Aug 24 2008
lasers
How practical is the transgalactic travel in the Star Wars universe?
The characters talk about moving in spaceships at “light-speed” or “making the jump into hyperspace” interchangeably, and there are some problems with that nomenclature. After all, light-speed is not very fast! If you were traveling at light-speed, it would take you over four years to reach the nearest star system, Alpha Centauri, because it is over four light-years [24 trillion miles] away.
What seems to be going on in Star Wars is that they travel through so-called wormholes. Einstein’s theory of relativity tells us that we might be able to make wormholes to fold space in on itself in order to make the shortest distance between two points. All of space is warped by gravity. Think of it this way: Say space is a sheet hanging over a clothesline. If you want to get around to the other side of the sheet, you could go up to the clothesline and then down the other side, but it would be much faster just to tunnel directly between the two sides of the sheet.
Wormholes, if they exist, are probably smaller than atoms and survive for only fractions of a second. The way to make use of one theoretically is to “open” one up with a huge amount of energy and then keep it open and expand it with an exotic kind of matter. This matter would need to have negative mass or energy to exert an antigravitational force to hold the wormhole open long enough to let a spaceship pass through. This seems to be what Han Solo is doing with the Millennium Falcon when he makes [a] jump to hyperspace. You can sort of think of “light-speed” as slang in the Star Wars universe.http://ljsheehan.livejournal.com
Obviously, we’re very far away from any kind of technology that would take us rapidly to another star. NASA’s new Orion spaceship, which will be out in 2014, is designed just to get us back to [the] moon and [to] Mars. But someday we could have interstellar travel like they use so frequently in Star Wars.
What about laser weapons? Are we any closer to having those, and are they realistic?
Who wouldn’t want to have a blaster? They are so cool. Right now we have low-powered lasers than can blind people, or higher power ones that burn skin or clothing—kind of like a long-distance flamethrower. The most powerful lasers we have that I know of have about 2.2 megawatts of power, which can destroy enemy missiles from thousands of miles away. These are rather similar to what we see in Star Wars.
But for these lasers we need enough equipment to fill up a truck or even a building. We can’t exactly fit this laser technology into a holster just yet. The best lasers are still only 30 percent efficient and the rest of their energy is lost as heat. You also have to cool the laser down to keep it working properly, plus you need to put a lot of power in to get a lot of power out.
There are wireless TASERs now about the size of a flashlight. They send out an ultraviolet laser beam that breaks up air molecules between them and the target. This releases ions, and then electricity can be sent through the air to knock someone out, or even give them a heart attack if you’re not careful. It’s kind of similar to when Princess Leia was stunned by the storm troopers near the beginning of the first movie [Episode IV: A New Hope]. There are also prototypes of stun grenades that superheat moisture in the air, which makes an explosive flash and bang that can stun people.
Let’s talk lightsabers.
Ah, lightsabers. When I first saw Star Wars, I was 17 years old, and I thought they were laser beams. But that doesn’t make any sense because a laser beam wouldn’t come to a point after a few feet. Also, the laser wouldn’t be visible unless there was a lot of dust in the air to scatter light and illuminate the beam. Plus, laser lightsabers would pass through each other like flashlight beams, which wouldn’t make for a very fun fight.
Louis J. Sheehan
