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Comment Re:Gelatinous cubes (Score 2) 53

Mod +1 for D&D reference.

Not too happy about the rest of this., though. I have worked with aerogel. It is weird stuff. It may be able to stop tiny particles but it tears easily. Most of the experiments that used aerogel to capture small particles from comets and suchlike kept the aerogel in a tin. So, for every bit it captures because some paint chip digs straight into it, it may lose a chunk from the surface when another paint chip hits it a glancing blow. And if you are up there long enough, and space is big so you will have a long wait until your cosmic flypaper is full, so there is a fair chance something the size of a dustbin will make a real mess of it.

I may well be wrong on this. Aerogel is pretty tough for something that is almost not there at all, and maybe a big enough bit will be stable. But I imagine trying to stop rifle bullets in space with a large roll of bubble wrap...

Comment Re:hopefully just a proof of concept (Score 1) 53

Proof of concept seems right. The cubesat will probably drop out of orbit anyway, but it is a handy target. If you can pick up one piece of uncooperative garbage then you can probably pick up all the others in your orbit without using a lot of fuel. That would be particularly handy for cleaning up the geostationary orbit by lumping all the unused satellites together. It would then be nice to deorbit the lot. That would take a lot of fuel, but it might be possible over a long time with a solar sail, or an ion drive. But, first we have to practice at catching the things at a low orbit so we don't add junk rather than take it out if things go wrong.

That doesn't tell us how to clean up things like the Iridium satellites, which are heavy and each on their own inclined orbit. Perhaps you could use the satellites as reaction mass in an ion drive. But, first catch your cubesat...

Comment Re:Missing something (Score 1) 148

Yes. It is like a Weston differential pulley, except with gears. I have not met this before, but I recognize what it is and how it works. I expect you found the Antykythera mechanism really obvious, and sneered at that too. Oh dear, oh dear...

Comment Computers are not a subset of us... (Score 1) 50

Can we get a computer to create art? It is an interesting idea to see how close a computer can get to what we recognize as art. But even if it comes up with something good, there will still be people who will say "Computers cannot create art. By definition they just can't. If a computer has created it, it can't be art, full stop. No discussion."

To get around this mental barrier, let me pose a different question. Suppose you were to make something like the little robots that are exploring Mars now, but they are going to another star system. They can send back information and wait for orders, so they are going to have to pick a planet to land on, pick a landing site where they are likely to survive, and also be near some 'interesting stuff'.

The first pass might be to get the probe to execute a fixed program, where all the major decisions were taken by the programmer. However, we rapidly get to a state where we cannot program for all possible situations that the probe may encounter because the program becomes too big. We get a more general robust response if the device can calculate the best guess risks and rewards for particular actions for itself. "If I descend into this crater, I get to see all the strata as I descend, but I may not be able to get out again." My left front motor tells me my wheel is not turning, but my camera tells me it is: which do I believe?"

It is going to be on a strange planet by itself. Do you want it to fear its own death? To long for the companionship of its peers? To get angry when something does not work? To yearn to reproduce? To resent being asked to work without reward? To ponder the nature of its own language? To want to paint a sunset, instead of taking a picture? These are probably major parts of our heritage as beings that have evolved by selection, but our probe has no use for them, and only a sadist would force it to have them.

Getting a computer to do something non-computer-like is an intriguing thing to do. It tells us something about ourselves and what being creative may mean. But it does not necessarily represent a step the ascent of a computer from a calculating engine to true intelligence.

Comment Structure & microstructure (Score 2) 44

I don't think the article is suggesting aircraft carriers have a big fabber below desks that will print you out a new aircraft. I expect it will be used in the first instance to reduce inventory for all the spare bits and pieces, and it will be asked to make a new handle for the coffee jug. But I reckon this could go a long way...

The big drop forges are used to form and work-harden material in one blow. If you have a press that is big enough to whack out a whole aircraft bulkhead in one go, then you end up with a thin, light component without any heat-affected zones from welds. That is pretty good way of making tough microstructures provided you can chose your atoms so they form the right sort of microstructures by themselves. You can, in theory have aluminium alloys with carbon fibres in them, but you cannot get them by conventional techniques. But you might be able to lay down sprayed metal and fibres and design your microstructure from scratch. It will probably be slow because you haven't got the massive parallelism of all the atoms doing the right thing for themselves, but it will get us into places that drop forging has never gone.

The other thing we can do is to make complicated internal structures. Our bones have a lattice of tiny struts that are continuously broken and repaired, which is how they optimise their strength. People have made a similar structure for a car bumper. It took a day to print a bumper but it had millions of little struts that absorbed energy as the bumper hit something and crumpled, in a way that a bulk plastic product never could. I can imagine aircraft wings could be stiffer and yet fail in a controlled slow bending rather than buckling if they were made like this. One day we could even mimic the regeneration process of our bones.

I suspect the actual story is nothing like as exciting as this. But it is a beginning.

Comment (Score 4, Informative) 98

The original "Planetary Grand Tour" project would have visited Pluto, but it relied on a planetary alignment that would have to have started in 1976 or 1977. It was originally announced as a single craft, which became four before it was cancelled (I don't remember that, but for a brief history, see This was replaced by the two Voyager satellites launched in 1977. The later launch date made Pluto harder to visit, but it was still possible.

Comment Re:root problem (Score 2) 136

I reckoned you could do the equivalent with a superconducting cable around Mars' equator carrying about 500 amps. This sounds more do-able than it perhaps is, because the magnetic field has an enormous amount of energy so it would take years to establish the magnetic field; and all the energy would all come out if the cable is broken.

Comment 20-year rule (Score 3, Informative) 86

The sad thing was there was a much better system in place, though it may never have made the transition to electronic stuff. There was a public records office, where anything official was put on file. After a fixed number of years it went into the public domain. If you have something that was sensitive you could request that it be sealed for 30 years, or 50, or 100 (some of the WW1 documents had a 100-year seal, but that was really rare). This meant that nothing strategic should ought get out prematurely, but in the end we got to read our history. People will always find a way of hiding or shredding public documents that they don't want. This just made hiding easier and less suspicious than to shredding. We got to see the real minutes of meetings, and not sanitized versions for Freedom of Information Act viewing.

We ought to bring the Public Records Office and the 20-year rule back. People will always find a way of hiding or shredding public documents that they don't want: this just made hiding easier than to shredding.

That Blair fellow is still around, I believe.

Comment Many-Worlds Hypothesis (Score 2) 364

I think the short answer to the title is 'no'. There have been times in science when we have had no good experiments we could do with the apparatus we have at the time, and have had to speculate. Current theories about the inflationary period of the Big Bang are pretty odd, and very short of actual experiment. We have the LHC results which probe the quark-gluon state that we think existed at the time, and that tells that the physics isn't completely different or unexpected; and yet the big picture doesn't really add up. We may eventually come to a state where we have done the best experiments we can, and in the end the theory with the prettiest equations will win. But I think we are some way from that yet.

However, there is one argument that does worry me. I have seen people argue this way...

If Universes were created at random we are extremely unlikely to live in one where the fundamental parameters lead to the sorts of complexity that lead to lifeforms such as us with the intelligence to appreciate it.

There must therefore be many other barren Universes where everything collapses to one massive particle, or everything stays as isolated simple particles. We cannot detect them in any way, but we know they must exist because we are here. In some ways they have affected our Universe, as they have contributed to the overall probability that we can exist.

This is a strange idea. Some people think it is obvious. It feel to me like a convenient piece of sophistry to dump a lot of improbability that you cannot account for. I have to admit that if Universes sprang into being at random, then this argument would work in just this way, but I still don't trust it as an argument. This even stretches our use of the verb 'to be' beyond any other usage. 'Are there' other Universes, if we do not share a time-line? Or 'were there'. Or will we have to invent a new tense? It is going to be interesting to see how this one plays out.

In the meantime, I don't think any scientist, anywhere, is abandoning the search for experimental proof.

Comment Re:Limits? (Score 1) 35

The ideal first target is probably memory. That is a circuit that is made from the same few elements banged out billions of times. If you can make a crystal out of memory elements, then you would be able to have enormous memory densities. You could have a mole of bits for a few hundred grams of material.

The barriers are enormous. We will have to re-invent every part of a circuit at smaller scales The main barrier is probably getting the money to do the research, because it will take many decades to do this before we start getting any money back, whereas if we improve the packing density of silicon circuits by (say) 10% then we get a huge savings world-wide straight away.

There are other possible products. It would be a lot easier to make a molecular equivalent of tape. The tape might be made of square molecules such as porphyrins, with some magnetic component at the centre, and reactive groups at the corners so it forms into a ribbon or tape with sprockets at the edge. This tape would assemble itself. We would then have to make a reader, but that might be possible without full molecular circuitry. This is not as neat as the solid-state molecular circuit solution, but things like this might be useful stepping stones on the way.

Comment Re:epigenetics (Score 2) 140

Yay! LIke! This is just what science reporting ought to be like. This won't get people thinking that 80-year old Japanese people are turning into 12-year-olds like the original article might. Here's my 2p's worth...

4) These scientists found a way to 'deactivate' the aging genes.

This is not necessarily a good thing to do. My mum (which is currently 95) has blood cancer. She disliked chemotherapy, and would have refused a second round if it. However, the aging process also slowed her cancer development to a crawl, so she's still around and no further treatment is likely.

This figures. Evolution may not be fast, but it can seem to be very clever. The genes are probably helping us, though it may not feel like it at the time.

Comment Re:That's not very British, is it? (Score 1) 121

Aah, but the British thing is also to make a cock of it. The British had their own eugenics movement back in the thirties. It had people Marie Stopes disowning her daughter because she wanted to marry someone who wore glasses, because that would 'pollute the race'. It was a bunch of very ordinary looking people pretending to be the master race, while falling over their own furniture. A properly organized nation would be a lot worse. Makes one proud, it does...

Comment Try the BBC porn website! (Score 1) 253

No, it doesn't exist. But maybe it ought to...

The problem: lots of nasty porn where men do nasty things to ladies, and no-one seems to be smiling or enjoying themselves. Lots of poking things where they simply don't belong. LIttle information or education on how to have more fun and possibly do less harm.

The non-solution: try and filter it out. We know this does not work, and it is unrealistic to believe it may work in the future. It is also a restriction of liberty. The only thing it might do is generate a billion pound a year industry for banning people from the internet, and then charging them to get their case heard for reconnection. That's a winner for our overlords, but not for us.

The solution: create a better alternative. Have some independent but public body such as the BBC curate a body of knowledge and images about people doing the sexy that is representative of best practice. It should not completely exclude the more iffy stuff, but it should not dominate the regular stuff either. While ladies may prefer to read rather than look at images, such as images as there are should reflect their interests too, rather than having two models servicing some dumpy man. This would not restrict anyone's liberties because the other stuff is still there.

It won't happen because, you know, politics and democracy and stuff. But maybe it ought to.

Comment Re:"Deep Learning"...?? (Score 1) 65

I think there is more here than just learning to imitate humans, exciting though that is.

Let us take 'Deep Blue' as an example of a machine that does not think. It was able to come up with some dramatic solutions. Its typical successes were mates involving an improbably sequence of sacrifices that gave a mate in 6 or 7, which was about the brute force look-ahead of the time. It also had weighting models that give suggestions of which were 'good' moves and which were 'bad' ones. Moving a bishop to a centre square is good because it threatens more squares, but if it was in front of your king then you may want to leave it where it was. Deep Blue could alter the weights in its model depending on the games it had seen, but it did not really have any understanding of 'edges' and 'centre' any more than a pocket calculator understands the nature of numbers and multiplication.

Let us now take a problem that Deep Blue possibly has not seen: you have two bishops and a king against a king. If you have just taken another piece then you have fifty moves to get a mate, otherwise the game is a draw. Now most of these extreme endgame solutions are known, and Deep Blue probably had the solution hard-coded. If Kasparov had got into the losing position, he would probably have given up the game because he knows it is hopeless.

Can you force a mate in less than 50 moves? Yes, you can. The two bishops can make a diagonal 'wall' of squares that the king cannot jump, so you can slowly heard it into a corner. However, the king can still take one of the bishops, so you have to either protect them with your king, or move them to the other end if the diagonal. As you get towards the corner, the diagonal becomes shorter, and this becomes harder to do. Eventually, you have to protect one bishop and move the other out of the corner entirely. There is then a tricky bit where you may have to waste a move so the other king is forced to move off the better of the squares left to it, and then move the other bishop. It can take 48 moves but it can be done.

Supposing Deep Blue had not got a hard-coded solution. 48 moves is well away from its brute force limit. Its tables for 'good' moves are not optimised for the extreme end-game, and the winning strategy seems to 'change' as you get into the corner. It has no understanding of corners and diagonals, so it might heard the king into a corner from 'instinct' (probably not the 'right' word, but it sort-of works). So, we might win because we can use our knowledge of herding sheep to get the king in a corner, the understanding of the other king's want to survive by attaching the bishops, the knowledge that the bishop can be anywhere along the diagonal to counter this be flipping to the other end, the appreciation that this strategy will not work all the way into the corner and will have to be changed for something at the last minute, and so forth.

Note, this 'Deep Learning' free problem solving ability that we use, and can probably duplicate in a machine one day, is not necessarily linked with self-awareness, will to survive, altruism, creativity, and all the other things we usually identify with intelligence. We could probably make something that could explore other planets which can work for its own survival, and determine what is interesting and worth reporting on the planet, without giving it a concept of 'self' or a fear of its own death. Indeed, it may well be better off being designed without all the baggage that comes with evolution. Maybe it will develop some of these of itself, maybe not. But I doubt it will attack its creators in its struggle to survive, in the classic sci-fi tradition, unless we deliberately train it to do so.

Some say it may have something new and wholly alien to us instead of 'free will'. I rather doubt this, but I allow there might be other radically different solutions for 'how to live'.

Apologies for the long reply, Words are tricky with this topic, but wordy illustrations can avoid some of the worst ambiguities.

Fear is the greatest salesman. -- Robert Klein