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Table Top Fusion Courtesy of Tiny Bubbles
Erik Baard writes: "The peer-reviewed journal Science is carrying a cover story about the possibility of table top fusion. Not cold fusion, mind you, but the apparatus might look that way to some. Oak Ridge and other labs say they have gotten the fingerprints of fusion (neutron production) from collapsing bubbles in liquid, a process that heats a local area to temperatures as hot as the surface of the sun, and releases photons.
The disputes are already here -- notably from Dr. Robert Park of the American Physical Society and from critical reviewers who say they haven't repeated the neutron production. But the authors say the critics didn't calibrate their equipment correctly. Articles regarding the discovery can be found on
Eureka Alert " CD: Looks legit, but Pons and Fleishman (and the University of Utah for that matter) talked a good game. I suppose I'll belive in tabletop fusion when a generator comes atached to my next laptop. The author of this post also has a longer article up at the Village Voice
...gives us a perverted version of this, complete with futuristic pseudo-prophetic babble that is characteristic of this journal.
./'ers frown upon the sometimes-Enquirer-like nature of this magazine's reporting...
This isn't a troll, I am just curious to hear how many other
-JT
Dr. Park is a professional naysayer, and he's got a safe gamble. Most weird new ideas are just that, weird. But he blasted the paper before they could even publish it, breaking the journal's embargo -- that's unfair at the very least.
More here: http://villagevoice.com/issues/0210/baard.php
I'm concerned that it hasn't been duplicated yet, but hopeful.
Jherico
What can the average user can do to ensure his security? "Nothing, you're screwed"
I built a single flask apparatus as a senior year thesis as an undergrad...we actually got it to work too. Is it fusion? Now that I'm actually in a plasma physics graduate program I find it very doubtful that what is going on inside those very very small bubbles is actually fusion. I'd love to be able to get back to sono and make a better study of it using some of the plasma knowledge. If it is fusion it has to work along the same lines as ICF..but instead of lasers you have acoustic energy. My feeling when I was working to build the eperiment was that the effect was extremely dependant of the spacial symmetry of the system and the gas content of the liquid...in my case simply water and air. Maybe nanotube technology might provide a way to accurately probe the region near the bubble without perturbing it.
.
The big pain of it is the bubbles are so small its extremely hard to make measurenents. Back in 98 when I did my experiment it wasnt even clear in the literature if the light was black body nor what temperature the radiation source was. The water surrounding the bubble has a cut off in the ultra violet and the peak frequency in the emitted light was not observable. I think we found some rather crude theories of shock wave development to would explain some ionization..but i dont think the theories made any estimates of temperatures rivaling that needed for a useful fusion cross section...but of course I didn't know much plasma physics then...it would be interesting to model this in the way ICF target implosion is modeled
If its fusion...I can't imagine this be an extremely useful power source...the bubbles are so small and short lived...if extractable power were produceable I'd imagine the power would heat the sorrounding liquid to the point that the gas dynamics driving the bubble formation would break down well before you could extract any useful heat load from the bulk volume.
Even it its not fusion temperatures in the bubble...its still a very interesting effect....pico sized oven for chemical reactions. Nanotube technology is big now...a pico sized high temp reaction chamber might be very useful for nanotech. My parter and I had a whole shopping list of crude measurements we wanted to try making . Looking for some assymetries in the radiation pattern was the one we really wanted to do.
-jef
Okay, if you had read the article, you would know that this is barely the first step. They haven't even ascertained if the reaction produces more energy than what it requires to sustain. If it doesn't (with this method), then it's just an interesting way to produce neutrons and tritium, period.
Second, IF it is determined that more energy is coming out than goes in, a way has to be devised for the neutrons of one set of reactions to seed the next set (preferably the next hundred set).
Third, just because something is potentially dangerous doesn't mean we should restrict it. AN OBJECT IS DEAD WITHOUT AN ACT OF WILL TO USE IT! If you've got problems with the way people use technology, then you need to go after the causes, the reasons WHY people decide to do nasty things, not try to restrict the technology itself.
You know, if flight technology had been restricted, the events of 9/11 would never have occured..
"Avast! Prepare for the rodgering!" THWACK! "Arrr.. me nards.."
See for example this, or this.
"I'm not hot doggin ya!"
-dB
"It if was easy to do, we'd find someone cheaper than you to do it."
What really gets my goat is that the editors of Slashdot are apparently unaware of the position of the U.S. Navy's Naval Ocean Systems Center in favor of cold fusion, and their long-suffering and pioneering work on the particular kind known as codeposition fusion:
http://www.spawar.navy.mil/sti/publications/pubs/t r/1696/tr1696.pdf
I have copied that tech report, along with a diagram you can use to do cold fusion on your desktop for less than US$500, in this directory:
http://www.bovik.org/codeposition
Please mod me up; I am posting as AC due to time pressures and a different browser in use at the moment. Thanks in advance.
Sincerely,
James Salsman
james at bovik dot org
Since most of the web pages I have seen are either basic (it is a bubble, it makes light, try it) or has information that seems to be full of errors and typos. I have found a quite a few papers on environment modifications resulting changes in output but am at a loss for hard data. the best site that I have found is one by Sci. Am. and I think most people here already that half there stuff is crap (they cant tell the diffrence between F and K SciAm:Ask the experts:Phy
And since I am still in HS I dont have a chance in hell of getting access to a decent library (or online access to nature/science/ojps/etc...). Oh well its only another month or two.
Information wants to be free like speech wants to be free, not like we want beer to be free.
Also, in balance, remember Clarke's Law on this matter:
"When a distinguished elder scientist states something is impossible, he is almost always wrong."
-Arthur C. Clarke
Since you asked ... inside a flourescent light tube is argon at a pressure of 3 Torr and mercury at a pressure of 1 Torr (for reference, atmospheric pressure is at about 760 Torr).
... I'll leave it to you to think of household devices which have high energy density.
A electric discharge creates a plasma such that a fraction of the argon and mercury become ionized (it is a very small fraction). As a result, lots of free electrons are running around. Some of these electrons cause excitation of mercury (either directly or indirectly) which after some radiation transport magic is converted to visible light. Some of the electrons cause further ionization which keeps the discharge around.
For ionization and excitation to occur, the electrons have to be at a high temperature. Argon ionizes at 15eV and to have enough electrons that hot you need electron temperatures over 10,000K (typically 40,000K+). The conversion is roughly 1eV to 11,600K.
The catch is that the electron mass is about 70,000 times less than that of argon. To picture what is going on, electrons are ping-pong balls and argon / mercury are bowling balls. Even if you throw a ping-pong ball really really hard, a bowling ball won't notice it.
As a result, the electrons are able to heat up to very high temperatures. Meanwhile, the glass tube at room temperature keeps the Ar/Hg mix cool. Thus, even though the electron temperatures are high, the heat conduction is incredibly low and the tube feels cold to the touch.
Since this site is interested in computers, these types of plasmas are used in almost every step of semiconductor processing. Because the electron energies are so high, exotic high temperature chemisty can be performed without melting your wafer. And because there are charged species, etchant flux can be electrically manipulated (which is why you have microchips which small features nowadays; look up plasma enhanced anisotropic etching).
As for dangerous experiments, I can think of a few but rather than get sued
Kevin
Here's the problem: Copyright violations. Believe me, I'd love to. But we can't because of that. People have asked how Google caches - frankly, I don't know how they legally do that. But because we're a content site, versus a search engine, we would be more liable for reprinting without permission which is a big No No in all print/editorial media.
Yeah, I'm that guy.
Here's a suggested course of action, it might suck, but its just a suggestion:
/. reports breaking news; cool stuff yes, breaking and time sensitive, no. If there is no reply, just link the original site. If the webmaster gives permission, link both the mirror and the original, and encourage the original unless the webmaster says otherwise (give this choice in your sp^H^H form letter)
1) Mirror the site privately, no public links. This should fall under fair use as long as nobody is able to access it from the slashdot main page.
2) Send an email to the webmaster stating that you are about to link to his site, thus throwing an ungodly amount of hits his way, and that you can toss up a mirror to reduce the strain on his poor, poor webservers.
3) Wait a hour or two for a reply. Its not like
Tim
I just finished reading Park's book "Voodoo Science - The Road From Foolishness to Fraud" (ISBN 0-19-514710-3) - and a central theme throughout the book is his "annoyance" (ok, that is putting it kindly) with scientists and inventors who either get caught up in their experiments and go down a self-deception path (Pons/Fleishmann, Joseph Newmann) or those who outright deceive others for monetary gain.
The way this is sounding - it is sounding like so much "voodoo science", simply because of the irreproducibility of it (but, who knows? Maybe others will have success - may be too early to tell)...
Reason is the Path to God - Anon
It also explains why 2.45 Mev neutrons, which Teleyarkhan claims are the byproduct of the fusion of Hydrogen-2 into Helium-3, are seen coming out of the flask. They are simply 14 Mev neutrons which have slowed down by bouncing off various nuclei.
The article that is linked to does NOT claim that this is a viable source of energy.
It does claim that fusion is a possible explanation for sonoluminescence and that the results are still under review.
I would like to say this at this juncture. The discipline of science requires the vigorous investigation of phenomena, explanation of phenomena, and the vigorous critical review of explanations of phenomena.
All of this requires public review as often as possible. Vast misinterpretation of reports and massive derision do not help the cause of science.
The researchers claim simply that sonoluminescence may be explained by fusion achieved when a)the proper isotopes are present and b)small bubbles collapse to generate high energy for a moment. This ocurs after seeding with neutrons.
Sounds plausible to me. They do explain how this is happening, and performed a control test. Next comes replication of results. And please folks, dont rely on the first two attempts. Do you think the first replications of experiments by the Wright Brothers, Fermi, Marconi, or Tesla worked? Science is rife with failure to the extent that after something graduates to technology it is still not reproducible. Anyone ever buy a solid state laser that did not work? Does that mean that laser theory is wrong?
Besides, one reason we all measure gravity in high school physics is because we are rigorosly testing Newton. Every time. Every calculation. To make sure.
This is not religion, it does not happen overnight. The Science Pope cannot decree "fusion in a bottle". It might just mean that here there be fusion at an overall loss.
I for one hope it is true, it could be a way to regain energy as pressure increases outside an airframe during reentry, utilizing the increasing air pressure to drive the fusion process.
Dont be so quick to deride this, dont be too quick to embrace it. Remain skeptical as to it's possibility and it's uses. Just cause it seems so, dont mean it is. And just cause it's not know dont mean it wont.
Only up to a point - a 31 year old researcher may be in a better position to question the orthodox theory than a 21 year old one, but he's also far more likely to do so than the average 61 year old professor. New and radical theories tend to finally win out when the younger researchers become the senior lecturers and the supporters of the old one retire.
I mostly agree to you, but I just have to be a little pedantic...:)
Regarding the number of neutrons produced by fusion and fission reactions, yes a D-T fusion reaction produces only one neutron while a U or Pu fission produces between about 3, depending on energy. But take into account that a single fusion reaction produces only 17.6 MeV while a single fission produces about 200 MeV. Add to that the fact that a large fraction of the neutrons in a fission reaction are used for inducing further fissions in the material. Remember neutron bombs? Tactical nukes meant to kill the crews of sovient tank hordes, while hopefully leaving the rest of West Germany relatively intact. They had very minimal amount of fission material in them, about 95% of the energy produced was by fusion. The reason was to have a as high as possible neutron flux, and also to minimize fallout. Most strategic warheads deployed today have only about 50% fusion output. The reason is that the casings are made of enriched uranium, the reason being that the Ulam-Teller staged radiation implosion type bomb needs a casing made of high-Z material for refllecting x-rays produced by the primary. So by additionally making the casing of fissionable material (it wont fission by itself, only fission induced by the fusion neutrons) you get better bang-for-weight.
And regarding detonating a fusion bomb without a fission primary, I read some rumors a while ago that the russians reportedly had some chemical explosive called "red mercury" capable of detonating a fusion bomb directly. As it IMHO sounds quite improbable, I'd guess it's just some rumor.