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PHVSICS OF THE IMPOSSIBLE
that particular space-time. (This means that if you are given a bizarre
collection of waves on the surface of a pond, you can work backward
and calculate the distribution of rocks necessary to produce these
waves). This was, in fact, the way in which Alcubierre derived his
equations. He began with a space-time consistent with going faster
than light, and then he worked backward and calculated the energy
necessary to produce it.
WORMHOLES AND BLACK HOLES
Besides stretching space, the second possible way to break the light
barrier is by ripping space, via wormholes, passageways that connect
two universes. In fiction, the first mention of a wormhole came from
Oxford mathematician Charles Dodgson, who wrote Through the
Looking Glass under the pen name Lewis Carroll. The Looking Glass
of Alice is the wormhole, connecting the countryside of Oxford with
the magical world of Wonderland. By placing her hand through the
Looking Glass, Alice can be transported instantly from one universe to
the next. Mathematicians call these "multiply connected spaces."
The concept of wormholes in physics dates back to 1916, one year
after Einstein published his epic general theory of relativity. Physicist
Karl Schwarzschild, then serving in the Raiser's army, was able to
solve Einstein's equations exactly for the case of a single pointlike star.
Far from the star, its gravitational field was very similar to that of an
ordinary star, and in fact Einstein used Schwarzschild's solution to calculate the deflection of light around a star. Schwarzschild's solution
had an immediate and profound impact on astronomy, and even today
it is one of the best-known solutions of Einstein's equations. For generations, physicists used the gravitational field around this pointlike
star as an approximation to the field around a real star, which has a finite diameter.
But if you took this pointlike solution seriously, then lurking at the
center of it was a monstrous pointlike object that has shocked and
amazed physicists for almost a century-a black hole. Schwarzschild's
PHVSICS OF THE IMPOSSIBLE
that particular space-time. (This means that if you are given a bizarre
collection of waves on the surface of a pond, you can work backward
and calculate the distribution of rocks necessary to produce these
waves). This was, in fact, the way in which Alcubierre derived his
equations. He began with a space-time consistent with going faster
than light, and then he worked backward and calculated the energy
necessary to produce it.
WORMHOLES AND BLACK HOLES
Besides stretching space, the second possible way to break the light
barrier is by ripping space, via wormholes, passageways that connect
two universes. In fiction, the first mention of a wormhole came from
Oxford mathematician Charles Dodgson, who wrote Through the
Looking Glass under the pen name Lewis Carroll. The Looking Glass
of Alice is the wormhole, connecting the countryside of Oxford with
the magical world of Wonderland. By placing her hand through the
Looking Glass, Alice can be transported instantly from one universe to
the next. Mathematicians call these "multiply connected spaces."
The concept of wormholes in physics dates back to 1916, one year
after Einstein published his epic general theory of relativity. Physicist
Karl Schwarzschild, then serving in the Raiser's army, was able to
solve Einstein's equations exactly for the case of a single pointlike star.
Far from the star, its gravitational field was very similar to that of an
ordinary star, and in fact Einstein used Schwarzschild's solution to calculate the deflection of light around a star. Schwarzschild's solution
had an immediate and profound impact on astronomy, and even today
it is one of the best-known solutions of Einstein's equations. For generations, physicists used the gravitational field around this pointlike
star as an approximation to the field around a real star, which has a finite diameter.
But if you took this pointlike solution seriously, then lurking at the
center of it was a monstrous pointlike object that has shocked and
amazed physicists for almost a century-a black hole. Schwarzschild's