Hey! You Got Science in my Science Fiction (Essays)

Wormholes and Freeze Rays

We've already talked about the difficulties with the speed of light. This is a serious problem for science fiction writers, not to be taken lightly (heh, get it? lightly? Okay, sorry). The concept of a wormhole or tunnel from one region of spacetime to another is a viable way to get around, as no one travels faster than the speed of light--they just take a shortcut.

Sometimes, however, shortcuts are not what they're cracked up to be.

Back in 1915, Einstein published his theory of general relativity. At the time, very little was understood about the theory, even by Einstein himself. It took one year before Schwarzschild discovered a solution to the Einstein equations--a black hole. Later it was realized that this solution contains a wormhole. Unfortunately, it is impossible to traverse the wormhole without traveling faster than light. Also, dying upon getting close to the black hole/wormhole from tidal forces is another problem. What are tidal forces? Well, you may not be aware that when you are standing, the earth pulls more strongly on your feet than on your head. The difference is very small. Near the horizon of a black hole, however, that difference is large enough to tear you apart.

So what you need is not merely a "wormhole" but a "traversable wormhole."

And how do you make a traversable wormhole? It turns out that you need negative mass-energy density. This is really weird stuff (if it exists at all). Note that this is *not* antimatter. Antimatter would have opposite charge. If matter and antimatter collide, they release their masses as energy. If mass and negative mass were to collide, they would silently cease to be. Poof. One plus negative one equals zero.

Imagine a rock with negative mass-energy sitting next to a rock with positive mass-energy.  The negative mass would repel the positive mass, but the positive mass would attract the negative mass. The net result would be that they would chase each other, endlessly accelerating. How could that be? Wouldn't that violate some principle of momentum or energy conservation? The answer is, no. The net energy and momentum of the positive and negative rocks would always cancel to zero.

This two rock starship would definitely be a cool design, don't you think?

In any event, to build a spacetime with traversable wormholes, you need lots of negative mass-energy to spread around in order to quell tidal forces and prevent event horizons from forming. In my book, "Warriors of the Hollow World," I use the term "phantom energy" describe this miraculous stuff.

Does it exist? Maybe. "Dark Energy" is used to explain the repulsive force that causes the universe to accelerate apart. It is modeled as negative mass-energy, but can we can we take this seriously? What does it look like? What if we could produce negative energy photons?

If these hypothetical beasts existed, you could shine them on atoms and cause electrons to drop into a lower state. If that doesn't sound exciting to you, consider this--it means that a laser firing negative energy photons would be a freeze ray. As if creating a freeze ray wasn't "cool" enough, a consequence of generating a negative energy beam would be a postive energy beam (energy has to balance). Thus, for no energy input, you get two beams, one with positive energy (a laser), and one with negative (a freeze ray). Both of these would be handy weapons.

It gets better, though. If you have a starship and fire the freeze ray ahead of you and the laser behind you, you get photonic thrust from both directions! Firing the freeze ray forward pulls your ship along while the laser pushes it. These beams could be arbitrarily strong, since generating the two of them costs zero energy.

Someday, I want to write a story about this bizarre starship.

"FIRE AND ICE" BY ROBERT FROSTSome say the world will end in fire,Some say in ice.From what Iʼve tasted of desireI hold with those who favor fire.But if it had to perish twice,I think I know enough of hateTo say that for destruction iceIs also greatAnd would suffice.