By Michael Shermer
Why is there something rather that nothing? This is one of those
profound questions that is easy to ask but difficult to answer. For
millennia humans simply said, “God did it”: a creator existed before the
universe and brought it into existence out of nothing. But this just
begs the question of what created God - and if God does not need a
creator, logic dictates that neither does the universe. Science deals
with natural (not supernatural) causes and, as such, has several ways of
exploring where the “something” came from.
Multiple universes. There are many multiverse
hypotheses predicted from mathematics and physics that show how our
universe may have been born from another universe. For example, our
universe may be just one of many bubble universes with varying laws of
nature. Those universes with laws similar to ours will produce stars,
some of which collapse into black holes and singularities that give
birth to new universes - in a manner similar to the singularity that
physicists believe gave rise to the big bang.
M-theory. In his and Leonard Mlodinow’s 2010 book, The Grand Design,
Stephen Hawking embraces “M-theory” (an extension of string theory that
includes 11 dimensions) as “the only candidate for a complete theory of
the universe. If it is finite - and this has yet to be proved - it will be a
model of a universe that creates itself.”
Quantum foam creation. The “nothing” of the vacuum of
space actually consists of subatomic spacetime turbulence at extremely
small distances measurable at the Planck scale - the length at which the
structure of spacetime is dominated by quantum gravity. At this scale,
the Heisenberg uncertainty principle allows energy to briefly decay into
particles and antiparticles, thereby producing “something” from
“nothing.”
Nothing is unstable. In his new book, A Universe from Nothing,
cosmologist Lawrence M. Krauss attempts to link quantum physics to
Einstein’s general theory of relativity to explain the origin of a
universe from nothing: “In quantum gravity, universes can, and indeed
always will, spontaneously appear from nothing. Such universes need not
be empty, but can have matter and radiation in them, as long as the
total energy, including the negative energy associated with gravity
[balancing the positive energy of matter], is zero.” Furthermore, “for
the closed universes that might be created through such mechanisms to
last for longer than infinitesimal times, something like inflation is
necessary.”
Observations show that the universe is in fact flat (there
is just enough matter to slow its expansion but not to halt it), has
zero total energy and underwent rapid inflation, or expansion, soon
after the big bang, as described by inflationary cosmology. Krauss
concludes: “Quantum gravity not only appears to allow universes to be
created from nothing - meaning absence of space and time - it may require
them. ‘Nothing’ - in this case no space, no time, no anything! - is
unstable.”
The other hypotheses are also testable. The idea that new universes can
emerge from collapsing black holes may be illuminated through
additional knowledge about the properties of black holes, which are
being studied now. Other bubble universes might be detected in the
subtle temperature variations of the cosmic microwave background
radiation left over from the big bang of our own universe. NASA’s
Wilkinson Microwave Anisotropy Probe (WMAP) spacecraft is collecting
data on this radiation. Additionally, the Laser Interferometer
Gravitational Wave Observatory (LIGO) is designed to detect
exceptionally faint gravitational waves. If there are other universes,
perhaps ripples in gravitational waves will signal their presence. Maybe
gravity is such a relatively weak force (compared with electromagnetism
and the nuclear forces) because some of it “leaks” out to other
universes.
Even if God is hypothesized as the creator of the laws of nature that
caused the universe (or multiverse) to pop into existence out of
nothing - if such laws are deterministic - then God had no choice in the
creation of the universe and thus was not needed. In any case, why turn
to the supernatural when our understanding of the natural is still in
its incipient stages? We would be wise to heed this skeptical principle:
before you say something is out of this world, first make sure that it
is not in this world.
About the author:
Mr. Shermer is also the founding publisher and a frequent contributor to Skeptic magazine.
Image source here