PARALLEL UNIVERSES 237
proving the existence of these higher dimensions. Perhaps the simplest
way to prove the existence of higher dimensions would be to find deviations from Newton's law of gravity. In high school we learn that the
gravity of the Earth diminishes as we go into outer space. More precisely, gravity diminishes with the square of the distance of separation.
But this is only because we live in a three-dimensional world. (Think
of a sphere surrounding the Earth. The gravity of the Earth spreads out
evenly across the surface of the sphere, so the larger the sphere, the
weaker the gravity. But since the surface of the sphere grows as the
square of its radius, the strength of gravity, spread out over the surface
of the sphere, must diminish as the square of the radius.)
But if the universe had four spatial dimensions, then gravity
should diminish as the cube of the distance of separation. If the universe had n spatial dimensions, then gravity should diminish as the n -
l-\h power. Newton's famous inverse-square law has been tested with
great accuracy over astronomical distances; that is why we can send
space probes soaring past the rings of Saturn with breathtaking accuracy. But until recently Newton's inverse-square law had never been
tested at small distances in the laboratory.
The first experiment to test the inverse-square law at small distances was performed at the University of Colorado in 2003 with negative results. Apparently there is no parallel universe, at least not in
Colorado. But this negative result has only whetted the appetite of
other physicists, who hope to duplicate this experiment with even
greater accuracy.
Furthermore, the Large Hadron Collider, which will become operational in 2008 outside Geneva, Switzerland, will be looking for a new
type of particle called the "sparticle," or superparticle, which is a
higher vibration of the superstring (everything you see around you is
but the lowest vibration of the superstring). If sparticles are found by
the LHC, it could signal a revolution in the way we view the universe.
In this picture of the universe, the Standard Model simply represents
the lowest vibration of the superstring.
Rip Thorne says, "By 2020, physicists will understand the laws of
quantum gravity, which will be found to be a variant of string theory."
proving the existence of these higher dimensions. Perhaps the simplest
way to prove the existence of higher dimensions would be to find deviations from Newton's law of gravity. In high school we learn that the
gravity of the Earth diminishes as we go into outer space. More precisely, gravity diminishes with the square of the distance of separation.
But this is only because we live in a three-dimensional world. (Think
of a sphere surrounding the Earth. The gravity of the Earth spreads out
evenly across the surface of the sphere, so the larger the sphere, the
weaker the gravity. But since the surface of the sphere grows as the
square of its radius, the strength of gravity, spread out over the surface
of the sphere, must diminish as the square of the radius.)
But if the universe had four spatial dimensions, then gravity
should diminish as the cube of the distance of separation. If the universe had n spatial dimensions, then gravity should diminish as the n -
l-\h power. Newton's famous inverse-square law has been tested with
great accuracy over astronomical distances; that is why we can send
space probes soaring past the rings of Saturn with breathtaking accuracy. But until recently Newton's inverse-square law had never been
tested at small distances in the laboratory.
The first experiment to test the inverse-square law at small distances was performed at the University of Colorado in 2003 with negative results. Apparently there is no parallel universe, at least not in
Colorado. But this negative result has only whetted the appetite of
other physicists, who hope to duplicate this experiment with even
greater accuracy.
Furthermore, the Large Hadron Collider, which will become operational in 2008 outside Geneva, Switzerland, will be looking for a new
type of particle called the "sparticle," or superparticle, which is a
higher vibration of the superstring (everything you see around you is
but the lowest vibration of the superstring). If sparticles are found by
the LHC, it could signal a revolution in the way we view the universe.
In this picture of the universe, the Standard Model simply represents
the lowest vibration of the superstring.
Rip Thorne says, "By 2020, physicists will understand the laws of
quantum gravity, which will be found to be a variant of string theory."