“This might suggest
that the so-called imaginary time is really the real time, and that what we
call real time, and that what we call real time is just a figment of our
imaginations. In real time, the universe
has a beginning and an end at singularities that form a boundary to space-time
and at which the laws of science break down.
But in imaginary time is really more basic, and what we call real is
just an idea that we invent to help us describe what we think the universe is
like.”
End of Chapter 8
“The idea that space
and time may form a closed surface without boundary also has profound
implications for the role of God in the affairs of the universe. With the success of scientific theories in
describing events, most people have come to believe that God allows the
universe to evolve according to a set of laws and does not intervene in the
universe to break these laws. However,
the laws do not tell us what the universe should have looked like when it
started—it would still be up to God to wind up the clockwork and choose how to
start it off. So long as the universe
had a beginning we could suppose it had a creator. But if the universe is really completely
self-contained, having no boundary or edge, it would have neither beginning nor
end: it would simply be. What place then
for a creator?”
In Chapter 9
“To return to the arrow
of time, there remains the question: why do we observe that the thermodynamic
and cosmological arrows point in the same direction? Or in other words, why does disorder increase
in the same direction of time as that in which the universe expands? If one believes that the universe will expand
and then contract again, as the no boundary proposal seems to imply, this
becomes a question of why we should be in the expanding phase rather than the
contracting phase.
One can answer this on
the basis of the weak anthropic principle.
Conditions in the contracting phase would not be suitable for the
existence of intelligent beings who could ask the question: why is disorder
increasing in the same direction of time as that in which the universe is expanding?”
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