[3.5] Abrupt Jaunt

[Alexei]

So... we ran into an interesting doubt today.
A bit of situation: I am playing a level 3 mage (with Abrupt jaunt) and I wanted to jump down a high wall, then abrupt jaunt before reaching ground to avoid fall damage.
As we didn't reach an agreement whether this would work or not, I did it the mundane way: prepare a rope and go down.

Would AJ make you appear with any "carried" speed (fall speed, or anything) from before the Jaunt? Or should it work? It's like the WoW Mage Blink spell use to jump down cliffs without dying

[Kethrian]

While there is probably no official answer, Blink is a good spell to reference.  It has you randomly shifting between the material and near ethereal, and when falling, you end up taking half damage, because the "speed" does transfer with you, but the ethereal doesn't have gravity to accelerate your fall further.  But really, you should just get Feather Fall, as that spell is specifically designed for this kind of problem.

[Hallack]

Very much a grey area.  A buddy and I have went around on the Position and Momentum when considering Teleport effects several times. 

It's a grey area in which we disagree

[Arturick]

Not an official answer, but I lean towards the preservation of momentum.

[littha]

Preservation of momentum has its own issues... Now your thinking with portals.

[Kremti]

Speedy thing goes in, speedy thing comes out.

-G

[spacemonkey555]

Momentum is a pain with teleportation unless you handwave it to work in the user's favor. Teleport from the equator to the south pole, great, you need to decelerate 1000 mph very, very rapidly right after you arrive. That could be fairly uncomfortable.

It might be a good way to effectively ban long distance teleportation if that's what you're after though. Even if you stay at the same latitude, you'd either shatter your legs or be thrown up in the air depending on whether you ported with or against the spin of the planet.

Best solution is to have the porter match momentum on arrival.

[Kethrian]

Momentum is relative anyway.  If you are not moving in relation to your surroundings from where you leave, then you will not be moving in relation to where you arrive.  If you are falling at terminal velocity when you leave, you will be falling at the same rate where you arrive.  If you try to use momentum as an absolute, then teleporting a quarter of the way around the world latitudinally will either have you crater into the ground or get flung out into space.

and besides, this is D&D, the world could be a flat disc or a cube or the inside of a giant ring or...

[spacemonkey555]

Momentum is relative anyway.  If you are not moving in relation to your surroundings from where you leave, then you will not be moving in relation to where you arrive.  If you are falling at terminal velocity when you leave, you will be falling at the same rate where you arrive.

Can you quote that rule for us?

If you try to use momentum as an absolute, then teleporting a quarter of the way around the world latitudinally will either have you crater into the ground or get flung out into space.

Yeah, that's what I said.

[Kethrian]

Momentum is relative anyway.  If you are not moving in relation to your surroundings from where you leave, then you will not be moving in relation to where you arrive.  If you are falling at terminal velocity when you leave, you will be falling at the same rate where you arrive.

Can you quote that rule for us?

If you try to use momentum as an absolute, then teleporting a quarter of the way around the world latitudinally will either have you crater into the ground or get flung out into space.

Yeah, that's what I said.

I'd recommend a book called "Why does E=MC^2?"  It explains momentum and relativity, plus spacetime, why you can't exceed the speed of light, why time distorts as you move faster, etc.

But if you're looking for a D&D ruling about momentum, you won't find one, because D&D doesn't even cover things like planetary spin.  Its logic comes from things like the sun moves through the sky instead of the world revolving around the sun, the world could be flat instead of round, outer space might not be a vacuum, planetoids could be the corpses of dead gods, microscopic things don't really exist, fire/air/earth/water are elements instead of hydrogen/helium/etc., stars are the souls of people who exploded from too much awesome on the positive energy plane...

[spacemonkey555]

I'd recommend a book called "Why does E=MC^2?"  It explains momentum and relativity, plus spacetime, why you can't exceed the speed of light, why time distorts as you move faster, etc.

Cute, you think a book that explains real world physics like not being able to exceed the speed of light will help provide a ruling on instantaneous teleportation through the astral plane. Do you check the bible before your cleric casts a spell?

[SneeR]

Let's be nice, now.

I have always been of the persuasion that teleportation stops momentum. I have had players do exactly that: jump down a cliff, then teleport the last fifty feet down for safe landing. I think that the ability to carry object momentum (like the Portal games) should be specific, because it opens up too much shenanigans. One item that I am thinking of is the set of iron rings that essentially are Portals from the DMG. They specifically say that you instantly travel through space as if there were no space there.

[Kethrian]

I'd recommend a book called "Why does E=MC^2?"  It explains momentum and relativity, plus spacetime, why you can't exceed the speed of light, why time distorts as you move faster, etc.

Cute, you think a book that explains real world physics like not being able to exceed the speed of light will help provide a ruling on instantaneous teleportation through the astral plane.

Hey, if you're gonna use real-world physics for rules in a fantasy setting, you may as well do proper research and get it right.  Otherwise, just stick to the fantasy physics that are relevant to the fantasy setting, and leave the real-world stuff out of it.  Y'know, like referencing Blink, which is the only spell I know of which covers this kind of thing within the D&D rules.

Do you check the bible before your cleric casts a spell?

Sure, show me a bible for Pelor or Obad-Hai or any of the other D&D gods, and I'll read it through for proper RP perspective on my cleric of that god.

[ksbsnowowl]

Momentum is relative anyway.  If you are not moving in relation to your surroundings from where you leave, then you will not be moving in relation to where you arrive.  If you are falling at terminal velocity when you leave, you will be falling at the same rate where you arrive.

Can you quote that rule for us?

Immovable Rod

This rod is a flat iron bar with a small button on one end. When the button is pushed (a move action), the rod does not move from where it is, even if staying in place defies gravity. Thus, the owner can lift or place the rod wherever he wishes, push the button, and let go. Several immovable rods can even make a ladder when used together (although only two are needed). An immovable rod can support up to 8,000 pounds before falling to the ground. If a creature pushes against an immovable rod, it must make a DC 30 Strength check to move the rod up to 10 feet in a single round.

Moderate transmutation; CL 10th; Craft Rod, levitate; Price 5,000 gp.

If momentum were not relative, you could not create an effective ladder with several of them.

[spacemonkey555]

Immovable rods don't speak on the subject of dividing a teleporting character's momentum into 2 components arbitrarily, and then modifying one so that it is perfectly safe and modifying the other to maintain its lethality.

There's a difference between relative momentum, and magically translating relative momentum when subject to a teleport spell. Saying that momentum is relative is pointless, it's a truth that is based on the fact that an person can't instantaneously teleport. Obviously the rules as intended is that you're safe from changes to your relative momentum when porting.

If you say that the rules don't say you stop falling when you port so you should keep falling, that's a perfectly reasonable statement. If you say that teleporting normalizes your momentum relative to the world when you port that's also a perfectly reasonable statement.

If you say that momentum is relative so you should maintain lethal falling momentum while simultaneously changing lethal frame of reference momentum to be safe, that's weird.

[Kethrian]

Immovable rods don't speak on the subject of dividing a teleporting character's momentum into 2 components arbitrarily, and then modifying one so that it is perfectly safe and modifying the other to maintain its lethality.

If you're referring to the difference between absolute and relative momentum, nothing does.  Everything uses relative momentum, and you just have to figure out how it best applies.

There's a difference between relative momentum, and magically translating relative momentum when subject to a teleport spell.

I don't think you understand what relative momentum is.  If you are moving forward at 60kph, then if you teleport while maintaining relative momentum, you will be moving forward at 60kph in your new location.  You are maintaining the same momentum relative to your surroundings.

Saying that momentum is relative is pointless, it's a truth that is based on the fact that an person can't instantaneously teleport. Obviously the rules as intended is that you're safe from changes to your relative momentum when porting.

What?  It all comes down to what you are comparing your momentum to.  You could compare it to the local area where you appear, to your location relative to the sun, to the solar system, the galaxy...  but I think we can all agree that it should be relative to the local area.

If you say that the rules don't say you stop falling when you port so you should keep falling, that's a perfectly reasonable statement. If you say that teleporting normalizes your momentum relative to the world when you port that's also a perfectly reasonable statement.

Normalizes?  If you mean halts your relative momentum so you aren't moving at all when you appear, okay.

If you say that momentum is relative so you should maintain lethal falling momentum while simultaneously changing lethal frame of reference momentum to be safe, that's weird.

What is this, I don't even...

[spacemonkey555]

If you say that momentum is relative so you should maintain lethal falling momentum while simultaneously changing lethal frame of reference momentum to be safe, that's weird.

What is this, I don't even...

Sigh... Momentum has a vector and a magnitude, teleport changes both so you don't become a wet smear at the new location due to the change in frame of reference that suddenly doesn't match your original momentum. Too much magnitude or incorrect vector, boom, dead. Why must it maintain some percentage of the magnitude and vector in order to maintain falling "relative momentum"? You're moving through another plane of existence, this is not like that portal game (although it could be with the right spell or item).

Your "law of conservation of relative momentum" is not a dnd rule that I can find. That's why I asked you to quote the rule.

[Kethrian]

Sigh... Momentum has a vector and a magnitude, teleport changes both so you don't become a wet smear at the new location due to the change in frame of reference that suddenly doesn't match your original momentum. Too much magnitude or incorrect vector, boom, dead. Why must it maintain some percentage of the magnitude and vector in order to maintain falling "relative momentum"? You're moving through another plane of existence, this is not like that portal game (although it could be with the right spell or item).

Where does it say that Teleport changes vector or magnitude?  It only changes location from what I can see.

Your "law of conservation of relative momentum" is not a dnd rule that I can find. That's why I asked you to quote the rule.

Falling rules for Blink.  Only difference between it and Teleport is that Blink uses the near ethereal, while Teleport uses the astral.

Your "loss of all momentum" rule is not a D&D rule that I can find.  Please quote me a counter-ruling.

[spacemonkey555]

Blink isn't teleport, ethereal isn't astral, and if you can't see that you have to change momentum if you teleport to the far side of the planet, discussing this with you is pointless. I'm not really sure you even understand the word momentum. Losing all momentum isn't a thing I ever suggested, it would be as fatal as having the wrong momentum.

[linklord231]

My group used to play with the idea that momentum is conserved, until the party wizard started throwing the party fighter at things with pairs of DDoors.  We collectively decided that momentum is not conserved, because it made a saner game experience than human cannonballs.