From: mar@physics.su.OZ.AU (David Mar)
Newsgroups: rec.games.frp.advocacy
Subject: Re: Is it real, or is it SF?
Date: 29 Jul 92 01:46:36 GMT
Organization: School of Physics, University of Sydney, Australia

Nick_Janow@mindlink.bc.ca (Nick Janow) writes:
>I said nothing about _rigorous_ scientific extrapolation.  If the FTL drive
>is essentially a "black box" added to give characters access to other star
>systems, then it is fantasy.  If you give an explanation for the drive that
>is not directly contradicted by anything in the known laws of your gaming
>universe, extrapolate the effects of that science for the parts of the
>universe the players will encounter, and nothing in the game contradicts
>the science you have proposed, then it could be considered SF.

Okay, that seems a little more reasonable. Can you tell me what this
explanation (taken directly from the campaign background I hand out to
my players) qualifies as:

The hyperdrive skews the normal set of spatial dimensions into an
orthogonal set, so that normal propulsion methods move a ship along at
sub-light speeds through the orthogonal "hyperspace". When the dimension
skewing is relaxed, the ship is found many light years from its original
position in real space. Only theoretical physicists and drive engineers
really know how it all works. The hyperdrive is characterised by trips
taking a finite amount of time. While in the dimension-skewed state,
interaction with real space is possible, but not very easily. Such
interaction would involve a part of the ship relaxing into real space,
which naturally puts mechanical stresses on its construction. Also, when
part of the ship extends into real space, the ship naturally cannot exceed
(real space) lightspeed. Course changes can be made while in the skewed
state, but navigation must be done either by dead reckoning or by letting
some of the ship's sensors relax into real space. The dimension skewing
can be performed anywhere in real space, and hyperdrive ships routinely
leave planetside docks by skewing while on the landing pad. Returning a
ship to real space is usually done some distance from any large body,
since trying to do this safely on a landing pad would require enormous
amounts of luck and courage.

>GM's hate it when players point out why something in the game universe
>won't work, or something the GM hadn't considered (and hadn't planned
>for) would work (ruining hours of GM's labour).

Yes, I certainly agree with you on this point!

>> Under our current understanding of physics, neither psionics nor FTL travel
>> are likely to be possible. In fact, I would argue that psionics are more
>> likely to be possible than FTL travel.
>
>Oh, I'd love to read your arguments in favour of the possibility of psionics!
>Please post them.  >:-)

Ah, but I said psionics were only _more_ likely than FTL travel. This is
because I consider FTL travel to be fundamentally impossible (until convinced
otherwise by some _extraordinary_ evidence to the contrary). FTL _violates_
several physical laws which, up to now, seem to be essentially inviolable.
Psionics would "merely" require the highly creative use of laws we have -
it would not _necessarily_ violate laws currently believed to be true. (I am
willing to be convinced otherwise, if someone has a good enough argument.)
I never said I believed that psionics were likely to be real.

>The problem is that if the GM doesn't know if it is possible (in the gaming
>universe), he has to make a random decision about it.  Later, a similar
>situation comes up, and another random decision about what is or isn't
>possible in that universe is made.  Still further on, the players try
>something else, and it turns out that it is possible according to the
>first decision, and impossible according to the second; the two decisions
>were mutually incompatible.  The GM then has to backtrack and say that
>something that happened didn't happen, or else come up with a third
>decision about the universe which allows the two previous decisions to be
>compatible.  This usually involves a nonsense explanation, and the game
>moves into the realm of fantasy.

Yes, I agree that this can be a problem. I also see a few areas in my own
psionics rules where this could conceivably happen. I shall attempt to
make them a lot tighter (I knew this discussion was good for something!).
But you can also get around this problem by keeping careful track of such
decisions made during play and applying them uniformly thereafter. It would
be a pain to do, but do you think it is possible for a "soft" SF explanation
to evolve into a "hard" one by this method? Or do you _need_ the core rules
graven in stone before you begin?

David Mar.                              mar@astrop.physics.su.OZ.AU
Astrophysics Department, University of Sydney  NSW  2006, Australia.