FTL Travel Question

[Tdata]

While I figure a game making site isn't the best place for this, though it could be, I have a question that has plagued me for quite awhile.

According to Einstein's theory of special relativity, any particles with non-zero mass would require infinite energy to reach the speed of light. Now if I remember my physics classes correctly, this is do to the fact that the mass also becomes infinite.

So, by the equation

, you would have your energy.

Am I making any sense?

 

[candle]

I have actually been planning on making a topic about FTL travel, but it was geared more towards the current theories based in sci-fi media rather than any actual science and what people thought about them.

 

[Perihelion]

What, are you implying that you want to use the energy in that equation to push your spaceship to lightspeed? That doesn't work for two reasons (well, I guess one).

1. The energy in that equation is basically the object's kinetic energy, which is a property of the object. You can't tap into it like I think you're implying; it doesn't work like that. I mean, can you use a car's kinetic energy to make it go faster? No, because that would be silly.
2. I would like to know how you would use that energy. Rockets need reaction mass, although other kinds of spaceship drives (e.g. light sails) can get away without it. Well, okay, I guess you can power it with radiation pressure like a light sail or something. Btw, it is physically impossible to carry enough reaction mass to accelerate to the speed of light because the more mass you carry, the more energy you need to get there.

If you want to know about special relativity, the guy who lives across the hall from me took a class on it a couple months ago.

Anyway, you run into problems with every interpretation of FTL travel. Your best bet is probably wormholes, which need negative matter to keep the mouth open but are probably the most realistic approach, or if you want something more mobile, look into Alcubierre drives and dark energy.

 

[Perihelion]

Okay, sorry, let me clarify. You can convert kinetic energy into other kinds of energy, although I have no idea what kind of mechanism you'd use to make that useful for space travel, which upon reflection was my original point with #2 and not what I actually said, but whatever, it could probably be done somehow. But like, think of a waterwheel. If you stick one in a river and hook it up the right doodads, you can use its turning to generate electricity, but you take kinetic energy from the water in doing so. The main point is that you can't get something for nothing in physics. There's no such thing as free energy.

Okay, yes, there is something called free energy, but that's different! I digress, in any case.

 

[Tdata]

True, TANSTAAFL.