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Physics A-Level

Error in a scientific paper: here's what I did

6/19/2019

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“Say, doesn’t that look remarkably similar to something else that I saw…”

Compiling data for a scientific publication is challenging. What to include and exclude is a tacit consideration for every scientist. Before you might get angry that scientists are ‘fiddling with the data’ or ‘only showing you what they want’, please consider the following: you yourself are an information gathering and filtering machine. In fact, you harvest information involuntarily all the time. However, your evolutionary self has learnt to filter and select information and pitch it according to your need. When you walk in to a room you don’t actively notice that the walls are flat or that you are wearing shoes; but if the walls were to spontaneously turn green or your shoes disappear, you’d notice it right away. Is that a fire on my desk?!

When a scientist presents data, we hope they do so openly and honestly, and normally expect a broad overview to guide the reader as to where this data should be placed in the grand scheme of things. There will inevitably be an element of self-selection in any scientist’s data; this is unavoidable and yet totally understandable. Include everything and any scientific work will become unreadable, boring and uninformative. Include too little and you run the risk of not making your point clear enough. Finding that balance is an art-form. The peer review process aspires to produce a higher publication standard. In reality, it can only do so up to a certain point. However, once a publication is out there in cyber space, the general public can always weigh in to scrutinize its finer details. Which brings me to the purpose of this post...

I recently noticed a peculiarity in a scientific paper *. I initially identified it as an error, because I had seen exactly the same graph elsewhere. After a quick check of the old publication, I noticed that these ‘new’ data points were exactly the same as the old ones, although they were coloured differently, the x-axis scale was changed and some of the data points were missing. See for yourselves:

Picture
The data in question. The x-axis is different and yet the data looks the same... although with different colours and some points are missing... (I've expanded part of the data with a dotted box, for clarity)
Above are two graphs (1 and 2) from two different publications on different years (I’ve made enlarged dotted boxes for clarity). Interestingly, the publications had some shared authors, some of whom (lets say) weren’t strangers to high profile journal publications. Without going in to the details of what the graphs show, it seemed reasonable that the data was a copy. Given the curious nature of the data, I decided to contact the editor of the journal; especially since changing the x-axis scale could have implications for the interpretation of the data. This wasn't a malicious attack on those authors, it could very well have been an oversight, which it fine. But in the interest of integrity, it was worth at least asking.

Scientists are routinely reminded of the importance of the expected high standards required for publication. For a good reason: to uphold the integrity of skeptical inquiry. I remember attending a lecture on exactly such a topic from the editor-in-chief of one scientific journal, and the message was crystal clear: “no issue is too small, let us know if you have a query”. So that’s what I did.

After some routine preamble to the editor, I signed off my email “… the data looks similar, including the noise, although the x-axis scale differs. I thought it important to point this out.” I was a little nervous because I wanted to maintain anonymity (which they do categorically adhere to). But, being the coy inquirer that I am, I at least wanted someone to check this data anomaly without it being seen as a personal attack on the authors. I can confidently say that the editor's response (up until the eventual correction) was very professional and reassuring.
 
In one back and forth, the journal editor responded thusly: “… thank you for bringing to our attention this discrepancy. We believe _*journal*_ should be of the highest order of rigor and greatly appreciate people who carefully read our work and call to our attention these issues. If you have any further questions… once again, I want to give you a sincere thank you for giving this manuscript such a careful reading to find this error and bringing it to our attention.”

A few short months later both journals published corrections and the world is a better place.
 
After note: I would highly encourage any reader of science to be involved in the material that you read (which you undoubtedly do already!). Interact with it somehow. Whether it’s a scientific journal or a newspaper article, many authors are only a click away. Ask them something whether you agree or disagree, or just want clarification. Sometimes when you dig you’ll find enlightenment and a shining ray of optimism. Other times you may find sheer malevolence (honestly) and a stark peak through a door that someone didn’t realise was left ajar **. Either way, there's a chance you could learn something, and that’s not such a bad proposition.


* if you would like to know which articles these are please PM me
** a follow up post on malevolent responses to some past inquiries will be sure to follow shortly
2 Comments

Cold Fusers Beware: DANGEROUS EXPERIMENTS AHEAD

6/10/2019

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Picturea HOT-fusion Tokamak of the Joint European Torus (JET) project. Within this chamber plasma swirls at near light speed, causing nuclei to fuse.
If, when conducting a table-top experiment, sometimes “part of it vapourised” and at other times the “contents and a part of the fume cupboard housing the experiment were destroyed”, you should probably proceed with extreme caution (but proceed you must!). These words hail from a famous publication by electrochemists Martin Fleischmann and Stanley Pons in 1989 entitled "Electrochemically induced nuclear fusion of deuterium". In it, they detail the holy grail of energy production – nuclear fusion – and they claimed to be able to do it ‘cold’.

The importance of such a result would be colossal. Being able to generate more energy than you input would be our golden ticket to unleash energy sustainability. The end of energy scarcity as we know it. With abundant energy on tap we’re talking about global clean drinking water, emission free energy resources, electricity for all of humanity and interstellar travel…

So why has so little progress been made since the Fleischmann-Pons experiments in 1989? In truth, many attempts have since been made to repeat the experiments but, unfortunately for us all, no one has succeeded in making cold fusion work. Ever since 1989, there has been a heated debate among scientists, mostly consisting of a swathe of scathing reports against Fleischmann and Pons and their methods. Countless scientific bodies, institutes, research councils, research journals and even government agencies all weighed in on the issue. Suffice it to say, that although the claim of cold fusion was an extremely hard pill to swallow, at the end of the day it didn’t in fact meet the expected verification criteria of any new found technology; especially something as groundbreaking as cold fusion. And so, for years, cold-fusion has been relegated to the dustbin of science history.

Any mention of cold fusion, has since met with heightened skepticism and a fear of academic suicide. Which makes the new publication on cold fusion, in the journal Nature, all the more remarkable. Motivated by “the possibility that such judgement might have been premature”, they “embarked on a multi-institution programme to re-evaluate cold fusion to a high standard of scientific rigour”. Although their final results are essentially null, it highlights a key component to scientific discovery: don’t be too quick to disqualify new ideas, since you don’t know where they might lead. Although the results of the Nature paper didn’t give us cold fusion, they propose a number of exciting areas of research, derived from their work, that could very well have a high impact in other areas of research, like materials science. But in 1989, in the wake of these experiments, the case went cold…
 
What was the cold fusion that Fleischmann and Pons tried to achieve? Here is a very brief introduction of what ‘hot fusion’ (or just… ‘fusion’) is, to drive the point home about why cold-fusion would be so remarkable:
 
Fusion is a nuclear reaction whereby two small nuclei fuse, forming a larger nucleus. The initial nuclei are often positively charged, strongly repelling each other. However, when those nuclei are close enough, electrostatic repulsion gets overcome by the attracting 'strong nuclear force', which causes those nuclei to fuse together. This releases a huge amount of energy. But bringing nuclei together (especially two positively charged ones) is by no means a simple task. It does occur in our Sun constantly: hydrogen fuses to form heavier elements, releasing light and heat. However, the processes governing fusion of elements in the Sun are driven by the large amounts of pressure and heat causing those nuclei to fuse. Attempts to replicate hot-fusion, on Earth, are normally done by accelerating a magnetically confined plasma (e.g. Tokamak *) or with electromagnetic heating or particle beams, and more. Unfortunately, it requires so much energy to bring about fusion in these Earth-based instruments that it far exceeds the energy released by the fusion reaction itself! Only once the energy output is greater than the energy input, can we really start talking about the usefulness of fusion energy.
 
Enter… cold fusion. Cold fusion claims to release a measurable amount of energy without having to heat your nuclei to extremely high temperatures and pressures. The original experiments in 1989 attempted to dissolve a high concentration of deuterium (which is a hydrogen atom (i.e. a proton) packed with an extra neutron) in to a palladium electrode. The concentration being so high, that hydrogen nuclei within the solid lattice actually come energetically closer to one another than in a lattice of solid hydrogen; assisted by counterbalancing of charges from electrons as well. Fleischmann and Pons used this idea in an electrolytic cell, and found that their electrical power output was greater than their electrical power input. This purportedly meant that they had liberated some energy by fusing hydrogen. Eureka! Not so fast...
 
Unfortunately, after ~3 decades of research, cold fusion claims have not materialised. The research published in 2019 in the journal Nature, however, does offers a promising perspective on ancillary issues surrounding some aspects of cold fusion. For example, loading palladium with an ‘ultra-high’ saturation of hydrogen has exhibited unique materials properties, such as phase changes in these materials. At certain hydrogen concentrations, these highly saturated materials behave in unique ways and respond differently at particular pressures and temperatures. Pushing the limit of these material properties is certainly a worthwhile endeavour, especially since they exhibit distinct, measurable characteristics that can be controlled, manipulated and predicted. Indeed, loading metals with extremely high concentrations of hydrogen may very well be a prerequisite for cold fusion but pushing the limit of hydrogen saturation may also be a promising direction to explore, in and of itself **. Simply put: no one has been able to convincingly show that such metal loading (with hydrogen) is even possible, let alone it being a precondition for the elusive ‘cold fusion’.
 
Lets not get bogged down with cold fusion though. The truth is that this study in Nature was very brave; it touched a nerve and dared to re-think old scientific ideas and perhaps most importantly, did not overstate their claims about cold fusion at all. They give a very pragmatic outlook and prospect for the future, touching upon many important areas that could really benefit from further scientific exploration; and we may just learn something as a bonus along the way.
 
One question that was put to the authors was: ‘why pursue cold fusion when it has not been proven to exist?’. The authors respond by saying: “one response is that evaluating cold fusion led our programme to study materials and phenomena that we otherwise might not have considered. We set out looking for cold fusion, and instead benefited contemporary research topics in unexpected ways.”
 
Or in the words of a modern proverb: “Shoot for the moon, even if you miss it, you’ll land among the stars.” - Norman Vincent Peale, i.e. shoot for cold fusion and who knows what you might discover...



* a few UK based Tokamak's are of note: Oxford's Tokamak Energy and a the JET partnership
** the Nature paper provides a few more exciting secondary outcomes that may also derive from cold fusion research

2 Comments

    physbot

    Theres something interesting in the ether...

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