Author: Adam

Long term habitats

Red dwarfs… trillion year real estate

Red dwarf stars are the slow living members of the galactic community. Just why sheds light on some odd denizens of the galaxy. The maximum sustainable temperature in the core of a star is dependent on its mass, and the rate of fusion in that core is dependent on the temperature to about the 7th power – thus a star that’s half the Sun’s core temperature of 15.7 million K is burning protons some 2^7 (128) times slower in a lower mass core. Slowly burning its hydrogen a minimum mass red dwarf (0.08 solar masses) will last for about 13 trillion years before going out, almost literally as if switched off. Unlike heavier stars there’s no red giant stage, just a gradual brightening until its final decline a few billion years before the end of hydrogen fusing. Greg Laughlin, Fred Adams and Peter Bodenheimer modelled the long-term evolution of low mass Main Sequence stars… The End of the Main Sequence …and for stars in the 0.08 – 0.2 solar mass range the picture is much the same, trillions of years of slow brightening and an end that’s a bit brighter, then a ‘quick’ decline. In the 0.2 – 0.25 solar mass range the stars end more like red giants and less like helium-rich dwarf stars. Another feature of low mass stars is they convect almost all their material and thus end up fusing 98% of their hydrogen – unlike our Sun which ends up fusing only about 8% of its hydrogen on the Main Sequence. Why the convection trick, which seems so unfair? A cooler core and a denser star. Consider, a 0.1 solar mass star has a radius of 0.125 of the Sun, which means it’s 51 times denser than the Sun, with a gravity that’s 6.4 times higher too.

Below a few million degrees in the star’s core and the fusion reaction rate is ridiculously slow and essentially doesn’t happen, so the “star” is actually a brown dwarf, which only shines by virtue of gravitational collapse. The heavier the brown dwarf, the more it can collapse too, so lighter brown dwarfs run out of gravitational energy much quicker than heavier ones.

Brown dwarfs are, oddly enough, closely related to white dwarfs – star corpses – which also only shine via gravitational collapse, and then by the slow trickle of their massive internal heat capacity. White dwarf collapse is halted via electron repulsion – the so-called degeneracy pressure caused by electrons being crowded too much and gaining Heisenberg Uncertainty energy. Without that repulsive force the white dwarfs would collapse into black holes after radiating away a few trillion years worth of heat. According to work on Supersymmetry (SUSY) by L. Clavelli a white dwarf can ‘catalyse’ the transition from our broken SUSY world to a world of exact SUSY in which there’s no degeneracy pressure to stop the star from collapsing into a black hole. Such a transition is sudden and would produce a massive release of all its gravitational energy as gamma-rays – highly collimated gamma-rays just like a humungous laser, or gamma-ray burst.

But what if the energy release is slowed down? If the collapsing star radiated at the Sun’s current output – but a much higher temperature because it is so much smaller – then as its mass trickled away as radiation (4.5 million tons a second is a ‘trickle’ to a star) then it would last some 14 trillion years if it massed the same as the Sun. This is about 1,150 times the Sun’s expected life-time as a fusion-powered star, a vast improvement for intelligent life in our system. The question is: how do we control the rate of collapse so our Sun doesn’t become a massive laser? We only have a few billion years to find out.

If Jesus Lived Today

Haldane on JC in modern times

J.B.S.Haldane was a biologist at the forefront of his field in the 1920s & 30s, and like a lot of scientists then, a Marxist. But he wasn’t the usual duckspeak Party Marxist with nothing original to say. Here’s one little essay about JC…

IF JESUS LIVED TODAY

Most of my readers are, at least nominally, Christian. I am not. I can say to them, as Blake did :

* The vision of Christ which thou dost see
* Is my vision’s chiefest enemy.
* Yours is the healer of mankind,
* Mine speaks in parables to the blind.

I see Jesus as a man whose perception of spiritual facts was extraordinarily intense. He was far more intelligent, as appears from his sayings, than his disciples They misinterpreted his words, and as we only see him through their eyes we cannot know how he would appear to our own.

If Jesus were born in our time of a poor Jewish mother in capitalist Europe or North America he would receive a far wider education than 1900 years ago, when his reading was probably confined to the law and the prophets. Perhaps it was for this reason that his general ideas were always stated, either in parables drawn from everyday life, or in the terminology of religion. Today he could talk in terms of science, psychology, an economics. So quite possibly we should not think him primarily as a religious leader at all. In his own time he tried to simplify religion, and was accused of blasphemy. Today most religious people would probably regard him as an infidel.

Most of us would first learn of his existence through the Press. A reporter sent down to investigate a story of unprofessional cure of mental diseases writes a curious account of it, The healer is of an unusual type. So far from being sanctimonious, he is a confirmed beer-drinker. Indeed there is a story about that he miraculously put back all the pub clocks in Whitechapel at closing time. He has a keen sense of humour, and refuses to give a straight answer to religious queries. `Come and live with me,’ he tells the reporter, `if you want to find out about God.’ `I almost took him at his word,’ adds the reporter.

Later the police begin to take notice. This man is always talking about the coming revolution, sometimes in very violent terms. But it is difficult to pin him down. At one moment he says that he is an enemy of peace and has come to stir up disorder at another that the revolution must take place in the mind. And his attitude to the rich is surprising in a revolutionary. He wants to abolish wealth, not because rich men are wicked, but because they are unhappy. `It’s easier for a motor lorry to get through a keyhole than for a rich man to enjoy life,’ he is reported to have said. The Communists hate him even more than the police and the parsons.

After two or three years he becomes an intolerable nuisance to the authorities. His followers have been making disturbances in churches and public places. The movement appears to be growing. Crucifixion is out of date. A trial offers too great an opportunity for publicity. A simple method is available for imprisoning an innocent man for life without trial. It is effectively used today by the Roman Catholic hierarchy in Canada against their opponents. The man has seen visions. A witness says that he stated that he was one with God. Another asserts that he stated that he could rebuild the law courts in three days. Two doctors, already jealous of his unprofessional healing activities, certify him insane. A devoted police agent who has actually managed to become treasurer of the Man’s movement smoothes the way for the arrest. His suicide shortly afterwards merely proves that this maniac has spread insanity around him, or so the Press affirms. Soon afterwards it is announced that the madman has died in an asylum. The plain man breathes a sigh of relief, and turns to the financial column of the Press. He is one of the many who, in the words of the Man, keep their hearts in their safe deposit.

But the affair is not over. Some of the Man’s followers say that he is still with them. Others are beginning to spread his doctrines. They say that he has revolutionised psychology, and made it as practical as chemistry. He has taught the art of happiness. You cannot love yourself unless you love your neighbour first. If you find fault with him it is a sign that you are really angry with yourself. Some of these men and women disciples certainly seem to exhibit a wholeness of personality which is something fresh in the world. It often lands them in prison, but an increasing section of the public is attracted by their ideas, and still more by their manner of life. The revolutionary idea is in the air that the rich are a set of mutts who do not know how to enjoy life. A few rich men and women actually give up their fortunes and claim to be tasting happiness for the first time. But another section of disciples have different ideas. They stress the mystical side of their master’s teaching and his remarkable cures of disease. The authorities encourage them. This will only be another new religion, and the State is not afraid of religions. In spite of occasional aberrations, religion makes for stable government.

The future is unknown. Has the Man started the real world revolution, or only another religion ? The world’s future depends on the answer.

(Published in a 1932 collection of essays entitled The Inequality of Man.)

…found online at Haldane on Life, Death and Jesus.

Alternative-style “proteins”

For several years molecular biologists have been fiddling with the machinery of Life, trying out its capabilities. Now a new kind of “protein” made from beta-amino acids (different to our alpha-aminos by having an extra carbon) have been synthesised and seem able to mimic regular proteins… Chemists show that nature could have used different protein building blocks. All this research, plus work on alternative coding systems in DNA, enable molecular tailoring of bacteria to specific tasks – like making gasoline out of sunlight and carbon dioxide, or making amorphous carbonia out of the world’s excess cee-oh-two.

Systemic

Megabytes of astronomical data are collected every second by automated probes and telescopes around the world, but finding something meaningful and new in that torrent is quite laborious. One effort enlisting the power of distributed intelligence (i.e. you & me, and our computers) a team of astrophysicists are trying to extract traces of new extrasolar planets from radial velocity observations of nearby(ish) stars… this is Systemic. Dowload their Systemic Console and the program lets you tweak the possible orbits of possible planets to inch towards better statistical fits – and in the process you might find even more planets, hidden in the “noise”. Even more importantly you might find a planet which can be detected by its transits across the face of its star – several planets are known by their shadows. In the next few years it’s highly likely that an Earth-sized planet will be “seen” in this negative fashion, probably around a red-dwarf star.

But what has been found already? The most complete reference for extrasolar planets is Jean Schneider’s The Extrasolar Planets Encyclopaedia which is as up-to-date as humanly possible – Jean’s found a few himself, so he’s definitely got his finger on the pulse of discovery. Not counting your own discoveries via Systemic, that is…

Ocean Planets… soon

If Neptune was a bit cooler then it would have a deep ocean full of dissolved hydrogen, instead of what’s probably a super-critical atmosphere of dense “vapour”. According to modelling, by Sloane Wiktorowicz and Andrew Ingersoll, Voyager’s gravity data for Neptune rules out an ocean, which would be denser at a shallower depth than an all vapour atmosphere. Yet there’s a chance that Voyager tracking wasn’t quite as precise as certainty in this matter requires, so Neptune might yet be an Ocean Planet.

Ocean planets are a fairly new idea, based on advanced modelling of the Equations of State of silicates, ice and iron/nickel. Basically the planets are heavy enough to fully differentiate according to the density of their most common elements and compounds – volatiles on top, silicates in-between and dense iron-nickel alloy in the Core. The most common volatile is, of course, water, followed by carbon dioxide (after methane decomposes) which dissolves and precipitates into a layer within the water. Thing with water is that it forms a huge range of ices. We know ice as amorphous ice and crystalline ice, but under sufficient pressure liquid water will form (mostly) Ice VII, which can remain solid up to quite high temperatures (its triple point at 22,000 atmospheres is at 85 degrees C.) While thousands of atmospheres of pressure isn’t achieved anywhere in Earth’s oceans an Ocean Planet is half ocean, which means Ice VII (and higher pressure phases of ice) forms a thick, dense mantle surrounding the inner silicate mantle and the core.

What results is a liquid ocean about 100 km deep, a layer of carbonate, then Ice VII beneath that for thousands of kilometres. The atmosphere can be H/He, but if the planet is small enough it might not capture a lot of primordial gas, and instead it may out-gas the standard chondritic mix recently determined by geochemical analysis – methane, ammonia, nitrogen and hydrogen. Both the methane and ammonia will eventually be oxidised by reacting with oxygen produced by photolysis of the water, making more water, nitrogen and carbon dioxide. On a smaller world an aerosol of longer hydrocarbons would form a haze protecting the ammonia and methane somewhat, but a larger world’s atmosphere would wash it out before it could accumulate.

Would Life find a foothold on such a world? You might think that so much water meant an idyllic environment for life, but in reality oceans are vast deserts with a very thin veneer of life. Most of the action happens in shallow seas and lakes, something lacking on an Ocean Planet. Yet I can’t shake the thought that methanogenic life might not cause a different outcome for carbon on such a world, turning it into eventually a slick of hydrocarbons, instead of deeply buried and dissolved carbonates. But I very much doubt animal life and an oxygen biosphere.

As PhysOrg News has noted Ocean Planets may be detectable very soon.

Wormholes and Singularity

Wormholes are general relativistic short-cuts through space-time, currently unobserved, but made famous (or infamous) by Star Trek, Stargate and Sliders, and little understood. Originally described by Einstein and others – famously the Einstein-Rosen bridge mentioned briefly in SF ever since – but shown to be dynamically unstable to any infalling light or mass. That is until Carl Sagan challenged his friend Kip Thorne to come up with someway of making wormholes stable. Ever since that famous thought-experiment wormholes have been described and designed in a multitude of physics papers – but do they exist?

Nikolai Kardashev and Igor Novikov are instantly recognisable names to space-nerds like myself – inventor of the Kardashev scale of civilisations, and master of black holes respectively. Just recently they’ve collaborated on a paper… Astrophysics of Wormholes …which describes what wormholes, in varying states of traversibility, might look like. And infact they’d look a lot like the Active Galactic Nucleii of many, many galaxies.

Another team of researchers have also suggested a different way to find wormholes – inside Black Holes. A Black Hole is usually described as “sucking in everything” like some sort of irresistable force, but in actual Black Hole physics the picture is more complicated. From a distance a bare Black Hole is just a mass with gravity like any other – but invisible (and thus a candidate for dark matter) -, but within a few radii of the Black Hole (its radii not yours) the situation gets dramatic. Small Black Holes have immense tidal forces and will shred anything into atoms. Within 3 radii and the Black Hole does strange things to space-time – if it’s rotating then space-time gets dragged with it, creating an ergosphere. Nothing can resist turning with the Black Hole within the ergosphere, but dumping mass into it might give you enough energy to escape back out. A similar process allows Hawking Radiation to escape and whittle away the mass of a Black Hole over immense aeons of aeons of time.

But within the Event Horizon there’s no escape, not even for light. Space & time trade places and all motion is towards the Singularity, where the mass of the original object that formed the Black Hole has been crushed to oblivion leaving a distortion in space-time. A rotating Black Hole has a Singularity shaped like a ring – and if you can pass through the ring you’ve passed through a wormhole. One that’s normally inaccessible. However according to recent computations of the effects of an electromagnetic excitation of the Black Hole, found here… Electromagnetic Excitation of Rotating Black Holes and Relativistic Jets …the Event Horizon can be opened up and the wormhole revealed. Perhaps if the wormhole goes somewhere this might actually be useful.

And that’s the puzzle. Relativity gives no clear indication of where wormholes end. They might link to other places (and times) in our Universe or in other Universes. When the worm-ways of the Universe are finally explored there will be a whole new breed of adventurers required to travel to their far-ends, risking being lost in a wholly other Universe and time. After hardy explorers have mapped the wormhole network of the Universe what will happen then?

According to Ray Kurzweil they’ll be the communications web of the The Intelligent Universe, our ultimate descendent, the Universe-filling HyperComputer, which will include us within its matrix. His is a grand cosmic vision in which the super-exponential growth in computation will drive us to turn the Universe into Mind-full Computronium and live in a virtual world that caters to our whims. If we aren’t already there…

Daedalus Time Budget

Event Time (seconds) Mass (tons) Acceleration (m/s2)
Light up 0 54026.2 0.14
First Tank drop 2.1570E+07 38205.9 0.197
Second Tank drop 4.3140E+07 22355.5 0.337
Third Tank depletion 6.4700E+07 6795.2 1.109
Second stage 6.4700E+07 5098.2 0.13
First Tank drop 9.2450E+07 3014.8 0.22
Second Tank drop 1.2030E+08 981.6 0.676
Manoeuvre begins 0.0000E+00 931.5 0.712
Manoeuvre ends 5.5500E+05 656.5 1.01

Takes a bit of explaining, but the table is really in two parts. When the probe is nearing its target it manoeuvres around to place its sub-probes for the best fly-bys of interesting targets in the system, spreading them around far and wide. Each sub-probe has a dust-bug to put out a protective dust-cloud to ionise any meteoroids that might otherwise ram into it – something virtually certain as Daedalus plows through interplanetary space at 12.2 % of lightspeed.

Hello world!

Finally I’m here. But what to post? Been very busy staying at home with the baby who has spots across his torso including his arms. My GP was puzzled enough to call in her senior at the practice to have a look. Possibly what’s called the fourth disease which is a viral rash that is so mild it hardly rates as a disease.

Dogon Shame

Phil Coppen is an esotericist with an unusually sceptical approach to the topic – rightly so, since so much is tendentious rubbish in the esoteric world. He considers the rather poorly handled case of the religious views of the Dogon people in Mali…

Dogon Shame

…in which he reveals the anthropological source of the “data” that indicates the Dogon knew of Sirius’s dark companion (a white dwarf drowned out by Sirius A) was actually the “source” of that knowledge, a certain Martin Griaule, who had studied them as an anthropologist and wrote an article that became Robert Temple’s The Sirius Mystery. When Walter van Beek went and spent a decade with the Dogon in 1991 he discovered that they knew next to nothing of the elaborate lore that Griaule had reported in 1950 and had been Temple’s inspiration in 1965.

Case closed, but there’s one point left unexplained. The Babylonians, and the Hindus, both speak of Seven Sages who assisted the first Kings of Man and actually accompanied them on the Ark. According to Berossus the Sages, specifically Oannes, were amphibious and only half-human – not gods or demons, but something else in the form of man. Carl Sagan and Iosef Shklovskii considered this case, in their Intelligent Life in the Universe, to be the most likely example of contact with ETIs – though far from proven. And the Sages are connected with Sirius – but why? Sirius A & B are far too young to be likely prospects for native ETIs to have evolved – B is believed to have already gone through its red giant stage and mass-dumped onto A. Thus the whole system has already been baked by a star going through the Asymptotic Giant Stage i.e. bad news for life.

Strange Days

Of course there’s some weird stuff going down around the world – look at all the brain/machine interface work that’s happening. And improvements in brain imaging will allow individual neurones to be scanned in real time. Could a brain be scanned in sufficient fidelity to allow a human to upload? Not yet, as even the beefiest super-computer is only just creeping into human brain territory of raw number crunching power. Emulating a brain faithfully might be a few orders of magnitude away, and we still don’t know how much the basic architecture (serial versus massively parallel) affects consciousness yet.

OTOH what does it take for a brain to run Humanity 4.3.4?

Notice the version number – if Ardipithecus is the first unique human ancestor 1.0 (rather than a possible LCA 0.0 like Sahelanthropus or Orrorin), then Australopithecus anamensis is 2.0, and A. afarensis is 2.1. Add other “South Apes” as you see fit. Then we get the Habilines – H. habilis, H. georgicus, and H. floresiensis (the Hobbit) – who are 3.1, 3.2, 3.1.2 respectively. Finally we get humans of modern gross anatomy – H. ergaster (4.0), H. erectus (4.1), H. heidelbergensis (4.2), H. neanderthalensis (4.2.1), and H. sapiens (4.3). And since we sapiens turned up, there have been a few upgrades, with the final version (4.3.4) coming Out of Africa c. 50,000 bp.

Version 3.1.2, the Hobbit, had an advanced, but very compact brain – down to about 400 cc of neural volume. That’s about 1/3 modern levels, which suggests we have a lot of “bloat-ware” filling our skulls. The Hobbits made tools and even had fire, which is quite impressive for such tiny forms. The low body mass probably helped free-up a fair bit of brain for other things, though the relationship is non-linear.

A friend of mine, Glenn Morton, is a geophysicist who has a unique theory on when and how God made humans a distinct lineage to our Last Common Ancestor (LCA) with the chimps. He believes Noah’s Flood was the terminal flooding of the Mediterranean in the Messinian, some 5.5 million years ago. As the only hominids around back then had chimp-sized brains this does make for a difficulty – how could Noah have been smart enough? Now the Hobbit suggests the problem is somewhat more complicated than simplistic comparisons with chimps imply. After all the chimps have spent about 6.5 million years evolving away from our LCA too, so who knows how they compare to our mutual progenitor?

Glenn also thinks that Adam was made from the “clay” of an LCA who had died from genetic incompatibilities. God thus rewired and cleaned up the LCA’s genetics, breathing into this new creature something distinct from other apes. To my mind this implies a lot of fiddling by God, but then our species Creation was supposed to be a miracle, one of the few occasions in Genesis when God actually did something directly.