Questions about UT smoke, lasers, and plasma.

[sethbrayman]

Originally Posted by Flyndaran

Plasma guns are Superscience. Do they really need such involved explanations to allow? Ah, what am I saying? I love me some self-consistent techno-babble.

Agreed, it is super science and handwavey, but the question is specifically about the explanation of how the SS weapon works. Please assume for the sake of this thread it is important to me.

If the plasma weapons had other flavor text or didn't mention its need to create a vacuum channel via laser I wouldn't have any questions about it.

[Flyndaran]

I meant to sound almost opposite to critical. I apologise for mangling my attempt at silliness. I wish I could blame my cold, but my sig is what it is for a reason.

Often with superscience, you have to change either the stats or the flavor text to fit in with the desired setting.

It seems like you may want to alter the description of how the result is achieved more than anything important to most PCs.

[Ulzgoroth]

Originally Posted by sethbrayman

Is this laser somehow more powerful than the ones used as weapons just by themselves? Does it have properties that allow it to ignore the things that stop lasers?

It seems to me that, simply, anything that stops lasers will stop the laser that is required to create the evacuated channel.

To put it another way, if a very powerful laser that uses the normal atmo as a lense i.e. rainbow lasers, is stopped by radiant prism smoke, then that applies to any other laser within the rules for the smoke.

*EDIT: Also it doesn't make sense that something would be be non-transparent to the plasma bolt, but not to the laser. That's putting the cart before the horse, to steal some of your analogy. The plasma will explode if it touches air or anything other than vacuum, the laser must destroy the air between the bolt and its target otherwise it explodes on contact with the air or smoke. Smoke stops lasers (most of them).
**EDIT: Your analogy implies that the laser making the channel is more powerful (a bulldozer vs a cart) and more able to cut through smoke (the caltrops) than the lasers used as weapons by themselves. If that were true then smoke stopping deadly lasers would not work. According to the rules I've quoted from UT prism smoke provides significant DR vs most lasers, so it can not be true, assuming enough smoke to stop a deadly laser is used vs the plasma weapon.

It may well be that the power required for the vacuum-generating laser is actually high enough to be a weapon laser. That would still not be the biggest plausibility problem with plasma guns. They exist because SF writers can't resist using the name, not because they're good science.

There are two things that limit how much laser energy a given bit of air will stop. One is transparency, and the other is the amount of energy that will blast the air out of the path. For normal lasers used in atmosphere (that is, not X-ray or gamma ray lasers), the air is mostly transparent. Smoke makes the air less transparent. But the function of this laser requires that it dump enough energy to drive every bit of clear air past the 'blown away' point. And adding smoke isn't going to significantly increase the amount of energy it takes to blast any given volume to vacuum.

[sethbrayman]

Flyndaran, no offense taken! I just wanted to be clear so I don't get too many replies telling me not to worry about it :)

I think plasma weapons will soon come into use against my PC in a game (the PC knows this) and I want to have a good, thought out, defensible reason for saying "this smoke might help me in this situation". My GM is very much about things being internally consistent even though we are using SS in some cases.

I am torn about the setting consistency of course, if it does effect plasma then everyone would know that, at least anyone who commonly uses plasma weapons/is trained in them.

Depending on what comes out of this thread I'll either forget about it or take it to the GM so its not a surprise if I pop smoke vs plasma.

[sethbrayman]

Originally Posted by Ulzgoroth

It may well be that the power required for the vacuum-generating laser is actually high enough to be a weapon laser. That would still not be the biggest plausibility problem with plasma guns. They exist because SF writers can't resist using the name, not because they're good science.

There are two things that limit how much laser energy a given bit of air will stop. One is transparency, and the other is the amount of energy that will blast the air out of the path. For normal lasers used in atmosphere (that is, not X-ray or gamma ray lasers), the air is mostly transparent. Smoke makes the air less transparent. But the function of this laser requires that it dump enough energy to drive every bit of clear air past the 'blown away' point. And adding smoke isn't going to significantly increase the amount of energy it takes to blast any given volume to vacuum.

Can you explain how a laser wouldn't be stopped by the smoke in this example? I ask because:

• If it doesn't interact with the radiant prism smoke then it does not create a channel, thus the smoke stays and the plasma explodes on contact. For example if it was a gamma laser.
• If it does interact then it can't "push" in the normal sense, it must burn a hole from one side to the other for the bolt to pass though. Since smoke does stop lasers that burn holes through things, then the smoke would stop this type of laser (assuming enough of it).

[Ulzgoroth]

Originally Posted by sethbrayman

Can you explain how a laser wouldn't be stopped by the smoke in this example? I ask because:

• If it doesn't interact with the radiant prism smoke then it does not create a channel, thus the smoke stays and the plasma explodes on contact. For example if it was a gamma laser.
• If it does interact then it can't "push" in the normal sense, it must burn a hole from one side to the other for the bolt to pass though. Since smoke does stop lasers that burn holes through things, then the smoke would stop this type of laser (assuming enough of it).

Lasers can never 'push' air significantly. The momentum transfer from them is very small. What they can do is super-heat it and make it blast out of the way. Adding smoke to the air doesn't make that harder.

[Adversary]

Originally Posted by sethbrayman

Flyndaran, no offense taken! I just wanted to be clear so I don't get too many replies telling me not to worry about it :)

I think plasma weapons will soon come into use against my PC in a game (the PC knows this) and I want to have a good, thought out, defensible reason for saying "this smoke might help me in this situation". My GM is very much about things being internally consistent even though we are using SS in some cases.

I am torn about the setting consistency of course, if it does effect plasma then everyone would know that, at least anyone who commonly uses plasma weapons/is trained in them.

Depending on what comes out of this thread I'll either forget about it or take it to the GM so its not a surprise if I pop smoke vs plasma.

How about this, as a technobabble solution: the lasers used to make channels for plasma weapons use a frequency of light that is highly efficient at burning through/creating evacuation channels in atmosphere, but highly inefficient for damaging anything solid. In other words, a low-energy laser of this type can create a channel through air, even non-transparent air, but you can't make a super-weapon out of it.

Once you have this baseline established you can play with the specifics to get the game effect you want. Maybe there is a particular type of smoke that is[I] effective against this laser...but be careful using it, because the plasma beam will explode at whatever depth the laser's penetration of the cloud fails--which will not be the edge of the cloud, but some random point inside it.

[Fred Brackin]

Originally Posted by sethbrayman

Agreed, it is super science and handwavey, but the question is specifically about the explanation of how the SS weapon works. Please assume for the sake of this thread it is important to me.

If the plasma weapons had other flavor text or didn't mention its need to create a vacuum channel via laser I wouldn't have any questions about it.

More than superscience what you have here is two flavors of _bad_ science and predictably enough trying to referee between them with good scicne doesn't work very well.

First, the game rules about weapons grade lasers being stopped by smoke are bad science. They have a single hex of smoke that blocks normal vision (-10 penalty) giving DR 10 and basically stopping a 3D laser.

Somebody can come along and work out the equivalency of normal lighting to watts of laser output if they want to bt why don't we stick to comparing lasers to lasers and say that a smoke hex that stops normal vision will also stop a common laser pointer.

Said laser pointer is limited to 5 milli-watts by US law. A modest real world laser such as the US Navy has just deployed will be in the vicinity of 100 kilowatts. Just to put everything in the same units 100 kw is equal to 100,000,000 milli-watts.

From this we can see that the weapon laser is 20,000,000 times as intense as the laser pointer. It would take 20 million times as many smoke particles to absorb the weapons laser. Fairly predictable when Gurps would normally measure the penetration of the weapons laser in millimeters of RHA steel (and get a value of about 3.5mm of RHA).

Incidentally, this is a real world laser. By the standards of sci-fi laser it would be only a pistol and possibly a small one at that.

So single hexes of regular smoke would have no measurable effect on a weapons grade laser. Bad science.

As you've asked a laser that would heat a horizontal column of air so much that it would expand enough to create a channel of near vacuum and hold it open would indeed have to be even stronger than a simple weapon laser.

[sethbrayman]

Originally Posted by Ulzgoroth

Lasers can never 'push' air significantly. The momentum transfer from them is very small. What they can do is super-heat it and make it blast out of the way. Adding smoke to the air doesn't make that harder.

I agree that they super heat it, but disagree that adding smoke doesn't make it harder. Making it harder is exactly what smoke does, it forces the laser to dump more of its energy before hitting the intended target. The smoke absorbs more from the laser than normal air would and in the case of prism smoke it specifically diffuses that energy before it can pass through it. The energy, heat and light, are affected by the smoke in the description of the smoke itself.

[sethbrayman]

Originally Posted by Adversary

How about this, as a technobabble solution: the lasers used to make channels for plasma weapons use a frequency of light that is highly efficient at burning through/creating evacuation channels in atmosphere, but highly inefficient for damaging anything solid. In other words, a low-energy laser of this type can create a channel through air, even non-transparent air, but you can't make a super-weapon out of it.

Once you have this baseline established you can play with the specifics to get the game effect you want. Maybe there is a particular type of smoke that is[I] effective against this laser...but be careful using it, because the plasma beam will explode at whatever depth the laser's penetration of the cloud fails--which will not be the edge of the cloud, but some random point inside it.

I would like for the laser to follow the rules that other lasers in UT do and simply be effected by smoke depending on the type of laser and type of smoke. My argument is that, based off of the description of plasma weapons, they would do exactly what you describe and in fact "explode at whatever depth the laser's penetration of the cloud fails".

Does that sound appropriate without changing either the flavor text or the rules for lasers and smoke?