problem facing astrophysicists is that they have
to explain why the universe appears to be
expanding at an ever increasing rate. The most
popular explanation is that some sort of force
is pushing the accelerating the universe's
expansion. That force is generally attributed to
a mysterious dark energy.
Although dark energy may seem a
bit contrived to some, the Oxford theorists are
proposing an even more outrageous alternative.
They point out that it's possible that we simply
live in a very special place in the universe -
specifically, we're in a huge void where the
density of matter is particularly low. The
suggestion flies in the face of the Copernican
Principle, which is one of the most useful and
widely held tenets in physics.
Copernicus was among the first
scientists to argue that we're not in a special
place in the universe, and that any theory that
suggests that we're special is most likely
wrong. The principle led directly to the
replacement of the Earth-centered concept of the
solar system with the more elegant sun-centered
Dark energy may seem like a stretch, but it's
consistent with the venerable Copernican
Principle. The proposal that we live in a
special place in the universe, on the other
hand, is likely to shock many scientists. The
maverick physicists at Oxford conclude their
paper by pointing out that forthcoming tests of
the Copernican principle should help us sort out
the mystery in the next few years.