2020 and all that

Since the year is almost over, I thought I would have a small review of the year, from my point of view. From my perspective, the year started with nice warm weather, and rather remarkable sunsets. Australia had some terrible bushfires. Still, all was well where I live. NZ had some fires as well, although nothing like the Australian ones.

My daughter-in-law is Chinese, and her parents live near the edge of Hunan province, but her father travels to work in a factory in adjacent Hubei province, and in February that got locked down. I am not quite sure what happened exactly, but her father could not return home for nearly a week. That is putting in overtime! When Tian announced that Wuhan would build a thousand-bed hospital in ten days, I did not believe her, but they did, in the middle of a lockdown. The Chinese lockdown was interesting. Soldiers from the PLA would but paper tape over everyone’s doors. If you wanted groceries a soldier would take away the tape, you would go collect them, then the tape would be replaced. Break the tape and be naughty, an automatic six months in a Chinese jail, and you don’t get time off for good behaviour. Good behaviour is required, and avoids the consequences of bad behaviour. If your naughtiness could reasonably, in the eye of the party, have led to someone else getting the virus as a consequence of your behaviour, five years. The Chinese behaved and by all accounts the virus was essentially eliminated and life returned to normal in China in a couple of months, other than the odd outbreak from Chinese returning from somewhere else.

Inevitably, the virus landed in New Zealand, and our government tried a strategy of elimination. It was fascinating in that on day one I was out on the road running alongside the bank that encloses my property to cut back vegetation and make it easier for road users. A pedestrian came down the road and immediately crossed to the other side when he saw me. I live on the side of a hill, and I can look down on the main highway going into Wellington. It was weird: almost no vehicles. How could this be? During the major lockdown, my daughter brought me groceries once a week; she, being a senior physician at Wellington Hospital had a priority time for grocery shopping when all and sundry were not allowed. On a personal level, I had one scary moment when the lockdown was eased off. On the first evening, I went to a scheduled meeting that we all thought would be cancelled, but wasn’t. I was driving down what is normally one of the busiest roads in the valley when a van flew out of a commercial building and shot across the road, presumably being used to empty roads. Fortunately, I still have very good reflexes, and it seems good brakes.

The good news is that while there were the odd example of a leakage, the virus appears to be eliminated here, and sports events, summer festivals, etc are apparently going to proceed as usual. While the tourist/hospitality sector has been in trouble, and probably will continue to be, life in New Zealand has returned to normal.

At a personal level, I was invited to write a chapter on hydrothermal processing of biomass by a major book publishing company. I agreed, and that was settled prior to the virus outbreak. I sent in the chapter, but never heard any more about it. I suppose it gave me something to do over the period. I also finished and started revising my next novel, provisionally called “Spoliation” so please go to https://www.inkshares.com/books/spoliation to read chapter one.

The election here had the government returned with a record majority, while in the US there was a narrow defeat. What does this all mean? The most critical problems for 2021 will be how to fix the economies and how to deal with the virus. There are vaccines for the virus, but unless the virus is eliminated, it will stay with us, and now it depends on how long the vaccines work. My guess is revaccination will probably need to be frequent unless we do eliminate it, and I can’t see that happening as only too many countries do not see that as an objective. Meanwhile, the virus is mutating. As for the economies, what happens will be critically dependent on what governments and central banks do. We may be cursed with more interesting times.This will be my last post for 2020. Since it is summer here, and Christmas is imminent, I shall be distracted, but I shall return in mid January. In the meantime, I wish you all a very merry Christmas, and a healthy virus-free 2021.

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Ebook Discounts

From December 18 until the end of the year, my ebooks at Smashwords will be discounted. The fictional ebooks include”

Puppeteer:  A technothriller where governance is breaking down due to government debt, and where a terrorist attack threatens to kill tens to hundreds of millions of people and destroy billions of dollars worth of infrastructure.

http://www.smashwords.com/books/view/69696

‘Bot War:  A technothriller set about 8 years later, a more concerted series of terrorist attacks made by stolen drones lead to partial governance breaking down.

Smashwords    https://www.smashwords.com/books/view/677836

Troubles. Dystopian, set about 10 years later still, the world is emerging from anarchy, and there is a scramble to control the assets. Some are just plain greedy, some think corporate efficiency should rule, some think the individual should have the right to thrive, some think democracy should prevail as long as they can rig it, while the gun is the final arbiter.

https://www.smashwords.com/books/view/174203

Also discounted is Biofuels, non-fiction, which summarizes to what extent biofuels could be a solution to the carbon-neutrality problem, and not from making alcohol from corn. From my own personal research. Summarises what is and what is not a good idea. Be knowledgeable: https://www.smashwords.com/books/view/454344

Exoplanets: Do They Have Life?

One question that NASA seeks to answer is, is there life somewhere else? That raises the question, how can you tell? The simplest answer is, find something that only life can make. The problem with that is that life uses chemistry, and chemistry occurs anyway, so it is sometimes possible that what you find might be due to life, or it might be due to geophysical or geochemical action. Another problem is, some of the molecules that life makes more readily than simple geology does, say, may be difficult to find. When looking for minor traces, it is possible to find “signals” but misinterpret them. In an earlier post, I suggested the so-called signals for phosphine on Venus fell into that class, and what I have seen since reinforces that view. Many now think it was one of the signals from sulphur dioxide, which is known to be there.

One of the strongest indications we could find would be to find a number of homochiral chemicals. Thus when sugars are made chemically, say by condensing formaldehyde, they are either in the D or L configuration. Chirality can be thought of as “handedness”; your left hand is different from your right hand, and the same thing happens for chemicals used by life – life only makes one sort, the reason being that reproduction from nucleic acids only work if they can make a double helix, and that only works if there is a constant pitch, which in turn requires the linking group, the ribose, to be in one form – left or right handed. Amino acids are similar because enzymes only work in specific configurations, as do many of the other properties of proteins. The problem with chirality as evidence of life is that it is hard to measure. The usual method is to isolate the compound in a pure form in solution, pass polarised light through it, and measure the rotation of the polarization. But that really needs a chemist on the spot. Remote sensing is not really suitable. Forget that for exoplanets.

One approach has been to find a gas in the atmosphere typical of life. If you found an atmosphere with as much oxygen as Earth’s, it would almost certainly have life because oxygen cannot be accreted directly by a planet in the habitable zone. The bulk of Earth’s oxygen has probably come from photosynthesis, or the photolysis of water. The latter occurs in the absence of life, but when it does in the atmosphere, it forms ozone, which stops the reaction because water will be below the ozone. On Mars, some water has been photolysed on the surface, but  it formed peroxides or superoxides with iron oxide, or perchlorates with chlorides. So a lot of oxygen is indicative. Another gas is methane. Methane is given of by anaerobic bacteria, but it is also made geologically by reacting carbon compounds, such as the dioxide, with water and ferrous ions, which are common in the olivine-type minerals, which in turn are very common. Almost any basalt will react, in time. So methane is ambiguous.

Perhaps, we should look for more complicated molecules. There are still traps.  Recent work has shown that the chemicals that are part of the Krebs cycle, which is rather fundamental to life, actually can be made from carbon dioxide, iron, and some metal ions such as zinc. Even these are not characteristic of life, although the work may give further clues as to how life got underway, and why the chemicals used in the Krebs cycle “got involved”.

When NASA sent its Viking rovers to Mars, their approach was to treat soil samples with water and nutrients that microbes could metabolise, and then they looked to see if there were any products. One experiment detected radio-labelled gases from samples treated with carbon-14-labelled nutrients, and the idea was if the 14C got into the gas phase, where its radioactivity could be detected, it would mean life. Maybe not. If the nutrients landed on a superoxide, they would have been converted to gas. It is not easy doing this remotely.The one difference that characterises Earth when seen from space is its colour. However, the blue merely means oceans. It is possible that planets with oceans will also have what is required for life, but we could not guarantee that. If we recognised spectral signals from chlorophyll, that would be a strong indication, but whether such signals can be observed, even if there are plants there, is unclear. Again, this is not easy.

Do You Feel Lucky, Punk?

One line from a Clint Eastwood movie, but somehow appropriate as the world faces a sequence of crises, so much so that Physics World thought of it and I have followed suit and report some of the more distressing thoughts as the season for jollity approaches. When I was young, the biggest threat to civilization was considered to be nuclear war. We have avoided that, and it seemed as if that was under control, yet the most powerful country in the world has pulled out of treaties and appears to be developing new weapons. Not encouraging.

The biggest problem this year, the SARS-CoV-2 virus, looks like it is being dealt with as vaccines are now coming available. That was a record production of a vaccine, which shows we can respond to crises in a most rapid fashion. Or does it? Actually, these vaccines did not start from scratch. There have been previous potential outbreaks of dangerous coronaviruses that did not spread, and the pharmaceutical companies had been doing vaccine research for coronaviruses for some time. Yes, this was a new virus, so some new work was required, but the general methodology was established, and the companies would have had good expectations of what would work safely. The companies were prepared. The question now is, how well prepared are we for other disasters?

The most spectacular crisis, from a visual point of view, might be an equivalent to the Carrington event. This occurred in 1859, and corresponded to the sun throwing something like 100 million tonne of hydrogen plasma at us. This was spectacular visually; the northern lights were seen as far south as Colombia. Unfortunately, fast moving charged particles cause huge magnetic pulses that in turn induce serious current in electrical conductors. Back then, telegraph lines took on a life of their own. Now, think of all the conductors in our electrical distribution systems? Electric grids would be in real trouble as transformers burn out. Satellites would have their circuits fried, although the rubbish factor may be eased since the atmosphere would swell up and hopefully bring them down. So, how well prepared are we for this? How many spare transformers, etc, are there where we could get the electric systems going again? If the electric supplies ceased, what would be the effect? In short, we don’t know, we are unprepared, and one day we shall find out, but what are the politicians doing about it? How many politicians even care about what is not immediately in front of them?

We have made some preparation for a potential asteroid collision, in that we are studying and cataloguing asteroid trajectories. For any extinction events we shall have plenty of warning, and time to avoid the collision. Further, our space technology has been developed to the extent that avoiding this collision is plausible.

Politicians are now making noises about climate change, and are putting in place some things that will slow the production of greenhouse gases, but to what extent? Have they done the numbers? I have posted previously that the switch to electric vehicles may not be the long-term saviour some think when you integrate the gases over enough time, and include the gases emitted in making the vehicles, the batteries and the electricity. Nevertheless, it could be a step in the right direction if we worked out how to recycle and rebuild the batteries, and were prepared to pay the price of doing so. The problem is, recycling the batteries per vehicle will produce materials worth a few hundred dollars and probably cost thousands to do it. The obvious way around this is to put the appropriate cost of recovery on the batteries when sold, but that would make the electric vehicle so expensive nobody would buy them. As it is, how many realize they will have to replace the batteries in, say, eight years? How much research is being done into replacements? Take biofuels. Most research has been done by companies, and they have opted for the easiest research, and not that which is most likely to produce the largest supply of fuel. By focusing on ethanol from corn, which even blind Fred can see is not a good idea, it fouls the concept for authorities. How much research has been done into geoengineering? Not a lot. How much preparation has been made to ameliorate the effects of increased temperatures? Again, not a lot. The politicians make many speeches about how things will be OK by 2050, but seem remarkably unwilling to do the hard work now.

Unravelling Stellar Fusion

Trying to unravel many things in modern science is painstaking, as will be seen from the following example, which makes looking for a needle in a haystack relatively easy. Here, the requirement for careful work and analysis can be seen, although less obvious is the need for assumptions during the calculations, and these are not always obviously correct. The example involves how our sun works. The problem is, how do we form the neutrons needed for fusion in the star’s interior? 

In the main process, the immense pressures force two protons form the incredibly unstable 2He (a helium isotope). Besides giving off a lot of heat there are two options: a proton can absorb an electron and give off a neutrino (to conserve leptons) or a proton can give off a positron and a neutrino. The positron would react with an electron to give two gamma ray photons, which would be absorbed by the star and converted to energy. Either way, energy is conserved and we get the same result, except the neutrinos may have different energies. 

The dihydrogen starts to operate at about 4 million degrees C. Gravitational collapse of a star starts to reach this sort of temperature if the star has a mass at least 80 times that of Jupiter. These are the smaller of the red dwarfs. If it has a mass of approximately 16 – 20 times that of Jupiter, it can react deuterium with protons, and this supplies the heat to brown dwarfs. In this case, the deuterium had to come from the Big Bang, and hence is somewhat limited in supply, but again it only reacts in the centre where the pressure is high enough, so the system will continue for a very long time, even if not very strongly.

If the temperatures reach about 17 million degrees C, another reaction is possible, which is called the CNO cycle. What this does is start with 12C (standard carbon, which has to come from accretion dust). It then adds a proton to make 13N, which loses a positron and a neutrino to make 13C. Then come a sequence of proton additions to make 14N (most stable nitrogen), then 15O, which loses a positron and a neutrino to make 15N, and when this is struck by a proton, it spits out 4He and returns to 12C. We have gone around in a circle, BUT converted four hydrogen nuclei to 4helium, and produced 25 MeV of energy. So there are two ways of burning hydrogen, so can the sun do both? Is it hot enough at the centre? How do we tell?

Obviously we cannot see the centre of the star, but we know for the heat generated it will be close to the second cycle. However, we can, in principle, tell by observing the neutrinos. Neutrinos from the 2He positron route can have any energy but not more than a little over 0.4 MeV. The electron capture neutrinos are up to approximately 1.1 MeV, while the neutrinos from 15O are from anywhere up to about 0.3 MeV more energetic, and those from 13N are anywhere up to 0.3 MeV less energetic than electron capture. Since these should be of the same intensity, the energy difference allows a count. The sun puts out a flux where the last three are about the same intensity, while the 2He neutrino intensity is at least 100 times higher. (The use of “at least” and similar terms is because such determinations are very error prone, and you will see in the literature some relatively different values.) So all we have to do is detect the neutrinos. That is easier said than done if they can pass through a star unimpeded. The way it is done is if a neutrino accidentally hits certain substances capable of scintillation it may give off a momentary flash of light.

The first problem then is, anything hitting those substances with enough energy will do it. Cosmic rays or nuclear decay are particularly annoying. So in Italy they built a neutrino detector under1400 meters of rock (to block cosmic rays). The detector is a sphere containing 300 t of suitable liquid and the flashes are detected by photomultiplier tubes. While there is a huge flux of neutrinos from the star, very few actually collide. The signals from spurious sources had to be eliminated, and a “neutrino spectrum” was collected for the standard process. Spurious sources included radioactivity from the rocks and liquid. These are rare, but so are the CNO neutrinos. Apparently only a few counts per day were recorded. However, the Italians ran the experiment for 1000 hours, and claimed to show that the sun does use this CNO cycle, which contributes about 1% of the energy. For bigger stars, this CNO cycle becomes more important. This is quite an incredible effort, right at the very edge of detection capability. Just think of the patience required, and the care needed to be sure spurious signals were not counted.