Clovis and after…

North America was devastated by a cometary explosion as recently as 12,900 years ago, according to a bunch of geoscientists at a recent meeting. Now a palaeoanthropologist has chipped in…

Comet theory collides with Clovis research

…pointing to the apparent decline in a Clovis-style culture, known as the Redstone culture, just after the putative comet explosion. Clovis and Redstone are known, as cultural groups, by distinctive spear-points and the later Redstone points are much, much rarer than the Clovis points – about 5-to-1 in numbers. Very odd, unless the originating people group has declined.

Plasma life

New research on plasma crystals raises the prospect of inorganic helices encoding genetic information…

‘It might be life Jim…’, physicists discover inorganic dust with life-like qualities

…for a long time I have pondered the possibility that UFOs – unexplained ones, not the mundane sort – are caused by coherent plasma structures that we can call “alive” though not ‘organic’. Work on plasma crystals seemed a way for plasma beings to have some sort of stability though made out of a medium in continual flux like plasma, and now this new work has confirmed my suspicions.

If plasma beings – which I call “plasmons” even though that means something else in optical physics – exist how would they manifest to us? Balls of glowing light are one possibility – their raw physical natures concentrated and leaking visible energy. They might also, after co-existing with us for millennia, know how to manipulate our perceptions magnetically, via fine-scale magnetic-field variations around our skulls to excite our neurones. Plasmons might then appear in whatever form the brain dredges up to explain the imperfect firings of neurones – could religious, paranormal & UFO visions result from plasmons trying to communicate with us? Being plasma they could have existed almost from the dawn of time, spanning the cosmos, perhaps even playing a role in the creation of life on “cold matter” worlds like our own.

Think on it.

Palaeoanthropology chaos

Old bones speak volumes, but how we understand them depends on our prejudices. The latest news about Homo erectus and Homo habilis is that they aren’t a simple ancestor-descendent set of species. Instead they co-existed…

Fossils Could Force a Rethink

Twin fossil find adds twist to human evolution

…though that’s an arguable point. Tim White, of Berkeley, points out that the putative habiline jaw is distorted and hard to get precise measurements off – an important thing as erectus and habilis are very similar in that particular feature. Even if the jaw is just an Erect, the new skull is really interesting – all the robust features of the Erects, but very small.

Small enough, perhaps, to produce a Hobbit after a bit of island dwarfism?

Another interesting bit of news is the idea that bipedalism was a feature of our last common ancestor (LCA) with the Asian and African apes. Both orangutans and gibbons walk around on tree-branches using two legs and a new study has supported the idea that our LCA with the orangs was a biped…

Red Ape Walking

…a curious bit of the article is some palaeoanthropologists pointing out the knuckle-walking peculiarities of Australopithecus afarensis which, they say means we humans evolved from knuckle-walkers. Perhaps not, I say, as very recent molecular work suggests a split between humans and chimps at c. 4.1 mya, not long before the appearance of afarensis with its chimp-like features. Perhaps A. afarensis is a chimp ancestor? After all chimps and gorillas have had as long to evolve their peculiarities as we have had to evolve ours. Much of what we see in them today is, potentially, as derived from our LCA as what we see in ourselves.

How Big is a Planet?

Stars are fundamentally different to planets and one surprising way in which they differ is just how big they can get. Heavy stars get hotter and they puff-up from very fast fusion rates – stars heavier than the Sun fuse hydrogen chiefly via the much faster carbon-nitrogen-oxygen cycle, which is a minor cycle in the present Sun. What faster fusion rates means is that the big, fat stars are BIG – some are much larger than the Sun. Some are so large and violently bright that they’re losing mass into space, forming gigantic nebula. One spectacular example is Eta Carina and its rather pretty nebula.

But what about planets? “Cold” matter – anything less than a 10,000 K – supports itself against the remorseless pressure of gravity by electrostatic forces, rather than the fusion heat of a star’s interior (which is over 3,000,000 K at a minimum.) As the pressure increases – and thus the planet’s mass – the electrons and nucleii of the planet’s core part company, becoming pressure ionised. Past this point the planet is supported by the mutual Pauli exclusion of electrons, which has some strange properties, one of which is increasing mass causes the planet’s size to shrink. When this happens the core is said to be composed of degenerate matter. Shrinking a planet releases energy and this causes the interior to become increasingly hot, puffing the planet up slightly. As a result planets heavier than Jupiter are roughly all the same size – roughly Jupiter size (about 10% of the Sun’s diameter.)

But that’s planets composed of so-called “cosmic abundancies” of matter – about 3/4 hydrogen, 1/4 helium and a bit of everything else. Planets can lose all their gaseous hydrogen/helium as they form and thus be composed of things like water, carbon, sulphur, “silicates” (chiefly metal oxides) and iron. Other elements are too rare to make bulk components of a planet, though they can be selectively concentrated in the outer crust (like uranium/thorium and potassium seem to be on Earth.) A new paper has come out discussing just how big a planet made of such things can get, with some interesting results…

Mass-Radius Relationships for Solid Exoplanets

…one of the co-authors is Marc Kuchner, who has previously enticed us with descriptions of carbon-rich planets, and planets made of ice. A few years ago one of the first exoplanets in a circular habitable zone orbit was discovered…

HD 28185

…and it masses about 5.7 Jupiter masses. Most exoplanet watchers assumed it might have habitable moons – if moon mass scales linearly with planet mass it should have about 4-5 moons as big as Mars – but one brave soul thought the planet itself might be a “super-Earth” made of Earth-like stuff. At that mass, if silicate/iron mixes didn’t get denser with pressure, the planet would be as big as Jupiter (about 12 Earth diameters) with about 12 gees gravity. But, as the new paper describes in detail, such materials get a LOT denser with pressure, and the MAXIMUM size a super-Earth can get to is 3 Earth radii. Thus HD 28185b would have a surface gravity of 200 gees – a most unsuitable home for life-as-we-know-it.

Hypothetically, though, what would such a planet be like? Firstly it would have 1800 times the radioactive material heating up only 9 times the surface area – thus a radioactive heat flow of 16 watts (cf. Earth’s mere 0.08 W.) Such a heat-flow would mean the planet would remain at 130 K even without a star – though that’s an average temperature, and in reality much of the surface would be lava. With so much tectonic activity and so much mantle heat flow gases and volatiles wouldn’t remain trapped in its mantle for long – it would probably be wrapped in a thick layer of superheated steam and carbon dioxide, the surface aglow at over 900 K before its heat could escape into space. Even in interstellar space the planet would glow a dull red and remain at hellish temperatures for billions of years.

Bible errancy

As I noted below, the Bible contains history and has a history. During the course of its development certain quite notorious “exaggerations” of specific numbers crept in – famously the +900 year ages of pre-Flood patriarchs, like Methuselah’s 969 years, and the shorter, but still implausible, ages of post-Flood patriarchs. Abraham is said to have lived to 175, Isaac to 180 and Jacob only managed 147. There’s no evidence anyone ever lived so long in all human history, so such figures have to be either deliberately inflated by Biblical scribes or misread from old ancestor-lists. Either option is unacceptable to a believer in “Biblical Inerrancy”, but fits with the principle that God accommodates his message to its listeners and uses their pious scribblings to deliver His Word to those ready to hear.

Less obvious number games give us some exaggerated census figures in the book of “Numbers” – on two separate occasions Moses counts the Israelite men, 20 and over, as 603,550 and 601,730 – implying a much larger populace. By itself such figures aren’t totally absurd, but a moving population of over 2 million would have stood out like a sore thumb in the archaeological record of the Sinai. Tent traces, bones from their flocks, latrines, fireplaces and small personal items tend to last in such dry, dusty conditions, and they exist through archaeological time, but only for an estimated 20,000 or so people at any one time.

Also the Bible itself calls the numbers into question.

Firstly, it claims Israel was to displace 7 much larger nations – and that would’ve crammed the Levant with living traces that just don’t exist. A population of over 14 million just can’t live in that region with Bronze Age technology, and even today the few million in Israel/Palestine is stretching the limit.

Secondly, it gives us a proxy for the number of adult women by its recording of a count of Firstborn males, 1 month old or more, amongst the Israelites – surprisingly low at 22,273. Unless the average number of male children per woman was about 54 plus then clearly someone has messed up the sums.

So what happened? And why did no one notice?

The second is easiest to answer – misplaced piety. A bit of thought caused any rational person to say “there’s something wrong!” but no one wanted to commit “blasphemy”, Jewish or Christian, by questioning what “Moses” wrote. Eventually the Enlightenment brought rationalism to Biblical criticism, but of a rather negative variety that consigned all such Bible stories to the “pious fiction” bin. I want to avoid that trap, myself, so I’d rather believe some scribes got the figures wrong, and misplaced piety meant later scribes let the error stand.

The first question is much harder to reconstruct an answer to because we have no clear idea of what the original figures were. If we accept the 22,273 figure we also have to accept the number of Levites was 22,000 – which might be a bit high. Later in the book the number of male Levites between 30 and 50 is recorded as 8,580, which doesn’t quite fit the 22,000 total either. But if we accept that as an average, then 13 tribes of Israel (12 + Levi) has roughly 286,000 males, and the total populace is roughly double that. Still a bit high in terms of Firstborn… the average woman has had about 26 kids. Since earlier in the Book of Exodus only two mid-wives are mentioned this is a tad high.

Let’s call this one a work in progress. In an associated page I’m going to put down all the genealogical data in the relevant books and that can be the data to work off. Bright ideas welcome!

Chilling Venus

An old SF dream, independently invented by Olaf Stapledon and Jack Williamson, is the idea of terraforming. Venus has long been viewed as a suitable target. When CO2 was first found in huge amounts in the 1920s, Stapledon imagined giant electrolysis stations converting the atmosphere. In the 1940s the “dry formaldehyde” Venus was a popular model and became the setting of Poul Anderson’s “The Big Rain” – the planet-obscuring clouds were believed to be formaldehyde polymer dust and the surface was a dry 100 degrees C. Clever chemistry would convert the clouds into water and eventually the Big Rain would fall.

By 1960 the clouds were believed to be water and the surface was roughly 270 degrees C with about 2 bars pressure – thus Carl Sagan’s famous suggestion: seed the clouds with algae to convert the CO2 into oxygen. But by 1963 Sagan had abandoned the water cloud model and the temperature was estimated to be a scorching 700 K with about 100 bars of nitrogen causing a super-greenhouse effect and “cloudiness” was due to scattering. Larry Niven famously described the surface conditions as “a searing black calm” and proposed Earth only avoided such a fate by the early Moon stripping excess air away.

By 1968 Russian Veneras had shown the surface to be even hotter and the atmosphere to be almost all CO2. The clouds had become a total mystery because the measured water vapour levels were so low. Venus’ surface was depicted as a stormy darkness with red-hot patches of glowing rock. Carl Sagan’s idea of seeding the clouds had become SF mythology and remained unchallenged.

After the probes of 1974/5 – Venera camera landers and Mariner X – the clouds were known to be sulphuric acid and the surface was surprisingly bright. More like an overcast day on Earth than an abyss of Hell, though even hotter at 735 K. By 1976 serious studies for terraforming Mars had also led to a re-examination of Venus and the realisation that it was too dry for algae. To make O2 from CO2 requires H2O – and 90 bars of CO2 needs an ocean of water to turn into algae and oxygen. But all that oxygen was far too much oxygen. James Oberg’s “New Earths” proposed combining the oxygen with hydrogen tanked in from the Outer Planets – Saturn being a favourite. A bit “cart before the horse” because there would be no oxygen made without water…

A number of approaches were proposed through the 1980s, but the scenarios all required millennia. David Brin mentions a 10,000 year terraforming project being undertaken by the Earth Clan, to impress the Galactics that we “wolflings” weren’t too hot-headed and impatient to join Galactic society. Nice fiction, but unlikely for a standard human society to undertake. Paul Birch proposed in 1991 a different approach – why not cool Venus enough to freeze out the atmosphere and then bury it for later export off-world?

That’s the new “orthodoxy” of terraforming – chilling Venus’ atmosphere with a gigantic soletta parked in the Sun-Venus L1 point. A major question, then, is just how long would it take to cool, condense and freeze? Currently Venus’ “photosphere” – the region heat escapes from – is at a temperature of about 231 K, but this is due to the high cloud deck giving the planet a high albedo in visible and IR light. Chilled just a bit and the cloud deck would probably collapse since its main component is sulphuric acid, which boils at over 338 degrees C at 1 atm. With a higher emissivity Venus would lose heat somewhat faster, but just how much heat is there?

Carbon Dioxide (96.5% of the atmosphere), unlike nitrogen (3.5%), has quite a variable specific heat capacity – it stores more heat, the hotter it gets in the temperature range in Venus’ atmosphere. Nitrogen remains pretty stable, being a diatomic molecule, but carbon dioxide is triatomic and thus its ways of storing energy are quite complex. I’ve created a model of this process in an Excel spread-sheet and it has some interesting results, which I’ll elaborate on in a future post. But for now basically the hotter Venus’ photosphere is the quicker it’ll lose heat.

Once the temperature of the lowest layers reaches about 31 C the carbon dioxide will start condensing at the 74 bar pressure level, with interesting results – the phase-change heat liberated will drive convection, perhaps keeping the upper layers at a roughly constant 31 C until all the condensible CO2 below the 74 bar pressure level has rained out. Then it will only continue condensing, as the lower levels cool, down to a partial pressure of about 5 bar. Liquid CO2 can’t exist below that pressure – it’s either ice or gas past that point, and as it cools it will increasingly freeze-out, perhaps coating the underlying seas of cold CO2 in a pressure cap – except, unlike water ice, it’s heavier than its liquid phase. A bit of water might be needed to ice over the cold CO2 seas, which will be percolating into Venus’ regolith, and probably making geysers all over as it cools the underlying rocks. A big fraction might then be trapped in the regolith, but Venus’ sub-surface will probably be too hot for it to remain there indefinitely.

Once the CO2 is frozen out and capped over what remains? The nitrogen won’t freeze or liquefy under such conditions and so will make an atmosphere of about 3 bars, which would be a bit much for a prolonged human presence. The regolith might soak up a bit and some will probably “dissolve” in the CO2. Big thinkers have proposed haulling it off-world for Mars and free-space habitats, providing a long term export product. All the CO2 would be even more valuable as carbon nanotubes might eventually be the macro-engineering material of choice, with a theoretical 2 teraPascal strength. Stephen Baxter has Venus supplying carbon across the Galaxy for the War against the Xeelee in his novel “Exultant.” I would hope for something more peaceful.

My daughter’s first-typing… apryll jane georgia crowl, 5

Human Nature isn’t PC

A cute and informative article from Psychology Today

Ten Politically Incorrect Truths About Human Nature

…which is quite a good popular update of current evolutionary psychology ideas. One thing it brushes over a bit lightly is why men find older women less attractive than younger, yet men seem to age without us noticing. Simple fertility ratios between ages – older women are less likely to have kids who will then survive and be parents. Thus a two-fold process occurs – men who find older women attractive lose out in reproductive competition and women who age visibly are favoured, by reproductive success, over women who don’t age so visibly, thus confusing potential mates.

Yet there are still men and women who “buck the trend” – I always think of Isabella Rossellini when I think of ageless feminine beauty. Natural selection isn’t always a perfect gene-editor and variation within a population always produces differences – some women remain fertile into their 50s, while others might become menopausal in their 30s.

Abiotic Production of Oxygen/Ozone

Planets with carbon dioxide rich atmospheres won’t produce oxygen or ozone is amounts large enough to look misleadingly like an Earth-like planet…

Abiotic formation of O2 and O3 in high-CO2 terrestrial atmospheres

…but only if they have oceans. If the planet is frozen or a desert then the geochemical sinks for O2/3 produced by photolysis of CO2 won’t be working and they can build up. Thus signs of water, mild temperatures and oxygen means an oxygenic biosphere, not funny chemistry.

Except… Venus during its runaway greenhouse phase probably lost an ocean of water and had a very thick oxygen atmosphere as a result – but did that show? Scalding oceans covered in cloud, to an astronomer looking at its very cold cloud-tops (250 K) it probably looked like an “icehouse” and not a nice “Pale Blue Dot”.

Jesus is Lord!

Not a sign of a sudden conversion, but more of a gentle steering back into faith. For the last 8 years I have been an avowed agnostic – with occasional lapses. But recently I have had to admit to myself that I believe more than I doubt, so agnosticism is untenable. But just what do I believe now? I have always had problems with the view that the Bible was inerrant (“100% without error” as one Church web-site claims), but I have also had problems with calling it all irrelevant to faith whether the Bible stories are historically true and accurate.

If the Bible has to be “demythologised” then what remains distinctively Christian? What remains the “message” (kergma in Greek) of the Gospel?

Rudolf Bultmann gave a name to the demythologisation craze of the 20th Century, but really people had been rationalising over the Bible stories way back to Isaac Newton and Baruch Spinoza in the 17th Century. Unlike Newton or Spinoza I personally want to remain Orthodox in my doctrines, but even then that is a pretty broad target.

The first step, I think, is deciding what to make of the Bible. Nowhere within the text itself does it claim the books we call “The Holy Bible” is totally without error. Instead it is said to be “God-breathed” – i.e. the Spirit moved prophets and preachers to write the books that make it up. But all of them came to the task within a particular historical context – the Bible is not just history, but has a history. And that history has to be understood.

Also if the Bible is inspired – as Orthodoxy preaches – then reading it and gaining an understanding relies on the Spirit’s action as well. In fact I would make the claim that all error – heresies and so on – stems from exalting human understanding over the meaning the Spirit wishes to convey to us. That doesn’t mean Dogmatic Theology – writing bulging books of “god-talk” – can’t be done systematically or without use of scholarly techniques, but it should always remain open the moves of the Spirit.

More importantly the Bible isn’t the living Word of God without the Spirit. You can’t read it as God’s Word without listening to the Spirit’s voice. Else it’s just “The Bible” – a fallible product of fallible humans. And, unlike Jesus, the Bible didn’t have a Virgin Birth.

As the Book says “Why do you say I am Good? Only One is Good.”

The New Omega Point Theory II

At the Friendly Atheist blog I made this comment as a summary of Frank Tipler’s new Christian Omega Point Theory…

The “Theory of Everything” he promotes is nothing new – just the Minimally Extended Standard Model, plus a quantum gravity equation developed years ago. And Tipler’s use of the Many Worlds approach to Quantum Mechanics is nothing new either.

Somewhat batty is his ideas about Jesus using macroscopic sphaleron fields to cause super-rapid proton-decay, turning a tiny bit of mass into a neutrino beam to carry him across water, or turning neutrinos into “loaves and fishes” to feed the 4000. Basically he’s saying “miracles” are really “God-tech”, literally, and so only use physical law, rather than violating it. If you believe that God is the Omega Point then I guess those sort of miracles might work.

Most of his claims have pretty solid physics behind them BUT he’s saying his take on the physics is the ONLY valid approach. That’s where his claim to some kind of divine truth really has problems. His strident advocacy of the Many Worlds version of QM, for example, might have problems because of recent experiments that potentially falsify it.

Tipler also thinks the quantum gravity equation of Richard Feynman and Steve Weinberg is correct – but it has been rejected by most physicists working on quantum gravity because it has an infinite number of terms when expanded and can’t be renormalised. Tipler argues, perhaps validly, that many proofs in mathematics potentially involve an infinite number of statements, but I think most physicists working on quantum gravity are hoping for a set of equations their finite minds can handle. Tipler might be right but his case is a LONG way from proven.

As for his Apocalyptic hyperbole… well I’d blame it on his faith tradition’s penchant for “Left Behind” style dramas in human history. Except more than a few Futurists expect radical changes as Super-Intelligence is developed. He’s certainly not a lone lunatic voice on this one – for example Vernor Vinge thinks the Singularity is only 50 years away.

…and I feel I need to expand. My promised critique is waiting on getting a hold of his book, “The Physics of Christianity”, which isn’t looking good – maybe not until August (i.e. overseas order for my Birthday.) Even “Borders” doesn’t have it here in BrisVegas, which is annoying. But I’ve read a lot of his online material and so I think I have some idea of what he’s saying.

“Somewhat batty” isn’t an intentional insult BTW. Atheists tend to see all claims of miracles as absurd, and claiming that Jesus’s miracles are thanks to Omega Point technology (macroscopic sphalerons) is only a bit less weird. As a rule theists haven’t claimed to know the mechanism of God’s interactions with the world in any detail – Tipler is a pioneer, and a brave one in that regard.

Do I believe him?

Firstly, I am unsure if the specific miracles Tipler focuses on need to be explained as real events. Biblical scholarship has cast serious doubt on the nature miracles as anything other than parabolic fictionalising of prophecies about Jesus-as-Messiah. But the problem with that approach is that Jesus, as a real person, fades out of view if we start hacking away at the Gospels in an over-zealous attempt to demythologise. We have to use “discernment” to disentangle history and historicised prophecy in the New Testament, and that’s pretty subjective. In epistemological terms (“how do we know”) Tipler has used as much imagination as the demythologisers who decide what’s history and what’s not.

So if we accept them as events to be explained, then what? Tipler’s ideas become one possibility amongst many – and that’s my main issue with the Whole of his thesis: that physics has already uncovered The Truth. Which physics?