clifford_a-_pickover_surfing_through_hyperspacebookfi-org

notes 219
4. Unfortunately, there are so many different ways to create universes by compactifying
the six dimensions that string theory is difficult to relate to the real universe. In
1995, researchers suggested that if string theory takes into account the quantum effects
of charged mini black holes, the thousands of 4-D solutions may collapse to only one.
Tiny black holes, with no more mass than an elementary particle, and strings may be
two descriptions of the same object. Thanks to the theory of mini black holes, physicists
now hope to mathematically follow the evolution of the universe and select one particular
Calabi-Yau compactification—a first step to a testable "theory of everything."
Some trivia: Gabriele Veneziano, in the late 1960s, worked on string theories. However,
interest in his patticular version of the theory faded when other physicists showed
they would only work in twenty-six dimensions. Also, some researchers believe that all
known elementary particles have unseen symmetric twins called sparticles.
5. What we've learned in the 20th century is that the great ideas in physics have
geometric foundations. —Edward Witten, Scientific American
6. Just like the early years of Einstein's theory of relativity, string theory is simply a
set of clever equations waiting for experimental verification. Unfottunately, it would
take an atom smasher thousands of times as powerful as any on Earth to test the current
version of string theory directly. It is hoped that, humans will refine the theoty to
the point where it can be tested in real-world experiments. With Edward Witten
directing his attention to string theory, the world hopes that he and his colleagues can
crack the philosophical mystery that's dodged science ever since the ancient Greeks:
What is the ultimate natute of the universe? What is the loom on which God weaves?
Whatever that loom is, it has created a structurally rich universe. Most astronomers
today believe that the universe is between eight and twenty-five billion years old, and
has been expanding outward ever since. The universe seems to have a fractal nature
with galaxies hanging together in clusters. These clustets form larger clusters (clusters
of clusters). "Superclusters" are clusters of these clusters of clusters. In recent years,
there have been other baffling theories and discoveries. Here are just a few:
• In our universe a Great Wall exists consisting of a huge concentration of galaxies
stretching across 500 million light-years of space.
• In our universe a Great Attractor exists, a mysterious mass pulling much of the
local universe toward the constellations Hydra and Centaurus.
• There are Great Voids in our universe. These are regions of space where few
galaxies can be found.
• Inflation theory continues to be important in describing the evolution of our universe.
Inflation theory suggests that the universe expanded like a drunken balloon-blower's
balloon while the universe was in its first second of life.
• The existence of dark matter also continues to be hypothesized. Dark matter may
consist of subatomic particles that may account for most of the universe's mass.
We don't know what dark matter is composed of, but theories include: neutrinos