Does teleport maintain intertia?

[WingedKagouti]

Originally Posted by Varyon

Personally, I don't have a problem with teleportation maintaining relative velocity. Absolute velocity is a different story, but more just because it would be a nightmare to figure out at the table the direction and speed imparted by teleportation than because of game balance concerns.

Absolute has the major issue of "Absolute in relation to what?" The planet? The solar system? The galaxy? The Big Bang? Those will all be different.

[malloyd]

Originally Posted by WingedKagouti

Absolute has the major issue of "Absolute in relation to what?" The planet? The solar system? The galaxy? The Big Bang? Those will all be different.

Despite people wanting to use it like this, the Big Bang isn't a valid spatial reference. It happened at every point in the universe, and the points in the universe aren't co-located, or even at rest with respect to each other.

[RGTraynor]

Originally Posted by whswhs

But a more basic point is that, if you want to run a game where players cast cool spells, and confront adversaries, and in general roleplay, but you use an interpretation of teleportation where things like conservation laws apply and where a clever player can come up with ways to use them to gain advantages for their characters—then you're going to see game time being spent on talking about the technicalities of physics rather than on dramatic actions. And if that's not the flavor you're aiming for then you've got a problem.

Most games can stand a few minutes worth of discussion about such things, especially when they tend to be one-offs. (Beyond which, GURPS -- being one of the most cerebral RPGs out there -- isn't all that fertile an environment for gamers who flinch in horror at such things.) Even the most four-color of games aren't 100% "dramatic actions." A party insistent on going off the rails on such discussions, and/or a GM incapable of reining them in, has much deeper problems than dealing with teleportation physics.

And, ultimately, the game is about what the players and GM want it to be about. If a game has fewer dramatic actions because the group's happily spending a half hour hacking over a physics hypothetical, more power to them.

[Varyon]

Originally Posted by WingedKagouti

Absolute has the major issue of "Absolute in relation to what?" The planet? The solar system? The galaxy? The Big Bang? Those will all be different.

Relative to the destination. Earth is moving at around 30 km/s relative to the Sun, so if you teleported to the Sun's surface, you'd be moving with velocity vector (adjusted for any vector added in thanks to the Earth's ~450 m/s rotation), in the same direction as the Earth was heading in its revolution at the moment you teleported.

[whswhs]

Originally Posted by RGTraynor

Most games can stand a few minutes worth of discussion about such things, especially when they tend to be one-offs. (Beyond which, GURPS -- being one of the most cerebral RPGs out there -- isn't all that fertile an environment for gamers who flinch in horror at such things.) Even the most four-color of games aren't 100% "dramatic actions." A party insistent on going off the rails on such discussions, and/or a GM incapable of reining them in, has much deeper problems than dealing with teleportation physics.

Sometimes the GM has to be proactive in defining what is or isn't appropriate for a particular campaign. When I ran a campaign set in Middle-Earth, for example, I said at the start of the first session that we would face to black between the first kiss and the birth of the first child. And it was a good thing I did!

[Plane]

Originally Posted by Varyon

Alternatively, there's this, which quotes Psionic Powers (which I lack to check) as allowing you to shed relative velocity (with the example of teleporting safely to the ground during a fall). You're more likely to be disoriented from such a Warp than normal (-5 to the Body Sense roll), of course.

I don't really like a fixed -5 penalty regardless of what the difference in relative velocity is. Couldn't we somehow get a range of possible penalties based on the actual difference?

It seems like for example it should be more disorienting to teleport onto a mach-speed bullet-train than onto a horse-drawn wagon.

B550 gives a -5 penalty to hit an object moving 15 yards per second. Could we just use that to penalize Body Sense?

I guess this makes it too hard at high speed levels. It's a shame body sense is a skill and not an aspect of the Warp power itself or we could just use the Long Range enhancement.

Wasn't there some pyramid guide for applying modifiers to skills?

[Not another shrubbery]

Originally Posted by Plane

I don't really like a fixed -5 penalty regardless of what the difference in relative velocity is. Couldn't we somehow get a range of possible penalties based on the actual difference?

It seems like for example it should be more disorienting to teleport onto a mach-speed bullet-train than onto a horse-drawn wagon.

B550 gives a -5 penalty to hit an object moving 15 yards per second. Could we just use that to penalize Body Sense?

I guess this makes it too hard at high speed levels. It's a shame body sense is a skill and not an aspect of the Warp power itself or we could just use the Long Range enhancement.

Wasn't there some pyramid guide for applying modifiers to skills?

I guess if you wanted a non-fixed penalty, you could base it on the difference in relative velocity and use that number in the SST. It's not that big a deal though, which might be why PK glossed over it in Psionic Powers (and why he included the Gyroscopic enhancer in Autoteleport).

[Anthony]

Originally Posted by malloyd

Despite people wanting to use it like this, the Big Bang isn't a valid spatial reference. It happened at every point in the universe, and the points in the universe aren't co-located, or even at rest with respect to each other.

It's possible to measure velocity relative to the cosmic microwave background, but I think 'absolute' actually just meant 'zero velocity relative to original vector'. Which still isn't absolute because general relativity, but is reasonably well defined for ordinary distances PCs will be concerned with. And probably means teleporting more than a thousand miles or so will kill you.

[Varyon]

Originally Posted by Anthony

It's possible to measure velocity relative to the cosmic microwave background, but I think 'absolute' actually just meant 'zero velocity relative to original vector'. Which still isn't absolute because general relativity, but is reasonably well defined for ordinary distances PCs will be concerned with. And probably means teleporting more than a thousand miles or so will kill you.

Yeah, I don’t think “absolute” velocity really exists when you bring general relativity into the equation. What I meant was that you still have the same velocity relative to the destination as you had when you started (which is the same as your “zero velocity relative to original vector”), and calling that “absolute” is a useful shorthand that I thought most people would understand. It’s the situation where teleporting too far east launches you into the air, while teleporting too far west slams you into the ground.

[malloyd]

Originally Posted by Anthony

It's possible to measure velocity relative to the cosmic microwave background.

Sort of. Locally. Two objects completely at rest with respect to the cosmic microwave background will be moving relative to each other unless they occupy the same point. Admittedly not by enough to matter much unless they are separated by interstellar or even intergalactic distances, but the principle matters.