Antimatter question

[NobbyNobbs]

I briefly considered posting this under the Conspiracy forum, but the core of my question is pure science, so here it stays.

One of the CT theories about the destruction of the WTC involves the use of an antimatter weapon. I didn't know too much about antimatter, but the Wikipedia article is fairly well written. From that, I found out...

This means to produce 1 gram of antimatter, CERN would need to spend 100 quadrillion dollars and run the antimatter factory for 100 billion years. Storage is another problem, as antiprotons are negatively charged and repel against each other, so that they cannot be concentrated in a small volume.

What I haven't found any reference to is a clear idea of how useful this much antimatter would be. Could it power a light bulb for a minute? Could it power the entire U.S. for a decade? Something in between?

If there are any particle physicists out there with the ability to answer this, I'd appreciate it.

And if you'd like to answer the extra credit question as well, how much antimatter would it take to "dustify 80% of the steel", as some CTers are claiming happened?

 

[Hellbound]

From some of my earlier research (which may have been incorrect, or I may be misremembering), a microgram of antimatter, assuming you could get the entire energy of the reaction, would power a 100W bulb for something like 1000 years.

I'll work on the calculations, and see what I come up with

 

[Hellbound]

E = mc²
E = (.002kg)*(299,792,458 m/s)² (Note, I used double the mass becuase you also convert whatever normal matter the anitmatter interacts with)

E = 179,751,035,747,363.528 kgm²/s²or
179,751,035,747,363.528 Nm

1 watt=1 Joule/second, 1 Joule = 1 Newton-meter

So, 179,751,035,747,363.528 J / 100 J/s gives time in seconds for a 100W lightbulb.

1,797,510,357,473.63528 s

Divide by 60
29958505957.893921333333333333333 minutes

Divide by 60
499308432.63156535555555555555556 hours

Divide by 24
20804518.026315223148148148148148 days

Divide by 365
56998.679524151296296296296296296 years.

So a gram will run a hundred watt lightbulb for 57,000 years, assuming 100% efficiency.

 

[Cuddles]

E = mc². 1 gram of antimatter would give out 1.8*10¹⁴ Joules when it anhiliated with 1 gram of matter. According to Wiki, 1 kilton of TNT equivalent is 4.184*10¹²J, so the antimatter would be about 40 kilotons. Equivalent to a fairly small nuclear weapon, bigger than those dropped in WWII (about 20kT), but much smaller than any that exist now (~100kT up to ~50MT).

That's enough to power a lightbulb for about 60,000 years, or about 2000 average US homes for a year. I don't know about dustification, but I imagine that would be enough to take out a couple of buildings. And probably any other buildings within a couple of miles.

Edit : Damn Huntsman's fast typing.

 

[Hellbound]

Hahah! The fast typer strikes again!

Nice to see someone back up my calculations, though. Replicaition is one of the keys to science, after all

However, I believe about 50% of the matter-anti-matter reaction energy goes into gamma rays (I may be mis-remembering this as well), which are hard to capture for energy production. Also, very few energy capture methods for something like this would be very efficient. I think you could expect an efficiency rating similar to an IC engine or a steam plant for the part of the reaction that is blast/heat. So overall, I'd expect current energy production based on antimatter to actually be able to use about 25% of the energy (ballpark figure).

But, then again, you have to figure the energy that goes into making the antimatter, and the energy used in the containment fields and systems (which must be magnetic fields in a vaccum...ANY contact with ANY normal matter and it all goes boom...don't build an anti-matter plant near my house, please). Realistically, I'd expect antimatter energy to be a net loss, and it is when the energy to make it is figured in. However, the advantage comes form it's amazing compactness and energy density. It wouldn't be so good for power production, but would be excellent as spacecraft fuel.

 

[Ocelot]

Amazing a silly idea from fiction adopted by conspiracy theorists. What wuold they have done if Dan Browne had been bale to explain all that hard science for them.

http://public.web.cern.ch/Public/Content/Chapters/Spotlight/SpotlightAandD-en.html

Strange Similarities to the way that nobody doubted the moon landings until Capricorn 1 came out.

 

[NobbyNobbs]

I seem to remember the article mentioning a loss of energy due to the production of neutrinos (?), but I wanted to give the argument the best benefit of the doubt. That is, I wanted to assume

a) The process to create the antimatter was nearly perfectly efficient
b) The reaction to release the energy was 100%
c) We have the technology to create enough to do the job

Assuming the above, I wanted to find out what it would take in terms of time, money, and ability (to create the antimatter). I think you've confirmed my suspicions very well. Thanks!

 

[kalen]

There isn't nearly enough significant digits in Huntsman's calculations.

 

[kalen]

However, I believe about 50% of the matter-anti-matter reaction energy goes into gamma rays (I may be mis-remembering this as well), ...

Alot of the radiation would be gammas. Which means that if a matter---anti-matter weapon was really used, everyone close to the WTC would receive a fairly hefty dose. Given the 1 gram of antimatter scenario, from 200 m away, a person would receive roughly the equivalent of a billion chest x-rays.

 

[fuelair]

Alot of the radiation would be gammas. Which means that if a matter---anti-matter weapon was really used, everyone close to the WTC would receive a fairly hefty dose. Given the 1 gram of antimatter scenario, from 200 m away, a person would receive roughly the equivalent of a billion chest x-rays.

That would mean an awfully large number of people near GZ with, like, major cancer or already dead!

 

[Fnord]

[FARCE]

How do you "prove" a conspiracy? It's simple, really...

1) Claim that the conspiracy exists.
2) Claim the use of methods and/or substances that would be impossible to carry out and or produce.
3) Claim that the lack of factual evidence for the existance of the methods and/or substances is due to a conspiracy, and...

Voila! Conspiracy is "proven."

Now, as far as anti-matter is concerned, the fact that most of the bodies were disintegrated also "proves" that anti-matter was used, since the gamma-ray burst would have instantly disintegrated the victims.

[/FARCE]

It's just too freekin easy to think of this kinda crap! No wonder ignoramuses believe it!

 

[Cuddles]

Hahah! The fast typer strikes again!

Nice to see someone back up my calculations, though. Replicaition is one of the keys to science, after all

However, I believe about 50% of the matter-anti-matter reaction energy goes into gamma rays (I may be mis-remembering this as well), which are hard to capture for energy production. Also, very few energy capture methods for something like this would be very efficient. I think you could expect an efficiency rating similar to an IC engine or a steam plant for the part of the reaction that is blast/heat. So overall, I'd expect current energy production based on antimatter to actually be able to use about 25% of the energy (ballpark figure).

You could capture almost all the energy from an antimatter reaction using the same sort of design as in particle detectors in accelerators. They only miss the neutrinos which would only account for a tiny fraction of the energy. From the conspiracy point of view I don't think the efficiency matters too much. If you're trying to demolish one building then 40 kilotons or 10 kilotons isn't really a huge difference.

But, then again, you have to figure the energy that goes into making the antimatter, and the energy used in the containment fields and systems (which must be magnetic fields in a vaccum...ANY contact with ANY normal matter and it all goes boom...don't build an anti-matter plant near my house, please). Realistically, I'd expect antimatter energy to be a net loss, and it is when the energy to make it is figured in. However, the advantage comes form it's amazing compactness and energy density. It wouldn't be so good for power production, but would be excellent as spacecraft fuel.

Yes, antimatter is the futuristic hydrogen. Or at least it will be once hydrogen stops being the futuristic hydrogen. If you have to produce something before you can use it, it can never be used to get a net energy gain. However, as a battery there is nothing that could ever be more efficient at storing energy, although containment issues would reduce the efficiency somewhat.

 

[wahrheit]

snip

However, as a battery there is nothing that could ever be more efficient at storing energy, although containment issues would reduce the efficiency somewhat.

I truly hope that containment issue will be solved by then. I don't want to know what my head looks like after my brand new antimatter-driven cell phone went off.

 

[Jimbo07]

I don't follow the CT threads so I didn't know they were this bizarre! I don't buy, but at least I was okay with, something like George W. Bush/Halliburton/the Axis of Evil deliberately blew up the buildings with conventional bombs, TNT, whatever...

but antimatter weapons?!?

What is wrong with people?

 

[RenaissanceBiker]

What is wrong with people?

Almost half of them have below average intelligence.

 

[Jimbo07]

Almost half of them have below average intelligence.

Yeah! That's it! And the other two thirds have... wait...

 

[Hellbound]

You could capture almost all the energy from an antimatter reaction using the same sort of design as in particle detectors in accelerators. They only miss the neutrinos which would only account for a tiny fraction of the energy. From the conspiracy point of view I don't think the efficiency matters too much. If you're trying to demolish one building then 40 kilotons or 10 kilotons isn't really a huge difference.

Well, I was thinking more in terms of powering a light bulb

But talking about capturing the energy, would all that be useable energy? Something we could turn to electricity? I was thinking that the most likely design would be some sort of magnetic piston type arrangement or (more likely) using the released thermal energy for a steam operation (much like nuclear). You seem to be talking of something different...maybe a process similar to RTGs? I don't know enough about the specifics to make a good estimate on that

 

[RecoveringYuppy]

And if you'd like to answer the extra credit question as well, how much antimatter would it take to "dustify 80% of the steel", as some CTers are claiming happened?

Do those CT theories specifically say anti-protons? The gamma rays from a proton/anti-proton reactions are going to be extremely penetrating. There'd be no way to confine their area of affect soley to the steel. I doubt there's enough mass in all the buildings of New York to even confine the area of effect to New York. I'm not an expert but I think it's pretty safe to say that if there were anti-proton reactions inside those buildings most of the energy from those reactions would have left the building and done damage elsewhere (or left the planet, or absorbed on it's way through the Earth).

ETA: It occurs to me that the CT probably also claims that depleted uranium was used to shield the gamma rays.

 

[Cuddles]

Well, I was thinking more in terms of powering a light bulb

Hmm, a 40 kiloton lightbulb. There must be some kind of world record there somewhere.

But talking about capturing the energy, would all that be useable energy? Something we could turn to electricity? I was thinking that the most likely design would be some sort of magnetic piston type arrangement or (more likely) using the released thermal energy for a steam operation (much like nuclear). You seem to be talking of something different...maybe a process similar to RTGs? I don't know enough about the specifics to make a good estimate on that

No, I don't think it would be useable, except through standard ways of harnessing the heat produced, such as steam turbines or thermocouples. I just mentioned particle detectors to point out that it is possible to capture virtually all particles, even if we can't necessarily do anything with them. The problem is that in order to stop high energy particles the detectors must be very large and dense, so it would be almost impossible to do anything with the energy collected before it just became dispersed as heat.

Almost half of them have below average intelligence.

Interestingly, a lot more people have below average intelligence than above, because the distribution is not actually a Gaussian. Many people have slightly below average IQ, say around 90, but this is balanced by a few having much higher, say 130 (numbers made up by me). So for every three people below average, only one is needed above to keep the average the same. If you think about the extreme cases this is actually just common sense. It is impossible to have a negative IQ, so either 0 or 1 must be the lowest score possible, but it is possible to have over 200.

I don't follow the CT threads so I didn't know they were this bizarre! I don't buy, but at least I was okay with, something like George W. Bush/Halliburton/the Axis of Evil deliberately blew up the buildings with conventional bombs, TNT, whatever...

but antimatter weapons?!?

What is wrong with people?

Antimatter weapons bizzare? Just wait until you here about the space-based satellite death beams. Or fairies.

 

[Schneibster]

I can confirm the figures given (21kt/gm) (remember, you have one gram of antimatter, that annihilates 1 gram of matter, that's two grams) due to numerous times calculating it.

I think that people think about the WTC and think the buildings were really big. They tend not to thing about things like the city of Hiroshima was really way bigger. You can't disintegrate steel beams inside a building with antimatter and have it not affect the concrete around them, even if you forget about the energy the matter and antimatter get converted into.

By and large, the emissions from annihilation are gamma rays; even an electron/positron annihilation gives off pretty hard gamma, so what will a proton/antiproton annihilation do remembering that protons are 1830 times more massive than electrons? We're talking about some very heavy-duty gamma rays here. I mean muscular, capable of ripping atoms apart as they pass through them. Absorbing that energy and using it for anything is a very difficult problem, and you don't want it bouncing around anywhere anyone lives, either.

As a power source, I think antimatter is well beyond our reach. Maybe not later, but I seriously doubt there will be annihilation plants in the middle of cities, or even anywhere near a planet we care anything about.