Thursday, July 9, 2009

(2) Cosmic Contour

As a physicist I was cognizant of the "Big Bang" originally labeled
by antagonist Fred Hoyle. He actually didn't accept the Big Bang
theory and used the term in a derisive way. However, in 1964,
Arno Penzias and Robert Wilson accidentally discovered the
cosmic background radiation of the Big Bang At the time they
were in charge of a new Bell Laboratories microwave receiver,
and this receiver kept picking-up signals--from everywhere!
They thought there were kinks in the receiver, no, then they
figured it must be some sort of outside interference, like birds
defecating on the receiver, again no. So it had to be cosmic
radiation residue from the Big Bang!

At the same time, in nearby Princeton University, scientists
were intent looking for this cosmic background radiation. Word
got around, and they knew that Wilson and Penzias' microwave
receiver had done it. And 25 years later, in 1989, the Cosmic
Background Explorer satellite (COBE) was launched--and its
findings were consistent regarding the cosmic microwave
background of the Big Bang.

As to what this means is yet another story. The theoretics for the
Big Bang were already in place, years before its background
radiation was picked-up by Penzias and Wilson. In 1927
Georges Lemaitre, a physicist and a Roman Catholic priest
from Belgium, had presented his theory of what was to become
known as the Big Bang. He believed that the universe began as
a single point, a form no larger than a cell, and it "exploded."
In a few seconds the universe began to expand into what is now
considered a dense, hot "primordial soup." Later elements evolved
that allowed for the formation of galaxies, millions upon millions,
with billions of suns and presumably solar systems. Hence the
possibility of finding planets, eventually, that might sustain Life.
We have only begun the search, and someday we might be
surprised.

Using special astrophysical technology, the latest estimate is
that our universe is some 13.7 billion years old. Scientists
believe that it's an expanding universe, with the galaxies moving
farther away from one another. And here it begins to get strange.
Astronomers today figure that our present universe is composed
of Dark Energy (74%), Dark Matter (22%), and Normal Matter (4%)--
and out of that 4%, most is gas and only a minute percentage
accounts for stars and their systems.

And whatever might be Dark Matter and Dark Energy? They are
hypothetical terms that cosmologists use. They believe that
Dark Matter can be inferred by its gravitational effects on normal
matter. As for Dark Energy, it is believed that it permeates all
space and is behind the increasing expansion rate of the universe,

As for the surface of the universe, geometrists are continuously
challenged. The geometry of the universe considers two
possibilities, either the universe is curved or it is flat. And recently,
NASA announced that their WMAP (Wilkinson Microwave
Anisotropy Probe) spacecraft has pretty much confirmed that
our universe is flat--with only a 2% margin of error.

So whatever does this mean? Well a flat universe involves
accelerative expansion. As cosmologists put, absent
Dark Energy a flat universe will expand forever with an
eventual fixed rate. But with the presence of Dark Energy--
all 74% of it--the acceleration of the universe slows down,
but in time eventually increases.

Alas, an uncomfortable topic--the ultimate fate of the universe!
The candidates have been as follows: Heat Death, the Big
Freeze, the Big Crunch, and more recently the Big Rip. If the
WMAP is definitely correct about ours being a flat universe, and
the measurement of Dark Energy is on the mark, well than the
leading candidate is the Big Rip. If so, all normal matter will
disintegrate into unbound elementary particles as the rest of
the universe continues to expand infinitely. But cosmologists
tell us that sad event is a long, long way off. Still it's not a
comfortable thought.

Overall, however, our fledgling empirical observations of our
universe are leading into a Mystery. If we continue to increase
our knowledge, who is to say what Wonder we might discover.
But for now it's just strangely weird.

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