The Fermi Paradox: Where are the Aliens?

This question, as much as anything, illustrates why people have trouble thinking through problems when they cannot put their own self-importance to one side. Let us look at this problem not from our point of view.

The Fermi paradox is a statement that since there are so many stars, most of which probably have planets, and a reasonable number of them have life, more than half of those are likely to have been around longer than us and so should be more technically advanced, but we have seen no clue as to their presence. Why not? That question begs the obvious counter: why should we? First, while the number of planets is huge, most of them are in other galaxies, and of those in the Milky Way, stars are very well-separated. The nearest, Alpha Centauri, is a three star system: two rather close stars (A G-type star like our sun and a K1 star) and a more distant red dwarf, and these are 4.37 light years away. The two have distances that vary between 35.6 AU to 11.2 AU, i.e. on closest approach they come a little further apart than Saturn and the sun.  That close approach means that planets corresponding to our giants could not exist in stable orbits, and astronomers are fairly confident there are no giants closer to the star. Proxima Centauri has one planet in the habitable zone, but for those familiar with my ebook “Planetary Formation and Biogenesis” will know that in my opinion, the prospect for life originating there, or around most Red Dwarfs, is extremely low. So, could there be Earth-like planets around the two larger stars? Maybe, but our technology cannot find them. As it happens, if there were aliens there, they could not detect Earth with technology at our level either.  Since most stars are immensely further away, rocky planets are difficult to discover. We have found exoplanets, but they are generally giants, planets around M stars, or planets that inadvertently have their orbital planes aligned so we can see eclipses.

This is relevant, because if we are seeking a signal from another civilization, as Seti seeks, then either the signal is deliberate or accidental. An example of accidental is the electromagnetic radiation we send into space through radio and TV signals. According to tvtechnology.com “An average large transmitter transmits about 8kW per multiplex.” That will give “acceptable signal strength” over, say, 50 km. The signal strength attenuates according to the square of the distance, so while the signals will get to Alpha Centauri, they will be extremely weak, and because of bandwidth issues, broadcasts from well separated transmitters will interfere with each other. Weak signals can be amplified, but aliens at Alpha Centauri would get extremely faint noise that might be assignable to technology. 

Suppose you want to send a deliberate signal? Now, you want to boost the power, and the easiest way to get over the inverse square attenuation is to focus the signal. Now, however, you need to know exactly where the intended recipient will be. You might do this for one of your space ships, in which case you would send a slightly broader signal on a very high power level at an agreed frequency but as a short burst. To accidentally detect this, because you have a huge range of frequencies to monitor, you have to accidentally be on that frequency at the time of the burst. There is some chance of Seti detecting such a signal if the space ship was heading to Earth, but then why listen for such a signal, as opposed to waiting for the ship.

The next possible deliberate signal would be aimed at us. To do that, they would need to know we had potential, but let us suppose they did. Suppose it takes something like 4.5 billion years to get technological life, and at that nice round number, they peppered Earth with signals. Oops! We are still in the Cretaceous. Such a move would require a huge power output so as to flood whatever we were using, a guess as to what frequencies we would find of interest, and big costs. Why would they do that, when it may take hundreds or thousands of years for a response? It makes little sense for any “person” to go to all that trouble and know they could never know whether it worked or not. We take the cheap option of listening with telescopes, but if everyone is listening, nobody is sending.

How do they choose a planet? My “Planetary Formation and Biogenesis” concludes you need a rocky planet with major felsic deposits, which is most probable around the G type star (but still much less than 50% of them). So you would need some composition data, and in principle you can get that from spectroscopy (but with much better technology than we have). What could you possibly see? Oxygen is obvious, except it gives poor signals. In the infrared spectra, you might detect ozone, and that would be definitive. You often see statements that methane should be detectable. Yes, but Titan has methane and no life. Very low levels of carbon dioxide is a strong indication, as it suggests large amounts of water to fix it, and plate tectonics to renew it. Obviously, signals from chlorophyll would be proof, but they are not exactly strong. So if they are at anything but the very closest stars they would not know whether we are here, so why waste that expense. The Government accountants would never fund such a project with such a low probability of getting a return on investment. Finally, suppose you decided a planet might have technology, why would you send a signal? As Hawking remarked, an alien species might decide this would be a good planet to eradicate all life and transform it suitable for the aliens to settle. You say that is unlikely, but with all those planets, it only needs one such race. So simple game theory suggests “Don’t do it!” If we assume they are more intelligent than us, they won’t transmit because there is no benefit for those transmitting.

Ebook Discount

From June 25 – July 2, my thriller, The Manganese Dilemma, will be discounted to 99c/99p on Amazon. 

The Russians did it; everyone is convinced of that. But just exactly what did they do? Charles Burrowes, a master hacker, is thrown into a ‘black op’ with the curvaceous Svetlana for company to validate new super stealth technology she has brought to the West. Some believe there is nothing there since their surveillance technology cannot show any evidence of it, but then it is “super stealth” so just maybe . . . Also, Svetlana’s father was shot dead as they made their escape. Can Burrowes provide what the CIA needs before Russian counterintelligence or a local criminal conspiracy blow the whole operation out of the water? The lives of many CIA agents in Russia will depend on how successful he is.

Energy from the Sea. A Difficult Environmental Choice.

If you have many problems and you are forced to do something, it makes sense to choose any option that solves more than one problem. So now, thanks to a certain virus, changes to our economic system will be forced on us, so why not do something about carbon emissions at the same time? The enthusiast will tell us science offers us a number of options, so let’s get on with it. The enthusiast trots out what supports his view, but what about what he does not say? Look at the following.

An assessment from the US Energy Information Administration states the world will use 21,000 TWh of electricity in 2020. According to the International Energy Agency, the waves in the world’s oceans store about 80,000 TWh. Of course much of that is, well, out at sea, but they estimate about 4,000 TWh could be harvested. While that is less than 20% of what is needed, it is still a huge amount. They are a little coy on how this could be done, though. Wave power depends on wave height (the amplitude of the wave) and how fast the waves are moving (the phase velocity). One point is that waves usually move to the coast, and there are many parts of the world where there are usually waves of reasonable amplitude so an energy source is there.

Ocean currents also have power, and the oceans are really one giant heat engine. One estimate claimed that 0.1% of the power of the Gulf Stream running along the East Coast of the US would be equivalent to 150 nuclear power stations. Yes, but the obvious problem is the cross-sectional area of the Gulf Stream. Enormous amounts of energy may be present, but the water is moving fairly slowly, so a huge area has to be trapped to get that energy. 

It is simpler to extract energy from tides, if you can find appropriate places. If a partial dam can be put across a narrow river mouth that has broad low-lying ground behind it, quite significant flows can be generated for most of the day. Further, unlike solar and wind power, tides are very predictable. Tides vary in amplitude, with a record apparently going to the Bay of Fundy in Canada: 15 meters in height.

So why don’t we use these forms of energy? Waves and tides are guaranteed renewable and we do not have to do anything to generate them. A surprising fraction of the population lives close to the sea, so transmission costs for them would be straightforward. Similarly, tidal power works well even at low water speeds because compared with wind, water is much denser, and the equipment lasts longer. La Rance, in France, has been operational since 1966. They also do not take up valuable agricultural land. On the other hand, they disturb sea life. A number of fish appear to use the Earth’s magnetic field to navigate and nobody knows if EMF emissions have an effect on marine life. Turbine blades most certainly will. They also tend to be needed near cities, which means they disturb fishing boats and commercial ships.

There are basically two problems. One is engineering. The sea is not a very forgiving place, and when storms come, the water has serious power. The history of wave power is littered with washed up structures, smashed to pieces in storms. Apparently an underwater turbine was put in the Bay of Fundy, but it lasted less than a month. There is a second technical problem: how to make electricity? The usual way would be to move wire through a magnetic field, which is the usual form of a generator/dynamo. The issue here is salt water must be kept completely out, which is less than easy. Since waves go up and down, an alternative is to have some sort of float that mechanically transmits the energy to a generator on shore. That can be made to work on a small scale, but it is less desirable on a larger scale.The second problem is financial. Since history is littered with failed attempts, investors get wary, and perhaps rightly so. There may be huge energies present, but they are dispersed over huge areas, which means power densities are low, and the economics usually become unattractive. Further, while the environmentalists plead for something like this, inevitably it will be, “Somewhere else, please. Not in my line of sight.” So, my guess is this is not a practical solution now or anytime in the reasonable future other than for small specialized efforts.

The Virus, and How Science Works, or Doesn’t

It may come as no particular surprise to hear that COVID-19 has become a source of fake news, conspiracy theories, whatever. Bill Gates was one victim. In various assertions, he created the virus, patented it, and was going to develop a vaccine and in it he would monitor people using quantum-dot spy software. Various forms got more likes, shares or comments on Facebook than most news items. Leaving aside the stupidity on view, what about facts? Nobody seems to have asked if he patented it, what is the patent number? Mike Pompeo alleged without a shred of evidence the virus originated in a Chinese laboratory. Political gain and nationalism sure beats truth as an objective there. According to Nature (581, 371-4) an academic subdiscipline has sprung up, tracking the false information, and studying how it is spread. The interesting thing about this is the observation that social-media are run to maximise user engagement and evidence-based information is way back in priorities. 

Also missing was an answer to the question, how does science work? If you watch certain TV shows, someone carries out some weird mathematics on a blackboard, and hey, we have it. It isn’t like that. Apart from a few academics that like to generate papers to keep up their publications, and for people applying standard theory (for example, NASA sending a rocket to a site on Mars, and then it is not a trivial task for a genius on a blackboard) the usual problem is for a new problem where the answer is not known, we sift through the evidence, try to find relationships, use such a relationship to form a hypothesis, then design some method to test it on new situations.

COVID-19 became a problem because genuine information was scarce, in turn because nobody knew, but look what happened as shreds came to light. President Trump advocated an “unproven cure”. But who says? The general feeling seems to be to trust the experts with “good credentials” (the logic falacy ad verecundiam). Since about 1970 there have been hardly any debates, and the funding models of science have forced only too many to “get in behind”. As an example of where wheels fell off, think chloroquine and its hydroxy derivative. 

First, two quotes from Gao et al., Bioscience Trends, 14: 72-3. “results from more than 100 patients have demonstrated that chloroquine phosphate is superior to the control treatment in inhibiting the exacerbation of pneumonia, improving lung imaging findings, promoting a virus- negative conversion, and shortening the disease course according to the news briefing. Severe adverse reactions to chloroquine phosphate were not noted.” and “The drug is recommended for inclusion in the next version of the Guidelines for the Prevention, Diagnosis, and Treatment of Pneumonia Caused by COVID-19 issued by the National Health Commission of the People’s Republic of China.” The Chinese issued a handbook that indicates how and when to use it. 

Then, from Gautret et al. DOI : 10.1016/j.ijantimicag.2020.105949 Twenty cases were treated with hydroxychloroquine. Those who refused, and the cases at another centre were used as a control. Those treated “showed a significant reduction of the viral carriage at D6-post inclusion compared to controls, and much lower average carrying duration than reported of untreated patients in the literature. Azithromycin added to hydroxychloroquine was significantly more efficient for virus elimination.”  Yes, a small sample, and patients who were known to have an allergic reaction to the drug, or other strong contraindications were excluded from the study. There was a third French report of about 80 patients that showed similar good results. Those two papers cited are fairly clear. It does not mean that an iron-clad conclusion should be drawn, but it does suggest potential effectiveness. 

However, a paper was published in The Lancet, one of the most respected medical journals that used statistical analysis from data from 96,032 patients, some of whom were treated with these drugs, and concluded the drugs were not helpful and more likely to cause death. So that should settle it, right? When I read this, my initial reaction was, not so fast. Of those treated, approximately 15% had coronary heart disease, 6% other heart problems, about 14% diabetes, 30% hypertension, 31% hyperlipidaemia, 10% smoked, 17% formerly smoked. Thus 96% had something wrong with them before treatment and 27% smoked or had smoked. Of course, some would not have such problems; some would qualify in two or three categories. The control group had 81,144 patients, and overall, 11.1% died in hospital, with 9.3% in the control group. So treatment made things worse. Convinced?

Do you see a problem? First, the control group may well have had a large number of young people who had mild symptoms, which lowers the death rate, which, as an aside, is remarkably high. New Zealand had a death rate of 1.46%. Second, we have no data on how treatment was selected and carried out. But, you say, statistics do not lie. Actually, that is not true, at least if care is not taken. My first reaction was to think, Simpson’s paradox (https://en.wikipedia.org/wiki/Simpson%27s_paradox), which shows it is possible to get the opposite conclusion if there are confounding variables, and this is particularly troublesome in medical reports where such variables are all over the place. I had had discussions with friends previously where I expressed optimism for the hydroxychloroquine, based on the two papers cited above, then I expressed the “not so fast” view about The Lancet paper. Needless to say, friends thought I was simply refusing to accept the truth.

However, there have been further developments. The Editors of The Lancet published a brief comment stating that “Important scientific questions have been raised about data reported in the paper…” Shortly after a bombshell: (https://www.theguardian.com/world/202…) The data appeared to come from a small US company called Surgisphere, “whose handful of employees appear to include a science fiction writer and an adult-content model”. They refuse to explain their data or methodology. The Australian data came from hospitals that say they have never heard of Surgisphere, and worse, the casualties from the trials exceeded the total Australian casualties. It seems a case can be made that Surgisphere generated fake news, and it was published in two of the most respected medical journals (the other was New England Journal of Medicine).

Following these papers based on Surgisphere results, the WHO attempted to end the use of chloroquine and hydroxychloroquine for COVID-19, and a number of hospitals have complied and stopped using it. 

However, to add to the confusion the University of Oxford published this: “A total of 1542 patients were randomised to hydroxychloroquine and compared with 3132 patients randomised to usual care alone. There was no significant difference in the primary endpoint of 28-day mortality (25.7% hydroxychloroquine vs. 23.5% usual care” (http://www.ox.ac.uk/news/2020-06-05-no-clinical-benefit-use-hydroxychloroquine-hospitalised-patients-covid-19). Now the University of Oxford should be a reliable source, and it clearly shows no benefit in this set of patients but my question still is, how was this set selected? The trial will be randomized, but the overall death rate of 23.5% in “usual care” seems to signal this is a selected set. (Recall the NZ death rate of 1.46%; our doctors are good, but I would not expect them to be that superior to the University of Oxford, so is something else going on?)

So what is going on? I have no idea. My guess is that the chloroquine and hydroxy-derivative do convey benefit to some patients, but not all, and/or they convey benefit but only if some other variable is present. In this context, there is one proposal that chloroquine plus zinc has an effect (https://www.webmd.com/lung/news/20200… ) (although on checking this link before posting shows it has a problem. Who knows what is real?). That apparently came partly from Turkey, and Turkey claims to have been successful with HCQ (https://www.cbsnews.com/news/hydroxychloroquine-coronavirus-covid-19-treatment-turkey/)  If so, the effectiveness in other trials might depend on the diet. Why would zinc have any chance? The chloroquine structure has three nitrogen atoms more or less focused in one direction. Zinc has an affinity for nitrogen, and tries to form octahedral ligands. What that means is, if the chloroquine or derivative can take zinc up to the virus, it has a strong affinity for more amine functions, and could well bind to a nucleobase. If so, the RNA could not reproduce. This produces a hypothesis that has a causal basis and may comply with the data, but only if we had a zinc analysis for all nutrients taken by the patients. Further, it will not work once the virus takes a certain hold because it would be unsafe to put enough zinc into the patient to have a chance.

This example shows in part how difficult science can be, not helped by the likes of The Lancet item. The short answer, in my opinion, is we cannot be sure what works, and hydroxychloroquine probably is at best a means of reducing the virus load and letting the body recover if it can, but then is that not desirable? It would also be helpful if people would stop poresenting false of grossly incomplete information. Maybe one of these days we shall know what works and what doesn’t, but probably not very quickly.

Materials that Remember their Original Design

Recall in the movie Terminator 2 there was this robot that could turn into a liquid then return to its original shape and act as if it were solid metal. Well, according to Pu Zhang at Binghampton University in the US, something like that has been made, although not quite like the evil robot. What he has made is a solid that acts like a metal that, with sufficient force, can be crushed or variously deformed, then brought back to its original shape spontaneously by warming.

The metal part is a collection of small pieces of Field’s alloy, an alloy of bismuth, indium and tin. This has the rather unusual property of melting at 62 degrees Centigrade, which is the temperature reached by fairly warm water. The pieces have to be made with flat faces of the desired shape so that they effectively lock themselves together and it is this locking that at least partially gives the body its strength. The alloy pieces are then coated with a silicone shell using a process called conformal coating, a technique used to coat circuit boards to protect them from the environment and the whole is put together with 3D printing. How the system works (assuming it does) is that when force is applied that would crush or variously deform the fabricated object, as the metal pieces get deformed, the silicone coating gets stretched. The silicone is an elastomer, so as it gets stretched, just like a rubber band, it stores energy. Now, if the object is warmed the metal melts and can flow. At this point, like a rubber band let go, the silicone restores everything to the original shape, the when it cools the metal crystallizes and we are back where we started.

According to Physics World Zhang and his colleagues made several demonstration structures such as a honeycomb, a spider’s web-like structure and a hand, these were all crushed, and when warmed they sprang back to life in their original form. At first sight this might seem to be designed to put panel beaters out of business. You have a minor prang but do not worry: just get out the hair drier and all will be well. That, of course, is unlikely. As you may have noticed, one of the components is indium. There is not a lot of indium around and for its currently very restricted uses it costs about $US800/kg, which would make for a rather expensive bumper. Large-scale usage would make the cost astronomical. The cost of manufacturing would also always limit its use to rather specialist objects, irrespective of availabiity.One of the uses advocated by Zhang is in space missions. While weight has to be limited on space missions, volume is also a problem, especially for objects with awkward shapes, such as antennae or awkward shaped superstructures. The idea is they could be crushed down to a flat compact load for easy storage, then reassembled. The car bumper might be out of bounds because of cost and limited indium supply, but the cushioning effect arising from its ability to absorb a considerable amount of energy might be useful in space missions. Engineers usually use aluminium or steel for cushioning parts, but they are single use. A spacecraft with such landing cushions can be used once, but landing cushions made of this material could be restored simply by heating them. Zhang seems to favour the use in space engineering. He says he is contemplating building a liquid robot, but there is one thing, apart from behaviour, that such a robot could not do that the terminator robot did, and that is, if the robot has bits knocked off and the bits melt, they cannot reassemble into a whole. Leaving aside the fact there is no force to rejoin the bits, the individual bits will merely reassemble into whatever parts they were and cannot rejoin with the other bits. Think of it as held together by millions of rubber bands. Breaking into bits breaks a fraction of the rubber bands, which leaves no force to restore the original shape at the break.