Gravitational Waves and Gold

One of the more interesting things to be announced recently was the detection of gravitational waves that were generated by the collision of two neutron stars. What was really interesting to me was that the event was also seen by telescopes, so we know what actually caused the gravitational waves. Originally it was thought that gravitational waves would be generated by colliding black holes, but I found that to be disturbing because I thought the frequency of detection should be rather low. The reason is that I thought black holes themselves would be rather rare. As far as we can tell most galaxies contain one in their centre, but the evidence for more is rather sparse. True, they are not easy to see, but if they come into contact with gas, which is present within galaxies, the gas falling into them will give out distinct Xray signals and further, they would perturb the paths of close stars, which means, while we cannot see the black hole, if they were common, there should be some signs.

There are some signs. The star Cygnus X-1 is apparently shedding material into some unseen companion, and giving off X-rays as well as light. A similar situation occurs for the star M33-X-7, which is in the galaxy Messier 33, which in turn is 2.7 million light years away. Now obviously there will be more that we cannot see because they are not tearing stars apart, but they are still rare. Obviously, collisions would be rarer still. With all the stars in the Universe, how often do we see a collision between stars? I am unaware of any in my life. Nevertheless, there have been estimates that there are about a billion moderately sized black holes (i.e. about 15- 20 times the size of our sun) in our galaxy. However, when we probe to see how they came up with this figure, it turned out that it arose because it was obvious that you needed them to be this common to get the frequency of the detection of gravitational waves. That reasoning is somewhat circular.

How would they collide? Like other stars within the galaxy, they would travel in orbit around a galactic centre, in which case the chances of meeting are rather low. And even if they did approach, why would they collide? The problem involves the conservation of angular momentum (the same sort of thing that the skater uses to slow down the spin by sticking her arms out). When one body approaches another, assuming they are not going to directly collide (in which case there is no angular momentum in their joint system) then they follow a hyperbolic orbit around each other and end up going away from each other in the reverse of however they approached. For one to capture the other, either the systems have to spin up to conserve angular momentum, or they have to throw something out and whichever they do, orbital decay requires a mechanism to get rid of a lot of energy. Further, they cannot spin up, which is an exchange of angular momentum, without tidal interactions forcing it. Now tidal interactions work by part of one body “flowing” in response the gravity of the other. The material does not have to move a lot, but it has to be able to move, and the black hole is so dense I don’t see it is very likely, although admittedly we know nothing about what goes on inside a black hole. We do know that nothing can escape from a black hole, so the mechanism of losing energy and angular momentum by ejecting something is out.

Now that such an event has been properly assigned to the collision of two neutron stars it makes me, at least, feel that everything is far more likely to be correct. Neutron stars are what is left over from a supernova, and it is easier to see neutron stars capture each other. First, neutron stars are made from very large stars, and while these are rarer than most other types of star, sometimes they come as double stars. That would make neutron stars close to each other, which is a start. Further, neutron stars are more likely to be deformable, and most certainly are more able to eject material into space. Neutron stars are really only held together by their intense gravity, and as they approach each other, the gravity tends to cancel, as the approaching object pulls against the pre-existing force. If the force needed to hold the neutrons becomes insufficient, the ejection of a significant amount of material is possible. After all, nuclei with a significant number more neutrons than protons are quite unstable, and each decaying neutron gives off over 1 MeV of energy. The neutron star is effectively a huge nucleus, but is held together by intense gravity rather than the strong force.

Apparently in this collision, a huge amount of material was ejected into space, and it is argued that this sort of event is what caused the formation of the metals heavier than iron, including gold and platinum. Such atoms then get mixed with the ejecta from supernovae and the hydrogen and helium from the start of the Universe, and here we are. It is a good story. However, I wonder if it is true that that is where all the gold etc. comes from? What bothers me about that explanation is that it is argued that atoms up to iron are made in stars and supernovae, but heavier ones are not because in the clouds of the ejecta, there isn’t time for the processes we know about. In my opinion, the intense pressures of the supernova that forms the neutron star would also form heavier elements. They don’t have to be made by adding protons and neutrons, after all, the synthetic elements we make, such as element number 118, are made by colliding big nuclei together. In this context, if you see a graph of the relative occurrence of the various elements, the curve is more or less smooth. Yes, there is a bit of a peak for elements around iron, but it then decays smoothly, and I would have expected that if some were made by a totally different procedure, then their relative concentrations would lie on different curves. I guess I shall never know. I can’t see anyone taking samples from the core of a supernova any time soon.

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Trump and Agreements

My scientific background means that I tend to think that decisions should be evidence based, and be formed after analyzing the information available to whoever is making the decision. But a further point, and one I try to put into my novels, is that decisions involving human activity such as politics or confrontation should relate also to the future consequences. If you are going to make a decision that has adverse consequences, there should be the probability that beneficial ones will significantly outweigh the adverse ones. An interesting point here is that very frequently the adverse consequences can be seen fairly clearly and they are likely to happen, while the beneficial ones tend to rely on hopes. Even an act like buying something falls into this. The immediate adverse consequence is that sum of money is no longer available; the hope is the item will be beneficial. In this case you can probably guess that it will be, but on the other hand when you are young and you buy a used car you can never be sure. There can also be unforeseen adverse consequences. When I purchased my first car I had a mechanic check it out, and I knew the motor would need the piston rings replaced. I factored that into the price I offered, but when the motor was disassembled it was found that when originally assembled, someone had put a bearing in back to front, and the cranckshaft had been ground down. That was an unforeseen adverse effect, particularly on my bank balance.

Taking this to international politics, I believe that one important point is that when a country decides to enter an agreement with others, the other parties can accept that the agreement will be honoured. Doubts as to whether the agreement is worthwhile should be ironed out during the negotiations prior to the agreement being signed. In this sense, it is like a business contract. When one company signs a contract with another company, or person, each side assumes that the other will carry out its obligations. If they do not, they tend to end up in court. If there is absolutely no trust, nobody does any business, and if there is no commerce, everybody ends up the loser. Of course, every now and again someone cheats, and the other parties invariably lose. Occasionally, this can become catastrophic. A possible example of this comes from Kobe steel. Generally speaking, Japanese manufacturing has been praised for its adherence to quality control and quality management, but now it has been reported that Kobe Steel has been selling substandard steel for about a decade. Presumably not all has been substandard, but the problem with steel is that it tends to be structural and deep inside something else of considerably more value, so the ripples will go deep if these allegations are true. If so, this situation is now something of a disaster for Kobe Steel, but it would also be very bad for Japanese commerce as a whole.

It is these unforeseen issues that tend to have a lasting effect, but worse is when one side properly follows its obligations and the other side simply refuses, or decides to pull out of the agreement. The threat of pulling out of an agreement if the other side does not make more concessions is a particularly bad procedure. You get all the concessions you think you can, you agree, then after the other side has started to commit itself, you pull out and demand renegotiations. That, at the very least, leaves a bad taste.

Which brings me to President Trump. Since taking office, he has withdrawn from the Trans-Pacific Partnership (and in fairness, America had yet to sign, so he was entitled to do that), he has withdrawn from the Paris Accord, he has threatened to withdraw from the North American Free Trade Agreement, has signalled that he will withdraw from a trade pact with South Korea, and has now “decertitifed” (whatever that means) a multi-lateral agreement designed to stop Iran from developing nuclear weapons. In the latter case, international observers all agree that Iran is keeping to its side of the deal. Within the US he seems to have been trying as hard as he can to hobble Obamacare, seeing as he cannot abolish it altogether. It is as if he is a serial offender. Iran has apparently signalled to North Korea that it is a waste of time entering into an agreement with the US. Given that Kim can read smoke signals too, that is not encouraging.

Being destructive is easy. Anyone can tear up agreements. The problem then is, what happens next? Maybe Trump does not care, on the grounds that the rest of the world needs the US more than the US needs the rest of the world. I hope that is not what he is thinking, because it is not true.

Fragmenting Nations

One of the more interesting questions that have arisen lately is should a region of a country have the right to break away from the country and be independent, and if so, what are the obligations of the participants? The classic way of breaking away is to have a war. The US got its independence from Britain that way, as did Eire. Does nationhood depend on “might makes right?” It can, but surely there are other ways.

It certainly helped Kosovo, and Kosovo is of interest because it was effectively US air power and NATO forces that won the war. Clinton described the activity as “upholding our values, protecting our interests, and advancing the cause of peace”. Strictly speaking, this action had no UN Security Council approval, therefore it could be regarded as illegal, and it was described as illegal but justified. Whether the Serbs would agree is another matter, and it then becomes interesting that violating the law is fine as long as you think it is justified. Who says so? The guys with the most guns?

The background to Kosovo is of interest. Some in Kosovo wanted independence, particularly those of Albanian origin, and apparently things got out of hand when the Kosovo Liberation Army made four attacks on Serbian security people. The Serbians soon began calling the KLA terrorists (and since they carried out sneak murders, that is probably fair) while the Albanians saw them as “freedom fighters”. Up until 1998, the US government described the KLA as a terrorist group, but suddenly it changed its mind and used NATO to intervene. End of Kosovo Serbians’ hopes. US intervention had another effect: it took the Monica Lewinsky affair off the news table for President Clinton. The US used cluster bombs, and did serious damage and caused considerable civilian casualties, including to Albanians in Kosovo, but the net result was that Kosovo apparently has declared independence. However, not everyone recognizes this, and it remains to some extent under UN administration.

It would seem fair for a split if those leaving did so by winning a referendum that was fairly executed. Scotland had such a vote and decided to stay, so the issue does not arise, however I believe had the vote been yes, London would have agreed. Of course this raises the question that if they keep having votes, sooner or later they will get one result to leave, and that would be irreversible. So maybe there has to be a limit to the number or spacing of referenda.

However, votes can also be rigged in favour of some end. The vote to have a separate Kurdistan would probably win for the Kurds, but would they take Kirkuk? To make sure they would, when the Iraqi army fled from ISIS, a large number of Kurds poured into Kirkuk, and so I guess they would win a vote. But if you pour in the appropriate number of extras to win the vote, is that the right way to go? My guess is no. Then the question is, is the vote fair? When Crimea seceded from Ukraine and joined Russia, this was done with a clear majority vote favouring it, but the Russians had poured in a number of soldiers and they ran the voting system, and as a consequence a number of people do not believe it was fair. My guess is, it probably was because there were a lot of people of Russian descent there, but we cannot be sure. In Crimea, it probably was a case of “might makes right”, but if the Russian military did not come in, the Ukrainians had the might, and as can be seen in eastern Ukraine, they are prepared to use it.

Suppose we look at Catalonia. There have been widespread claims that Catalonia should be independent from Spain, and they held a referendum, which gained 90% in favour. So that is clear evidence, right? Maybe not. Spain declared the referendum illegal and sent in riot police. Those not in favour of independence may well have considered the vote illegal, and they wanted no part in it. It now turns out that only about 40% of those eligible to vote participated, so maybe this was not as conclusive as the enthusiasts claim.

The next question is, why do people want independence? Presumably because they feel they would be better off independent. The Catalans apparently are net donors (tax paid less benefits) to Madrid of about 10 billion euros. However, this might be a little misleading because there are a number of Head Offices of Spanish companies in Barcelona, so company tax from all activities in Spain would be paid from Barcelona. If Barcelona were in a separate country, presumably the activities from Spain would remain taxed by Spain. In Scotland’s case, one can’t help wondering whether the politicians had their eyes on the North Sea oil revenues. In my opinion, in such a breakup, existing royalties and such should be divided between the original members based on population, in which case the returns would be a lot less.

That leaves the Lukansk, Donbass and Donetz oblasts in Eastern Ukraine. Should they have independence? A lot of opinions in the West say yes; territorial integrity should outweigh grumpy citizens. In this case, Western Ukraine has quite different objectives; they want to join the EU while the East wants closer ties with Russia. Irrespective of the rights and wrongs of this, in my opinion there has been enough shelling and bombing of these oblasts that the citizens there will not accept the Western domination. The West complains about Russian intervention that has helped the Eastern Ukrainians. In doing so, they conveniently forget Kosovo. Also, it is now very doubtful Ukraine could join the EU, and if they did, they would find EU financial impositions on Ukraine would make Greece look somewhat attractive. My guess is, Germany would not be willing to carry an even bigger load.

So, what are the conditions for breaking up? I rather fancy there is no recipe. The various places have to find their own salvation. Nothing could be worse, however, than encouraging a breakup, and leaving one part without adequate resources, or encouraging them, and then walking away after the event.

A personal scientific low point.

When I started my PhD research, I was fairly enthusiastic about the future, but I soon got disillusioned. Before my supervisor went on summer holidays, he gave me a choice of two projects. Neither were any good, and when the Head of Department saw me, he suggested (probably to keep me quiet) that I find my own project. Accordingly, I elected to enter a major controversy, namely were the wave functions of a cyclopropane ring localized (i.e., each chemical bond could be described by wave interference between a given pair of atoms, but there was no further wave interference) or were they delocalized, (i.e. the wave function representing a pair of electrons spread over more than one pair of atoms) and in particular, did they delocalize into substituents? Now, without getting too technical, I knew my supervisor had done quite a bit of work on something called the Hammett equation, which measures the effect or substituents on reactive sites, and in which, certain substituents that had different values when such delocalization was involved. If I could make the right sort of compounds, this equation would actually solve a problem.

This was not to be a fortunate project. First, my reserve synthetic method took 13 steps to get to the desired product, and while no organic synthesis gives a yield much better than 95%, one of these struggled to get over 35%, and another was not as good as desirable, which meant that I had to start with a lot of material. I did explore some shorter routes. One involved a reaction that was published in a Letter by someone who would go on to win a Nobel prize. The very key requirement to get the reaction to work was omitted in the Letter. I got a second reaction to work, but I had to order special chemicals. They turned up after I had submitted my thesis. They travelled via Hong Kong, where they got put aside and forgotten. After discovering that my supervisor was not going to provide any useful advice on chemical synthesis, he went on sabbatical, and I was on my own. After a lot of travail, I did what I had set out to do, but an unexpected problem arose. The standard compounds worked well and I got the required straight line set with minimum deviation, but for the key compound at one extreme of the line, the substituent at one end reacted quickly with the other end in the amine form. No clear result.

My supervisor made a cameo appearance before heading back to North America, where he was looking for a better paying job, and he made a suggestion, which involved reacting carboxylic acids that I already had in toluene. These had already been reported in water and aqueous alcohol, but the slope of the line was too shallow to be conclusive. What the toluene did was to greatly amplify the effect. The results were clear: there was no delocalization.

The next problem was the controversy was settling down, and the general consensus that there was such delocalization. This was based on one main observational fact, namely adjacent positive charge was stabilized, and there were many papers stating that it must on theoretical grounds. The theory used was exactly the same type of programs that “proved” the existence of polywater. Now the interesting thing was that soon everybody admitted there was no polywater, but the theory was “obviously” right in this case. Of course I still had to explain the stabilization of positive charge, and I found a way, namely strain involved mechanical polarization.

So, where did this get me? Largely, nowhere. My supervisor did not want to stick his head above the parapet, so he never published the work on the acids that was my key finding. I published a sequence of papers based on the polarization hypothesis, but in my first one I made an error: I left out what I thought was too obvious to waste the time of the scientific community, and in any case, I badly needed the space to keep within page limits. Being brief is NOT always a virtue.

The big gain was that while both explanations explained why positive charge was stabilized, (and my theory got the energy of stabilization of the gas phase carbenium ion right, at least as measured by another PhD student in America) the two theories differed on adjacent negative charge. The theory involving quantum delocalization required it to be stabilized too, while mine required it to be destabilized. As it happens, negative charge adjacent to a cyclopropane ring is so unstable it is almost impossible to make it, but that may not be convincing. However, there is one UV transition where the excited state has more negative charge adjacent to the cyclopropane ring, and my calculations gave the exact spectral shift, to within 1 nm. The delocalization theory cannot even get the direction of the shift right. That was published.

So, what did I learn from this? First, my supervisor did not have the nerve to go against the flow. (Neither, seemingly, did the supervisor of the student who measured the energy of the carbenium ion, and all I could do was to rely on the published thesis.) My spectral shifts were dismissed by one reviewer as “not important” and they were subsequently ignored. Something that falsifies the standard theory is unimportant? I later met a chemist who rose to the top of the academic tree, and he had started with a paper that falsified the standard theory, but when it too was ignored, he moved on. I asked him about this, and he seemed a little embarrassed as he said it was far better to ignore that and get a reputation doing something more in accord with a standard paradigm.

Much later (I had a living to earn) I had the time to make a review. I found over 60 different types of experiment that falsified the standard theory that was now in textbooks. That could not get published. There are few review journals that deal with chemistry, and one rejected the proposal on the grounds the matter was settled. (No interest in finding out why that might be wrong.) For another, it exceeded their page limit. For another, not enough diagrams and too many equations. For others, they did not publish logic analyses. So there is what I have discovered about modern science: in practice it may not live up to its ideals.