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PHYSICS OF THE IMPOSSIBLE
tween universes, but the other galaxy would be invisible to us because
light moves underneath the galaxy. In this way, the galaxy would have
gravity but would be invisible, which fits the description of dark matter. (Yet another possibility is that dark matter might consist of the next
vibration of the superstring. Everything we see around us, such as
atoms and light, is nothing but the lowest vibration of the superstring.
Dark matter might be the next higher set of vibrations.)
To be sure, most of these parallel universes are probably dead
ones, consisting of a formless gas of subatomic particles, such as electrons and neutrinos. In these universes the proton might be unstable,
so all matter as we know it would slowly decay and dissolve. Complex
matter, consisting of atoms and molecules, probably would not be possible in many of these universes.
Other parallel universes might be just the opposite, with complex
forms of matter far beyond anything we can conceive of. Instead of just
one type of atom consisting of protons, neutrons, and electrons, they
might have a dazzling array of other types of stable matter.
These membrane universes might also collide, creating cosmic
fireworks. Some physicists at Princeton believe that perhaps our universe started out as two gigantic membranes that collided 13.7 billion
years ago. The shock waves from that cataclysmic collision created our
universe, they believe. Remarkably, when the experimental consequences of this strange idea are explored they apparently match the results from the WMAP satellite currently orbiting the Earth. (This is
called the "Big Splat" theory.)
The theory of the multiverse has one fact in its favor. When we analyze the constants of nature, we find that they are "tuned" very precisely to allow for life. If we increase the strength of the nuclear force,
then the stars burn out too quickly to give rise to life. If we decrease the
strength of the nuclear force, then stars never ignite at all and life cannot exist. If we increase the force of gravity, then our universe dies
quickly in a Big Crunch. If we decrease the strength of gravity, then the
universe expands rapidly into a Big Freeze. In fact, there are scores of
"accidents" involving the constants of nature that allow for life. Apparently, our universe lives in a "Goldilocks zone" of many parameters,
PHYSICS OF THE IMPOSSIBLE
tween universes, but the other galaxy would be invisible to us because
light moves underneath the galaxy. In this way, the galaxy would have
gravity but would be invisible, which fits the description of dark matter. (Yet another possibility is that dark matter might consist of the next
vibration of the superstring. Everything we see around us, such as
atoms and light, is nothing but the lowest vibration of the superstring.
Dark matter might be the next higher set of vibrations.)
To be sure, most of these parallel universes are probably dead
ones, consisting of a formless gas of subatomic particles, such as electrons and neutrinos. In these universes the proton might be unstable,
so all matter as we know it would slowly decay and dissolve. Complex
matter, consisting of atoms and molecules, probably would not be possible in many of these universes.
Other parallel universes might be just the opposite, with complex
forms of matter far beyond anything we can conceive of. Instead of just
one type of atom consisting of protons, neutrons, and electrons, they
might have a dazzling array of other types of stable matter.
These membrane universes might also collide, creating cosmic
fireworks. Some physicists at Princeton believe that perhaps our universe started out as two gigantic membranes that collided 13.7 billion
years ago. The shock waves from that cataclysmic collision created our
universe, they believe. Remarkably, when the experimental consequences of this strange idea are explored they apparently match the results from the WMAP satellite currently orbiting the Earth. (This is
called the "Big Splat" theory.)
The theory of the multiverse has one fact in its favor. When we analyze the constants of nature, we find that they are "tuned" very precisely to allow for life. If we increase the strength of the nuclear force,
then the stars burn out too quickly to give rise to life. If we decrease the
strength of the nuclear force, then stars never ignite at all and life cannot exist. If we increase the force of gravity, then our universe dies
quickly in a Big Crunch. If we decrease the strength of gravity, then the
universe expands rapidly into a Big Freeze. In fact, there are scores of
"accidents" involving the constants of nature that allow for life. Apparently, our universe lives in a "Goldilocks zone" of many parameters,