Anti-matter 'news'?

[spaceranger]

Fascinating. *raises one eyebrow*

http://news.yahoo.com/s/mcclatchy/20090311/sc_mcclatchy/3186267

" NASA has identified anti-matter as the ultimate energy source for exploration of the outer reaches, and outside, of the solar system," Jackson said. ``This work is all theory to date, but we are moving quickly to the experimental stage."

 

[Eagle]

Looks like the first person to come up with a more efficient antimatter conversion process will be very rich.

There's gotta be a better production method than giant particle accelerators.

 

[tblaxland]

Looks like the first person to come up with a more efficient antimatter conversion process will be very rich.

Yep, just like the first person to come up with the first net positive energy sustainable fusion reactor. I just can't decide which to try first... :hmm:

 

[Eagle]

Yep, just like the first person to come up with the first net positive energy sustainable fusion reactor. I just can't decide which to try first... :hmm:

Realize that if you can convert matter to antimatter for less energy than the neutralization reaction its better to skip the fusion reactor and just build an antimatter reactor.

But then again ITER is being built and the Navy is currently testing the WB-7.1 Polywell. So fusion shouldn't be that far away.

 

[tblaxland]

Realize that if you can convert matter to antimatter for less energy than the neutralization reaction its better to skip the fusion reactor and just build an antimatter reactor.

Right, thanks for the tip. I gotta go to bed now, but I'll get started on it first thing in the morning

 

[RisingFury]

Unfortunately, commercial fusion power is still some time away. Although ITER will acheave a 10 times as high output as the input has to be, it's designed to keep the reaction going for only seconds... and it's goal is to find if the building of fusion power plants would be commercially possible. If fiesible, commercial fusion is still decades away.

 

[Urwumpe]

Unfortunately, commercial fusion power is still some time away. Although ITER will acheave a 10 times as high output as the input has to be, it's designed to keep the reaction going for only seconds... and it's goal is to find if the building of fusion power plants would be commercially possible. If fiesible, commercial fusion is still decades away.

Yeah, the famous difference between idea and implementation. By the ideas, we should be living on Mars now. By the implementation, we are already challenged by living in LEO.

 

[Usonian]

I wonder what the "fail-safe" is?

Plain old radioactive fuel is easy to store, in theory (and pretty much in practice). And the chain reaction can be stopped by inserting control rods. I don't know the details, but I suppose this is a simple and fairly quick motor driven process, that can be carried out with emergency generators in a pinch. Depending on the reactor design, I suppose the control rods could be arranged use gravity and simply drop into place.

Wouldn't an anti-matter magnetic bottle have to be provided with completely uninterrupted power? There would seem to be no short-term backup solution for storing a significant mass of anti-matter. Having an emergency generator running for a few minutes, or an hour, to complete a short-term, closed-end shut down process is one thing. Seems that with anti-matter the magnets must stay on or... BANG.

Well, I suppose there are a whole lot of people smarter than me working on this. After all, I don't know nothin' 'bout no eee-co-nomics. Thank goodness high finance is safely controlled by people a whole lot smarter than .... um.... hmmm.... well, damn....

 

[Dig Gil]

They could make a magnetic capsule out of anti-matter then usual permanent magnets to keep it centred. Think on how the Maglev never touches its rails (it actually uses electromagnets, but it needs to stop unlike our antimatter fuel.) no need of complicated and intense magnetic fields aboard.

 

[Radu094]

Right, thanks for the tip. I gotta go to bed now, but I'll get started on it first thing in the morning

I still have some leftover dilithium cristals in the basement. Let me know if you need it.

 

[Sky Captain]

For interplanetary travel antimatter seems a bit overkill. Fission has more than enough power to get manned missions anywhere in solar system in reasonable time. Not to mention the anti matter production breakthroughs needed to produce antimatter in a sufficient quantities to use it as a fuel.

 

[RisingFury]

For interplanetary travel antimatter seems a bit overkill. Fission has more than enough power to get manned missions anywhere in solar system in reasonable time. Not to mention the anti matter production breakthroughs needed to produce antimatter in a sufficient quantities to use it as a fuel.

Naw, I don't think it would be overkill. It would just proved better possibilities for initial propulsion for ejection of the solar system... although for long lasting voyages, something like the buzzard ramjet might be better cos it can scoop up fuel.

 

[Hielor]

... although for long lasting voyages, something like the buzzard ramjet might be better cos it can scoop up fuel.

Hehe, buzzard ramjet. Does it circle around the corpses of dead hydrogen atoms and then pick them up for food? :rofl:

 

[howitzer]

I think the most interesting thing we will discover is how antimatter reacts to gravity.

"Phillips presented a proposal to the Fermi lab last Thursday for an "anti-matter gravity experiment" to test how gravity affects anti-matter. For example, would an anti-apple fall up or down?"

If it 'falls up', then it repels. If you put a great negative mass next to a great positive mass, then you have propulsion. The masses will move together in the direction of the positive mass (as the antimatter falls into the regular matter, the antimatter repels the positive matter, creating a situation where the two masses never get any closer or any further apart - but also accelerating in a straight line.)

 

[Hielor]

If it 'falls up', then it repels. If you put a great negative mass next to a great positive mass, then you have propulsion. The masses will move together in the direction of the positive mass (as the antimatter falls into the regular matter, the antimatter repels the positive matter, creating a situation where the two masses never get any closer or any further apart - but also accelerating in a straight line.)

I'm confused as to why they would fall together if they repel each other?

 

[Tommy]

If you put a great negative mass next to a great positive mass, then you have propulsion. The masses will move together in the direction of the positive mass (as the antimatter falls into the regular matter, the antimatter repels the positive matter, creating a situation where the two masses never get any closer or any further apart - but also accelerating in a straight line.)

I don't think so. What you seem to be saying is that positive matter attracts anti-matter, but is also repelled by it. Even if this were true, there's no method of propulsion. The objects may move to a "stasis" distance relative to each other, but Newtons Laws of Motion still apply.

 

[tblaxland]

I'm confused as to why they would fall together if they repel each other?

Me too. In addition, surely if there was an acceleration, it would be along the line between the two masses. howitzer seems to be suggesting an acceleration perpendicular to that line.

Regardless, I have trouble bringing myself to believe that anti-matter would exhibit anti-gravity or some other non-normal gravitational action since it would seem in contradiction with the equivalence principle. Anti-matter particles do not seem to exhibit anti-inertia (ie, charged anti-particles behave as per normal charged particles in a magnetic field, except for the opposite charge), so why would they exhibit anti-gravity?

 

[Tommy]

I don't think he meant perpendicular, but a constant acceleration along the vector from the repulsive matter to the attractive matter. But it violates Newton's third law. It assumes that the RM is drawn toward the AM, but AM doesn't have any reaction to the attractive force moving the RM. At the same time, the AM is repulsed by the RM, and moves away, but the RM isn't affected by that force.

As for the experiment, I can see three possible outcomes.

1. The AM will drop. This means AM is attracted to M and is affected by (and in sufficient quantities can produce) gravity.

2. The AM will hover. This could indicate that AM is unaffected by gravity, or that it is in equilibrium - the forces attracting it are equal to the forces repelling it.

3. The AM will rise. This means that AM is repelled by M, and is "anti gravity". This would make a useful fuel. Fill a big ship with fuel, then unclamp it from the pad and watch it float up. Once the "Anti Gravity" forces die down you can us the AM for fuel.
There is also the possibility that AM has true Anti Gravity, that it is not only repelled my M but attracted to itself. In other words, Anti Gravity would be to Anti Matter exactly what Gravity is to Matter.

Think about it. Somewhere far, far away, in an Anti-Matter galaxy, some Anti-person on some Anti-world may be thinking about using Matter as a fuel source!

 

[tblaxland]

Anti Gravity would be to Anti Matter exactly what Gravity is to Matter.

Well, I would expect that outcome if anti-matter exhibited anti-gravity. I still consider that the equivalence principle is sufficiently well bounded by experimental evidence to rule out both 2 & 3 with a large degree of certainty. Still, you can never have enough experimental evidence, so I would look forward to any results. Probably the most important outcome would be the development of techniques to allow you to control anti-matter well enough to achieve meaningful results.

 

[Eagle]

There are going to be some difficulties in measuring gravitational attraction for antimatter. Aside from the usual 'explodes into energy' problems there's the small fact that gravity is the weakest of all forces and some unexpected or unaccounted for factors in the other forces can easily dominate.

I still hold out hope that efficient conversion is possible. The energy of an antimatter particle is the same as that of a matter particle. If you could find a way to make the antimatter state slightly lower in energy it might be possible to use quantum tunneling to help.

for those who aren't familiar quantum tunneling basically means a small subset of particles will be able to transition to a lower energy state even though there isn't enough total energy in the system to make the transition.