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Wormholes and Singularity

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Published on February 3, 2007, by in Starflight.

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

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Published on February 1, 2007, by in Starflight.
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!

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Published on January 31, 2007, by in Uncategorized.

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

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Published on January 31, 2007, by in Anthropology.

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

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Published on January 30, 2007, by in Anthropology.

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.

 

Getting used to this blog

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Published on January 30, 2007, by in Starflight.

This is so weird. Got to get used to the time stamps and figure out how to change the timezone the prog is working from.

Anyway how are we all out there in the Blogoverse?

I’ve got an old blog in a different domain which you might like to glance at. I’m thinking of haulling posts from over there to over here, but editting my old junk might be more labour than it’s worth. I was quite surprised by how decent some of the posts are, but then I’m hardly objective am I?

http://crowlspace.blogdrive.com/

Of course you might be wondering when I am going to continue certain lines of discussion from the old blog, such as what I meant about not building Daedalus out of free-space materials.

Neptune has Triton, but it also has an inner moon, Proteus, which is probably full of metals too with an easily accessible core.

Strange real estate, but that’s what building a Daedalus would take. Or maybe not…

…which I meant to be a teaser. Daedalus’s structure mass is quite low, amenable to launching as pieces via a Heavy-Lift Launch Vehicle (HLLV) and in-space assembly. I’m sure, if we really tried, the unfuelled vehicle could be launched all-up as a unit via some beefy HLLV using nuclear thermal rockets, but even chemical boosters can launch 150 tons a throw without too much pain. And up to 450 tons has been designed and considered feasible.

The real issue is that many of the components are large – the beryllium shield is 50 metres across, while the propulsion bells are huge too, though light-weight for their size. There’s over 700 tons of propellant mass, other than the main tanks, which beefs up the probe’s ‘dry’ mass budget. If we could get all the volatiles in space then the task gets easier. Of course the real question of probe design is whether a 450 ton science payload makes any sense. That’s what drives the mass budget overall.

 

Photosynthesis as we don’t know it

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Published on January 17, 2007, by in Carnival.

Photosynthesis powers our biosphere and without it we’d be rather short of breath, but oxygenic photosynthesis is a tiny subset of what life has tried. In bacteria there are many different photoreactive molecules and several different photosynthetic processes – some use water as the reductant (hydrogen source), some use hydrogen neat, and some use hydrogen sulphide. Also the photosynthesis we know and love in familiar plants is quite fond of two rather narrow frequencies of visible light, but it’s possible for biomolecules to grab several photons of light to get their power-boost from near-infrared (NIR) in the 1000 to 1400 nanometre wavelength range.

So what does this imply? According to these two studies…

Spectral signatures of photosynthesis I: Review of Earth organisms

…and its follow-up…

Spectral signatures of photosynthesis II: coevolution with other stars and the atmosphere on extrasolar worlds

…it means that M-dwarf stars can sustain oxygenic photosynthesis and might even allow land-based life, if their flares are of the milder variety. Most M-dwarfs flare – rapidly increase in x-ray and UV brightness for brief periods – but some flares are milder than others. A proper atmosphere is quite able to absorb harmful x-rays, but a bit of UV gets through, enough to inhibit life – but even the largest flares will only penetrate about 9 metres into water with their UV, so oceanic life is quite safe.

An who’s to say that life can’t adapt to UV and even find it useful? Perhaps by incorporating more metals into their metabolism organisms might usefully trap UV energy for biological processes?

In more immediate terms what it means is that we can fairly confidently hope to find habitable planets around even the smaller variety of stars – and since M-dwarfs make up 75% of stars in our immediate neighbourhood that’s a good thing.

 

This is Rocket Science

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Published on January 13, 2007, by in Carnival.

Adrian Mann is an awesome digital artist who has visualised some of the classics of spaceflight studies of the last 35 years…

This is Rocket Science

…some notable creations are Starship Daedalus

Starship Daedalus

…which is very cool. And another ‘blast from the past’ is Project Orion

Project Orion

And the ultimate starship design, the interstellar ramjet

Bussard Ramjet

But there’s some near-term designs from the 1960s, aka the Nerva nuclear thermal rocket and its associated Mars Mission

Project NERVA

A PROFAC (Propellant Factory) from the early 1970s (studied by ELDO, the European Launcher Development Organisation, parent of the ESA)

PROFAC and Space Tug

…the Space Tug design is from a European study on early Lunar access using European and NASA hardware. In Adrian’s visualisation we’re seeing the Luna Landing kit deployed, plus an add-on Crew Mission Module. For interorbit operations the Space Tug would have neither and would dock to a cargo module or another Space Tug operating as a booster stage. Fully fuelled a Tug would mass 12.5 tons, with a burn-out mass of about 1.8 tons. According to Marcus Lindroos this is well within state of the art. By comparison NASA-studied Tugs massed 2.5 tons dry and 20.8 tons fully fuelled, with an extra 4.4 ton CMM for a 3-man 50 day mission.

 

Brain Reading Remote

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Published on January 13, 2007, by in Carnival.

Hitachi have developed a brain-reading device which uses near-IR light to watch blood-flow in the brain – a proven proxy for simple, strong thoughts.

Hitachi’s Brain-Scanning Remote

In essence you’d wear a near-IR pick-up as a head-band and it would allow you to think simple commands on a remote control. They’re hoping to market to disabled people, but I can see the idea spreading and being refined to give us ‘thought recorders’ and the like. The US DARPA worked on sub-vocal communicators for a while which sensed the impulses to the vocal-cords which occur when we’re “talking in our heads” – I’m not sure how well that project went, but it would also allow for ‘thought recording’ or at least a sub-vocal Dictaphone.

Will we have it first appearing as a hobbyist craze – ‘stick to your head Thought-Buttons’ – advertised with telescopes and computer projects?

 

Eavesdropping on ET II

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Published on January 12, 2007, by in Carnival.

Space.com has a news article covering the claim that we’ll soon be able to “eavesdrop” on ETs…

Eavesdropping on ET soon

…which would be fantastic if it happens and disquieting if it never happens. But detection may not be easy. Even the Square Kilometre Array will be hard-pressed to pick a signal from more than a few hundred light years away unless it’s a tight beam, so if ET is thinly spread out They will be drowned out by the Galaxy’s natural radio ‘noise’.

To make ET more prevalent, the argument goes, we might assume they’ll go on to colonise the Galaxy. Galactic colonisation and exploration has rather glibly presumed to be ‘easy’ – even by this author – but without incredibly unlikely FTL travel the project will take at least a hundred thousand years and potentially much, much longer. Possibly the current age of the Galaxy…

Exploring the Galaxy using space probes

Many assume that as soon as intelligences can make autonomous self-replicating robots then that’s what they’ll do, sending them forth with a ‘mission’ to colonise the galaxy with their kind of intelligent life. A self-replicator smart enough to be called ‘intelligent life’ is a ‘person’ in my view, but an arguably important aspect of personal identity is freedom and creativity, and I suspect even the longest-lived ‘persons’ will fatigue in the face of a task like colonising every star in the Galaxy. A more organic expansion will be what eventually completes the task and there’s no easy way of estimating how long, or how thorough, such an expansion will be.

And why should self-replicating probes colonise at all? They’re intelligent enough to decide that for themselves, but such vastly long-lived entities may well develop a wholly different set of motivations to us organic beings. Perhaps they will rest content with lightly touching on every star, leaving a ‘clone’ to thoroughly explore and monitor every system while venturing ever onwards to new stars. Years ago Chris Boyce computed that even if the probes weighed a million tons each, a new one arrived every decade, and made a copy every decade to send off, then after 4.5 billion years they would have consumed at most the mass of Neptune. That might sound like a lot, but the Kuiper Belt is assumed to have massed maybe 100 Earths in its early days – more than enough mass for making probes, in bite-sized chunks.

And that’s with gargantuan megaton probes. Frank Tipler has spoken of 0.1 kg ‘probes’ running a virtual city of 10,000 people as software. At the same pace of replication they’d mass 1/10,000,000,000 th of Neptune by now – a smallish asteroid.

With that in mind read Gregory Matloff’s essay from a few years ago…

Re-enchantment of the Solar System

…in which he discusses ETs living quietly in space-arks in our Kuiper Belt. His case is plausible – he even provides a means of detecting ET’s heat emissions – and, if ETs are real and long-lived, then They’re almost certainly ‘here’ on the fringe of our Solar System.

That still doesn’t mean UFOs are really ET space vehicles, but it does mean some might’ve been, just maybe.