Andrew
Hamilton at the University of Colorado has some cool animated
visualization aids that might be helpful to you:
Approaching
the black hole
Orbiting
the black hole
Diving
into the black hole
Falling
to the center of the black hole
A
schematic diagram of the black hole's structure
Gravitational
slowing of light
A
hypothetical wormhole
How
such a wormhole would swiftly collapse
Falling
into the wormhole
Hypothetical
black hole radiation
The idea of the black hole first emerged as a solution to
Einstein's equations describing the gravitational field. It
was an exotic concept at first, but we now know that black
holes are ubiquitous in the universe. The astronomers think
that every major galaxy, including our own, has a stupendously
enormous black hole at its center. Is it an accident that
spiral galaxies resemble water going down a drain, or a twist
in a balloon animal? I don't think so, and the younger and
wilder-eyed theoretical physicists don't think so either.
Another possible solution for Einstein's equations is the
white hole. Specifically, a white hole is the time reversal
of a black hole. While a black hole acts as a point mass that
attracts and absorbs any nearby matter, a white hole acts
as a point mass that repels or (possibly) even generates matter.
White holes are part of the solution to the Einstein equations
that describe wormholes, like the one in
Star Trek: Deep Space Nine. One end of this hypothetical
wormhole is a black hole, swallowing up matter, and the other
is a white hole, spitting the matter back out. Sadly for us
Trekkies, Einstein's equations also say that wormholes are
unstable, disconnecting instantaneously as soon as they form.
So there's not much hope for space travel that way.
No one has ever seen a white hole out in space. But absence
of evidence is not evidence of absence. Some physicists speculate
that the entire universe might be a higher-dimensional white
hole. The idea is that the big bang
was actually the collapse of a black hole out there in the
higher-dimensional spacetime bulk.
The collapse of this enormous hyperstar
forced a white hole into being in a new region of three-dimensional
space. The white hole's explosive birth then unfolded according
to the standard big bang theory, and fourteen billion years
or so later, here we all are. The math also suggests the possibility
that a new universe is created at the core of every
black hole. The new universe expands into the bulk outside
our three-dimensional region of space, touching ours but inaccessible,
like links of a sausage (thanks Douglas
Adams for this analogy.) As matter and energy fall into
the black hole in our universe, it emerges in the newly expanding
baby universe. Lee
Smolin thinks that the
evolution of the multiverse might resemble Darwinian natural
selection. If universes are generated by black holes,
then universes with more black holes will tend to produce
more universes.
If the universe is indeed a white hole, it could explain
the puzzling fact that space is expanding, at a steadily accelerating
rate. There's a mysterious and invisible field of energy pervading
the universe that acts like antigravity, pushing everything
away from everything else. The physicists have nicknamed this
hypothetical field 'dark energy' - it's 'dark' because it
doesn't interact electromagnetically or via the known nuclear
forces, which makes it hard for us to detect directly. It's
distinctly possible that this dark energy is something exotic
and hyperspatial that's falling into our universe through
our parent black hole.
It's a good time to be a spiritual materialist right now.
There's a lot of new information coming in from the giant
space-borne satellites and computer
simulations. I'm staying eagerly tuned.
© ethan hein 2007 | back
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