Scientific low points: (2)

The second major low point from recent times is polywater. The history of polywater is brief and not particularly distinguished. Nikolai Fedyakin condensed water in, or repeatedly forced water through, quartz capillaries, and found that tiny traces of such water could be obtained that had an elevated boiling point, a depressed freezing point, and a viscosity approaching that of a syrup. Boris Deryagin improved production techniques (although he never produced more than very small amounts) and determined a freezing point of – 40 oC, a boiling point of » 150 oC, and a density of 1.1-1.2. Deryagin decided there were only two possible reasons for this anomalous behaviour: (a) the water had dissolved quartz, (b) the water had polymerized. Everybody “knew” water did not dissolve quartz, therefore it must have polymerized. From the vibrational spectrum of polywater, two new bands were observed at 1600 and 1400 cm-1. From force constant considerations this was explained in terms of each OH bond being of approximately 2/3 bond order. The spectrum was consistent with the water occurring in hexagonal planar units, and if so, the stabilization per water molecule was calculated to be in the order of 250-420 kJ/mol. For the benefit of the non-chemist, this is a massive change in energy, and it meant the water molecules were joined together with a strength comparable to the carbon – carbon bonds in diamonds. The fact that it had a reported boiling point of » 150 oC should have warned them that this had to be wrong, but when a bandwagon starts rolling, everyone wants to jump aboard without stopping to think. An NMR spectrum of polywater gave a broad, low intensity signal approximately 300 Hz from the main proton signal, which meant that either a new species had formed, or there was a significant impurity present. (This would have been a good time to check for impurities.) The first calculation employing “reliable” methodology involved ab initio SCF LCAO methodology, and water polymers were found to be stabilized by polymer size. The cyclic tetramer was stabilized by 177 kJ/mol, the cyclic pentamer by 244 kJ/mol, and the hexamer by 301.5 kJ/mol. One of the authors of this paper was John Pople, who went on to get a Nobel prize, although not for this little effort.

All of this drew incredible attention. It was even predicted that an escape of polywater into the environment could catalytically convert the Earth’s oceans into polywater, thus extinguishing life, and that this had happened on Venus. We had to be careful! Much funding was devoted to polywater, even from the US navy, who apparently saw significant defence applications. (One can only imagine the trapping of enemy submarines in a polymeric syrup, prior to extinguishing all life on Earth!)

It took a while for this to fall over. Pity one poor PhD candidate who had to prepare polywater, and all he could prepare was solutions of silica. His supervisor told him to try harder. Then, suddenly, polywater died. Someone notice the infrared spectrum quoted above bore a striking resemblance to that of sweat. Oops.

However if the experimentalists did not shine, theory was extraordinarily dim. First, the same methods in different hands produced a very wide range of results with no explanation of why the results differed, although of course none of them concluded there was no polywater. If there were no differences in the implied physics between methods that gave such differing results, then the calculation method was not physical. If there were differences in the physics, then these should have been clearly explained. One problem was, as with only too many calculations in chemical theory, the inherent physical relationships are never defined in the papers. It was almost amusing to see, when it was clear there was no polywater, a paper was published in which ab initio LCAO SCF calculations with Slater-type orbitals provide evidence against previous calculations supporting polywater. The planar symmetrical structure was found to be not stable. A tetrahedral structure made by four water molecules results in instability because of excessive deformation of bond angles. What does that mean, apart from face-covering for the methodology? If you cannot have roing structures when the bond angles are tetrahedral, sugar is therefore an impossible molecule. While there are health issues with sugar, impossibility of its existence is not in debate.

One problem with the theory was that molecular orbital theory was used to verify large delocalization of electron motion over the polymers. The problem is, MO theory assumes it in the first place. Verifying what you assume is one of the big naughties pointed out by Aristotle, and you would thing that after 2,400 years, something might have stuck. Part of the problem was that nobody could question any of these computations because nobody had any idea of what the assumed inputs and code were. We might also note that the more extreme of these claims tended to end up in what many would claim to be the most reputable of journals.

There were two major fall-outs from this. Anything that could be vaguely related to polywater was avoided. This has almost certainly done much to retard examination of close ordering on surfaces, or on very thin sections, which, of course, are of extreme importance to biochemistry. There is no doubt whatsoever that reproducible effects were produced in small capillaries. Water at normal temperatures and pressures does not dissolve quartz (try boiling a lump of quartz in water for however long) so why did it do so in small capillaries? The second was that suddenly journals became far more conservative. The referees now felt it was their God-given duty to ensure that another polywater did not see the light of day. This is not to say that the referee does not have a role, but it should not be to decide arbitrarily what is true and what is false, particularly on no better grounds than, “I don’t think this is right”. A new theory may not be true, but it may still add something.

Perhaps the most unfortunate fallout was to the career of Deryagin. Here was a scientist who was more capable than many of his detractors, but who made an unfortunate mistake. The price he paid in the eyes of his detractors seems out of all proportion to the failing. His detractors may well point out that they never made such a mistake. That might be true, but what did they make? Meanwhile, Pople, whose mistake was far worse, went on to win a Nobel Prize for developing molecular orbital theory and developing a cult following about it. Then there is the question, why avoid studying water in monolayers or bilayers? If it can dissolve quartz, it has some very weird properties, and understanding these monolayers and bilayers is surely critical if we want to understand enzymes and many biochemical and medical problems. In my opinion, the real failures here come from the crowd, who merely want to be comfortable. Understanding takes effort, and effort is often uncomfortable.

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Scientific low points: (1)

A question that should be asked more often is, do scientists make mistakes? Of course they do. The good news, however, is that when it comes to measuring something, they tend to be meticulous, and published measurements are usually correct, or, if they matter, they are soon found out if they are wrong. There are a number of papers, of course, where the findings are complicated and not very important, and these could well go for a long time, be wrong, and nobody would know. The point is also, nobody would care.

On the other hand, are the interpretations of experimental work correct? History is littered with examples of where the interpretations that were popular at the time are now considered a little laughable. Once upon a time, and it really was a long time ago, I did a post doctoral fellowship at The University, Southampton, and towards the end of the year I was informed that I was required to write a light-hearted or amusing article for a journal that would come out next year. (I may have had one put over me in this respect because I did not see the other post docs doing much.) Anyway, I elected to comply, and wrote an article called Famous Fatuous Failures.

As it happened, this article hardly became famous, but it was something of a fatuous failure. The problem was, I finished writing it a little before I left the country, and an editor got hold of it. In those days you wrote with pen on paper, unless you owned a typewriter, but when you are travelling from country to country, you tend to travel light, and a typewriter is not light. Anyway, the editor decided my spelling of a two French scientists’ names (Berthollet and Berthelot) was terrible and it was “obviously” one scientist. The net result was there was a section where there was a bitter argument, with one of them arguing with himself. But leaving that aside, I had found that science was continually “correcting” itself, but not always correctly.

An example that many will have heard of is phlogiston. This was a weightless substance that metals and carbon gave off to air, and in one version, such phlogisticated air was attracted to and stuck to metals to form a calx. This theory got rubbished by Lavoisier, who showed that the so-called calxes were combinations of the metal with oxygen, which was part of the air. A great advance? That is debatable. The main contribution of Lavoisier was he invented the analytical balance, and he decided this was so accurate there would be nothing that was “weightless”. There was no weight for phlogiston therefore it did not exist. If you think of this, if you replace the word “phlogiston” with “electron” you have an essential description of the chemical ionic bond, and how do you weigh an electron? Of course there were other versions of the phlogiston theory, but getting rid of that version may we’ll have held chemistry back for quite some time.

Have we improved? I should add that many of my cited failures were in not recognizing, or even worse, not accepting truth when shown. There are numerous examples where past scientists almost got there, but then somehow found a reason to get it wrong. Does that happen now? Since 1970, apart from cosmic inflation, as far as I can tell there have been no substantially new theoretical advances, although of course there have been many extensions of previous work. However, that may merely mean that some new truths have been uncovered, but nobody believes them so we know nothing of them. However, there have been two serious bloopers.

The first was “cold fusion”. Martin Fleischmann, a world-leading electrochemist, and Stanley Pons decided that if deuterium was electrolyzed under appropriate conditions you could get nuclear fusion. They did a range of experiments with palladium electrodes, which would strongly adsorb the deuterium, and sometimes they got unexplained but significant temperature rises. Thus they claimed they got nuclear fusion at room temperature. They also claimed to get helium and neutrons. The problem with this experiment was that they themselves admitted that whatever it was only worked occasionally; at other times, the only heat generated corresponded to the electrical power input. Worse, even when it worked, it would be for only so long, and that electrode would never do it again, which is perhaps a sign that there was some sort of impurity in their palladium that gave the heat from some additional chemical reaction.

What happened next was nobody could repeat their results. The problem then was that being unable to repeat a result when it is erratic at best may mean very little, other than, perhaps, better electrodes did not have the impurity. Also, the heat they got raised the temperature of their solutions from thirty to fifty degrees Centigrade. That would mean that at best, very few actual nuclei fused. Eventually, it was decided that while something might have happened, it was not nuclear fusion because nobody could get the required neutrons. That in turn is not entirely logical. The problem is that fusion should not occur because there was no obvious way to overcome the Coulomb repulsion between nuclei, and it required palladium to do “something magic”. If in fact palladium could do that, it follows that the repulsion energy is not overcome by impact force. If there were some other way to overcome the repulsive force, there is no reason why the nuclei would not form 4He, because that is far more stable than 3He, and if so, there would be no neutrons. Of course I do not believe palladium would overcome that electrical repulsion, so there would be no fusion possible.

Interestingly, the chemists who did this experiment and believed it would work protected themselves with a safety shield of Perspex. The physicists decided it had no show, but they protected themselves with massive lead shielding. They knew what neutrons were. All in all, a rather sad ending to the career of a genuinely skillful electrochemist.

More to follow.

Climate Change Horrors

By now a lot of people are probably getting sick of hearing about climate change, but it needs to be continuously emphasized because the problem is not going away any time soon. People are now starting to realize that global warming means stronger storms, but that is the least of our problems. Worse than that, most people don’t actually know what many of our problems are going to be. Let us forget about storms and look at what else could happen.

The most frightening is if warming gets out of control and melts the Arctic tundras. We have to be careful about this, but we know that about 252 million years ago there was the most massive mass extinction ever. What happened? We cannot be entirely sure, but one account has it that global warming of about four degrees caused the release of Arctic methane, and 97% of life on Earth died. Now, of course we cannot be sure of what happened and the Earth is not like what it was then. The continents are not even the same, and those land forms that were there then are not in the same place now. Nevertheless, we can be sure that if the Arctic methane is released due to warming, there will be a very serious enhancing of temperature. Amongst other things, for the first two decades methane is 87 times worse than carbon dioxide.

The most obvious consequence is from the heat. Already there are parts of the world where heat becomes a problem for people working, and this is not helped by humidity increases. In 2003 there was a European heat wave that killed as many as 2000 people every day it maintained its high temperatures. If we add 2 degrees to the average temperatures, cities in the middle east, like Bahrain, and further east like Karachi and Kolkata will be almost uninhabitable, and for Muslims, the hajj would be impossible. We could try air conditioning, but with what fuel? Our current energy systems would simply add to the problem.

Warming of agricultural areas reduces crop yields. At present, most crops are grown in as near ideal conditions for them, and most foods are produced in quantities to feed the population, but not with a huge excess. So the biggest problem is starvation. You may say, move the agriculture away from the equator to newly warmed regions. That is possible to some extent, but what we forget is that the current colder regions do not have good soil. Trying to grow crops in Greenland is fine, until you discover that most of the newly exposed surface is stone.

There are also secondary issues, thus the recent flooding in Bangla Desh that covered almost half the country with water also largely destroyed the crops being grown there. Other places may suffer droughts, with the same result. My view is this is uncertain, because I do not believe that modeling is good enough. You will hear that in Jurassic times temperatures were significantly warmer than now. Yes, but much of the land was desert, the continents were also in a greatly different configuration, and mammals were not predominant.

Everyone now knows that as the ice melts, the sea levels will rise. Depending on how much ice melts, the seas could rise by seventy meters. At present, about 600 million live within ten meters of sea level. Given that even modest sea level rising predicts a seven to fourteen meter rise, you can see that an awful lot of infrastructure will have to be rebuilt, and perhaps a billion people moved and rehoused, followed by somehow finding them employment. That means more carbon dioxide emissions. Cement manufacture alone produces about three billion tonne of carbon dioxide per annum now, and if we have to rebuild the entire coastal infrastructure, a huge amount of additional cement will be required. If the sea absorbs too much carbon dioxide, and a lot of organic matter gets trapped in it, parts may go anoxic and emit large amounts of hydrogen sulphide. Excessive hydrogen sulphide is the agent that is believed to have enhanced the great extinction in the late Permian. Higher levels of carbon dioxide are often used to explain coral bleaching, but the problem is much worse. Shellfish that depend on aragonite, one of the two crystalline forms of calcium carbonate, will not be able to form shells if the oceans absorb significantly more carbon dioxide because aragonite will no longer crystallise.

The removal of ice from the poles will also alter weather patterns. Wind changes may lead to greater air pollution in certain areas if we try to maintain current industries. China has recently suffered from this. Places that are now livable will become desert, or near desert, and this will force people to move. The problem, is, where to? Where will they get work? Which countries are going to accept them, particularly bearing in mind the numbers also displaced from the shores? With few options, various wars are more likely to break out. Unless we solve the energy crisis, what next? If we stop burning fossil fuels, how will our economies progress? The real driver of economic growth since the mid 19th century has been cheap energy from fossil fuels. However, if we do not stop such burning, and if we do not find alternatives, GDP will drop significantly, which will make it more difficult for a large fraction of the population to earn a living. To survive, one outcome is enhanced war and a proliferation of crime.

Scary? Hopefully these consequences are sufficient to persuade those in power to do a lot. I am far from convinced that current politicians recognize what the problem even is, let alone how to address it.

Hurricanes Harvey, Irma, What next?

By now just about everybody on the planet will have heard of Hurricane Harvey, and we all feel deeply sympathetic to the people of Houston. This was a dreadful time for them, which raises the question, why did this happen? As the disaster abates, the words “Global Warming” keep coming up. Global warming did not cause that Hurricane, it did not cause it to land on Houston, and with one reservation, it almost certainly did not cause hurricanes to be more common. However, global warming would have made the ocean a little warmer than usual, and that will have increased the intensity of any hurricane that was generated, made it more expansive, and more powerful. While it might have been the most newsworthy event, it was by no means the worst event attributable to an effect of global warming.

Hurricanes and Typhoons are just local names for tropical cyclones, and they originate because the earth is a rotating sphere, and because surface temperatures are uneven, therefore in places air rises because it is warmer, and in other places it falls. In the former you get low pressure, while in the latter, high pressure, and because there are pressure differentials, air flows towards and away from these systems respectively. Air moving in the north-south directions has different velocities in the east-west directions because of the different rotational velocities, and this generates some circular air motion (the Coriolis force) the direction depending on whether the air is being sucked in or being pushed out. In the normal course of events this would generate modest circulation, which would affect nobody badly.

However, there is an additional aspect. When the circulation goes over water, it evaporates moisture, and when this is sucked upwards in a low pressure event, eventually the air gets colder and the water comes out as water droplets, which generate clouds, and if there is enough moisture, rain. Of course, this is somewhat oversimplified, especially in mid-latitudes where you get fronts, etc, to complicate matters as air at different temperatures starts to mix, but the above, while oversimplified, at least lets us see what happened with Harvey. The reason the tropical storms are so bad, when you get away from the equator so as to get some effect from the Coriolis effect, is that the warmer the water, the more moisture gets sucked up. Water has a rather high latent heat of evaporation, so when it condenses out, that energy has to go somewhere. The warmer air rises, generating lower pressures below, and hence more suction, which means more water sucked up, leading to even more air being sucked in, leading to the extremes of rotational kinetic energy that we see.

So, the warmer the water, the more energy is available to power stronger winds, and more rain comes down. Harvey was particularly bad because it stalled over Houston. Normally, tropical cyclones run out of strength as they cross land, because there is no further moisture to power them, but Harvey had half of itself over land, and half over the Gulf of Mexico, so it was able to keep itself going longer than you might expect. So the hurricane would have been a little stronger than without the global warming, it would have dropped much more rain than without the global warming, but its path greatly accentuated the damage. Irma will do the same wherever it hits.

What global warming will also do is increase the number of tropical cyclones around the world. That is simply because by increasing the surface temperatures of the seas, there is more energy available for a weather event, hence more of the systems that would normally just qualify as storms or cyclones get upgraded to the tropical cyclone status. Worse, they do not have to be in the tropics. In Wellington, where I live, this winter the Tasman was 1.5 degrees C hotter than usual for this time of the year, and when a resultant system somehow met some colder sub Antarctic air, we got a storm with wind speeds that qualified for a category 3 hurricane, with a lot of rain, but it was cold. So, what we can expect in the future is many more of these storms, and not just in the tropics. The storms do not need to be hot; they merely need to have been powered initially with warmer seawater.

I mentioned that Harvey was not the worst event. At the same time, the monsoon over parts of India and Bangla Desh, thanks to increased sea temperatures, gave record rainfall that put about half the country under water, thus probably wiping out a large fraction of the country’s crops. It also killed about twelve hundred people and severely affected the lives of forty-one million people. And Bangla Desh in one of the poorest countries on the planet. There may be a tendency to think Houston, being part of the richest country on the planet, will get over this, and it probably will, but these changing events are going to happen everywhere, and as with Bangla Desh, many places will not be able to cope easily. It is the richer countries that have to start doing things to control these disasters, if for no other reason than they are the only ones with the means to make an impact. We really need to work out how to deal with such events, because they will occur, but better still, we need to take real action to minimize the number that do happen, and that means really doing something about global warming. Those who deny its existence should be made to exchange positions with people in Bangla Desh