Message posted by Andreas Parsch on November 02, 2006 at 12:03:36 PST:

> However, I still say that we cannot definitively
> state that our theories are correct, even to include
> Einstein's theory of relativity.

I agree, because we will probably _never_ be _definitely_ sure of any scientific theory.

> And you can't tell me that there aren't a number of
> young scientists out there who would love to poke a
> hole or two in the laws laid down by Einstein,
> Hawking, et al, regardless of the can of worms that
> would open.

This is indeed true! This fact is often ignored by "fringe scientists" (a.k.a. crackpots) who claim that their revolutionary new theory is suppressed by the "scientific establishment". If any break-through physics looks even remotely plausible ("Cold Fusion" ;-)), _hundreds_ of labs will jump and try to reproduce it.

> Even if the GR prohibition of lightspeed travel does
> hold up in the long run, there could be countless
> ways of getting around it that we haven't considered,
> simply because our understanding and knowledge of the
> universe is so limited.

This is of course true.

> Wormholes right now are the
> most-cited example of a possible workaround of the GR
> prohibition. Who can say how many other "shortcuts"
> are out there?

There have been any number of serious proposals for "shortcuts" of some kind, but essentially all of them (incl. wormholes and "warp-drives") come down to clever manipulation of space-time itself. The problem remains time-travel, because in all FTL "shortcut" proposals I have read, you automatically get time-travel as well. And there have been quantum mechanical calculations (which are _way_ beyond my comprehension, so I have to believe the physicists at face value ;-)), that any existing "time-machine" (technically a "closed timelike loop" in space-time) would self-destruct in a _very_ short timeframe.

Anyway, I'm sorry that this went a bit off-topic for DLR. But I think that when talking about the possibilities of extraterrestrial visitations, it's mandatory to know that interstellar travel is _not_ only a simple matter of improved technology (as opposed to, say, the development of flight from the Wright brothers to the SR-71). We definitely don't know all the basic laws of the universe, but we're not completely ignorant either ;-).

Andreas

In Reply to: Re: Probability of visitation posted by Chris McDowell on November 02, 2006 at 7:52:28 PST:

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