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A CosmicPoker Game In which the physics of inertial dampers and tractor beams paves the way for time travel, warp speed, deflector shields, wormholes, andother spacetime oddities
Chapter One Newton Antes
"No matter where you go, there you are."
—From a plaque on the starship Excelsior, in Star Trek VI: The Undiscovered Country, presumably borrowed from The Adventures of Buckaroo Banzai
You are at the helm of the starship Defiant (NCC-1764), currently in orbit around the planet Iconia, near the Neutral Zone. Your mission: to rendezvous with a nearby supply vessel at the other end of this solar system in order to pick up components to repair faulty transporter primary energizing coils. There is no need to achieve warp speeds; you direct the impulse drive to be set at full power for leisurely half-light-speed travel, which should bring you to your destination in a few hours, giving you time to bring the captain's log up to date. However, as you begin to pull out of orbit, you feel an intense pressure in your chest. Your hands are leaden, and you are glued to your seat. Your mouth is fixed in an evil-looking grimace, your eyes feel like they are about to burst out of their sockets, and the blood flowing through your body refuses to rise to your head. Slowly, you lose consciousness . . . and within minutes you die.
What happened? It is not the first signs of spatial "interphase" drift, which will later overwhelm the ship, or an attack from a previously cloaked Romulan vessel. Rather, you have fallen prey to something far more powerful. The ingenious writers of Star Trek, on whom youdepend, have not yet invented inertial dampers, which they will introduce sometime later in the series. You have been defeated by nothing more exotic than Isaac Newton's laws of motion—the very first things one can forget about high school physics.
OK, I know some trekkers out there are saying to themselves, "How lame! Don't give me Newton. Tell me things I really want to know, like 'How does warp drive work?' or 'What is the flash before going to warp speed—is it like a sonic boom?' or 'What is a dilithium crystal anyway?'" All I can say is that we will get there eventually. Travel in the Star Trek universe involves some of the most exotic concepts in physics. But many different aspects come together before we can really address everyone's most fundamental question about Star Trek: "Is any of this really possible, and if so, how?"
To go where no one has gone before—indeed, before we even get out of Starfleet Headquarters—we first have to confront the same peculiarities that Galileo and Newton did over three hundred years ago. The ultimate motivation will be the truly cosmic question which was at the heart of Gene Roddenberry's vision of Star Trek and which, to me, makes this whole subject worth thinking about: "What does modern science allow us to imagine about our possible future as a civilization?"
Anyone who has ever been in an airplane or a fast car knows the feeling of being pushed back into the seat as the vehicle accelerates from a standstill. This phenomenon works with a vengeance aboard a starship. The fusion reactions in the impulse drive produce huge pressures, which push gases and radiation backward away from the ship at high velocity. It is the backreaction force on the engines—from the escaping gas and radiation—that causes the engines to "recoil" forward. The ship, being anchored to the engines, also recoils forward. At the helm, you are pushed forward too, by the force of the captain's seat on your body. In turn, your body pushes back on the seat.
Now, here's the catch. Just as a hammer driven at high velocity toward your head will produce a force on your skull which can easily be lethal, the captain's seat will kill you if the force it applies to you is too great. Jet pilots and NASA have a name for the force exerted on your body while you undergo high accelerations (as in a plane or during a space launch): G-forces. I can describe these by recourse to my aching back: As I am sitting at my computer terminal busily typing, I feel the ever-present pressure of my office chair on my buttocks—a pressure that I have learned to live with (yet, I might add, that my buttocks are slowly reacting to in a very noncosmetic way). The force on my buttocks results from the pull of gravity, which if given free rein would accelerate me downward into the Earth. What stops me from accelerating—indeed, from moving beyond my seat—is the ground exerting an opposite upward force on my house's concrete and steel frame, which exerts an upward force on the wood floor of my second-floor study, which exerts a force on my chair, which in turn exerts a force on the part of my body in contact with it. If the Earth were twice as massive but had the same diameter, the pressure on my buttocks would be twice as great. The upward forces would have to compensate for the force of gravity by being twice as strong.
The same factors must be taken into account in space travel. If you are in the captain's seat and you issue a command for the ship to accelerate, you must take into account the force with which the seat will push you forward. If you request an acceleration twice as great, the force on you from the seat will be twice as great. The greater the acceleration, the greater the push. The only problem is that nothing can withstand the kind of force needed to accelerate to impulse speed quickly—certainly not your body.
By the way, this same problem crops up in different contexts throughout Star Trek—even on Earth. At the beginning of Star Trek V: The Final Frontier, James Kirk is free-climbing while on vacation in Yosemite when he slips and falls. Spock, who has on his rocket boots, speeds to the rescue, aborting the captain's fall within a foot or two of the ground. Unfortunately, this is a case where the solution can be as bad as the problem. It is the process of stopping over a distance of a few inches which can kill you, whether or not it is the ground that does the stopping or Spock's Vulcan grip.
Well before the reaction forces that will physically tear or break your body occur, other severe physiological problems set in. First and foremost, it becomes impossible for your heart to pump strongly enough to force the blood up to your head. This is why fighter pilots sometimes black out when they perform maneuvers involving rapid acceleration. Special suits have been created to force the blood up from pilots' legs to keep them conscious during acceleration. This physiological reaction remains one of the limiting factors in determining how fast the acceleration of present-day spacecraft can be, and it is why NASA, unlike Jules Verne in his classic From the Earth to the Moon, has never launched three men into orbit from a giant cannon.
If I want to accelerate from rest to, say, 150,000 km/sec, or about half the speed of light, I have to do it gradually, so that my body will not be torn apart in the process. In order not to be pushed back into my seat with a force greater than 3G, my acceleration must be no more than three times the downward acceleration of falling objects on Earth. At this rate of acceleration, it would take some 5 million seconds, or about 21Ž2 months, to reach half light speed! This would not make for an exciting episode.
To resolve this dilemma, sometime after the production of the first Constitution Class starship—the Enterprise (NCC-1701)—the Star Trek writers had to develop a response to the criticism that the accelerations aboard a starship would instantly turn the crew into "chunky salsa."1 They came up with "inertial dampers," a kind of cosmic shock absorber and an ingenious plot device designed to get around this sticky little problem.
The inertial dampers are most notable in their absence. For example, the Enterprise was nearly destroyed after losing control of the inertial dampers when the microchip life-forms known as Nanites, as part of their evolutionary process, started munching on the ship's central-computer-core memory. Indeed, almost every time the Enterprise is destroyed (usually in some renegade timeline), the destruction is preceded by loss of the inertial dampers. The results of a similar loss of control in a Romulan Warbird provided us with an explicit demonstration that Romulans bleed green.
