8
PHYSICS OF THE IMPOSSIBLE
have of manipulating this force are to blow subatomic particles apart in atom smashers or to detonate atomic bombs.
Although the force fields used in science fiction may not conform
to the known laws of physics, there are still loopholes that might make
the creation of such a force field possible. First, there may be a fifth
force, still unseen in the laboratory. Such a force might, for example,
work over a distance of only a few inches to feet, rather than over astronomical distances. (Initial attempts to measure the presence of such
a fifth force, however, have yielded negative results.)
Second, it may be possible to use a plasma to mimic some of the
properties of a force field. A plasma is the "fourth state of matter."
Solids, liquids, and gases make up the three familiar states of matter,
but the most common form of matter in the universe is plasma, a gas
of ionized atoms. Because the atoms of a plasma are ripped apart, with
electrons torn off the atom, the atoms are electrically charged and can
be easily manipulated by electric and magnetic fields.
Plasmas are the most plentiful form of visible matter in the universe, making up the sun, the stars, and interstellar gas. Plasmas are
not familiar to us because they are only rarely found on the Earth, but
we can see them in the form of lightning bolts, the sun, and the interior of your plasma TV.
PLASMA
WINDOWS
As noted above, if a gas is heated to a high enough temperature,
thereby creating a plasma, it can be molded and shaped by magnetic
and electrical fields. It can, for example, be shaped in the form of a
sheet or window. Moreover, this "plasma window" can be used to separate a vacuum from ordinary air. In principle, one might be able to
prevent the air within a spaceship from leaking out into space, thereby
creating a convenient, transparent interface between outer space and
the spaceship.
In the Star Trek TV series, such a force field is used to separate the
PHYSICS OF THE IMPOSSIBLE
have of manipulating this force are to blow subatomic particles apart in atom smashers or to detonate atomic bombs.
Although the force fields used in science fiction may not conform
to the known laws of physics, there are still loopholes that might make
the creation of such a force field possible. First, there may be a fifth
force, still unseen in the laboratory. Such a force might, for example,
work over a distance of only a few inches to feet, rather than over astronomical distances. (Initial attempts to measure the presence of such
a fifth force, however, have yielded negative results.)
Second, it may be possible to use a plasma to mimic some of the
properties of a force field. A plasma is the "fourth state of matter."
Solids, liquids, and gases make up the three familiar states of matter,
but the most common form of matter in the universe is plasma, a gas
of ionized atoms. Because the atoms of a plasma are ripped apart, with
electrons torn off the atom, the atoms are electrically charged and can
be easily manipulated by electric and magnetic fields.
Plasmas are the most plentiful form of visible matter in the universe, making up the sun, the stars, and interstellar gas. Plasmas are
not familiar to us because they are only rarely found on the Earth, but
we can see them in the form of lightning bolts, the sun, and the interior of your plasma TV.
PLASMA
WINDOWS
As noted above, if a gas is heated to a high enough temperature,
thereby creating a plasma, it can be molded and shaped by magnetic
and electrical fields. It can, for example, be shaped in the form of a
sheet or window. Moreover, this "plasma window" can be used to separate a vacuum from ordinary air. In principle, one might be able to
prevent the air within a spaceship from leaking out into space, thereby
creating a convenient, transparent interface between outer space and
the spaceship.
In the Star Trek TV series, such a force field is used to separate the