FORCE FIELDS 7
sive; is extremely weak, relatively speaking; and works over
enormous, astronomical distances. In other words, it is almost the opposite of the flat, thin, impenetrable barrier that
one reads about in science fiction or one sees in science fiction movies. For example, it takes the entire planet Earth to
attract a feather to the floor, but we can counteract Earth's
gravity by lifting the feather with a finger. The action of our
finger can counteract the gravity of an entire planet that
weighs over six trillion trillion kilograms.
2. Electromagnetism (EM), the force that lights up our
cities. Lasers, radio, TV, modern electronics, computers, the
Internet, electricity, magnetism-all are consequences of the
electromagnetic force. It is perhaps the most useful force
ever harnessed by humans. Unlike gravity, it can be both attractive and repulsive. However, there are several reasons
that it is unsuitable as a force field. First, it can be easily
neutralized. Plastics and other insulators, for example, can
easily penetrate a powerful electric or magnetic field. A
piece of plastic thrown in a magnetic field would pass right
through. Second, electromagnetism acts over large distances and cannot easily be focused onto a plane. The laws
of the EM force are described by James Clerk Maxwell's
equations, and these equations do not seem to admit force
fields as solutions.
3 & 4. The weak and strong nuclear forces. The weak
force is the force of radioactive decay. It is the force that
heats up the center of the Earth, which is radioactive. It is
the force behind volcanoes, earthquakes, and continental
drift. The strong force holds the nucleus of the atom together. The energy of the sun and the stars originates from
the nuclear force, which is responsible for lighting up the
universe. The problem is that the nuclear force is a shortrange force, acting mainly over the distance of a nucleus.
Because it is so bound to the properties of nuclei, it is extremely hard to manipulate. At present the only ways we
sive; is extremely weak, relatively speaking; and works over
enormous, astronomical distances. In other words, it is almost the opposite of the flat, thin, impenetrable barrier that
one reads about in science fiction or one sees in science fiction movies. For example, it takes the entire planet Earth to
attract a feather to the floor, but we can counteract Earth's
gravity by lifting the feather with a finger. The action of our
finger can counteract the gravity of an entire planet that
weighs over six trillion trillion kilograms.
2. Electromagnetism (EM), the force that lights up our
cities. Lasers, radio, TV, modern electronics, computers, the
Internet, electricity, magnetism-all are consequences of the
electromagnetic force. It is perhaps the most useful force
ever harnessed by humans. Unlike gravity, it can be both attractive and repulsive. However, there are several reasons
that it is unsuitable as a force field. First, it can be easily
neutralized. Plastics and other insulators, for example, can
easily penetrate a powerful electric or magnetic field. A
piece of plastic thrown in a magnetic field would pass right
through. Second, electromagnetism acts over large distances and cannot easily be focused onto a plane. The laws
of the EM force are described by James Clerk Maxwell's
equations, and these equations do not seem to admit force
fields as solutions.
3 & 4. The weak and strong nuclear forces. The weak
force is the force of radioactive decay. It is the force that
heats up the center of the Earth, which is radioactive. It is
the force behind volcanoes, earthquakes, and continental
drift. The strong force holds the nucleus of the atom together. The energy of the sun and the stars originates from
the nuclear force, which is responsible for lighting up the
universe. The problem is that the nuclear force is a shortrange force, acting mainly over the distance of a nucleus.
Because it is so bound to the properties of nuclei, it is extremely hard to manipulate. At present the only ways we