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Not only did they wash away 22 years ago. They washed away because the islands used to be covered in a forest of mangrove trees which were completely clear cut away to provide a place for human settlement as they had been uninhabited before. Then, golly gee, after all the trees on a sand bar in a river delta were cut away, the sand bar suffered major erosion over the next few decades and is now no longer above water. THIS HAS NOTHING TO DO WITH GLOBAL WARMING AND RISING SEAS. It is an ecological problem, but to blame it on CO2 emissions is to totally miss the point. The problem here was loss of forest, loss of vegetation, overpopulation, and clear-cutting instead of proper management of the flora. Even if the earth were cooling and the seas were falling, and given the same ecological problems in the area, THIS island would have disappeared anyway.

An external neutron source allows you to initate the chain reaction when the conditions in the fissile core are ideal for fission (the neutron multiplication rate [alpha] is at a maximum) and avoid predetonation, where the core initiates and blows itself apart before maximum alpha is achieved and consequently yields less than it should. It's a way of insuring the bombs work right every time, and making the most efficent use of your fissile material - but minimum critical mass is a mathematical function of the material.

See The Nuclear Weapons Archive, Engineering and Design of Nuclear Weapons for (lots and lots) more info. Brush up on your particle physics first though, it's a hefty read :)

Incidentally, you could theoretically use U-235, Pu-238, Pa-231 [>188kg], Np-237 [~90kg], Am-241 [84 kg], Am-234 [140kg], Cf-249 [5.9kg], Cf-251 [1.94kg], or Cf-252 [2.73kg] for a fission bomb, but only U and Pu are practical.

An external neutron source allows you to initate the chain reaction when the conditions in the fissile core are ideal for fission (the neutron multiplication rate [alpha] is at a maximum) and avoid predetonation, where the core initiates and blows itself apart before maximum alpha is achieved and consequently yields less than it should. It's a way of insuring the bombs work right every time, and making the most efficent use of your fissile material - but minimum critical mass is a mathematical function of the material.

See The Nuclear Weapons Archive, Engineering and Design of Nuclear Weapons for (lots and lots) more info. Brush up on your particle physics first though, it's a hefty read :)

Incidentally, you could theoretically use U-235, Pu-238, Pa-231 [>188kg], Np-237 [~90kg], Am-241 [84 kg], Am-234 [140kg], Cf-249 [5.9kg], Cf-251 [1.94kg], or Cf-252 [2.73kg] for a fission bomb, but only U and Pu are practical.

Although plutonium presumably exhibits chemical toxicity like other heavy metals, this effect is insignificant (in fact, unobservable) compared to its radiotoxicity. Plutonium's toxic properties are due to the fact that it is an active alpha emitter. Alpha particles are hazardous only if they are emitted inside the body (i.e. the plutonium has been ingested).
...
Swallowing 500 mg (7 curies) of plutonium as a finely divided or soluble material can cause death from the acute exposure of the GI tract in several days to a few weeks. Inhalation of 100 mg (1.4 Ci) of plutonium as particles of optimal size for lung retention can cause death from lung edema in 1 to 10 days. An inhaled dose of 20 mg (0.28 Ci) will cause death by fibrosis in about 1 month. In doses much below these values, the chronic carcinogenic effects become the important ones.

My other source

You description is almost correct, but not quite. Rather than use a *HUGE* third stage which used about 2 tonnes of Lithium Deutride, they split it up into several capsules, each with about 10-20Mt worth of lithium deutride. Only the fuel used for the thermonuclear third stage.

Think of it as trying to break a rock with a cold chisel. What will work better? Hitting it once hard enough to break it apart, or hitting it lots of times, but with about a 40th of the force? Even if the smaller bombs are more efficient, they aren't going to be able to put a huge amount of energy into one point.

while never publically admitting it, it's common knowledge that israel is a nuclear state (with our help, of course), with 50-200 boosted fission bombs (~2-400kT yield).
now - if we just drop israel and "let that problem sort itself out", how long do you think it would take for them to decide that their very existence is in mortal danger and use that as a convenient, as-near-to-morally-justifiable-as-possible excuse for unleashing the fires of hell on the surrounding countries? i don't agree with what israel is doing and i think they do need a firm slap, but just ditching them would be one of the worst things we could do.

The government looked in to how hard it would be for people to cull together a working nuclear weapon design from available information years ago.

"Interestingly enough, the United States government conducted a controlled experiment called the Nth Country Experiment to see how much effort was actually required to develop a viable fission weapon design starting from nothing. In this experiment, which ended on 10 April 1967, three newly graduated physics students were given the task of developing a detailed weapon design using only public domain information. The project reached a successful conclusion, that is, they did develop a viable design (detailed in the classified report UCRL-50248) after expending only three man-years of effort over two and a half calendar years. In the years since, much more information has entered the public domain so that the level of effort required has obviously dropped further."

From The Nuclear Weapon Archive: a Guide to Nuclear Weapons

That was back in 1967, a bit more than thirty-six years ago. It probably takes a lot less digging nowadays.

You forget that "the number one terrorist state" you hate so much happens to be sittng on 7,339 nuclear warheads with a total yield of over two thousand eight hundred megatons. I'm guessing you're hoping and praying for a crude nuclear strike on NYC - you and your friends try that, and I assure you everything between Israel and India, from Egypt to Turkey, will be vaporized. You obviously understand the strength of violence, so why do you promote the use of it against a nation that has both the means and the determination to retaliate a hundred times over? Oderint dum metuant.

I would have thought that banks would have taken every precaution necessary to isolate their ATMs from Internet based attacks, but it seems that it is not so. Dedicated lines or not, they are still vulnerable.

Last January 3 major Canadian and 1 US banks' ATMs were disrupted disrupted by the Slammer worm

I know from personal experience that my bank (CIBC) runs NT/W2K on their ATMs. I've see it reboot, BSODS and Windows 'Start' screens on various ATMs.

It actually is pretty hard to make an implosion-type bomb work. They didn't work out the designs using slide rules, but actually cobbled together what was a hell of a lot of computing power for the day. I don't remember if they actually built any general-purpose electronic computers, but at least some of the work was done by large teams of workers using single purpose calculating machines. One machine would could add, another multiply, etc. and the system was "programmed" by coming up with a specific order in which IBM cards containing the information being processed were run through the system. Richard Feynman discussed a lot about this system in "Surely You're Joking, Mr. Feynman!". Admittedly the average mobile phone these days probably had enough processing power to do those calculations, but the Nobel Prize winning minds in charge of the project had a lot more to do with its success than the raw processing power.

FWIW, you can learn far more than you ever wanted to know about nuclear weapons by reading the Nuclear Weapons Archive. When you understand everything in there, you can start thinking about building bombs.

The High Energy Weapons Archive has a good rundown of neutron bombs. They're a bit more complicated than just taking the jacket off a hydrogen bomb (still needs the jacket to get the fusion going) - see the FAQ for a rundown. The Mk 70-0 nuclear artillery shell was apparently a tactical neutron device (~1kT yield); I dont know if it was ever tested. I wouldn't really call a staged implosion H-bomb a Rube Goldberg device, though..its a bit more complicated than you paint it to be; the tolerances are on the order of a few microns and nanoseconds. See the rest of the FAQ for a hugely in-depth discussion of the physical principles and engineering that goes into one of these things (you need a grasp of thermodynamics and physics, though).

I suspect that these bombers will have conventional as well as nuclear capacity - a 475Kt W-88 is one hell of a shock and awe weapon, but it's not exactly useful for limited strikes, or anything short of total global devastation...

A-bombs are fucking simple. Get n amount of fissionable material. (n depends on what type) Wrap it in plastic explosive. Detonate to compress, achieve critical density, and set off the explosion.

Which is why the Nuclear Weapons FAQ runs to book size to explain the engineering and physics required. Sure.

Why doesn't anyone bother with research anymore?

all nukes are detonated in the air, in stead of on the ground, to maximize the damage. this was done with the relatively small (~15-20kt) bombs dropped on hiroshima and nagasaki, and would also be true for larger bombs.
so, except for maybe tactical nukes for very specific purposes (targetting some structure directly, maybe) all nukes are detonated in the air above their target. a 50Mt bomb would have to be dropped a little higher than a 20kt one, but it's still the same...and it'd CERTAINLY be "useable against ground targest", it just isn't detonated on the ground.

maximizing EMP damage is something different. to this the bomb would be detonated at *very* high altitudes (above 30,000 m). then the ground damage will of course be minimized, but it's not because the bomb can't be used against a ground target in a "normal" way.

check out this link for a good explanation of nuke effects, including EMP (section 5.5)

"funny you should mention that because there's this little thing in physics called pair production and it deals with quarks, and wait, get this, they spontaneously pop into existence, isn't that a bitch. and its been observed too, so i guess something can be produced from nothing.
a bugg"

Nice knowledge, but you should know from whence it comes. Law of conservation of energy states (yes, LAW) that nothing can come from nothing. What you are speaking of is matter coming from energy. Yes, e=mc^2, and all that, states that matter and energy are interchangeable. Ahh yes, the answer to the great question of philosophers over the ages, "Where does fat go when I burn it?" The opposite, as you have stated, also occurs, and has been proven; i.e. an object, when energy is added, gains mass. *tangent* This is even true for POTENTIAL ENERGY! How cool is this: A spring, when compressed, weighs more!!! (Link, Page 10)

While energy converting to matter may put off heat death a little while longer, it's no great epiphany :)

A quick Google for electric pickle turns up some pictures and even movies here.

Along the same lines as the eletric pickle (but totally irrelevant to the rest of the topic), there's always the sparking grape trick.

-l

In this interview with the President of the RIAA he spouts the party line.

Eric Olsen: How are you actually going to overcome the "fair use" doctrine? It's already a fact that "archival" copies are allowed, so why is "space shifting" not archival and thus "fair use"?

Cary Sherman: ... It is not a fact that "archival" copies are allowed. Copyright law specifically allows certain kinds of archival copies of software, but not of music, movies, books or anything else. In fact, in the Texaco case, the court held that making archival copies of scientific papers was not a fair use. As for space shifting, I don't think any court has actually held that it's a fair use. And a couple have specifically ruled that it isn't.

Now compare and contrast with Orrin Hatch questioning Hilary Rosen in the Senate- here:

''Can I make a copy of a CD that I buy and put it into a car?'' asked Hatch. When Rosen hemmed and hawed, Hatch muttered, ''The answer is yes.''

If china wanted to attack the USA [or anywhere else] then they'd send out some email viruses. There's more than enough dumbasses on the net that would open it up and unwittingly launch the attacks on China's behalf. Carnivore could be used to filter them, if they [guvverment] tried.

OTOH, direct packet attacks are a different kettle of fish. The only glimmer of hope is that the NSA [or other three-letter-agency] had Cisco equipment riddled with backdoors, just like MS Software. Hell, well all know they've done worse...

Ali