

Is fusion success in sight?  - edw519
http://cosmiclog.msnbc.msn.com/archive/2010/01/28/2187974.aspx

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NathanKP
I thought one of the statements in the article was especially interesting:

 _"NIF isn't truly about energy," Seife writes in his book. "It is not about
keeping our stockpile safe, at least not directly. It is about keeping the
United States' weapons community going in the absence of nuclear tests."_

That's obviously a pretty pessimistic point of view, but when I consider the
details of the test, including the immense amount of energy required to fire
the lasers ten times a second, as would be required to start it according to
the article, I don't see how it would be possible to get that much power back
out, at least not using the traditional water to steam technique.

~~~
electromagnetic
Essentially if they can make the equipment small enough, there could be
serious potential for a pure-fusion bomb, which could skirt the test ban
treaty as it doesn't fall under the terminology of a nuclear weapon (fissile
or fissile and fusion; pure fusion isn't in the CTBT terminology, IIRC).

Although the Ares 1 under development is currently capable of putting 25,000KG
into LEO, and the Ares V is expected to be capable of up to 188,000KG. So it's
not like the equipment has to be exceptionally small if it's capable of
producing pure-fusion, it just has to be slightly smaller than the ISS!

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jroes
Aren't encryption algorithms measured by the amount of computing power it
would take to crack them? If so, given a limitless power source, we could be
in for some real privacy trouble, correct?

~~~
jerf
I do not know if you're being funny or not, because there is indeed a study of
the minimum raw energy requirements for a given computation in our
universe[1], so it is technically possible to rate the amount of computation
something requires in terms of joules or your choice of energy unit. So I
don't know if you know of this and are confused, or if you're trying to make a
bad joke/pun on "power" (seems to be lolcraft's theory). Since there is a
serious angle to your post, deliberate or otherwise, a serious answer:

Because encryption difficulties tend to scale exponentially as you add bits,
it is relatively easy to make encryption that brute forcing would require more
energy than exists in the known universe. As big as the Universe is,
exponential is "bigger".

That's why even now the real problem is algorithms that have something far
more clever than "brute force" available; we could already guarantee that even
a post-Singularity adversary can't brute force our encryption (assuming they
don't get new physics to play with), what we can't guarantee is that such an
intelligence couldn't find a far more practical attack.

[1]: <http://en.wikipedia.org/wiki/Limits_to_computation>

~~~
snissn
maybe he read the singularity is near too many times while stoned?

------
CWuestefeld
Summary: researchers are hopeful of achieving break-even in a controlled
fusion reaction this year, based on extrapolations of small-scale experiments.
But it's still a long way from an actually commercially-viable process, and
there are other approaches that may be more successful -- or none at all.

~~~
stcredzero
The Inertial Containment folks are going to go for exciting a hohlraum with
their 192 lasers. I don't think blasting a precisely machined gold-plated
metal cylinder every second is going to be economically viable.

~~~
mattheww
If they can reach create a controlled fusion reaction, a commercial reactor
would be designed to continually feed fuel into it to continue the reaction.
Reaching "break-even" is when the lasers don't have to be fired for the
reaction to continue.

~~~
CWuestefeld
_Reaching "break-even" is when the lasers don't have to be fired for the
reaction to continue_

No, that's a "self-sustaining" reaction. Break-even means that the amount of
energy released in the reaction is equal to the energy necessary to fuel the
reaction.

