James Kasting Online

In 1964 there was Stephen Dole’s “Habitable Planets For Man” which was the first informed guesstimate of habitable planets in the Galaxy. Dole’s planets had optically thin atmospheres and no modeling of their climate’s temporal evolution. The HabZone was from about 0.75 AU to 1.25 AU.

In 1978 Michael Hart presented the first evolution models of habitable planet atmospheres and discovered they were incredibly unstable – a very narrow band around the star allowed a long term stable atmosphere – but even Earth’s was due to become uninhabitable within a 100 million years. The HabZone had narrowed to just 0.95-1.01 AU – any further out and Earth became locked in ice; any closer in and the Earth became a greenhouse.

Then in 1993 James Kasting and his posse shook things up by accounting for climate stabilisation via carbonate weathering – and the habitable zone widened to 0.95 AU – 1.4 AU, perhaps even further. The year before Kasting & Ken Caldeira had extended the use-by for Earth’s biosphere to c. 1 billion AD. The odds for life in the Galaxy went up, and the mystery of the Fermi Paradox became an even bigger mystery.

Much to my surprise and joy most of James Kasting’s classic papers are available online…

James Kasting’s papers

…spanning his early 1980s papers to the present. Thank you James!

Notable papers are “The Lifespan of the Biosphere Revisited” (1992) and “Habitable Zones Around Main-Sequence Stars” (1993), but lots of other meaty stuff for planetology nerds like myself.

Random mutation, directed search

Fortune as ‘randomness’ or ‘chance’ – how the sticks fall – is a big part of biology’s insistence on the non-directed nature of mutation. And I don’t take exception with the idea that what we see in mutation isn’t directed at a solution in a trivial sense. Most mutations seemingly ‘just happen’. A lot of Christians are scandalised by the idea of ‘random mutation’ but biology is revealling more to the story than mere base-pair flips due to chemicals or UV photons.

What seems to occur is genomes in a population under stress collectively perform a search for a viable mutation, and as has been increasingly realised in molecular biology genes seem to be organised to mutate and still remain viable. Parts of genes seem to be able to hyper-mutate in response to external stresses affecting the organism, while other sections seem to resist mutation. In microbes this means the mutations will be inherited, but in multi-cellular organisms the separation of germline cells from soma-line cells is hard to cross. But it does seem to happen. Epigenetic modifications to offspring are being increasingly recognised as caused by the environmental experiences of the mother.

Thus mutation isn’t guided to a perfect solution – instead genomes seem optimised to allow enhanced rates of variation as a means of searching for a viable solution to a stressor. The collective behaviour of the population seems to work like a “learning machine” – what gets called a perceptron or neural network in computer science – which computes, as a distributed system, a new genome in response to environmental changes. Thus, as Greg Bear fictionalised in “Darwin’s Radio” and “Darwin’s Children”, there is Mind-like behaviour in evolution. There is also a lot of information transfer via viruses and horizontal gene-transfer, much like what Greg Bear imagined.

That’s what our current understanding seems to be telling us – not so much an external Intelligent Designer, separate to the process, but an immanent ‘Mind’ that searches out new solutions through the success or failure of individual genotypes-expressed-as-phenotypes. And that Mind uses more than just base-pair flips and random movements of blocks of DNA during recombination to get things happening. Gene expression can be modified even without changing the genes, mothers can modify the expression of their children’s genes, and there are plenty of other tricks in the Mind’s toolbox.

Of course for a Christian the question arises as to just how that Mind relates to God. I propose we see the natural Minds immanent in the evolutionary process as God’s agents – perhaps even “angels” – but they may not be self-reflective, and may merely be automatons. Programs if you will. But then we are but programs in the wetware we call our brains. We imagine ourselves to be separate individuals, but our minds share a common information sea we call “society” – much like the “pool of genomes” that a species population represents. If we are such tiny sub-programs in something bigger, and yet still conscious, then maybe They are conscious too. If so, then the case for them being Angels is stronger.

If so then we must ask: is the Angel of genus Homo a Fallen Angel? Is that why Satan is called the god of this Aeon and is able to say “all these kingdoms are mine“? Terribly Kabbalistic speculation and perhaps totally baseless, but the more I think on it, the more the idea gains credence. Howard Bloom’s two classic books on the concept of distributed intelligence in evolutionary processes are titled “The Lucifer Principle” and “The Global Brain”, both of which explore the role of hierarchies and social orders in evolution. One particular idea is that we each have our own “Inner Judge” that determines if we’re socially connecting, successfully or not. Failure to connect leads to “condemnation” and a failure to thrive. Recent work has shown that “loneliness” causes changes in our immune systems – we become more vulnerable to illness. People who accept the Inner Judge’s case basically lay down and die. Or actively suicide. All quite irrationally, but seemingly instinctively.

“Satan” means “Accuser” – the Inner Judge’s Prosecutor – and as Jesus put it “he was a murderer from the beginning.” In that light we don’t need to imagine a Devil as something exterior to us. Instead its power is from the evolutionary machinery that makes us NEED to be a part of a bigger social system. But the individual human ego doesn’t accept the condemnation of the Devil lightly – we can either turn to a different archetype (the Self=Christ, as Jung puts it) or we can embrace the Accuser, and accuse society back. People like Anton LeVey and Marilyn Manson consciously sided with the Satanic symbol and point out quite truthfully the flaws and failings of ostensibly Christian mainstream culture.

A great Christian thinker, Jacques Ellul, once pointed out that because Satan is the Accuser in God’s Court, then we must listen to his case against us and answer it squarely. Anything else, especially evasion, is claiming we’re without sin, and thus coming under the power of the Prince of Lies. Satan can only be defeated by truth, because everything else is from him. Knee-jerk reactions by Christians to challenges to their personal cultural idols… it only hurts themselves.

Deep Future for Mankind?

Doctor Who in its last three episodes for the 2007 season presents us with the ultimate fate of humanity. The Universe is collapsing into giant black holes and the last human survivors of the year 100 trillion (or so) have reverted to biological human form. They receive a call to a final refuge called “Utopia” and the Doctor helps them to escape one dying world at least. He notes in passing that the human race reverts to classical form time and time again, even after spending billennia as computer uploads and plasma clouds.

In “The Sound of Drums” and “Last of the Time Lords” we learn that the refugees on Utopia were ‘rescued’ by the Master, made into psychopathic cyborgs and brought back to 2007 to exterminate the current human species, to replace them and make an Empire ruled by the Master. So “We” morphed again.

But what might really happen?

Greg Benford does quite a good job of imagining how diverse genus Homo might become after a billion years in his “Beyond Infinity” – he has hundreds of human derived species being revived out of gene vaults after a long period of stasis self-imposed by Homo superior. I think self-directed evolution might mean that something like the human form can be retained into an arbitary futurity (like 100 trillion AD), but that by no means implies stasis at the molecular level. I personally can imagine lots of molecular level machinery gradually taking over from old-style DNA/RNA – which is a bit too labile for high radiation environments and odd chemistry. Life extension would demand something more stable since cancer and aging are both caused by breakdowns in DNA/RNA replication fidelity after too many cell generations.

“Smart matter” cellular machines might be required in the long run, addressable by a body’s operating system and able to undergo a degree of “morphing” into useful configurations – we would become our own tool-kits, assimilate silicates and metals, replace calcium minerals with carbon nanotubes, and augment biochemistry with higher energy density power-sources. Technology and biology will merge – if we are to survive in any kind of physicality in the billennia ahead.

That’s how I see our evolution panning out. Frank Tipler, in his “The Physics of Christianity”, believes we will all become Uploads, of necessity – even after the Second Coming of Jesus. Maybe. After all JC said “Flesh and blood can not inherit the Kingdom of Heaven” and “sons of the kingdom will be like the angels, neither marrying nor giving in marriage” – sounds much like a non-flesh based existence to me. But bodies will always be useful regardless of how portable the software we call “the soul” becomes. I think even our Uploaded descendants will still take classical human form as the need arises. There’s a lot of information processing potential in the dimers that make up cytoskeletal microtubules – our bodies are “stupid” because we don’t yet have an interface or an OS that can utilise that power.

My Problem with Tipler’s Thesis

My issue with Tipler – the Singularity. Not with the idea that God is the Singularity, as that has too many resonances with theology, both Christian and Kabbalistic. No problems with his Trinity concept either, as I am quite happy believing in God’s Triunity.

The real problem I have is when Tipler claims that Physicists are evading God by wanting to get rid of the Singularity from GR, particle physics and quantum cosmology.

The crazy thing is that Tipler mentions a few examples of singularities appearing in physics equations and how physics avoided them – for example the Hamilton-Jacobi equations of classical motion produce singularities when applied to wave motion, a ‘fault’ corrected when Schrodinger developed the full equations of quantum mechanics. One consequence of that successful singularity evasion is the Many-Worlds Multiverse that Tipler’s theories rely on heavily.

Another example is from the assumption that particles are infinitesimal points – that produces infinite field strength as the particle is approached infinitely closely. Feynmann ‘solved’ that by demonstrating shielding of the naked charge by virtual particles.

Another mentioned by Tipler is the extraction of infinite energy during gravitational interactions between particles – if there was no upper speed limit on interactions. But because lightspeed is that limit infinite interactions don’t occur.

Now if the success of modern quantum physics is based on “eliminating” singularities, then why is it an ‘evasion’ by physicists when they develop supersymmetry, String theory, Loop quantum gravity and so forth? Tipler, perhaps rightly, condemns all those theories as baseless theorising because they have no experimental backing (yet!)

But theoretical work surely precedes experimental work when we’re talking about such extremes of energy. Yet Tipler claims that physicists have religious issues with the idea of real Singularities in General Relativity and quantum cosmology – how can eliminating singularities in one area of physics be a successful method, yet be a manifestation of ‘the Gnostic heresy’ (as Tipler puts it) when it’s applied to cosmology?

Now I believe in Tipler’s Omega Point Theory and that means I have to accept a Singularity at the end of time, and the beginning, and All presents too. He could be right, but to excoriate modern physics as ‘Gnostic heresy’ because it seeks understanding beyond those cosmological singularities is a bit much.

And if the Large Hadron Collider produces supersymmetric particles? What happens then? Will Tipler abandon his faith in physics as he understands it?

I see a rather strong parallel with Aristotelian physics. Aristotle placed God, the Prime Mover, at the Cosmological boundary of the World – the outermost sphere of the heavens was propelled by the eternal, self-contemplating Spirit/Soul. Tipler’s Trinity is the cosmic boundary of the quantum Multiverse and governs its evolution, just like the Prime Mover’s perfect motion ‘governed’ the spheres below. Modern physics evolved because people were willing to think outside of the conceptual cage that Aristotelian beliefs created. Cosmological Singularities might be pointers to similar conceptual cages.

There are so many unanswered questions in the physics that Tipler wants us to adopt as proof of Christianity’s Trinity – why the particle masses of the Standard Model? What is mass? What is charge? What is information? What is consciousness?

None of these important questions even remotely gets an answer. No Christian should ever say that their belief gives them all the answers, and in light of that it shouldn’t condemn thinking outside what is known with certainty as ‘Gnostic heresy’ either. That’s the ‘kiss of death’ for meaningful scientific endeavour, which Christianity – in its worst moments – has been condemned for.

Tipler also discusses Darwinism and the idea of ‘randomness’ in mutation, applying similar terms of abuse. Personally I think he utterly misses the point of the word’s use in biology, which is no surprise coming from a ‘physics fundamentalist’. Biologists mean that ‘random’ variation/mutation is random because it doesn’t produce genetic changes that are perfectly adapted to the environmental pressure that is acting as the ‘selecting force’ on a population of genes. Genes change because of basic physics and chemistry NOT because an animal has to run faster, nor because a plant has to grow quicker on less light. Mutation occurs all the time in genomes and is assumed to be non-directed towards useful changes.

But that picture is inaccurate too because modern genomics research is showing that genes themselves can be deliberately mutated by a body when an organism is facing an environmental stress. Thus there are regions of ‘hypermutation’ which produce new antibodies when we have an infection, and hypermutation in microbes when they’re facing starvation. This doesn’t mean the mutations themselves are perfectly fit – they are, as far as human science can tell – random. But a population of genomes that are hypermutating dramatically increases the odds for a perfect adaptation to be found to an environmental stress.

So in the end I have so much to agree with Tipler on about cosmology and physics, but so much I disagree with about his personal struggles with modern physics. And as he freely admits that’s the real source of his personal career problems and – as I see it – personal bile-spitting that mars what would be a working theory of Christianity’s truths otherwise.

Hominids go Weird

Ancient human ancestors and cousins are a lot more diverse and weird than 20th Century discussions led us to believe. Dmanisi and Flores have shaken up the palaeoanthropological world like a Richter 10 earth-quake. Why so?

(a) Dmanisi blurs the line between Homo habilis and Homo erectus by being a mix of ‘primitive’ and ‘advanced’ features. Almost a perfect example of a transitional population. Old and New at Dmanisi

(b) Flores is a real shaker because the species was so close to us in time, the brain was so small, the tools so advanced, and now it has been revealed the post-cranial material is displaying very primitive features. Hobbits had Archaic wrists

…plus there was the recent find of a very small Homo erectus skull from what seemed to be a fully grown adult. An almost perfect African precursor to hominids like floresiensis and georgicus. Things have gotten weird and may well get weirder. We may find “little people” like the Hobbits almost anywhere.

Tipler’s Main Thesis

The real meat of Tipler’s book is his discussion of the nature of God and physico-mathematical proof of God-as-Trinity, thus proof of Christianity.

Tipler argues that God is the Cosmological Singularity of Feynmann-Weinberg Quantum Gravity, and the development of String Theory, Brane-worlds, Smolin Loop Quantum gravity and so forth are actually the evasion of the FACT of the existence of God by modern physics. Physicists can’t handle the real existence of the Singularity as implied by both General Relativity and the Multiverse of quantum theory applied to cosmology, because Tipler believes they’re in denial about the existence of an entity beyond space-time yet described by the laws of physics (the Singularity is Beyond, but connected to our Multiverse.)

So that’s his basic thesis – God is the Singularity pointed to by Quantum Gravity applied to cosmology. And that Singularity manifests, mathematically, as three ‘hypostases’ – the All Pasts Singularity, the All Presents Singularity, and the All Futures Singularity. He equates these with the Holy Spirit, the Son and the Father respectively. Thus God is a Trinity and (Orthodox) Christianity is objectively true.

Next post: my main issue with Tipler’s argument.

Physics of Christianity – a critique continued…

Frank Tipler’s latest book “The Physics of Christianity” makes a basic claim: Christianity is – potentially – a branch of physics and thus testable. Tipler defines miracles, not as violations of physics, but exemplars – miracles are unlikely, but spiritually significant natural events. They NEVER violate the laws of physics, they DO violate our human level expectations.

So what does Tipler claim? There’s a few historical claims, but they’re pretty minor. Here’s a few:

(1) He makes a case for Jesus’ Virgin Birth as being due to a parthenogenically produced diploid oocyte. Which isn’t that hard to induce in humans, apparently. He was an XX, thus no Y chromosome was required. What makes his case special – XX males aren’t too rare – was the transfer of all the male genes from the Y chromosomes of Mary’s lineage to the X chromosome – something that happens perhaps once in every 20,000 women per gene. For all the Y genes the odds are massively unlikely – thus miraculous by Tipler’s definition of a miracle.

(2) A supernova in Andromeda was THE Star of Bethlehem. He makes a pretty good case for this scenario and is well aware of all the competing theories, incorporating a few into the bigger picture.

(3) Modern day miracles of conversion are explicable by ‘natural causes’ (i.e. God’s laws.) Thus casting out of demons, visions of Jesus, raising the dead and miracle healing – all
have physical explanations. Respectively: ‘demons’ are like computer viruses of the mind (think: MPD), and exorcism is like a virus quarantine; visions are information from God; the ‘dead’ are resuscitated from suspended animation, not restored from rotted flesh (though see later), and healing is via mind-body interaction, otherwise known as the ‘placebo effect’, but induced by prayer and faith.

(4) The Shroud of Turin and the Sudarium of Oveido possibly preserve real evidence of Christ’s resurrection via ‘reverse baryogenesis’ turning his baryons into neutrinos, thus uploading him into God. Both the Resurrection and Mary’s Assumption might also be testable by particle tracks in the rocks that formed the Holy Sepulchre and Mary’s Tomb.

And so on…

The big stuff is a bit more involved. Coming soon in my next post.

A first pass problem with claim (4) is that Tipler focuses a lot on the theories of Garza-Valdez on how a bioplastic film wrapping the threads of the Shroud’s cloth has caused the C-14 dating of the Shroud to be in error. Ray Rogers, whose work Tipler mentions briefly, strongly criticised Garza-Valdez’s theories and Rogers’s work on the C-14 sample area has made the bioplastic theory an irrelevance. The C-14 sample area was material different in chemistry and age to the rest of the Shroud – it was a Medieval patch, woven into the main body of fabric using invisible reweaving. Why it was chosen rather than random bits of the Shroud is unknown, but it has confused the scientific picture of the Shroud utterly.

Whedon’s ‘Verse

Joss Whedon’s “Firefly” reflects Joss’s disinterest in science in a subtle way. As a series it got so much right, like no noise in space, but it does have a few oddities from the point of view of Hard SF. Aside from that weird space-drive, I mean.

For example, the terraformed moons & planets of the ‘Verse are said to have had their atmospheres and gravity fixed by the terraforming process. Atmosphere is OK (in decades, mind), but gravity?

Here’s a speculative, but hopefully Hard SF take on fixing a planet/moon’s gravity. Question: without adding mass how do you increase a planet’s surface gravity?

Ans: Shrink the planet.

Consider: materials under compression increase in density. Intense gravitational and electromagnetic fields, perhaps even strong nuclear fields, cause materials to compress into denser forms. Some such are metastable, like diamond too, thus remain dense after the pressure subsides. Some fretful types still worry that particle accelerators might create bits of quark matter (strangelets) which can catalyse catastrophic collapse of the Earth to nuclear density. There’s several reasons why that’s unlikely, but what if there was a nuclear process that can collapse a planet’s metallic core and leave the silicate mantle?

The energetics are actually in favour of that occurring since shrinking a mass releases gravitational binding energy. If ‘Verse engineers found a way of shrinking a metallic core to 0.1% of its previous size then a planet would contract and its surface gravity would increase. At the core/mantle boundary the core’s gravity has increased 100-fold, thus enhancing compression of the silicates of the mantle.

How much would gravity increase? To double the surface gravity a spherical body would need to shrink to 70.7% of its previous size. Doesn’t sound like much, but it means the average density increases by sqrt(8)= 2.83. Escape velocity increases by just 19%, but that’s a second-order problem. Earth, so shrunk, would be just 9,010 km across.

One result I can’t parameterize is where the released gravitational energy would end up – some would become heat and probably melt much of the mantle, but that might be needed to create volcanism and revive a magnetic field. The rest would end up in the chemical bonds of the new high density phases of the compressed mantle.

Anyway there’s a new trick to add to fiction: compressed planets. I’m sure someone can imagine a way of limiting strong nuclear material, like quark matter, to just compacting a metallic core in the 500 years between Now and the ‘Verse.

Retrocausality experiment

John Cramer is a physicist at the University of Washington, and he has a plan for signalling backwards in time via quantum entanglement…

What’s Done is Done… or is It? (at New Scientist)

…which is well explained by the article, for a layperson, but from a physicist’s point of view here’s John’s own papers available online…

An Experimental Test of Signaling using Quantum Nonlocality

…of course there’s a few assumptions involved. Firstly, the quantum entanglement is caused by a forwards-backwards-in-time handshake between the interacting particles – John’s own Transactional Interpretation of Quantum Mechanics. If instead the Quantum Multiverse is correct then the experiment might have a totally different outcome. Maybe. John’s Interpretation is mathematically equivalent to the Multiverse because both reproduce the mathematical formalism of quantum mechanics… but the Multiverse doesn’t feature retrocausality.

Could John’s retrocausality experiments be proof or disproof of the Multiverse?

John Campbell’s Solar System

Seventy-one years ago John Campbell, future pivotal, legendary editor of “Astounding/Analog” SF magazine (1938-1971), was just another writer – actually two because he used “Don A. Stuart” as a pseudonym. He was fresh out of University with a physics degree and embarked on a series of monthly fact articles about the Solar System that lasted 18 months. Even 71 years later the series is surprisingly insightful and not woefully dated, unlike the fiction from the same era.

John Campbell’s Solar System

One particularly striking bit of ‘alternative history’ is this little passage…

IN 1666 the hated fourth law of light attracted Newton’s attention, and he tried an experiment to prove that white light is a blend of colored light. He admitted sunlight through a round hole to a prism, getting then the familiar colors, ranging smoothly, gradually, featurelessly, from violet through blue, green, yellow, orange to red. By means of a second prism he showed that they could be recombined to a beam of white light. Newton proved white light was compounded of colored. It was a great discovery.

For the fourth law of light is the law of the spectroscope. By it, to-day, the secret language of light may be read; by it, light talks like a garrulous old maid at a gossip’s tea party. It tells all the secrets of the universe. By it we can analyze the Sun and the million-billion-mile-distant star; we sample the air of Jupiter and Mars; and we time the speed of the moving stars. By it we analyze the minerals of Earth or star.

In 1666 America was a howling wilderness, where Puritan Pilgrims held on by tooth and toenail to a narrow strip of seacoast. England had just overthrown Cromwell. Men sought unicorns for their magic, cure-all horns. Oxygen was not to be dreamed of for a century and more. Chemistry, the basis of modern civilization, was alchemy, and men sought the philosophers’ stone.

In 1666 Newton, the man who developed the law of gravity from idle speculation on a falling apple, used a round opening to produce his spectrum, and got round images of the Sun in every color, smoothly overlapping and featureless. A spectroscope uses exactly the same apparatus save that they have a thin, hairline slit, so that each color is thrown in a hairline, sharply distinguishable mark of light.

Literally, by a hairline Newton missed the spectroscope. Had he used a slit, the spectrum of the Sun would have been bright colors crossed by mysterious black bands and lines. He could not have left that mystery untouched. He would have found that sodium thrown on a candlewick would produce bright-yellow lines matching exactly two powerful dark lines in the mysterious solar spectrum. Calcium would have given him red lines, copper and other metals —

Chemistry would have started up like a stung rabbit from spectroscopy, not test tubes! Oxygen in a year, not a century and a half. The elements of the rocks in months.

But spectroscopy waited untouched from 1666 to 1802. Can you conceive what an alien world this might have been had a man who mastered gravity, calculus and the laws of motion used that slit, the one great thing that challenges gravity for supremacy in teaching mankind?

…a particularly appropos alt.history as Newton investigated alchemy thoroughly to try to discern the fundamental laws underpining its concrete findings. In the end he failed and chemistry needed almost 150 years for Dalton’s atomic theory to revolutionise its methodology and organise its finding’s with an over-arching conceptual structure. But what if Newton had discovered the absorption lines in the spectrum first? Incredible scientific advances would have occurred 170 years early and the world would’ve had scientific chemistry before the Industrial Revolution, perhaps bypassing many of the dead ends.

Postscript

One downside that occurred to me, if chemistry arrived early via spectroscopy, was the fate of SF. Much of the early excitement of science fiction was the prospect of nearby alien life on the planets. If Campbell could pronounce the Solar System mostly dead in the 1930s after the first spectroscopic examinations of the planets, then early spectroscopy might have strangled the babe in its crib. Knowing the planets to be utterly unlike Earth by 1800, say, would have led to the still-birth of spaceflight. Missiles might have been developed, and flight, but with nothing to visit nearby, the major impetus behind the western inventors of the Space Race – the thought of Martians and Venusians amongst American, British & German space enthusiasts in the 1920s-40s – might have killed their efforts. No Goddard, von Braun, Ley, Oberth, and Clarke, to name a few.

But that may not have been the ‘kiss of death’ I’ve imagined for Russian space enthusiasts – Tsiolkovsky was of the opinion that ETIs were rare in the Universe, but that did nothing to dampen the passions of Russian wannabe cosmonauts. Perhaps the Soviets would have developed liquid fuel rockets before the Nazis? That alt.history would have been very different indeed with Stalin’s Russia bombarding the upstart fascists with Tsiolkovskyan liquid-fuelled missiles…