An atomic rifle grenade would be physically impossible, since the minimum critical mass for pure weapons grade material is on the order of ~10 kg.
Historic bomb material like Pu-239 and U-235 aren't the only fissile (or even fissionable) isotopes out there, some of the others (most artificial) have quite significantly smaller critical mass. (On the other hand, they also have relatively short half-lives which make them less than ideal for practical munitions - but they may well have been used in experimental devices.)
And the mass you quote is for a simple sphere, ignoring things like neutron reflectors, compression, and exotic triggering mechanisms.
You left out, at the very least (ie, non paradigm-shifting):
4. Prolonged fission reactions in large bodies of uranium ore (see Oklo) 5. Atmospheric interaction with cosmic rays (see, eg, carbon-14)
We also know that there's always a finite, if small, probability that any two nuclei in reasonable close proximity can interact, it's just so unlikely as to not be worth bothering about. But in the solid or liquid state, nuclei are on average a lot closer together than in the plasma state; normally still considered too far apart to interact -- but the electrical fields at sub-nanometer scales in complex solids/liquids (like plants) don't lend themselves to easy computation of exactly what goes on. I'm rather skeptical of the claim about transmutation in plants myself (I saw something about it recently, but don't recall the details) but I'm unwilling to state categorically that it can't happen. I do doubt that if it does, it plays any signifant part in the plant's metabolism.
Still, with discoveries like the recent one that peeling tape off the roll can generate x-rays, who knows what high-energy but small-scale events might take place that we just haven't noticed yet.
at least one guy is saying this may be a low-temperature nuclear effect but not cold fusion.
It sounds like he might be in denial -- did he previously have a stake in the "cold-fusion is impossible" camp? Unless he's suggesting that it's cold fission, what else is there?
Cold Fusion is real, and it is science, and it is not quite repeatable yet from lab to lab, tho getting better.
So it's more like alchemy than science.
It just means we don't understand all the factors involved in repeating it. Semiconductor-based electronics have been around almost as long as vacuum tubes, but back in the pre-forties they didn't have a good grasp of, say, what made one galena crystal or copper-oxide rectifier work and another not. It took a while before the technology was up to making pure enough germanium or silicon to produce reliable components (and even now, there's something of an art to getting a fab up and running).
It may be that cold fusion effects are dependent on the microcrystalline structure of the e.g. palladium, but without knowing exactly how to reproduce that (or what exactly to reproduce), lab results will differ from one lab to another. It's not at all uncommon for a lab attempting to "duplicate" a result to actually follow some different steps, depending on what equipment and materials they have handy, especially if nobody quite realizes yet how critical some of those steps might be.
The fusion of a deuterium and tritium nucleus requires that the 56 kev barrier be overcome. Imagine how good you'd have to be to cause these nuclei to bypass that barrier entirely at very low energy conditions. It's equivalent to claiming that you can ignite paper in cryogenic temperatures using a suitable catalyst. I just don't think it is very likely given what needs to be overcome.
You might want to look up "muon catalyzed fusion". Yeah, there's a 56kev barrier (for D-T, and whatever it is for D-D) to overcome for fast-moving tritons and deuterons. There are other ways to get those particles close enough that their probable locations overlap and they fuse, it's just a matter of reducing the local strength of their repulsive electric field by countering it with opposite charge (as with a muon). Problem with that is, muons don't last very long. There may, may, be other ways to do it, and matter in the solid state has rather different properties from plasmas.
And there's the rub... if cold fusion is "COLD", then how do we utilize the energy?
Poor choice of words. "Condensed matter fusion" might be more accurate (assuming there's any fusion at all, of course). It's only cold relative to plasma-state fusion, if it generates heat enough to boil water it can produce power, and yet still be called "cold".
On the other hand, if it generates cold, we could use it for refrigerators;-)
Anonymous Bob - if you did vote libertarian all you did was help elect Obama
That's what the Republicans want you to believe. The fact is that the only thing that helped elect Obama was votes for Obama. There are plenty of issues (more social than economic) where voters might lean Democratic rather than Republican and might end up voting Libertarian because they can't stomach Democratic economic policy, just as they might favor Republicans on economic issues (or might have pre-Bush) but can't stomach their stand on some social issues.
Re:If you didn't vote libertarian, you ASKED FOR T
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Obama DOJ Sides With RIAA
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· Score: 2, Insightful
Show me a libertarian who has a snowball's chance in hell of winning, and I'll vote for him.
Substitute any third party for 'libertarian' above and your statement makes just as little sense.
What's the point of voting for someone who is going to win anyway? Might as well just stay home. Of course, the two major parties would have you believe that if you don't vote for a major party candidate, you're just "wasting your vote" -- which is utter bullshit. You're only wasting your vote if you vote for someone who doesn't support the policies you believe in. Yeah, your guy may not get elected, but at least you did your bit -- and if enough other people feel the same way you do (including rejecting the nonense about "wasting votes"), then your guy might actually make it.
Or at least put a big enough dent in the major parties' vote numbers to make them reconsider their policies.
Well, beyond a certain point, no. But an $80 "Rolex" copy isn't anywhere near that point (especially since it's guts are probably those of a $10 watch). If you really need an accurate timepiece that can stand up to the rigors that Rolexes, Omegas, etc are designed for (eg you're a diver, or a pilot, or otherwise venture where wear-and-tear will destroy that $10 watch in no time), then you'll have to pay a bit more.
But not $8000 -- a $300 Seiko (for example) will probably do about as well.
Yep, I posted below about DansGuardian. Wonderful tool.
It doesn't take much in the way of resources -- I have it (and Squid proxy) running on an old Pentium-166 with a mere 96MB RAM (and SuSE 9.3). Wouldn't surprise me if you could run it on a linux-based router.
Sure, the "best" (qualitatively) filter is to watch over your kid's shoulder -- but with three kids (each with their own computer) and other things that need doing around the house, that's not always possible.
One thing I might want (and I haven't even looked to see if it's possible) is a way to tailor the filtering to different IPs, so that for example my teenager gets a somewhat more relaxed set of rules than my two pre-teens. I suppose I could always run multiple instances on different ports, with the firewall redirecting as appropriate.
I use DansGuardian. Easy to configure and works fine (I use it conjunction with squidproxy, both running on the firewall between the DMZ and inside the house).
Occasionally I'll go in and configure it to block Flash (except for certain sites, like the kids' schools) to discourage playing flash games when they should be doing homework. If one really wanted, one could configure a cron script to modify the configs at different times of the day (I don't think dansguardian config files are smart enough to do that themselves), but I haven't bothered.
Since only the kids' computers go through DG, (that's in the firewall config) if I want to cut them off from the internet in a hurry I can just kill that, leaving the rest of the computers on the net.
I don't know about other filters -- I tried DG first and it was Good Enough -- but if they do try to hit a blocked site it will pop up a page (configurable) telling them to ask Daddy if it's something they really need access to.
OTOH, by the time you reach my age, there aren't that many totally new situations.
Or perhaps you've learned to anticipate and avoid them.
Still, there's something to be said for gaining a lot of different experiences early on, so that indeed totally new situations are rarer. That's something I did, although not necessarily with that end in mind.
So yea, youth and energy are nice, but they fade as experience comes to the fore
Yep, old age and treachery will beat youth and skill every time.
More seriously, it's faster and more efficient to retrieve a problem solution from memory than to solve it from first principles -- heck, with sufficient experience you recognize incipient problems before they start -- so as long as the RAM holds out it doesn't matter if the CPU speed starts to slip.
Of course that doesn't apply to adapting to totally new situations, something that youth has long known to be better at on average.
Converting coal to a "cleaner form of energy" just means you're taking the "dirty" parts out before it gets to the end user -- you still need to dispose of the crud, like mercury, arsenic, thorium, radon, sulfur, complex carbon compounds that don't easily convert to your fuel du jour, etc. And burning that fuel du jour still produces CO2.
Coal waste is far more toxic per watt produced than any other means of energy production, including nuclear.
Indeed, never mind the things like arsenic (that remain toxic forever) that are in coal ash.
The fact is, if coal plants had to meet the same standards for radioactive release that nuclear plants do, they'd all have to be shut down. There's all kinds of radioactive stuff in coal (radon, thorium, etc) -- not very much per ton, but coal plants burn millions of tons of the stuff. Indeed, if you could extract the thorium from coal you'd get more energy burning it in a reactor than you would from burning the carbon in a furnace. (Don't take my word, look it up.)
The Microsoft v Tom-Tom suit covers a half-dozen or so patents, only two of them FAT-related. (Besides which, the FAT patent has been thrown out in Germany.) Most if not all of them are obvious or have prior art, like the FAT patents, and may well not hold up under Bilski. What does it gain Tom-Tom to license a (potential invalidatable) patent like FAT if they're still being sued over half a dozen others? If they have to go to court anyway, might as well try to get them all overturned - they can always offer to settle later.
I haven't watched broadcast TV in years (well, maybe a couple of times). I'll happily wait a year for episodes of the few shows worth watching to come out on DVD, then I can watch what I want to watch when I want to -- no commercials, no preemptions, and if I want to watch four episodes of, say, Lost or a double episode of Dr. Who back-to-back, I can.
(And yeah, I know I could probably find the stuff online before it comes out on DVD, but that has its own set of headaches.)
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An atomic rifle grenade would be physically impossible, since the minimum critical mass for pure weapons grade material is on the order of ~10 kg.
Historic bomb material like Pu-239 and U-235 aren't the only fissile (or even fissionable) isotopes out there, some of the others (most artificial) have quite significantly smaller critical mass. (On the other hand, they also have relatively short half-lives which make them less than ideal for practical munitions - but they may well have been used in experimental devices.)
And the mass you quote is for a simple sphere, ignoring things like neutron reflectors, compression, and exotic triggering mechanisms.
You left out, at the very least (ie, non paradigm-shifting):
4. Prolonged fission reactions in large bodies of uranium ore (see Oklo)
5. Atmospheric interaction with cosmic rays (see, eg, carbon-14)
We also know that there's always a finite, if small, probability that any two nuclei in reasonable close proximity can interact, it's just so unlikely as to not be worth bothering about. But in the solid or liquid state, nuclei are on average a lot closer together than in the plasma state; normally still considered too far apart to interact -- but the electrical fields at sub-nanometer scales in complex solids/liquids (like plants) don't lend themselves to easy computation of exactly what goes on. I'm rather skeptical of the claim about transmutation in plants myself (I saw something about it recently, but don't recall the details) but I'm unwilling to state categorically that it can't happen. I do doubt that if it does, it plays any signifant part in the plant's metabolism.
Still, with discoveries like the recent one that peeling tape off the roll can generate x-rays, who knows what high-energy but small-scale events might take place that we just haven't noticed yet.
at least one guy is saying this may be a low-temperature nuclear effect but not cold fusion.
It sounds like he might be in denial -- did he previously have a stake in the "cold-fusion is impossible" camp? Unless he's suggesting that it's cold fission, what else is there?
Cold Fusion is real, and it is science, and it is not quite repeatable yet from lab to lab, tho getting better.
So it's more like alchemy than science.
It just means we don't understand all the factors involved in repeating it. Semiconductor-based electronics have been around almost as long as vacuum tubes, but back in the pre-forties they didn't have a good grasp of, say, what made one galena crystal or copper-oxide rectifier work and another not. It took a while before the technology was up to making pure enough germanium or silicon to produce reliable components (and even now, there's something of an art to getting a fab up and running).
It may be that cold fusion effects are dependent on the microcrystalline structure of the e.g. palladium, but without knowing exactly how to reproduce that (or what exactly to reproduce), lab results will differ from one lab to another. It's not at all uncommon for a lab attempting to "duplicate" a result to actually follow some different steps, depending on what equipment and materials they have handy, especially if nobody quite realizes yet how critical some of those steps might be.
The fusion of a deuterium and tritium nucleus requires that the 56 kev barrier be overcome. Imagine how good you'd have to be to cause these nuclei to bypass that barrier entirely at very low energy conditions. It's equivalent to claiming that you can ignite paper in cryogenic temperatures using a suitable catalyst. I just don't think it is very likely given what needs to be overcome.
You might want to look up "muon catalyzed fusion". Yeah, there's a 56kev barrier (for D-T, and whatever it is for D-D) to overcome for fast-moving tritons and deuterons. There are other ways to get those particles close enough that their probable locations overlap and they fuse, it's just a matter of reducing the local strength of their repulsive electric field by countering it with opposite charge (as with a muon). Problem with that is, muons don't last very long. There may, may, be other ways to do it, and matter in the solid state has rather different properties from plasmas.
And there's the rub... if cold fusion is "COLD", then how do we utilize the energy?
Poor choice of words. "Condensed matter fusion" might be more accurate (assuming there's any fusion at all, of course). It's only cold relative to plasma-state fusion, if it generates heat enough to boil water it can produce power, and yet still be called "cold".
On the other hand, if it generates cold, we could use it for refrigerators ;-)
Anonymous Bob - if you did vote libertarian all you did was help elect Obama
That's what the Republicans want you to believe. The fact is that the only thing that helped elect Obama was votes for Obama. There are plenty of issues (more social than economic) where voters might lean Democratic rather than Republican and might end up voting Libertarian because they can't stomach Democratic economic policy, just as they might favor Republicans on economic issues (or might have pre-Bush) but can't stomach their stand on some social issues.
Show me a libertarian who has a snowball's chance in hell of winning, and I'll vote for him.
Substitute any third party for 'libertarian' above and your statement makes just as little sense.
What's the point of voting for someone who is going to win anyway? Might as well just stay home. Of course, the two major parties would have you believe that if you don't vote for a major party candidate, you're just "wasting your vote" -- which is utter bullshit. You're only wasting your vote if you vote for someone who doesn't support the policies you believe in. Yeah, your guy may not get elected, but at least you did your bit -- and if enough other people feel the same way you do (including rejecting the nonense about "wasting votes"), then your guy might actually make it.
Or at least put a big enough dent in the major parties' vote numbers to make them reconsider their policies.
Cleaning fluid? $150?
My boy, you got taken.
The name doesn't make it any better, after all.
Well, beyond a certain point, no. But an $80 "Rolex" copy isn't anywhere near that point (especially since it's guts are probably those of a $10 watch). If you really need an accurate timepiece that can stand up to the rigors that Rolexes, Omegas, etc are designed for (eg you're a diver, or a pilot, or otherwise venture where wear-and-tear will destroy that $10 watch in no time), then you'll have to pay a bit more.
But not $8000 -- a $300 Seiko (for example) will probably do about as well.
Or get an electric shaver. A little bit more up-front cost, but it should last a decade or two. I mean, really, blades? How quaint.
Not so much any more, but in the early seasons of Smallville, Lionel Luthor kept reminding me of Larry Ellison, only with longer hair.
I can't wait to see the reconstructed skeletons of these things.
Oh, wait..
Yep, I posted below about DansGuardian. Wonderful tool.
It doesn't take much in the way of resources -- I have it (and Squid proxy) running on an old Pentium-166 with a mere 96MB RAM (and SuSE 9.3). Wouldn't surprise me if you could run it on a linux-based router.
Sure, the "best" (qualitatively) filter is to watch over your kid's shoulder -- but with three kids (each with their own computer) and other things that need doing around the house, that's not always possible.
One thing I might want (and I haven't even looked to see if it's possible) is a way to tailor the filtering to different IPs, so that for example my teenager gets a somewhat more relaxed set of rules than my two pre-teens. I suppose I could always run multiple instances on different ports, with the firewall redirecting as appropriate.
I use DansGuardian. Easy to configure and works fine (I use it conjunction with squidproxy, both running on the firewall between the DMZ and inside the house).
Occasionally I'll go in and configure it to block Flash (except for certain sites, like the kids' schools) to discourage playing flash games when they should be doing homework. If one really wanted, one could configure a cron script to modify the configs at different times of the day (I don't think dansguardian config files are smart enough to do that themselves), but I haven't bothered.
Since only the kids' computers go through DG, (that's in the firewall config) if I want to cut them off from the internet in a hurry I can just kill that, leaving the rest of the computers on the net.
I don't know about other filters -- I tried DG first and it was Good Enough -- but if they do try to hit a blocked site it will pop up a page (configurable) telling them to ask Daddy if it's something they really need access to.
OTOH, by the time you reach my age, there aren't that many totally new situations.
Or perhaps you've learned to anticipate and avoid them.
Still, there's something to be said for gaining a lot of different experiences early on, so that indeed totally new situations are rarer. That's something I did, although not necessarily with that end in mind.
So yea, youth and energy are nice, but they fade as experience comes to the fore
Yep, old age and treachery will beat youth and skill every time.
More seriously, it's faster and more efficient to retrieve a problem solution from memory than to solve it from first principles -- heck, with sufficient experience you recognize incipient problems before they start -- so as long as the RAM holds out it doesn't matter if the CPU speed starts to slip.
Of course that doesn't apply to adapting to totally new situations, something that youth has long known to be better at on average.
It was an FBI sniper at Ruby Ridge.
It was also the FBI Hostage Roasting, er, Rescue Team that was responsible for the fire at the Branch-Davidian compound in Waco.
The BATF hardly has a monopoly on screwing up big time, whether through malice or incompetence.
CO2 isn't toxic,
Oh? Put a plastic bag over your head, let me know how long you last. You can even have an oxygen feed in there, you just have to let the CO2 build up.
Converting coal to a "cleaner form of energy" just means you're taking the "dirty" parts out before it gets to the end user -- you still need to dispose of the crud, like mercury, arsenic, thorium, radon, sulfur, complex carbon compounds that don't easily convert to your fuel du jour, etc. And burning that fuel du jour still produces CO2.
Coal waste is far more toxic per watt produced than any other means of energy production, including nuclear.
"Clean coal" is an oxymoron, like "jumbo shrimp" or "reality TV".
Never mind the CO2 that coal plants produce.
Indeed, never mind the things like arsenic (that remain toxic forever) that are in coal ash.
The fact is, if coal plants had to meet the same standards for radioactive release that nuclear plants do, they'd all have to be shut down. There's all kinds of radioactive stuff in coal (radon, thorium, etc) -- not very much per ton, but coal plants burn millions of tons of the stuff. Indeed, if you could extract the thorium from coal you'd get more energy burning it in a reactor than you would from burning the carbon in a furnace. (Don't take my word, look it up.)
"Clean coal" is an oxymoron.
The Microsoft v Tom-Tom suit covers a half-dozen or so patents, only two of them FAT-related. (Besides which, the FAT patent has been thrown out in Germany.) Most if not all of them are obvious or have prior art, like the FAT patents, and may well not hold up under Bilski. What does it gain Tom-Tom to license a (potential invalidatable) patent like FAT if they're still being sued over half a dozen others? If they have to go to court anyway, might as well try to get them all overturned - they can always offer to settle later.
And as final tongue-in-cheek example, have you used the Internet lately? Invented at CERN.
I'm guessing by "tongue-in-cheek" you mean "totally wrong".
The Internet was not invented at CERN -- it was invented by DARPA back in 1969 -- the World Wide Web (more specifically, HTTP) was invented at CERN.
What is this preemption you speak of?
I haven't watched broadcast TV in years (well, maybe a couple of times). I'll happily wait a year for episodes of the few shows worth watching to come out on DVD, then I can watch what I want to watch when I want to -- no commercials, no preemptions, and if I want to watch four episodes of, say, Lost or a double episode of Dr. Who back-to-back, I can.
(And yeah, I know I could probably find the stuff online before it comes out on DVD, but that has its own set of headaches.)