Anti-matter 'news'?

[Tommy]

What most people refer to as "anti-gravity", in fiction and spaceflight, is just a force repelling gravity, not "true" Anti Gravity. It's unlikely, but until proven otherwise I accept the possibility that a chunk of Anti-Matter could be repelled by Matter, but not attract other Anti-Matter.

However, the Universe (or Multi-verse) seems to like balance, so I find it likely that Anti-Matter type Anti-Gravity would be a polar opposite of Matter's Gravity.

Like you, I'm expecting the "thud" outcome.

 

[Eagle]

What most people refer to as "anti-gravity", in fiction and spaceflight, is just a force repelling gravity, not "true" Anti Gravity. It's unlikely, but until proven otherwise I accept the possibility that a chunk of Anti-Matter could be repelled by Matter, but not attract other Anti-Matter.

I think you meant Anti-Matter gravitationally attracts other anti-matter. Otherwise it would not be a true mirror to gravity.

However, I have a feeling that gravity acts normally on anti-matter. Just like the van der Waals force (electrostatic field) always attracts independent of charge.

 

[Andy44]

So, getting back to topic of using antimatter as rocket fuel, the question is, how much energy does it take to produce one joule's worth of antimatter? Is it economical to use antimatter as a fuel when it may use huge amounts of energy to make it and store it?

In the "Star Trek" universe the excuse was made that large amounts of antimatter are floating in interstellar space, and that starships collect it with some sort of Bussard ram scoop device.

But in real life there's no easy deposit of antimatter laying around; the only way we get it is to make it, right?

So you gather up enough to make a round trip to Saturn or maybe even Neptune. Cool. How many times can you do that in one year without breaking the bank?

Seems like fusion is a more credible idea, at least the fuel's readily available. And even that's still just fantasy at this point.

 

[n72.75]

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....

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.

Soooooooo, you don't store it. you make it as you go. obvously you would need to store some to act like a buffer, plus you would need it to start the reactor.

I guess the only problem is finding a spare hundred or so Kg.

I have some, you can have it, I dont use it much except for toilet cleaner.

 

[Notebook]

http://news.bbc.co.uk/1/hi/sci/tech/7977102.stm

Maybe the anti-matter drive has been built...

N.