From: Bradford Holden <holden@o...>
Date: Fri, 12 Sep 1997 12:19:19 -0400
Subject: Sci-Fic physics was Re: Faster Than Light Travel -
Alright, I will toss in my 2 cents about all this. Tts been awhile since I took General Relativity so I might get some of the details screwy. First, Tachyons. The idea behind Tachyons is simple, special relativity says you cannot go the speed of light with something with mass. If something is massless (light, neutrinos, gravitons, etc etc-ons) it goes exactly at the speed of light. Tachyons go only faster then the speed of light. As someone else mentioned, as you add more and more energy to a tachyon, it goes slower and slower. That is how the equations work (screwy, eh?) but at no point do these things travel slower then the speed of light. The big problem with tachyons, is there are no predictions on how they behave except that they go faster then light. Its hard to detect something when you have no clue on how it should interact with the other things we understand (the so-called tardyons). Most likely, they do not interact at all. When you work on special relativity and start postulated things moving faster then light all kinds of weird things start happening. We once had a problem on the tachyon telephone. If we could create tachyons and send information with them, it turns out you call backwards in time. This is a problem (ring ring, Hello? Sell ALL your Microsoft stock now, it will drop through the floor in a week!) as casuality just goes right out the window. Hence, most physicists don't even think about tachyons, because if they can interact with our universe at all, they just break a whole lot of rules that we know and love. So the other favorite way to travel faster then the speed of light is by warping space-time. Usually this involves something like a wormhole. Now the problem with GR is it starts to break down when you talk about things called singularities. A singularity forms at the core of a black hole, for example. There are black holes that can form where you can fall through (you don't actually hit the singularity) but know one has any clue what would really happen. In the past, when a theory has a singularity, it means we don't know what is going on. So we are gonna have to wait for a more complete theory to understand this. cheers brad