His ’n’ hers Christmas presents:
Giving someone a book on infrared astronomy on the very day the James Webb Space Telescope was launched is either prescient, or premature.
His ’n’ hers Christmas presents:
Giving someone a book on infrared astronomy on the very day the James Webb Space Telescope was launched is either prescient, or premature.
We put the tree up today. It is now beginning to feel a bit like Christmas.
The white sheet hanging up over the books behind the tree is to protect them from the electrical work being done for the conservatory. It has been there for a while ...
We have been having a bit of a problem with mice in the loft. We have trapped and removed several, but how do they get in? A look around the base of the house may have revealed at least one entrance.
A small mouse-sized hole nibbled in an air brick cover |
So now all the air bricks around the house have been protected with a metal mesh cover.
Let’s see you nibble through that! |
The brick edges of the patio area have been built. We want this piece of the patio to be level with the interior of the conservatory, to make it easier to move the smaller telescope in and out. (The larger telescope will be in its own observatory dome, to be built once the conservatory is finished, which should have been several months ago...)
The final small triangular piece at the top of the end wall has been installed, and all the joints caulked and sealed. It's now dry inside.
...that Acorn Computers launched the BBC micro.
Ten years ago, I blogged about this anniversary, and about Moore’s law. (Wow, I’ve been blogging for over ten years!)
Now we’ve had 40 years, or nearly 27 doubling times since the Beeb. So Moore’s law, if it still held, would now be saying today's PCs are 100 million times the power of the Beeb (as opposed to the mere one million times of 10 years ago). Are they?
Thankfully I’ve got only mild side effects from my booster jab: some soreness and redness around the injection site. Oh, and a very visible, but not painful, mark at the flu injection site.
My other half, unfortunately, has the chills, tiredness, and “feeling unwell”, in addition to the sore arm. Still better than the alternative, though.
I had the Pfizer jab this time, in my left arm, and the flu jab in my right arm. I was delighted to learn I was getting a “young person’s flu jab” – because I'm under 65. I don’t know if this means it was a different jab, or just recorded differently; I suspect the latter.
The Pfizer leaflet had some interesting information about side effects. Apparently very common side effects of the Pfizer jab (may affect more than 1 in 10) include headache, joint pain, and diarrhoea, common side effects (may affect up to 1 in 10) include nausea and vomiting, whereas uncommon side effects (may affect up to 1 in 100) include “feeling unwell”. I am pleased to discover that if I get headache, joint pain, diarrhoea, nausea or vomiting, at least I won’t “feel unwell”.
It has been nearly two months since the conservatory frame was erected. Today, finally, the glass was installed!
The latest batch:
UCNC (Unconventional Computation and Natural Computation) 2021 is a hybrid event. About half of us are attending in person in Espoo (by Helsinki), Finland, the rest zooming in for the presentations. This is my fist in person conference for two years. So nice to be able to chat about research to colleagues F2F again!
We are socially distancing in the large lecture hall, except during the photo! |
And now, after a flight, and a trip from Helsinki airport to the hotel in Espoo (next to Helsinki), here's a much nicer view from a hotel window.
In fact, the view is so nice, it calls out for a walk before dinner.
I arrived at Heathrow this evening, ready for my flight to Helsinki tomorrow. Not only will tomorrow's flight be my first one for two years, today's rail journey was my first trip on any form of public transport since March 2020. (Some) normality has been restored, although the mask and the proof of vaccination document is new.
Airport hotels do not have good views:
The work on the pond has been completed: we now have a smaller pond that should be easier to keep full, plus a new bed with an even smaller pond in it!. The remaining bare areas are part of the conservatory work. We also have to refill the pond, plant up the new beds, and reintroduction of water lilies into the pond, to do ourselves.
Sunday working! Very nearly done: all the path edging is complete, some backfilling with subsoil around the perimeter, and the red gravel (to match the house brickwork) has started to be laid. They are coming again on Tuesday to finish off. At which point maybe the other guys can put the glass in the conservatory?
Here's our latest paper, our perspective on mechanical computing. It's not all gears and wheels and steampunk: there are lots of interesting new materials that can be used to build these devices in the small.
Hiromi Yasuda, Philip R. Buskohl, Andrew Gillman, Todd D. Murphey, Susan Stepney, Richard A. Vaia, Jordan R. Raney. Mechanical computing. Nature, 598:39–48, 2021.
Abstract: Mechanical mechanisms have been used to process information for millennia, with famous examples ranging from the Antikythera mechanism of the Ancient Greeks to the analytical machines of Charles Babbage. More recently, electronic forms of computation and information processing have overtaken these mechanical forms, owing to better potential for miniaturization and integration. However, several unconventional computing approaches have recently been introduced, which blend ideas of information processing, materials science and robotics. This has raised the possibility of new mechanical computing systems that augment traditional electronic computing by interacting with and adapting to their environment. Here we discuss the use of mechanical mechanisms, and associated nonlinearities, as a means of processing information, with a view towards a framework in which adaptable materials and structures act as a distributed information processing network, even enabling information processing to be viewed as a material property, alongside traditional material properties such as strength and stiffness. We focus on approaches to abstract digital logic in mechanical systems, discuss how these systems differ from traditional electronic computing, and highlight the challenges and opportunities that they present.
The more substantial edging around the pond is now in place.
However, today was the scheduled end date! We have been promised some weekend working to finish the path edging, lay the top dressing of gravel, and tidy up.
The spaceship has flown away from its base in the pond, to allow the new liner to be laid. First water achieved.
It hasn't flown very far, however. Just to the new bit of patio.
Before it can be replaced, the mounting bracket will have to be bolted back onto the concrete base through the liner, and then everything sealed watertight.
There is more edging around the paths, and more shutterings (ready for pathbuilding) around the pond.
The circular are bottom left is not a rockery (despite currently being a storage site for the rocks removed from the previous pond edge). It is the space being left for a concrete base for the yet to be implemented telescope dome for the telescope we bought in February last year.
Most of the garden work has been on preparing the ground and starting to lay the new patio. New as in a new place, but we are using the slabs from the previous patio, with their lovely patina of lichens.
The frame for the conservatory is installed! No glass yet, though. The installers claim they are waiting for the pond people to finish, so that there is no chance of damaging the glass. But I happen to know they haven't even got the glass delivered yet.
So, as this slowly progresses, we have moved from having an expensive unusable patio, to an expensive unusable pergola...
Meanwhile, the pond work continues, with the path hard core laid out in the right places.
The pond work continues, with shuttering around the back edge for building the path, and blue lines on the ground marking out where the rest of the paths go. The blue lines are in the wrong place.
We had carefully planned to have the new conservatory finished well before we started having work done on the pond. Oh well.
The large pond in garden was initially successful, but we’ve been having trouble keeping it full since we had some shading trees removed. Hot summers lead to rapid evaporation. (Not that this summer has been hot, of course.) Also, the conservatory has led to reduced planting areas.
So the idea is to slim the pond down, surround it with a path, and change half of it into a sunken garden (with a much smaller second pond in its centre, to be nicely recursive).
Today that work started, with a tiny wee digger grubbing out the old pond, leaving a quagmire.
Today saw the first movement on the conservatory build since the end of July. (The glazing has been delayed, several times.) The downpipe had originally been rerouted with temporary fxings, to allow the end wall to be built, although bizarrely the bricklayer just bricked round it.
It has now been properly rerouted, leaving a small hole (visible halfway down the wall), hopefully to be filled in later...
Glazing is promised for next week. Maybe.
I've blogged about variants of Total Eclipse of the Heart before, from Total Eclipse of the Flowchart, and of the Lego, of the lockdown, and even of a slash/Spirk video.
I like the original song, but the original video is definitely ... weird. Recently, there was a BoingBoing piece suggesting that the song is actually about vampires (making it even more SFnal-resonant!) And one of the comments points to a description of that video, set to a rather familiar tune. Enjoy:
There's a new book on Reservoir Computng out from Springer, and it has lots of interesting chapters, including one from us:
Matthew Dale, Julian F. Miller, Susan Stepney, Martin Trefzer.
Reservoir Computing in Material Substrates.
in Kohei Nakajima, Ingo Fischer, eds, Reservoir Computing: Theory, Physical Implementations and Applications, pp.141–166. Springer, 2021.
doi:10.1007/978-981-13-1687-6_7
Abstract: We overview Reservoir Computing (RC) with physical systems from an Unconventional Computing (UC) perspective. We discuss challenges present in both fields, including encoding and representation, or how to manipulate and read information; ways to search large and complex configuration spaces of physical systems; and what makes a “good” computing substrate.
Reservoir Computingis an interesting area of unconventional computing, because it supports computing directly with a wide variety of different physical materials, so it is finding many novel applications.
Our new paper published today, open access:
Simon Hickinbotham, Susan Stepney, Paulien Hogeweg.
Nothing in evolution makes sense except in the light of parasitism: evolution of complex replication strategies.
Royal Society Open Science, 8(8):210441, 2021.
Abstract: Parasitism emerges readily in models and laboratory experiments of RNA world and would lead to extinction unless prevented by compartmentalization or spatial patterning. Modelling replication as an active computational process opens up many degrees of freedom that are exploited to meet environmental challenges, and to modify the evolutionary process itself. Here, we use automata chemistry models and spatial RNA-world models to study the emergence of parasitism and the complexity that evolves in response. The system is initialized with a hand-designed replicator that copies other replicators with a small chance of point mutation. Almost immediately, short parasites arise; these are copied more quickly, and so have an evolutionary advantage. The replicators also become shorter, and so are replicated faster; they evolve a mechanism to slow down replication, which reduces the difference of replication rate of replicators and parasites. They also evolve explicit mechanisms to discriminate copies of self from parasites; these mechanisms become increasingly complex. New parasite species continually arise from mutated replicators, rather than from evolving parasite lineages. Evolution itself evolves, e.g. by effectively increasing point mutation rates, and by generating novel emergent mutational operators. Thus, parasitism drives the evolution of complex replicators and complex ecosystems.
Parasites drive complexity. But how? Here, we examine the outcomes of some computer experiments using our Stringmol automata chemistry (where ‘molecules’ are short assembly language programs, that bind and execute to copy each other), where we can see parasites evolve, then see the measures that evolve that replicators use to guard against parasites, then the counter-measures that parasites use to get round these, then the counter-counter-measures, and so on.
evolution of complex execution strategies (see paper for details) |
Interestingly, we don’t see separate lineages of replicators and parasites co-evolving, but rather each new strain of parasite evolves from a replicator, so that it can exploit that replicator’s defence code itself.
The original bioRxiv version of the paper got a mention in preLights.
I’ve had my current phone, a Samsung Galazy S7, for a bit over 4 years, two on full contract, two on SIM only. I have been thinking for a while about replacing it, because its light sensor has been getting dodgy (clogged with pocket lint, I think, as it improves if I use an air blower on it), and the wifi keeps dropping out.
Anyway, today it bricked. It said something like “UI app stopped”, and nothing would restart it. So, off to Carphone Warehouse, to get a new phone. (This was my first foray into a big shop for over a year!) A very helpful sales assistant and I chatted about phones through our masks. He quickly ascertained I didn’t want anything fancy, or Apple, or large, but did want a reasonable camera. This left the Pixel 4a as about the only option.
That made decision making easy, and it's absolutely fine. It’s pretty basic (which I wanted). It does waste some screen real estate with a Google search bar that can’t be removed. It’s about the same size as my previous phone, but much lighter (I keep checking my pocket, thinking I’ve forgotten it), with more memory, more data, and a relatively cheap monthly contract. I wonder how long this one will last?
My data and apps transfered across really smoothly. But I will have to get a bunch of new charging cables, as I move from proprietary Samsung ones to standard USB-C.
Oh, and it has a sensible alarm clock, where you can make the alarm get slowly louder (functionality annoyingly removed from my previous phone). It doesn’t have the gentle Angel’s Feather sound, but Rolling Fog is a suitable replacement. So tomorrow morning I should be woken gently, at least.
The end wall is now finished, except for a small wedge at the top to accommodate the sloping roof, which will be added once the glass is ready. We hear the glass has been delayed ...
The end wall continues to rise. A temporary gap is left to accommodate the temporary downpipe. Rain stopped play for about ten minutes around midday when the heavens opened, leaving a wheelbarrow full of freshly mixed mortar swimming in water.
The end wall, double skin with cavity insulation, has started to be built. We are having the facing bricks on the inside too, which matches the design in our hall. The other two walls, and roof, will be glass.
The beam and block floor is finished, and the brickwork edging is done. The facing bricks are the same as used for the main house, built 22 years ago. We were lucky the same bricks are still being made, even if they now cost three times as much.
After nearly four weeks of inactivity, due to delivery days, the beam and block floor for the new conservatory was finally delivered and (mostly) installed today.
Danny Yee’s always-interesting Pathologically Polymathic blog pointed me to a great app by Michael Bach for exploring Syke’s Oblique Grating optical illusion.
Set up a grid:
Add some checkmarks:
The alchemist Reed has had twins Roger and Dodger constructed, so that they can manifest The Doctrine and make him all powerful. They need to be raised apart, one with Maths, one with Words, so they do not manifest too early. But they are stronger than he realises, and connect with each other before he is ready. Reed believes he can control them, but if not, he can always destroy them and start again. But he has forgotten the most important rule of Alchemy. Never create a being more powerful than yourself.
This is a marvellous book. In the acknowledgements, McGuire says that she has had the book in mind for a long time, but waited until now because she didn't have the skill to write it earlier. She certainly has the skill to write it now.
Set in modern day America, yet with a lyrical, fantastical feel, constructed children who are nevertheless very real, weird happenings that slowly begin to make sense, contradictory foreshadowings that heighten the tension, real tragedy and heartbreak, and a stunning finale that is a perfect resolution, yet leaves you wanting more: this is a masterpiece.
We like to have turkey at Christmas: it’s traditional. But turkeys are big, and there are only two of us. A medium turkey (for some reason, there no longer seem to be small ones) typically is advertised to serve 10–14 (or in our case, serve two, 5–7 times). Although we did eat several turkey meals durng the festive season, the excess was frozen.
Today, we ate the last of the 2020 turkey. Christmas is officially over!
And we probably got closer to 30 regular servings out of it, without stinting.
It covers approaches to searching, and when to stop looking for improvements over what you already have. It discuses sorting, and tradeoffs between time spent keeping things in order, and time spent finding them later. It covers scheduling, and how the best order to do things in depends very much on what you are trying to optimise. It finishes with game theory, explaining why some situations lead to poor outcomes for all, and how understanding this can help you know how to change the situation to get better outcomes. And it does all this, and more, with a light touch that makes it very readable.
One the one hand, this is great, with an exploration of multiple historical vignettes as the team bounce through time trying to stop Flynn, and as the reason for Flynn’s actions is gradually revealed. Also, the racism and sexism in the past are highlighted: Rufus notes that there is nowhere in history where it was a good time to be a black man; Lucy doesn’t fare that well sexism-wise either, but does manage to get away with several snappy comebacks. (There is an implicit assumption that racism and sexism are no longer a problem in the present, but where else did Lucy get those comebacks?)
On the other hand, it is totally bonkers, with the results of changes in the past having essentially only single effects on the future. For example, the first episode has the conflicting efforts of Flynn and the team meaning that the Hindenburg passengers didn’t die. The only visible effect once they get home is that Lucy’s beloved sister Amy disappears from the timeline and her mother is no longer dying of lung cancer; Amy’s father (who turns out not to be Lucy’s father, to her great surprise, and of subsequent plot importance) married a descendent of a Hindenburg survivor in the changed timeline. So Lucy’s mother never married, and never started smoking. But she still lives in the same house, with the same furnishings, as before… In fact, there’s a bit of a running joke of finding out what change to history resulted from their actions each time, like an extra James Bond film, or a different person being the recognised hero of the event. Also, Lucy, apparently involved because of her encyclopaedic knowledge of history, should become steadily more useless as the past moves away from her knowledge of it.
So, don’t think too carefully about the logic of the timelines. Instead, sit back and enjoy the interesting views of historical events.