These are excerpts and elaborations from my book "The Nature of Consciousness"
The Immanent
Manyverse Because of the
apparent approximation of any quantum description of a phenomenon, the Israeli
physicist David Deutsch also thinks that our universe cannot possibly
constitute the whole of reality, that it has to be part of a
"multiverse" of parallel universes.
But Deutsch's multiverse is
not a mere collection of parallel universes, with a single flow of time. He
highlights the contradiction in assuming an external, superior time in which
all spacetimes flow. This would still be a classical view of the world. Deutsch's manyverse is instead a collection
of moments. There is no such thing as
the "flow of time". Each "moment" is a universe of the
manyverse. Each moment exists forever, it does not flow from a previous moment
to a following one. Time does not flow
because time is simply a collection of universes. We exist in multiple versions, in universes called
"moments". A key concept is
"fungibility": it means that a set of objects can be considered as a
set of identical objects. For example, if I lend you one dollar and a few days
later you give me back one dollar, we assume that the state of the world is the
same as it was before the borrowing even though the dollar bill that you return
to me is not the one that I gave you. However, if I lend you a book and you
return me a different book, I would be pretty upset: not all books are alike
the way all dollar bills are alike. Photons are fungible: you can't tell one
from the other. The atoms of lasers are fungible: they are all the same thing.
It turns out that fungible objects can deviate from each other and become
different entities... in different universes of the multiverse. And that is the
origin of the apparent randomness that an individual in one universe observes.
If one views a particle as a multiversal object, randomness and uncertainty
disappear: a particle has multiple positions and multiple speeds in multiple
universes. The wave associated with a particle is not due to the duality of
particles and waves: a particle is distributed across many universes, and
therefore it "is" a wave in the multiverse. Each version of
us is indirectly aware of the others because the various universes are linked
together by the same physical laws, and causality provides a convenient
ordering. But causality is not deterministic in the classical way: it is more
like predicting than like causing. If we analyze the pieces of a jigsaw puzzle,
we can predict where some of the missing pieces fall. But it would be
misleading to say that our analysis of the puzzle "caused" those
pieces to be where they are, although it is true that their position is
"determined" by the other pieces being where they are. Furthermore,
Deutsch claims that Quantum Theory is not enough to
understand reality. He does not adhere to the reductionist stance which says
that to understand a system is to understand its parts and to have a theory of
that system is to have a set of predictions of its future behavior. Deutsch
thinks that the predictions are merely the tools to verify if the theory is
correct, but what really matters is the "explanation" that the theory
provides. Scientific knowledge consists of explanations, not of facts or of
predictions of facts. And, contrary to the dominant "reductionist"
approach, an explanation that reduces large-scale events to the movement of the
smallest possible constituents of matter is not an explanation. As he puts it,
why is a specific atom of copper on the nose of the statue of Churchill? Not
because the dynamic equations of the universe predict this and that, and not
because of the story of that particle, but because Churchill was a famous
person, and famous people are rewarded with statues, and statues are built of
bronze, and bronze is made of copper. Scientists who
adhere to the reductionist stance believe that the rules governing elementary
particles (the base of the reductionist hierarchy) explain everything but they
do not provide the kind of answer that we would call "explanation". So we need four
strands of science to understand reality: a theory of matter (quantum theory),
a theory of evolution, a theory of knowledge (epistemology), and a theory of
computation. The combined theory provides the "explanations" that
Deutsch is interested in. Back to the beginning of the chapter "The New Physics" | Back to the index of all chapters |