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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
In this house we obey the laws of thermodynamics!
THE CRACKPOT INDEX by John Baez
A simple method for rating potentially revolutionary contributions to physics.
-5 point starting credit.
1 point for every statement that is widely agreed on to be false.
2 points for every statement that is clearly vacuous.
3 points for every statement that is logically inconsistent.
5 points for each such statement that is adhered to despite careful correction.
5 points for using a thought experiment that contradicts the results of a widely accepted real experiment.
5 points for each word in all capital letters (except for those with defective keyboards).
5 points for each mention of "Einstien", "Hawkins" or "Feynmann".
10 points for each claim that quantum mechanics is fundamentally misguided (without good evidence).
10 points for pointing out that you have gone to school, as if this were evidence of sanity.
10 points for beginning the description of your theory by saying how long you have been working on it.
10 points for mailing your theory to someone you don't know personally and asking them not to tell anyone else about it, for fear that your ideas will be stolen.
10 points for offering prize money to anyone who proves and/or finds any flaws in your theory.
10 points for each statement along the lines of "I'm not good at math, but my theory is conceptually right, so all I need is for someone to express it in terms of equations".
10 points for arguing that a current well-established theory is "only a theory", as if this were somehow a point against it.
10 points for arguing that while a current well-established theory predicts phenomena correctly, it doesn't explain "why" they occur, or fails to provide a "mechanism".
10 points for each favorable comparison of yourself to Einstein, or claim that special or general relativity are fundamentally misguided (without good evidence).
10 points for claiming that your work is on the cutting edge of a "paradigm shift".
20 points for suggesting that you deserve a Nobel prize.
20 points for each favorable comparison of yourself to Newton or claim that classical mechanics is fundamentally misguided (without good evidence).
20 points for every use of science fiction works or myths as if they were fact.
20 points for defending yourself by bringing up (real or imagined) ridicule accorded to your past theories.
20 points for each use of the phrase "hidebound reactionary".
20 points for each use of the phrase "self-appointed defender of the orthodoxy".
30 points for suggesting that a famous figure secretly disbelieved in a theory which he or she publicly supported. (E.g., that Feynman was a closet opponent of special relativity, as deduced by reading between the lines in his freshman physics textbooks.)
30 points for suggesting that Einstein, in his later years, was groping his way towards the ideas you now advocate.
30 points for claiming that your theories were developed by an extraterrestrial civilization (without good evidence).
40 points for comparing those who argue against your ideas to Nazis, stormtroopers, or brownshirts.
40 points for claiming that the "scientific establishment" is engaged in a "conspiracy" to prevent your work from gaining its well-deserved fame, or suchlike.
40 points for comparing yourself to Galileo, suggesting that a modern-day Inquisition is hard at work on your case, and so on.
40 points for claiming that when your theory is finally appreciated, present-day science will be seen for the sham it truly is. (30 more points for fantasizing about show trials in which scientists who mocked your theories will be forced to recant.)
50 points for claiming you have a revolutionary theory but giving no concrete testable predictions.
Sonoluminescence: an Introduction
Single Bubble Sonoluminescence HOWTO
Since sonoluminescence dosent seem to scale up (to my knowledge) this seems like a moot point. It is sort of cool to have a cheap way to study micro-fusion though.
Information wants to be free like speech wants to be free, not like we want beer to be free.
PDF copies can be downloaded from here.
Not really. Advance copies are usually provided before publication. These are usually available well before the article appears in print. It's certainly not considered unfair to comment on a scientific article in this manner and it happens all the time.
You'll notice the journal and/or the authors have announced the results to the media ahead of the print version being available too.
It's not like a TV station scooping a daily paper out of a story they researched or something like that.
BTW, I wouldn't consider him a professional nay-sayer, but rather skeptical, analytical (both good qualities in a scientist) and out spoken (which can be good or bad).
- a peer-reviewed article appearing in a major (if not the major) scientific journal,
- reporting an experimental result (not a business plan),
- that we're hearing about because the article is going to press (not because it was planned or submitted; admittedly, we're hearing it a little early because of advance reports).
These are all good signs of good science. The better sign will be attempts to reproduce the experiment, with both successes and failures published in the same professional manner.It's an extraordinary claim, and will require extraordinary evidence. Yes, this is just a first step; but at least it's in the right direction.
Stupid job ads, weird spam, occasional insight at
You too can make sonoluminescence happen. Try it with some deuterium and see if you can get fusion. Sound complicated, just use this easy to follow guide. It will give you step by step instructions for reproducing that special kind of magic that is sonoluminescence. All you need is:
- sinus generator: (sounds a bit painful)any function generator working around 25kHz, adjustable to +/-1Hz
(+/-10Hz may work, too)
- amplifier: nearly any kind of audio amplifier will do. If you're not sure, measure
the saturation voltage: 40V peak-to-peak should be enough.
- 2-trace oscilloscope
- 2 piezoceramic Transducers (drivers):around d=16mm in diameter, h=8mm thick
- piezoceramic pill-transducer (microphone):around 3mm in diameter, 1mm thick
- three finger clamp
- laboratory stand
- flask:take a 100ml Pyrex/Duran spherical flask, diameter 65mm, with a small neck. An industrial one has poor optical quality, so better take a free blown one.
- coil(s): around 20mH, see text
- resistors: 1M, 10k, 1R
- coaxial cable
- quick-drying epoxy glue
- an eyedropper or a syringe (one of those little do-it-yourself subcutaneous is very good)
- degassed distilled water:
- Pyrex/Duran Erlenmeyer flask (0.5 or 1l) and airtight stopper with pipe, rubber hose and clamp to close it
- aluminium/highgrade steel drinking bottle (0.5 or 1l) with screw cap; one of those found in camping stores, a bare one without varnish
- a bubble
;-)
oh, and it is nice to have:or
- second oscilloscope
- vacuum pump
- high-pass filter
- laser
Go for it kids. By the way, my favourite part is this quote: "Increase the driving voltage until you hear a horrible screeching noise, which sounds like your flask is going to crack. Don't be surprised if it does".I have to fill in some more text here, becasue slashdot sais I have too few characters per line. Well its just a bloody list of things. Of course there won't be much to each line, what do you expect?
"Me and my girl named bimbo . . . limbo . . . spam" - Captain Beefheart.
Here is a link Science Magazine is providing:
Science Magazine
It has a pdf version of the article in question. Here is the abstract.
The evidence for fusion-capable temperatures inside a sonoluminescing bubble lies in two main categories:
- You can examine the emission spectrum of the bubble. The spectrum is continuous, with a peak which depends on a variety of factors (noble gas content, temperature of the fluid, etc.), so you can try to figure out the temperature based on the emission expected from a blackbody of a similar temperature. The last I heard, the temperature was at least an order of magnitude less than what you would need.
- You can run simulations which make assumptions about the bubble collapse mechanism. If the bubble remains perfectly spherical during the collapse, then you may get the temperatures being quoted in the article. But there are other theories for the collapse, and requiring the bubble to remain perfectly spherical during a violent collapse doesn't seem intuitively obvious to me.
It's been a few years since I worked with this stuff, so take this with a grain of salt, but I'm not optimistic about this paper being validated."she says i'm lousy conversation. as if that's supposed to help."
In the "nice to have" section, it mentions a laser.
Well, der, I think this is obvious. Its always nice to have a laser. You could put this on basicaly any list of "nice to haves" for anything:
"Me and my girl named bimbo . . . limbo . . . spam" - Captain Beefheart.
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
I'm no scientist, and I've never researched the issues involved, so I'm certainly not proposing to pass judgement on whether this (extraordinary) claim has any likelihood of being justified, or whether Dr. Park's quoted reasoning is sound. But I will say that Dr. Park's eagerness not only to reject the possibility as quickly as possible but to quickly silence those who entertain the possibility through mockery as fast as possible cannot inspire confidence about his judgement.
Dr. Park and his ilk work to make a pariah of any scientist who gives any credence to an extraordinary claim which is subsequently proven false (or is considered to have been proven false, or in fact why bother waiting for proof at all?) The resulting social impulses to avoid exclusion and join in pelting the menacing sinner are what make this a powerful means of winning arguments. "Hark: A COLLECTIVE GROAN CAN BE HEARD . Better join in the groans fast before anyone starts looking your way!"
But for Heaven's sake, if we accept that the normal process of review will be able to effectively determine whether these results are sound or not, then the absolute worst that can happen is that some time and money will be spent in finding that the results are not sound, and that some people will thus be proven wrong. In science people are proven wrong, through the expenditure of some time and expense, all the damn time! Being willing to consider new ideas necessarily entails the risk that you will consider, or take seriously, ideas that turn out to be false. If you're terrified of ever believing something that turns out to be wrong, don't do scientific research. The exact same standard should hold for extraordinary claims as for more mundane ones: if they have some prima face credibility, let them join the rough-and-tumble of review. Extraordinary claims do merit searching, skeptical examination: those who make or consider them surely don't deserve any more or less odium than scientists who turn out to have been fraudulent, or foolish, or just mistaken in regard to more mundane ones.
Oh, and for all you freshly minted M.Sc.s and docs out there who are saddling up to join the posse and defend the faith in this forum: consider first that in all academic fields it tends to be the young postgrads who are loudest and most confident in defending the current thinking. Older academics are (on average, of course) a little less sure of themselves: could it possibly be that they have learned something?
"If the creation of nuclear technology became this simple, it not only gives terrorists an easier method to attain nuclear energy, but a way to actually create it themselves."
People like you are going to drive me prematurely bald...
Fusion reactors != fusion bombs
Fustion reactors are so damned far removed from fusion bombs that it's been about 50 years since we developed the second and we still haven't figured out the first. I'm willing to bet it will take at least another 50 years after the development of fusion reactors before we can make a fusion bomb that doesn't require a fission bomb to actually get the thing to go off.
"While it's true that a nuclear explosive based on this current method wouldn't spread as much harmful radiation as a uranium based explosive,"
You're right about that, but you have no idea how right you are.
First and foremost, the act of fission frees neutrons from their parent atoms. A lot of neutrons. Enough neutrons to set off the fission reaction. Fusion generates far fewer free neutrons (if at all, depending on your fuel) because it's busy trying to form atoms instead of breaking them apart.
Secondly, when people think of "radiation" from a bomb they think of the fallout (since the actual radiation from the explosion lasts as long as the actual explosion). Fusion in and of itself has no fallout. The fallout from modern hydrogen bombs is from the fission bomb that's used to set it off. No fission bomb, no fallout.
"it's potential damage far outweighs that of a dirty bomb."
Now here is where you need to lay off the crack pipe.
Getting a fission reaction to start is pretty easy: get a neutron-producer close to a clump of unstable atoms. Getting a fusion reaction to start, on the other hand, requires a LOT of input heat in the beginning in order to generate the plasma the reactions takes place in. So much heat that the pressure at the heart of Jupiter isn't enough to start a sustainable reaction. In the past 50 years the only way we've been able to pull it off is with a fission bomb.
But let's pretend that a pure fusion bomb is possible in the short term. Although it's possible to squeeze a fission bomb into something the size of a suitcase, your average 20 megaton device is more or less a cubic meter in size. But it's only that small because the heat generator is a tiny little suitcase-sized fission bomb. If we try to use a fusion reactor to generate the heat instead of a fission bomb, I don't see the device being small enough to fit into a cargo container (probably the largest possible size for a device to be useful to terrorists).
But what if they try to blow up a fusion power plant? Fission reactors are heavily shielded to keep the inside in. Probable fusion reactors would be heavily shielded to keep the outside out. If a tokomak loses magnetic containment, the plasma expands, cools, and reverts back to a gas. If it loses its physical containment, air gets in, conducts/convects away heat from the plasma, the plasma cools and reverts back to a gas. If you try to blow it up you just end up with a negligible amount of hot gas on top of the explosive.
Personally, I'd be a hell of a lot more frightened of an attack at a coal-fired plant. Have you ever seen what a spark can make coal dust do? Or what about popping off the fuel tanks at a natural gas power plant? And while I'm on the subject of boiling liquid-vapor explosions, oil refineries look awfully unprotected...