Cold Fusion Scientist Exonerated

Icarus1919 writes "New Scientist reports that the scientist who discovered a possible cold fusion reaction by bombarding a solvent with neutrons and sonic waves has recently been exonerated of accusations of scientific misconduct following the verification of his results by another scientist."

Comments

Odd.

[AKAImBatman]

Where's the cold fusion? The article sounds more like Sonofusion. Which, I can assure you, is a long ways from "cold".

Re:Odd.

[radtea]

Your definition of cold fusion is fusion happing at relatively low temperatures I take it?

Cold fusion is fusion that takes place when the fusing nuclei are at temperatures significantly below those required to overcome the Coulomb barrier. It has nothing to do with the temperature of the laboratory that the experiment takes place in, or the temperature of the majority of the mass of the apparatus. For example, we do not call tokomak's "cold fusion" because despite the fact that they sometimes use superconducting magnets and therefore are not just "cold" but positively cryogenic, the nuclei that do the fusing are HOT.

Any other use of the term "cold fusion" is terribly mis-leading for two reasons. One is that it invokes a completely arbitrary and unphysical division between various kinds of hot fusion, calling some kinds of hot fusion "cold" because someone happens to feel that it is important that some part of the apparatus that is not undergoing a fusion reaction is cold. The second reason is that it fails to distinguish between pressure-driven fusion of the kind claimed by Pons and Fleishman, and temperature-driven fusion which has actually been observed.

People who use "cold fusion" when they mean "sonofusion" are either honestly ignorant of the differences between hot fusion and cold fusion, or are being wilfully dishonest.

Despite the fact that neither Pons and Fleishman nor anyone else has ever been able to provide convincing evidence that pressure-driven fusion occurs between room-temperature nuclei, it is still the case that if anyone could figure out how to exert sufficient pressure, then the atoms would fuse, regardless of the amount of kinetic energy (that is, even at low temperatures.)

So there is a real distinction in the physics of "hot" and "cold" fusion, and in terms of that unambiguous and physically interesting distinction, sonofusion, if it happens at all, is almost certainly hot. Although if the centre of the bubbles really is as hot as they seem, it is a mystery as to why we don't see any neutron production in water, but only in more complex organic molecules--the phenomenon remains mysterious and there is still a lot of work to be done to reveal its secrets.

"accusser" was once on his staff

[andy314159pi]

The person accusing Taleyarkhan of misinterpreting data was one of his own post-docs. I wonder what that person has to say now? I think it's easy to make allegations and its difficult to shake the effects of false allegations.

What went on behind the closed doors?

[Ambitwistor]

Apparently, Purdue refused to state what the exact allegations investigated were, how many inquiries it conducted, or what its conclusions were based on. Hard to tell if the investigation's conclusions were arrived at fairly or were politically motivated. More details in this NYT article which I found from this blog entry.

Re:Doesn't mean he's *right*

[andy314159pi]

IAAPC and yeah I think the controversy was actually about whether the associated gamma rays, and not just the high energy neutrons, were from the deuterated acetone and not some other source sitting around the lab that was radioactive.

Taleyarkhan, R.P., Cho, J.S. et.al. Physical Review E. vol 69 pg 36109-1. The title is: 'Additional Evidence of Nuclear Emissions During Acoustic Cavitation.'

See also this blurb

Re:Doesn't mean he's *right*

[bcrowell]

Some context:

• The slashdot editors have always loved posting credulous articles about cold fusion.
• The original cold fusion experiments by Pons and Fleischman (using electrochemistry) didn't have any detectors in place to detect neutrons. In fact, if the experiment had been producing the level of power they were claiming, they'd have been dead from the neutrons.
• In the '90's, Gai et al. at Yale redid the Pons and Fleischman experiments with an array of neutron detectors, and found no excess neutrons.
• There are really only two ways of interpreting the electrochemistry experiments at this point: (1) they didn't produce fusion; or (2) there are huge, fundamental mistakes in our understanding of the hydrogen atom (e.g., there's another state whose energy is lower than the normal ground state's).

Re:Doesn't mean he's *right*

[radtea]

... and also not all fusion reactions create neutrons.

This is not quite correct, especially in the context of fusion in the solid state.

It is true that considered in complete isolation from everything else, the reaction d + d -> 4He is neutron free. But considered in complete isolation from everything else a great many things are true. For example, it is true that considered in complete isolation from everything else, you can drive your car the wrong way down a one-way street and not suffer any collisions. But I doubt that would stand up in court as a justification for claiming that driving your car the wrong way down a one-way street is perfectly safe.

In the case of fusion, for d + d -> 4He to occur, d + d -> 3He + n must also occur. And when d + d -> 4He occurs, the alpha particle carries off about 23 MeV, if memory serves. This is quite far above the neutron binding energy of most nuclei, which means that nuclear collisions as the alpha particle slows down can knock neutrons free. And such collisions produce a lot of gamma rays, too.

Believers in cold fusion are required to make up phenomena that might suppress these and other neutron and gamma production processes. Unfortunately, those phenomena always contradict what we know about solid state and nuclear physics. And by "know" I don't mean just "what we have a good theoretical understanding of" but also "what we are empirically certain of."

Finally, I'd like to point out a trivial falsehood in your post:

Well, 40 years ago "high temperature" super conduction was physically impossible. If a scientist had claimed super conduction does exist on high temperatures as well, his colleagues had declared him mad.

On the contrary, when a scientist actually did claim that super conduction exists at high temperatures his colleagues first reproduced the results and then gave him a Nobel Prize. That's what scientists do when people find the unexpected--try to reproduce the results, and if they do, reward the discoverer. No matter how astonishing and unexpected the results are. It is only when people make improbable claims with insufficient evidence that the question of their sanity is raised.

"another scientist"

[forringer]

Well, I am that "other scientist." It is nice to see good press for bubble fusion reach slashdot (no, I didn't submit it.)

First, I agree with the previous posters that this is not "cold fusion." The centers of the collapsing bubbles are very hot. Apparently hot enough to cause fusion.

The research I published was based on experiments conducted at Purdue University using a setup provided by Dr. Taleyarkhan. All equipment calibration, measurements, and data analysis were preformed by me and my students. We had full access to the equipment and we were very careful to make sure that there was nothing to contaminate our data.

People who have read the actual paper (Transactions of the American Nuclear Society, vol 95, p 736) would agree that the results published leave no room for doubt that the neutrons are caused by the collapsing bubbles in a deuterated fluid - the appropriate control experiments were performed - the statistics are significant.

The controversy comes because several well respected and talented physicists have not been able to reproduce Dr. Taleyarkhan's results in their own labs. This has led several people (including an editor from Nature Magazine) to conclude that Dr. Taleyarkhan must be faking his data.

I cannot explain why it has been so hard to reproduce the results in another lab except to say that null results are pretty easy to get in any sensitive experiment and it originally took Dr. Taleyarkhan several years to perfect his methods.

I suspect that all that is needed is a little more time and we will hear about several labs who have confirmed this work completely independently. Of course we are working on that very thing here at LeTourneau University.

Even if it takes some time to reproduce the results at another lab, having independent researchers come to Purdue and reproduce the experiments should be a big step in moving past the controversy.

Respectfully,
Dr. Ted Forringer
Assistant Professor of Physics
LeTourneau University

Re:"another scientist"

[forringer]

(sorry, I have fixed the formatting in the previous post)

> how close does this reaction come to break-even?

Lets see ... we put about 10 watts of power in and got something less than 10,000 neutrons/second out. At 2.5 MeV per neutron, that is about 4e-9 Watts out.

So, not close.

> Does it look like the apparatus could be modified
> to pass this point (i.e. is the limitation based > on physics or engineering)?"

There is no physics limitation that I know of - it looks like a (hard) engineering question.

Respectfully,
Ted Forringer