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More Evidence for Tabletop Fusion
Posted by
Zonk
on Sat Jul 16, 2005 11:27 PM
from the my-favorite-atomic-reaction dept.
from the my-favorite-atomic-reaction dept.
heptapod writes "Researchers at Purdue University have statistically significant evidence that their tabletop fusion experiments were successful. Yiban Xu's experiment different from an earlier Oak Ridge experiment using a different and cheaper source of neutrons than Oak Ridge's pulse neutron generator. Surpassing break-even point still eludes the grasp of science."
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Bubble Fusion Researcher Faces Fraud Trial 154 comments
An anonymous reader writes "In 2001, Rusi P. Taleyarkhan shocked the world by claiming he had successfully produced a positive net energy bubble fusion reaction; cold fusion. The New York Times reports that a congressional hearing is now under way against Taleyarkhan, even though Purdue University has already cleared the scientist of any wrongdoing. Dr. Taleyarkhan said last night in an e-mail message that the subcommittee's report represents 'a gross travesty of justice.' He asked, 'Where are the Jesse Jacksons and Al Sharptons of the Asian community during this episode that has caused this biased and openly one-sided smear campaign?' You can view the full (colorful) e-mail at Dailytech."
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Science: "Tabletop" Fusion Researcher Committed Scientific Misconduct 161 comments
Geoffrey.landis writes "A Purdue University panel investigated allegations against nuclear engineering professor Rusi Taleyarkhan, finding that he had in fact committed scientific misconduct in his work.
Taleyarkhan had published papers in which he reported seeing evidence of nuclear fusion in the collapse of tiny bubbles in a liquid subjected to ultrasonic excitation — a finding that would be groundbreaking, if true, but one that apparently could not be replicated by other researchers. The allegations against Taleyarkhan were made in March of 2006. A local Indiana paper gives the full list of allegations against Taleyarkhan, and the resolution of each by the panel. The full report (PDF) is also available. Of the nine specific allegations, only two were found to comprise scientific misconduct. The committee 'could not find any other instances of scientists being able to replicate Taleyarkhan's results without Taleyarkhan having direct involvement with the experiments,' but notes that this comes 'just short of questioning whether Taleyarkhan's results were fraudulent.'"
We've discussed this gentleman's work and the scrutiny it has received several times, and members of the scientific community seem to have given him the benefit of the doubt in many cases.
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Break Even is Easy... (Score:2, Informative)
Someone say breakeven? (Score:3, Interesting)
hmmm does it [atominfo.org]?
Re:Someone say breakeven? (Score:5, Insightful)
If you are referring to the energy required to produce the plutonium and to separate the deuterium from water then they still VASTLY exceed in energy output the energy required to produce these things, as a typical fusion bomb is capable of releasing energies in the PETAjoule range (>10^15J).
Parent
Re:Someone say breakeven? (Score:3, Interesting)
Re:Someone say breakeven? (Score:4, Informative)
It's possible to build boosted fission primaries with fission efficiency up to about 50%. Such have been built and weaponized. Modern US devices have less efficiency (around 15%, in rough terms) because they are designed to use as little fissile material as possible and to be one-point safe, and also to have limited overall fission yield. Those requirements lead to less efficient weapons than are possible and were used in the past.
Second, fusion, stages can be both highly efficient (50% or more of the possible fusion energy content) and have very high multiplication ratios of input to output energy (factor of 25 is possible, with factors of 8-15 in deployed US weapons), even before you double it again with a fissionable tamper third stage.
Look at references like the Nuclear Weapons FAQ at http://nuclearweaponarchive.org/ [nuclearweaponarchive.org]
Parent
Re:Someone say breakeven? (Score:3, Insightful)
In which case your figures are way high. Fission bombs only convert about 0.001% of their mass to energy, early fusion bombs about 0.007%. The latter figure may be higher for modern weapons, but no where near 20%, or even 2%. I might believe 0.02%.
ARTICLE MIRROR FOLLOWS (Score:5, Funny)
Fusion (Score:4, Funny)
Re:Fusion (Score:2)
Re:Fusion (Score:3, Funny)
Re: More Evidence for Tabletop Fusion (Score:5, Informative)
Re: More Evidence for Tabletop Fusion (Score:3, Insightful)
I agree that mainstream fusion work will be important and is probably the right track toward a practical fusion powerplant.
However, remember that Cathode Ray tubes were also once little more than a labtable source of tightly controlled electrons. New sources of materials often lead into practical applications not originally envisioned.
Re: More Evidence for Tabletop Fusion (Score:3, Insightful)
This is so true. No-one making velcro thought it would be good for strippers. It took their wives to figure that one out.
Re: More Evidence for Tabletop Fusion (Score:3, Interesting)
Re: More Evidence for Tabletop Fusion (Score:3, Informative)
I may not be the GP, but I'll throw in my $.02 as a fusion science researcher. (I work on a magnetic confinement device myself.)
1) The running joke of fusion is that it's always 30-50 years away. This is more due to meager funding levels than anything else. At a talk by a PPPL scientist a few years back, it was mentioned that if one plots the price of oil and the amount allocated for fusion research versus year, they track rather nicely. (The 70's were a great time to be in the field!)
Why the meager fu
Re: More Evidence for Tabletop Fusion (Score:3, Interesting)
I hear it's ~10 $G for iter. That's not exactly chump-change. Especially since we're not actually sure that even after ITER we'll have a working plant or a path to one. In addition, your scaling arguments (I've heard elsewhere t
break-even (Score:5, Insightful)
It reminds me of when people say hydrogen burning cars will solve all emition problems because they produce water. They don't count the emissions that may be needed to produce, compress and ship the hydrogen to the nearest gas station.
break-even isn't always the only concern... (Score:5, Insightful)
The trick with this one is in the may.
Maybe someday we'll find a technology that's clean-burning and energy-efficient to the point where oil is no longer the most cost-effective way to make energy. Say, maybe nuclear fusion. Or maybe oil will eventually get so expensive that other energy technologies start to look not so bad by comparison. But if we ever reach this point, because of the massive installed base and economies of scale of oil systems, especially the ones in cars, we and our economies will still be dependent on oil. So it won't matter that the newer technology is better, we'll keep using oil anyway. That's bad.
Hydrogen may at first be ultimately dependent on "dirty" oil and coal to make the hydrogen in the first place, but because it decouples energy production from energy use, in the long run it gives us the capacity to move on to better energy sources. It's like a nicotine patch, okay, it technically doesn't address the addiction but the thing is eventually you get to take the nicotine patch off.
On top of this, there are situations where if you can't eliminate emissions, moving the emissions is a desirable second best thing. Like, of course we're not making advances in our contribution to global CO2 levels if all these cars in the city burning oil are replaced with a bunch of cars burning hydrogen [PLUS] one huge smoke-belching oil-burning hydrogen plant. But, well, if the city is Los Angeles, and the city is basically one huge smog-trapping bowl surrounded by mountains, and the smoke-belching hydrogen plant is on the other side of the mountains, then never mind the global CO2 levels, you've still made Los Angeles a significantly more pleasant place to live.
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Re:break-even isn't always the only concern... (Score:3, Insightful)
Don't forget that a million tiny engines that often burn fuel wastefully or ineffeciently pollute a heck of a lot more than one plant burning the same fuel but operating all the time at peak effeciency.
To say nothing of the more environmentally friendly scurbbers that can be applied to a smokestack.
Re:break-even isn't always the only concern... (Score:3, Insightful)
True, but IMO putting the focus on the hydrogen-aspect is wrong. The
Re:break-even isn't always the only concern... (Score:5, Insightful)
There is no doubt about that. Noble goals of reducing emissions and all that are great, but the sad fact is that companies are basically controlled by very greedy individuals. If they can be convinced that the company can "break into a new market segment" and have "tremendous growth potential" then they will throw money at whatever it is without much hesitation.
Actually, the oil industry is writing its own epitaph by failing to keep prices down. At the current price levels, oil is only just slightly cheaper than some alternate fuels. I've heard an estimate that if gasoline were $4 per gallon then hydrogen becomes competitive. If oil prices go up much more then suddenly some other fuel will become more attractive and the fuel wars will begin in earnest.
The thing is, oil is a finite resource and its price can ultimately only increase. Alternative fuels are typically synthesized and their price will eventually drop as better technology improves their production process. Because the alternatives are created from raw materials which are essentially unlimited, their price is primarily dependant on the process used to synthesize them.
The question is: when will the two lines on the graph intersect. They are already drawing near enough that we are seeing things like biodiesel companies emerge. There will always be a niche market for fossil fuels, but decoupling cars and trucks from it would tremendously reduce consumption.
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Difficulty (Score:4, Funny)
Back to the Future (Score:4, Funny)
One more evidence.. (Score:3, Informative)
Re:One more evidence.. (Score:3, Informative)
More anything, it's the academic community generally, the NSF, etc that ridicules this work, not the government per se.
This is *NOT* cold fusion (Score:3, Informative)
Researchers have estimated that temperatures inside the imploding bubbles reach 10 million degrees Celsius and pressures comparable to 1,000 million earth atmospheres at sea level.
This is NOT cold fusion, this is sonofusion.
Quick DIY Guide to Fusion in your basement (Score:4, Funny)
Seems pretty easy to me:
Step One: Build a sonoluminescence apperatus using an ocilloscope, a sine generator, audio amplifier, piezo transducers and spherical flask. Details here: http://www.physik3.gwdg.de/~rgeisle/nld/sbsl-howto .html [physik3.gwdg.de]
Step Two: Build a neutron supply source, problalby most easily constructed is a farnsworth-type fusor: http://en.wikipedia.org/wiki/Fusor [wikipedia.org] (makes a great science project too)
Step Three: Get some deuterium and dissolve it in acetone, place in your sonoluminescence apperatus and start tuning it to produce bubbles. Availible at your local scientific supply store.
Step Four: Build your own neutron detector and confirm the bubbles are producing fusion: http://home.earthlink.net/~jimlux/nuc/ncount.htm [earthlink.net]
Step Five: Become the envy of the neighbourhood as the only guy on your block with a nuclear fusion device in your garage! (to avoid police suspicion call it a magical glowing bubble maker)
Step 6: Profit!
Re:Quick DIY Guide to Fusion in your basement (Score:4, Informative)
Once you build a Farnsworth Fusor, you have a tabletop nuclear fusion device. Which part of "Fusor" was unclear?
If all you want is neutrons and to violate your local Nuclear-Free Zone, just stop at that point...
Parent
Source? (Score:3, Insightful)
I won't belive it until it's published on a peer reviewed journal.
Re:Source? (Score:5, Informative)
5+ standard deviations against the control is interesting. Should be easy to reproduce. (or not).
Parent
cheaper source of neutrons? (Score:3, Funny)
methods of fusion detection (Score:3, Interesting)
Now, these guys are using other methods of detecting fusion by neutron energy levels, and tritium. I just hope that the levels they detected were WAY above the statistical normal amount of 2.5MeV neutrons and tritium in deuterized-acetone controls.
tabletop fusion has been around for decades (Score:5, Informative)
Why don't we all have flying cars, then? Because you can't get a net energy gain with the Farnsworth Fusor--it seems to be impossible in general to do so, the numbers just don't work out.
Of course, even if you do make it efficient, it's not exactly "clean energy": even with so-called aneutronic fusion, a few percent of the fusion reactions will generate neutrons, which, for realistic power generation, results in a neutron flux that causes the power generation to be quite dirty. Not as dirty as fission--disposal should be easier--but don't expect something harmless you can just run in your basement.
So, tabletop fusion isn't really anything impressive: there are probably lots of ways of getting fusion on your tabletop. The question is how you make it efficient enough to useful amounts of energy out of it. And cavitation seems no more promising there than inertial confinement in the Farnsworth Fusor. But maybe if enough people keep playing around with this, someone will get lucky and find something that works.
Rusi Taleyarkhan's fusion debunked by BBC Horizon (Score:5, Interesting)
Re:Abuse (Score:5, Interesting)
This question is one I've been thinking about for a few years now due to an idea for an invention I've got (not cold fusion, though), plus some stories I know of. The most relevant one is an episode of Outer Limits (the series from the 90s, not the one from the 60s).
In the story, an expelled physics student detonates a small 'cold fusion bomb' in a campus clocktower as proof of the technology, then takes a physics class hostage with another device. He demands that the people who have tormented him in the past be brought to the courtyard and shot in front of him, or he'll detonate the more powerful device he's got with him.
While the military is trying to figure out what the hell it was that detonated (since they don't believe in a cold fusion bomb), the negotiator is trying to figure out what the deal is with the hostagetaker. It comes out that, among other things, he believes there's a reason we've not found any signals from other species. The cold fusion technology is so simple that anyone can make it. When a species gets advanced enough to realize how easy cold fusion is, he says it's inevitable that a species will destroy itself before it can get mature enough to handle its technology. The negotiator then says, well, tell us what led you to the idea, and we can try to steer science around that until we can mature enough to handle it. The guy thinks back to what started him on the path to cold fusion - a physics test with the question, "Demonstrate why cold fusion is impossible."
I'd say it's inevitable that we WILL have this technology. How simple it winds up being is unknown at this point, of course, but hopefully it'll be complex enough that not every nut in a garage can do it.
Parent
Re:Abuse (Score:5, Insightful)
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Re:Abuse (Score:5, Funny)
That's the very question currently being asked at the Pentagon. Just what will our government due when a drop on productivity is caused by millions listening to music with an ever-lasting battery in their iPods?
Parent
Re:Cars? (Score:5, Interesting)
Some genius figured out that providing every man, woman, and child with sufficient nuclear material to create an atomic pile wasn't such a good idea?
From a technology perspective, there were a few other problems as well. Off the top of my head:
- Radiation: You need a lot of shielding to stop the "hard" stuff like Gamma, Neutron, and X-Ray bursts from escaping a functioning pile.
- Weight: All that shielding results in a lot of extra weight.
- Inefficiency: A "simple" atomic pile may be relatively safe (from a runaway reaction perspective), but it's not particularly efficient, nor can it be actively controlled.
In any case, the Ford atom car was never seriously developed. It was just an "Atoms for Peace" idea that was kicked around as a promotional gig.
A far better use for nuclear tech is in Merchant ships. Today's merchies pay extraordinary amounts for diesel fuel, have limited range, and burn fuel at the rate of gallons per feet. Nuclear reactors could provide these ships with more cargo space (no fuel tanks!), greater speed, longer endurance, and better turn-around times.
Unfortunately, the case of the NS Savannah [wikipedia.org] turned off the private sector to the idea of a nuclear merchant ship. There was no real problem with the ship herself, but rather the fact that she was ahead of her time (crude was still VERY cheap back then) and one of a kind (no infrastructure to support her) meant that she couldn't compete in the market.
The equation today is a very different one from the equation back then, but concerns related to the control of reactors and nuclear fuels have placed road-blocks in the way of reviving the idea.
Parent
Re:Cars? (Score:5, Interesting)
That heavy diesel fuel is nasty stuff. Basically, its what's left over after they boil off all of the gasses, gasoline, kerosene, road use diesel fuel and the lower grade heating oils. They have to pre-heat it quite a bit to get it to burn in an engine, otherwise it's about as good as filtered crude oil--slightly less viscous.
Nuclear power would be a huge step forward in this area... I can't agree more. Throw in some modern reactor and propulsion designs and you'd have a terribly efficient and manuverable ship. Might even make fuel a bit cheaper for the rest of us if it caught on... Bonus.
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Re:Cars? (Score:4, Interesting)
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Re:Cars? (Score:3, Informative)
SPOILER WARNING! (Score:3, Informative)
Re:Cars? (Score:5, Informative)
http://geology.cr.usgs.gov/energy/factshts/163-97
http://www.ornl.gov/info/ornlreview/rev26-34/text
http://yarchive.net/nuke/coal_radiation.html [yarchive.net]
Parent
Re:But then again... (Score:4, Informative)
The industrial revolution started because of forest depletion in England which meant that they had to switch to coal. In order to get to the coal they invented the steam engine to pump water out of mines and lift people into and out of them. The invention of the steam engine had the wonderful side effect of bringing forth the industrial revolution from which we all benefited.
If you want to read about the reasons for societal development and collapse by a academic whose works on civilization have stood the test of time and explain the Roman, Mayan, Mezoamerican and Egyptian collapses all with the same theory I suggest you read Tainter's collapse of complex societies. The west has saved itself from collapse for longer than any other civilization out there because we have had the wonderful luck to constantly innovate ourselves out of the corners we get into. There were many times throughout the Renaissance and the industrial revolution that European society could have collapsed but we always managed to pull ourselves out of it via technolgy.
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Truly an expert opinion. (Score:5, Funny)
However, as a pastry chef, I know that the Krebs cycle causes metal fatigue in steel structural support beams.
However, as a ballerina, I know that the Pythagorean theorem causes the release of neutrons from radioactive material.
However, as a professor of French literature, I know that penicillin causes cost overruns in long-haul LTL shipping.
Parent
Re:But then again... (Score:4, Insightful)
I would love to see some hard documentary evidence on this point. From my knowledge of history, it was precisely the use of coal as a fuel source that triggered the Industrial Revolution. Almost immediately prior to the widespread use of coal in England, the primary fuel source was wood or hydro power (for running mills and stuff). There was a huge debate in England at the time because the forests were visibly disappearing from all over the British Isles, and doom and gloom were predicted (as supposedly did happen at Easter Island). After coal was used in large quantities, England went from a largly agrarian lifestyle and small villages (London had only about 30,000 people in the year 1400) to a major industrial power. The use of coal had a major impact on that occuring.
When coal was finally excavated in large quantities, there was a need for bulk shipments of the stuff overland to larger concentrations of people who needed it. From this came railroads, steel production, mechanical and civil engineering, and a modern industrial economy.
As far as the Great Depression being caused by a shift from coal to oil, that is incredibly simplistic, and there were many causes for what happened, including a lack of securities oversight (triggering the Wall Street Stock Market Crash of 1929), overproduction of food stocks, preditory pricing companies, and reconstruction issues from WWI where the bill to pay for that awful war finally came due and had to be paid. Conversion from coal to oil may be there as a slight cause, but nearly as significant with those fuel sources was the conversion from passenger rail travel to personal automobiles... which really didn't happen until the 1950's in the USA anyway.
What a fusion energy economy would actually provide is a cheap energy source that would cause a huge expansion of economic resources for just about everybody, even in the most poor parts of the world.
It could be argued that the wealth a person has is determined by the amount of raw power that they have available to do what they want to accomplish. This is actual power, as measured in kilowatt-hours, joules, or whatever. If you want to increase the wealth of a region, you need to provide energy resources that will allow the people in that area to be able to accomplish whatever task they set their mind to accomplish. In this regard control of power is also control of political power, as utility companies are quite aware of.
What project like this tabletop device, a Fusor, or even Cold Fusion offer to provide is the potential that you don't need utility companies to provide this energy for you. If you need the power to run an air-conditioner, you just prime your fusion reactor with a little hydrogen gas and some water (to extract some more hydrogen gas). And not much water at that either. And no need for rolling blackouts or even power surges on the power grid.
Geeks successfully decentralized computing power, so why not power generation itself? I for one look strong with anticipation and excitement for the future this may bring.
BTW, I think it will be 1st world nations that will be able to take advantage of a hydrogen economy first before most 3rd world nations. If you look at China, they are incredibly heavy users of coal right now, with manufacturing plants that are actually producing steam-powered locomotives as new products (and hudreds to thousands of deaths every year in the coal mines from accidents). If anything the Chinese experience is that they have had to go through the entire industrial revolution, but at a greatly accelerated pace compared to most western European countries and North America. Africa is in political turmoil that almost seems to resemble what Europe was like in the early part of the 2nd millenium, and simply won't get much of anywhere (except for a few minor countries who get it) until they resolve their political issues and stop the nearly constant state of warfare in Africa.
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Re:But then again... (Score:3, Informative)
Or in other words, "as a geek, my knowledge of history is really skewed".
The Dark Ages were hundreds of years before the switch to coal. Coal mining started around the time the dark ages were ending (circa the 11th century), and the fuel economy didn't switch wholesale until hundreds of years after that.
Re:But then again... (Score:3, Funny)
Sure, you'd win, but what about Spock and T'Pol? What about Tuvok?
You're a Romulan in disguise! Admit it!
Re:neutrons are a major pollution:radioactive wast (Score:3, Informative)
An exaggeration. Hydrogen atoms, for example, merely become deuterium atoms, which are not radioactive.
Which is why neutron shielding tends to be made of things like lightweight polymers that contain lots of hydrogen atoms. (In the early days before modern plastics, they used paraffin wax.)
There are other materials that can happily absorb a neutron and go from one stable isotope to another.
Re:fuel sources. (Score:3, Informative)
In this case, the important ingredient is deuterium, which can be extracted from sea water. If there is anything that Earth has a lot of, it's sea water. So with any luck you are wrong.