Sidebar: Cosmic Inflation as described by its
creator, Alan Guth
Inflation is a well documented theory. So again, rather than
re-invent the wheel and create yet another description, I present
instead the description of how inflation works as told by its creator
Alan Guth when he presented it on Morgan Freeman's Through the Wormhole,
Episode What Happened before the Beginning1. A transcript follows below
the video. Watch for the irony at the end where Guth, in his
attempt to show how an undirected, unguided force brings "order to the
universe" by showing an intelligent agent directing the process by
laying down (in paint) exactly how the expansion should unfold.
Transcript:
Morgan Freeman (Narrator):
Forty years after two radio astronomers first heard a faint whisper
from our own cosmic birth, David Spergel now has his baby picture of the
universe. Despite the vibrant colors visible in the WMAP image, it only
describes a miniscule variation in temperature across the universe."
David Spergel:
"We look at the WMAP map, what we're seeing are tiny variations in the
temperature of the universe from place to place. Variations that are one
part in 10,000; one part in 100,000. So I think that the universe we
look at from the WMAP satellite as not being chaotic, being very
ordered, homogeneous and smooth."
Freeman:
"But if time and space started in a cataclysm explosion of energy,
wouldn't the universe be uneven and messy in all directions?"
Alan Guth:
"Not exactly. So I can't start this from "not exactly can I?" (laughs)
Freeman:
"For Dr. Alan Guth, what happened during this early moment in time was
an intriguing mystery that had to be solved. Figuring this out became
his life's work."
Guth:
"There had been in cosmology a serious problem in understanding the
uniformity of the universe. [The Universe] has the same intensity every
direction that we go. To 1 part in 100,000. And that means that the big
bang was unbelievably uniform. That's hard to understand because
conventional explosions just don't behave that way.
"We set up a balloon that's going to be dropped from very high up there
on the frame. The balloon is filled with paint, and we'll get to see
what kind of a splat a typical explosion makes.
"So this is what a typical explosion might look like. And as you can see
it's anything but uniform. Splotch here, splotch there, white spots in
between. The early universe was nothing like what's on the canvas here."
Freeman:
"Alan needed something that would immediately smooth out all the hot
dense plasma that had just come into existence. "
Guth:
"I can across this idea of inflation. The idea that gravity under some
circumstances acts repulsively and produced a gigantic acceleration in
the expansion of the universe. This could have happened in the very
early universe.
"The key idea behind inflation is the possibility that at least a small
patch of the early universe became a kind of repulsive gravity material.
And all you need is a tiny patch of that and the big bang starts with
this repulsive gravity effect."
Freeman:
"Cosmic inflation takes place right after a pop from nothing into
something. About one trillion trillion trillionth of a second after it,
the force field takes all the highly compressed space created in that
singular moment, which is still almost infinitely small, and drives it
out. A tiny fraction of a second later, the universe has
doubled in size 100,000 times.
A different kind of painting illustrates this idea."
Guth:
"We're going to paint in time lapse photography, a growing sphere.
Instead of getting the splotch, we had when we just dropped the balloon,
here we should see a very smooth growth of the early universe"
Freeman:
"With this smooth, and orderly expansion, our universe was formed."
Guth:
"This idea of inflation has now essentially become the standard version
of cosmology and makes a number of predictions which have been
confirmed. So it agrees very well with what we see." [On screen: time
lapse of the painted growing dot that represents an orderly expansion of
the universe.]
Freeman:
"With the addition of inflation, the big bang became a cohesive three
act play.
Act one - a singularity pops into existence out of nowhere and no-when
and containing in one single dot all the energy that will ever be in our
universe.
Act two - Inflation suddenly takes hold. An unimaginably rapid expansion
of space smoothes the spreading out of that energy bringing order to the
universe. It's now a massive soup of evenly expanding plasma.
Act three - the universe cools. Matter begins to clump together under
the force of gravity. Eventually forming stars, galaxies and planets.
For most cosmologists, this three act play is the best explanation of
what happened at the beginning of the universe. But not for every body."