I agree with what you say, but not that this makes a collectively stronger for a common nuclear origin because by definition positive LENR results are those that imply nuclear origin and therefore they are looked for (by these experiments). Any such anomaly counts as positive - any negative (no anomaly) does not count as negative. Because exactly what anomaly is expected in any individual case is not predicted by LENR. Anyway - I understand that weighting this is complex and can be argued both ways.
That is a worthwhile point. It is true that a single killer experiment would be powerful. But not overwhelmingly so. Scientists rightly never believe single experiments. They get very interested in them, try to reproduce, try to work out theory that could be compatible with the new evidence. You can see that with the FTL neutrino experiment. Equally when the result is not predicted by any otherwise plausible theory they are rightly very cautious about its being real. As indeed the FTL experiment - so carefully checked before publication - turned out not to be real.
The point about reproduction is not just "reproduce exactly the anomaly". It is that as soon as an anomaly is reproducible you can test it in different ways and ask questions about it. That can quickly provide hints as to its origin which may be an unknown experimental artifact, or an unknown law of physics.
The biggest credibility problems for LENR is the large amount of "could be LENR" evidence. That sounds strange! It has two aspects:
(1) (this is unfair - and I agree with people here that it was until team google unfairly discriminated against) the surge of interest a long time ago with no conclusive results, nor plausible theory makes people think now "more of the same" and be overly dismissive.
(2) (this is fair). The more diverse poorly attested anomalies are quoted seriously as LENR the more it looks like a pseudoscience. The Rossi phenomenon. those free energy companies that have claimed commercial results for 20 years, yet whose demos are different over time and rely on ever more complex and uncertain measurements. People who look at the may wonderful not understood phenomena such as ball lightning and hypothesise that is cause by LENR. People who claim a very wide range of transmutations from uncertain experiments. This diverse evidence makes fitting a predictive theory incredibly difficult. For example, it has to be, almost any nuclear transformation can happen, in LENR experiments, while such has never been observed by those not looking for LENR, and the energy mismatch fractionation problem is uniformly solved meaning that expected and very easily measurable high energy porducts are not observed.
(2) is why I am more positive about electrolysis D+D LENR than other things. Even opening it to H+H as well as D+D reduces its credibility (not to zero - but it becomes less attractive) from my POV.
These ideas are I think not ones you can engage with unless you have a truly open mind. They relate to real uncertainty, and weighting the probability of different explanations. They do not prove LENR does not exist, they affect high likely it is to exist. And that judgement is so subjective that I don't see any scientific way it can be resolved, except in a positive way from new evidence. So I do not see LENR can ever be disproved. However, specific LENR theories - e.g. Widom Larsen - can be checked and proved or disproved. The more definite the theory the more it can be disproved. If the theory has steps where the rationale is hand waving it will be more difficult to disprove because you can reasonably posit many different mechanisms and fit whatever results occur to some variant.
Agreed. Although post-team-google this argument applies less. TG had decent funding, and tried hard to find a reproducible "define LENR" experiment. Their work showed some anomalies that were interesting and are still being actively pursued. It is always a judgement call where do you throw money: e.g. LENR or experiments that might test modified GR theories, or deliver info on neutrinos.
The high quality post-F&P work showed results much lower than FP claimed, and to that extent invalidates their claims. You have a credibility problem if you say that both F&P claims and McKubre claims are correct, since the later experiments, with more accurate calorimetry, shows lower results than the original F&P experiments with less accurate calorimetry. Most people, looking at those experiments, would say that if LENR is real either F&P had green fingers never repeated after or F&P's claims were over-egging things a lot. Scientists tend not to believe in green fingers.
The credible modern experiments do not replicate the most interesting (but not replicable) "good quality" post-F&P results. E.g the McKubre series that has one (?) result with much higher excess heat - clearly beyond possible errors - than the others. Ed's very creditable attempts to find a "lab rat" electrolytic experiment with clear excess heat show very low excess heat results. At a level most external observers would not call certain. Those modern experiments replicate low uncertain levels of excess heat. It is frustrating - it means we must stay interested in the phenomena without thinking of it has strong evidence for LENR.
The one negative from this is hard to quantify. Any level of real nuclear excess heat should - you would expect from every plausible mechanism - be highly variable and often muhc higher than measurement errors so with effort you would expect it to be possible to find a lab rat experiment that shows it clearly. There are challenges to this - such a variable mechanism can destroy NAEs as soon as they become active etc. But it is unlikely that consistent excess heat over a long time can only be found at levels that are so low compared with experimental error. I remind you of the first sentence in this paragraph. This is a genuine argument - but it is hard to quantify its weight. Personally I vacillate - sometimes I think it has ahigh weight, sometimes low. It is ok to be uncertain.
True. But then none of us are qualified to make rigorous critiques of these experiments. Those who are (Ed?) are subject inevitably to the exact group think that those who believe LENR is clearly real think afflicts the rest of the scientific establishment.
What would be needed to find non-LENR reasons for the anomalies is intense interest from many highly qualified who were trying hard to disprove LENR. A sort of anti-team-google. You can see easily that no-one serious would ever want to do that. You can however be sure that LENR would get that interest when it finds a lab rat experiment with certain results. those people would be piling in trying to identify the (obvious) anomaly and equally happy whether they were proving LENR or proving some boring non-LENR error mechanism.
