Barbour and Stephen
Hawking among them, take DeWitt's work seriously. Barbour sees it as the
best path to a real theory of everything, even with its staggering implication that
we live in a universe without time, motion, or change of any kind.
Strolling in the meadows of oxford's Christ Church College with Julian Barbour,
time and motion seem undeniable. Towering cumulus clouds float overhead,
ferried by a gentle breeze. Children run and shout in the same field where Alice
Liddell, the girl who inspired Lewis Carroll's Alice's Adventures in
Wonderland, often played. How can there be no time, no movement? Barbour
settles his tall, lean frame into the grass, readying himself for a long explanation
to yet another skeptic. He begins with what seems a most straightforward
proposition: Time is nothing but a measure of the changing positions of objects.
A pendulum swings, the hands on a clock advance. Objects and their
positions he argues, are therefore more fundamental than time. The universe
at any given instant simply consists of many different objects in many different
positions.
That sounds reasonable, as it should, coming from a thoughtful gentleman like
Barbour. But the next part of his argument the crux of his view is much
harder to swallow: Every possible configuration of the universe, past, present,
and future, exists separately and eternally. We don't live in a single universe that
passes through time. Instead, we or many slightly different versions of
ourselves simultaneously inhabit a multitude of static, everlasting tableaux that
include everything in the universe at any given moment. Barbour calls each of
these possible still-life configurations a "Now." Every Now is a complete,
self-contained, timeless, unchanging universe. We mistakenly perceive the
Nows as fleeting, when in fact each one persists forever. Because the word
universe seems too small to encompass all possible Nows, Barbour coined a
new word for it: Platonia. The name honors the ancient Greek philosopher who
argued that reality is composed of eternal and changeless forms, even though
the physical world we perceive through our senses appears to be in constant
flux.

interviewer writes: How does the physics community react to such ideas? Physicists who know
Barbour's work agree that it shouldn't be dismissed out of hand. At a physics
conference in Spain, Barbour conducted an informal poll. He asked how many
of the physicists believed that time would not be a part of a final, complete
description of the universe. A majority were inclined to agree.
Don Page, a cosmologist at the University of Alberta in Edmonton who
frequently collaborates with Stephen Hawking, raised his hand that day. "I think
Julian's work clears up a lot of misconceptions," says Page. "Physicists might
not need time as much as we might have thought before. He is really
questioning the basic nature of time, its nonexistence. You can't make technical
advances if you're stuck in a conceptual muddle." Strangely enough, Page feels
that Barbour might actually be too conservative. When physicists finally iron
out a new theory of the universe, Page suspects that time won't be the only
casualty. "I think space will go too," he says cryptically.

I am curious about your name by the way.

In Barbour's universe, every moment of every individual's life birth, death, and everything in between exists forever. "Each instant we live," Barbour says, "is, in essence, eternal." That means each and every one of us is immortal. Like the perpetually unmoving lovers in Keats's "Ode on a Grecian Urn," we are "for ever panting, and for ever young." We are also for ever aged and decrepit, on our deathbeds, in the dentist's chair, at Thanksgivings with our in-laws, and reading these words.

But where is all the data from all these eternal universes stored?

Still, it seems to me that the fact that we have particles that take billions of light years to get to us and yet from their perspective got here in zero time over zero distance is enough to at least get one's attention.

It seems to me, that as anything that travels at light speed is effectively outside of time, then light would be able to move freely from one universe to the next under Barbour's scenario.