Fusion In Sonoluminescence (Again)?

srhuston writes "According to a story at the NY Times (first born child req'd, yadda yadda), 'Scientists are again claiming they have made a Sun in a jar, offering perhaps a revolutionary energy source, and this time even some skeptics find the evidence intriguing enough to call for a closer look.' This has been covered here before (First, second, third) but it looks like they claim that the latest round of experiments, using better detectors, 'offer more convincing data that the phenomenon is real'." The scientists involved come from Rensselaer Polytechnic Institute, Purdue University, Oak Ridge National Laboratory, and the Russian Academy of Science; here's their press release.

Comments

reaim your horseshoes

[Doc Ruby]

An order of magnitude too low is also within merely one order of magnitude of success. What actual quantity was in the range? Degrees Kelvin? Joules:m^3? Order of *decimal* magnitude, logarithmic, other? In a statistically distributed energy system, an average miss by 0.1% might mask hits in 1% of the material, balanced by farther misses in the other 99%. And if you were really only 33% off, considering a 2-3x error margin, might their experiment not have been more precise in efficiency, and in measurement, offering a hit at the threshold?

When fusion is industrialized, I expect that some processes will far exceed the fusion thresholds, for their own specific reasons. The threshold is not a bullseye, but rather a welcoming shore of a virgin territory. News of our drawing ever nearer is tantalizing, but not discouraging, as we prepare to colonize the territory.

Re:Energy

[Doubting Thomas]

> The amount of energy invested in the system will have to be exceeded by the energy produced or else it is for naught.

Perhaps not in this case, but that is not generally the correct litmus test for the viability of a power source.

Portability matters. Batteries are horribly inefficient, yet they seem to keep me from stumbling around in the woods at night quite nicely. Similarly, the photovoltaics on a satellite, or on a water pump in rural Bangledesh, may take far more power to create than they will ever produce, and yet they are useful because we can't run an extension cord up to geosynchronous orbit, or run power lines for hundreds of miles through sparsely populated territories, (especially where the scrap metal value of the powerlines exceeds the yearly income potential of the local population, but that's an economic issue, not a matter of physics).

Now, given the comparative simplicity of the current prototypes, it's probably safe to say that the power input required to create the device is not a limiting factor. However, for arguments sake, let's say that a working design which sustains the reaction may well require a more precise fusion chamber, made of specific materials machined to tight tolerances, and perhaps involving active electronic control. All of these involve great expenditures of energy, to mine the materials, refine them, and produce the finished product. Could it be used to power our cities? Of course not. And yet, that product could still be the most efficient (well-to-wheel, so to speak) portable power source ever built. That alone would make the effort worthwhile.