Anti-Matter Beams

[All Seeing Eye]

We've seen countless times on Trek that ships often use Anti-Matter particles such as for example when the Dominion used Anti-Proton beams to try and detect the cloaked Defiant, now its this specific example that I have a question about... When Matter comes into contact with Anti-Matter they annihilate each other, since all atoms have protons in their nucleus as soon as these Anti-Protons hit the hull of the Defiant the Anti-Protons should have reacted with the Protons in the Metallic Alloy of the Ablative armour but yet nothing happens? I mean WTF? the Defiant had no shields up because we've heard countless times that you cant have shields up when the cloak is active. You cant argue that the Cloak bends the Anti-Protons around the ship because its fact that weapons can be fired on a ship when its cloaked and an Anti-Proton beam is no different than any other energy beam like a phaser.

Also in combat when a ships shields have failed why continue firing phasers? why not just fire an Anti-Proton beam and turn the hull of the enemy ship into a Matter/Anti-Matter reaction?

 

[Timo]

I don't see how we can say that "nothing happens". Most probably a lot happens: the beam hits the hull, trillions of little annihilation events launch radiation in all directions, and the sensors of the Jem'Hadar ships pick this up and observe the presence of the cloaked ship.

You are thinking in terms of a certain magnitude of antiproton beam. But why waste lots and lots of antiprotons when a relatively weak beam will do the job equally well? The total amount of energy released when the antimatter beam hits need not be greater than what is needed to light up a bulb.

Also, it's probably difficult to scale up the antimatter beam to release any more energy than that. Not to mention that a spray of particles like that is not going to be a very agile weapon. Phasers work at warp speeds when needed. Would an antiproton beam do that?

Also, a beam of antiprotons would disperse itself quickly through Coulomb repulsion between the negatively charged antiprotons. Not a problem in sensor applications, but it means difficulties for scale-up.

Timo Saloniemi

 

[JuanBolio]

What Timo said.

 

[Forbin]

What DID Timo say?!

 

[Forbin]

btw, who says ablative armor is metallic? I don't think it was ever mentioned what it's made of. It's there to ablate, it has to be some substance that CAN ablate and dissipate a beam weapon's energy.

 

[All Seeing Eye]

Forbin said:
btw, who says ablative armor is metallic? I don't think it was ever mentioned what it's made of. It's there to ablate, it has to be some substance that CAN ablate and dissipate a beam weapon's energy.

Well since shots of the Defiants hull look Metallic I assume thats what it is and whether its metallic or not since its obviously physical its still going to comprise of protons anyway.

 

[Timo]

To be sure, we don't even really know whether the ablative armor is physical matter.

I mean, yeah, the name suggests that something ablates (is blown away). But we never see anything blown away in macroscopic amounts. If the armor is solid matter, it's replaced "online" somehow - perhaps by constantly beaming more matter in place of the lost parts.

"Past Tense" describes the armor in these terms (emphasis mine):

O'Brien: "The [transporter] beam was just reacting to the accumulation of chroniton particles in the ship's hull. [..] They're emitted by the cloaking device. Sometimes they become lodged in the ship's ablative armor matrix."

So the armor is more or less equated with the ship's hull. Might mean physical matter, then. But that's the only description of the properties and nature of ablative armor we get in all of DS9.

Personally, I'd like to think that the ablative armor is a thin coating at most a few inches thick, almost completely transparent and thus invisible to us. It would consist of very un-dense, aerogel-like matter, easily ablated and easily replaced. Even though denser material would be better at carrying away the weapon energies, this gossamer stuff would more easily replenish itself in a matter of nanoseconds, using either rudimentary transporter technologies or a series of tiny dispensers all over the ship's surfaces.

But that's just me.

Timo Saloniemi

 

[Christopher]

I agree about the antiproton beams. Sure, each collision causes an annihilation event, but it's a tiny one that just gives off a single gamma-ray photon and maybe a stray particle or three. It takes trillions of those at once to cause the kind of big 'splosions we associate with antimatter weapons and such. Heck, a ship flying through space is going to be struck by the occasional stray antiproton anyway, what with all the cosmic radiation out there. Something like the "pure antiproton beam" of the Doomsday Machine would have to be an extremely dense particle beam to function as described (and a pure antiproton beam would actually be a lousy long-range weapon due to its mutual repulsion causing it to dissipate quickly).

In real life, there is research underway into using antiproton beams to destroy cancer cells:

http://www.sciencedaily.com/releases/2006/10/061031141340.htm

This can be safe because a limited number of proton-antiproton annihilations within the body isn't going to release enough energy to do much damage beyond the immediate vicinity of the targeted tumor. With something the size and density of a starship hull, an antiproton detection beam wouldn't cause more than a slight abrasion of the surface.

 

[ahkyahnan]

Christopher said:
Something like the "pure antiproton beam" of the Doomsday Machine would have to be an extremely dense particle beam to function as described (and a pure antiproton beam would actually be a lousy long-range weapon due to its mutual repulsion causing it to dissipate quickly).

I'm just quickly posting off the top of my head here, so if I haven't thought this through enough forgive me, but aboard ship antimatter is kept separate from matter by containment fields. Could some sort of containment field be emitted with and around the antiproton beam, sort of like a garden hose containing water? Bad analogy probably but just something that popped in my head before I have to shut down the internet and get back to work.

Mark

 

[Christopher]

But what would be generating that containment field? If the beam is made of antiprotons -- especially if it's purely an antiproton beam as the Planet-Killer's allegedly was -- then the only things that can be generating any kind of field that travels with the beam are the antiprotons themselves. And the fields they generate are the exact things that are pushing them apart in the first place. The only way to cancel that electrostatic bloom effect is to add particles of the opposite polarity to render the beam electrically neutral -- but then it isn't a pure antiproton beam anymore.

More than you ever wanted to know about the physics and engineering difficulties of particle beams:
http://www.projectrho.com/rocket/rocket3x.html#particle

And here's a section of the same page talking about why antimatter really isn't a very good weapons technology anyway:
http://www.projectrho.com/rocket/rocket3x.html#antimatter

 

[Plecostomus]

Maybe it wasn't a pure beam after all. The TOS Enterprise simply couldn't detect the exotic component of the beam that made the whole thing worthwhile.

Moving from the realm of science to utter crap now... Peter David postulated that the thing held the leftover consciousness of a dead race. Maybe the beam was held together by psychic will/psychic energy.

 

[ahkyahnan]

Christopher said:
But what would be generating that containment field? If the beam is made of antiprotons -- especially if it's purely an antiproton beam as the Planet-Killer's allegedly was -- then the only things that can be generating any kind of field that travels with the beam are the antiprotons themselves. And the fields they generate are the exact things that are pushing them apart in the first place. The only way to cancel that electrostatic bloom effect is to add particles of the opposite polarity to render the beam electrically neutral -- but then it isn't a pure antiproton beam anymore.

I thought about the "pure" remark too, and was thinking that maybe it would be assumed that a beam of that nature would have to be held together somehow, and that the pure remark might refer to the main part of the beam and not the field containing it. I don't know if that even makes sense maybe, but for example if Scotty mentioned a pod of pure anti-protons being stored in Engineering, it might go without saying that something was containing it. Of course I'm picturing the fields as not "mixing" which may be offbase.

The image I had was a tubular containment field keeping the anti-protons together inside until the beam gets close to the target, but that kind of thinking may only make sense in a universe where a pattern buffer can keep all your childhood memories from scattering apart.

Thanks for all the extra info and links by the way. I always enjoy reading your posts.

Mark

 

[Timo]

The image I had was a tubular containment field keeping the anti-protons together inside until the beam gets close to the target..

..Something that's certainly doable by the laws of physics. Just use a tubular magnet at the orifice that spits out the beam. The field thus generated won't stay tubular for a great distance, but you can always define "great" and "not great" by ramping the field strength up and down...

Essentially, the DDM could be one gigantic focusing magnetic lense for the planetkiller beam, similar to the lenses of electron microscopes.

Timo Saloniemi