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Ken Fabian

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Everything posted by Ken Fabian

  1. "Feminist" is a broad category - in many cases it just means wanting things like equal opportunity of wages, legal rights, freedom from sexual harassment. It is not going to determine sexual preferences beyond being likely to make men who do not support such equal opportunity less compatible as life partners. I would not call men supporting such things "feminine".
  2. Such settlements in wilderness have no expectation of becoming self sufficient. They import almost everything (apart from air and water) from the greater Canadian and global economy and don't even directly use the minerals they mine. Were that greater economy to vanish or be out of reach they would be in serious trouble, even with foreknowledge and prepperation; an ability to survive, maybe, because there are natural, if limited, food resources and ancient experience to draw on. Sustaining advanced technology and a lifestyle dependent on it? A lot harder. Such outposts can be steps on the way to self sufficient colonisation but are insufficient in themselves. They need stuff to sell to that greater economy. Motivations do matter and I don't think making a "Planet B" for backup is a viable one; they need broad ranging commercial viability or else such colonies will, like mining outposts in wilderness, run down when the saleable resource runs out. I think "Planet B" thinking might be a longer term contingency consideration for any greater Earth (meteor) Defense type projects, the way it enters the thinking of military forces with deep bunkers - tacked on to a broader motivation that has substance - but I cannot see it being a primary objective. Elsewise we are talking about living in space being easy because we have achieved such advanced tech and wealth that living in space is easy, like jumping in the campervan for a road trip because we can, with no requirement to pay our way - in which case I wouldn't want to be stuck to Mars or any other colony planet. Visit maybe. We are way, way, way short of that.
  3. I don't think Stephen Hawking was ever a reliable source on how long humanity has left on Earth, no matter his brilliance with respect to black holes and cosmology. I think the reality of moving to space is not anywhere even close to being a viable option - and without a healthy wealthy Earth economy, not likely to ever be one. Failing to go all out to fix our problems here will ensure failure to establish a reliable, colonial foothold in space; space colonisation is not an alternative to Earth, it depends absolutely on Earth. If it achieves true self sufficiency, that will be an emergent outcome of success as an enduring part of Earth's greater economy. What I think with respect to our looming doom is we face the prospect of our civilisation - such as it is - failing us in the face of cumulative problems. Good governance looks thin on the ground to me - and large elements fiercely resists deep, long running foresight and planning. Any collapse of what we see as civilisation won't be the end of humanity by any means, but it likely will put all grand space dreams on hold and make getting back to the wealth and prosperity we now enjoy much harder in any distant future - and what we have is IMO probably unsustainable and overly a product of and dependent on resource over-exploitation in the present at the cost of future resource availability. I am not sure that unrealistic optimism about space and abundant space resources helps with keeping our eyes on this road, hands on this wheel. I am not optimistic either way - because I think it wasn't planning and foresight that got us the civilisation we have here on Earth but for getting space colonies on a sustainable footing the minimum population and economy and infrastructure needs to be very large to be able to reach reliable self sufficiency; self sufficiency in space will be very hard to achieve without those natural ecosystems to do so much stuff we depend and thrive on for free. I don't think space - even being more optimistic even than most optimists - will ever offer mass migration opportunities; mostly the idea seems to be a smallish number get to colonise space, to go on (we hope) to survive and thrive there and Earth's population gets to survive or not (we hope not) as the case may be. We are suppose to be vicariously comforted by this - enough to not resent paying for it. I remain unconvinced that this "some will survive" motivation can be sufficient to support the scales of construction and investment a viable space colonisation program needs. And we could (real possibility) see significant population decline here on Earth - whether we want it and plan it (still possible, over several generations), or not (possibly catastrophically). Interstellar colonising would be much, much harder than Mars - and I think Mars is still way beyond our capabilities. And Mars would be much harder than Asteroids. And those are still extremely hard. I would probably go for Asteroids and free flying space habitats over planets.
  4. The line between spacecraft and space station/habitat blurs but I can't see even attempting terraforming without an existing full capability of living in artificial space habitats, using asteroid/cometary - ie non-planetary- resources; ie that if we are capable of doing so we will not need to. So terraforming planets is going to be optional. I think terraforming lifeless planets will be extremely unlikely and candidates are more likely to be planets with simple life and atmosphere's not too different; ie kill off what is there and supplant it with selected/engineered terrestrial life. And I think that any non-terrestrial life presents both extraordinary opportunities (for study, for potential biological materials and biochemical processes) and extraordinary challenges - cross contamination, disease, parasitism, allergens, poisons. And a very big ethical dilemma. Like I said I think any future humans capable of doing it will be capable of thriving without doing it. I think multi-generation spacecraft won't last long enough or be capable of carrying everything they need and will need periodic resupply, refitting, whole rebuilds and - if population grows - new builds. I think that the most achievable kind of interstellar travel will be thousands of generations of hopping from deep space object to deep space object, each time building a local economy and population capable of doing that resupply, refitting, rebuilding; as I've said elsewhere I think nothing short of a large, advanced industrialised economy (and population) can manage the complexity and exacting standards that kind of high tech existence requires. Which view is a key deviation from most of the optimists. Whether a clear goal could be sustained that focuses onwards exploration and occupation of DSO's in a target star's direction when DSO's, not planets, are the source of all resources is a question. Indoctrination and social conditioning? I think some serious ethical questions arise when considering some of the possibilities. I do think that for enduring safety and security, that space habitats will beat any planets barring Earth. Earth still beats all of them and probably will for millions of years yet.
  5. Studiot - I said - You say - I think pressure would approach equilibrium - and become effectively static, barring transient variations from pressure difference based air movements. And those would average out, even if they don't maintain a perfect equilibrium. With respect to the initial question I think heat is only relevant to pressure at the centre by changing the density of the air column and by that, the weight of the air column. Heat flow within a (not insulated) borehole/tunnel? Yes, it must, through conduction, convection and radiation but I think heat profile along the air column would still approach equilibrium over time as well, more slowly for a narrow borehole, more quickly for a large diameter tunnel that allows more convection - which I would expect to be the principal means of heat movement. Thinking it further, convection would lead to hot air emerging from tunnel ends - but it would also draw in cooler surface air. Probably not a plume. And I would expect this outcome would still lead to an on-average, depth dependent, temperature equilibrium within the air column. With a through to other side tunnel - effectively two tunnels linked at the core - a continuous flow could be generated but off the top of my head (as most of this is) I would expect that the rate of air flow would have to be high enough that maximum air temperature is not reached before crossing through the centre - that it must continue warming (and losing density) on the way back up, in order to maintain the different densities to generate convection flow. For a continuing flow of air outwards you do need a source of colder air that undergoes heating, to generate expansion and lowered density. That has to come from convection within the tunnel or a continuous flow through from one end to the other. Some of this must depend on how the initial hypothetical conditions occur - a tunnel appearing magically, fully formed... but if it starts filled with air, is it surface temperature air? That would involve immediate expansion - and flow of air out both ends... until equilibrium. I wouldn't expect strong one way circulation - in one side, heating along the length, to emerge out the other without some significant other factor to get sufficient flow happening.
  6. I think the question is pressure for a lined borehole, a tunnel with walls that hold back the pressure. Or else the question reverts to what is the pressure at Earth's core, sans borehole.
  7. I don't think that would be true; there is no source of air at the core to support a plume. Nor for flinging air out. I think it would reach pressure and temperature equilibrium and become effectively static. Air movement from convection can occur within the tunnel and changing weather based pressure differences at each end would generate air movements. Given the distances those air movements might be more like sloshing waves along the tunnel, generating their own small transient pressure variations.
  8. If all the ice sheets melt, about 70m of average sea level rise. Counter-intuitively the sea level closest to where the ice loss occurs will drop, with the highest average rise at the greatest distance. The sources would include Greenland and other glacial ice that is not at the poles - but if Antarctica can melt entirely the world will be too warm to support ice sheets or glaciers. Predicting the rate of sea level rise - and therefore pin down when a specific location would be inundated - is difficult. We don't know how global warming will progress because we don't know what emissions will be; I would like to believe we can shift to low emissions energy within the next few decades. Then there are big unknowns about how ice sheet disintegration might proceed, with potential for rapid surges in sea level rise from ice sheet collapses. The current rate is above 3mm per year but has been rising - and is expected to keep rising.
  9. I admit this one does have me scratching my head. I wouldn't expect heat to change the pressure once temperature equilibrium is reached but I'm not sure of it. But if you have an imaginary borehole you can imagine it being insulated and then consider the heat separately. On reflection it is likely the heat does matter - by changing the density of the air (or plasma), which changes the weight of the air column. My first impressions left me thinking the pressure would be the same as surface air pressure but on reflection it would be SAP plus the pressure from the weight of the air column within the Earth from core to surface - and that weight will vary along that column according to changed gravity gradient - and would be less than a gravity gradient based on a point mass at the core. Maths for that is beyond me.
  10. I think in the case of interstellar colonisation - with or without autonomous, self replicating probes - incredulity is entirely appropriate and persuasive. I think the onus is on those doing the proposing to provide extraordinary proof or at least sound reasoning for their extraordinary claims.
  11. Sorry Area54 but your excess credulity that technological progress will overcome all obstacles is naive. We will hit hard limits for what technology is possible, along with economic ones where great things are possible but unaffordable. Some grand space dreams, like Mars colonies, are - I believe - possible, but unaffordable; orders of magnitude too expensive. Hypothesising a high tech solution to every problem isn't going to do it and sometimes throwing more money at a problem just wastes money. My remark about what the humans are for if the mission is run and done by AI and robots may have been flippant but any small, artificially raised population will not be in a position to step up, take charge and expect to be able to sustain tech levels that are currently far beyond our global civilisation. They will be dependent on - dependants of - tech they do not understand. Using tech we don't understand may appear quite normal but somewhere there are people who understand it - who design and refine and engineer the tech us users take for granted. It sounds like a recipe for a bunch of artificially raised kids to end up in an intractable bind, where the predicted success and growth - the awesome opportunities - are never achieved. The level of living, working expertise needed to sustain a high tech civilisation - including a crucial lot of rare, genuine geniuses - across thousands of disciplines and subdisciplines is something only large, healthy and wealthy populations - and the economic demand they create - can achieve and support. AI, robotics are another layer of complexity, no matter that from the end user viewpoint it appears to make things easier; the costs and complexities are just elsewhere, ie Earth. Like a library, those supports can aid people but no matter if I have the full specs on how to build nuclear power plants or mining robots I won't be able to do it. Not without the economy and infrastructure and population with skills and experience - and the current setup we have is wobbly; assuming it goes on for millennia and all the time getting more technologically advanced is no more than a correlation; there is nothing inevitable about it.
  12. I don't think anyone should ever do that to any children. Bad enough to raise generation after generation of kids by adult choice - or indoctrination - aboard a "generation ship". Makes me wonder what they will be for if the mission is being undertaken by AI with robots? Pets? Leave aside how complex the technological capabilities would have to be and how difficult to sustain in the absolute physical isolation of a multi-generational voyage and distance from the economy that designed and made it, that this will be a much diminished branch of humanity for a lot of generations - narrowed options, not widened, and utterly dependent on tech they likely cannot understand, and only follow recipes to try and reproduce. I also don't think it will be possible to know beforehand if any target planet is suitable for being a target planet for occupation and conquest (any colonising being invasive) - or even if it is safe to breathe the air... for the humans or safe for that new world at large, exposed to the microbiome humans carry with them. Will it even be suitable for introducing potentially invasive terrestrial species, such as successful colonists might want for their gardens? The Trekkie vision seems to be of worlds with sentient occupants but would we even recognise them unless they use tech that is obvious? Any marine sentience with simple tech would probably not be visible at all.
  13. More than one wave of migration seems possible, even likely. That every wave was successful and thrived... maybe not. I recall reading about New Zealand, that the Polynesians that settled there, that modern Maori know as ancestors, found people already there, from prior visits. Hawaii likewise. Those people were not thriving and had lost their sea going capabilities. Possibly marooned? Certainly supplanted by later arrivals, possibly violently.
  14. The kids that didn't get rickets would do better and go on to have more and healthier kids as adults - bigger families - than those that did get rickets. That sounds like natural selection, not sexual selection yet mate selection would be part of it. I'm not sure how obvious any connection with skin colour would be; there will be different susceptibility to deficiency illness according to lifestyle and dietary differences as well. The more obvious mate selection criteria might be the unattractiveness of bow legged sick youths - choosing for health, not skin colour - but I suppose an enduring mate preference for lighter skins, as a sign of good luck re healthy children could emerge. But then again maybe we get coastal fisherfolk with dark skins and forest hunter gatherers with lighter skins.
  15. CO2 was drawn out of the atmosphere by plants, to become the food that human (and animal) metabolism turns back into CO2 - that part tends to balance, ie human respiration is returning CO2 to the atmosphere, not adding to it. However the energy used in farming, processing, transporting and packaging food is adding CO2 to the atmosphere to the extent that they rely on fossil fuels. Global average emissions are about 5 metric tons of CO2 per person per year - far more than respiration which is less than 0.4 metric tons per year. A more average Australian than me makes about 18 tons per year - it is humanity's biggest waste stream by a very large margin.
  16. In the face of a global pandemic... withdraw from and defund WHO and start a war with China. That should work.
  17. My own experience says my memories and imagination can evoke emotions and my emotions can evoke physiological reactions. I can trigger the reaction by choosing to remember something. Do that enough and I expect my brain will know where I am going with that and skip directly to it. I have no doubt people can trigger ASMR and other bodily responses at will - if they want to train themselves to it. Biofeedback comes to mind and I think Mindfulness type meditations can be healthy and beneficial - something I practice off and on. Perhaps for haptics - ie interfacing with our tech?
  18. CO2 that is dissolved in water allows reactions that involve Carbon to occur that don't occur in air. Life chemistry is all (mostly?) chemistry within liquid water. eg Aqueous carbon dioxide, CO2 (aq), reacts with water forming carbonic acid, H2CO3 (aq). Carbonic acid may lose protons to form bicarbonate, HCO3- , and carbonate, CO32-. Reactions involving those ions are not so difficult to initiate.
  19. Bog standard climate science deniers memes, not worth the rebutting. Goodbye Drumbo.
  20. Climate models have done very well - it is just a matter of faith amongst climate science deniers that they have not. Most people taken in by that rhetoric are not going to check. There are technologies currently existing that will allow high levels of prosperity with low emissions - it is just a matter of faith that they do not exist or using them will result in dark age poverty. It is a much promoted and nasty stereotype of climate concerned extremists that we want people to go without stuff and would welcome de-industrialisation. The reality is we can see a profound risk to long term prosperity - that would lead to widescale poverty and misery and is effectively irreversible - and we seek to address it... to prevent dark age style poverty. And the means we are pressing ahead with involve more industrialisation, not less, more technology, not less - and the technologies are best done by free enterprise industrialists and work best in democracies with the rule of law.
  21. "Habitable for humans" rather than habitable in the sense of being able to support it's own biology. Habitable for humans is going to be a very narrow subset of "capable of supporting life that is like life on Earth". Any native life would not only be of exceptional scientific interest it seems like a big assumption that human life would be compatible with the biochemistry. Surely life throws up more complex poisons and allergenic compounds than lifeless processes - besides the more obvious hazards like wrong atmosphere or getting eaten or parasitised. If we have the technology to get to the planets of other stars we won't need planets for survival purposes - but that urge to find new pastures, to occupy and possess, is a primitive one and I would not trust humans from Earth to restrain themselves if they are within landing distance of a world they thought they could conquer and occupy. Although humans with a long history of life in artificial habitats/spacecraft may not find planets or life supporting moons attractive.
  22. I think claiming CO2 decline is a current existential risk and we need mass burning of fossil fuels to save us is about on par with the "global warming is saving the world from the next ice age (glaciation)" argument; they sound convincing to people who don't want to have to deal with global warming (and don't care if the science is right or wrong) or otherwise have no clue. I am not convinced that Happer himself has done any serious research to reach that conclusion or even necessarily believes it - he doesn't accept climate science (and that is telling) and/or the predicted consequences of rising CO2 levels. Perhaps he feels that his physics background puts his guesses ahead of the expert knowledge of "lesser" scientists. His putting his oar in is a statement of political position, not science. A bit like Dyson. There is no Loss of CO2 crisis - there wasn't at the start of the Industrial revolution and we have a lot more CO2 now. It looks like an attempt to raise up a false crisis in mockery of the climate crisis, by people convinced that the climate crisis is a fake crisis.
  23. If you can find one science institution that studies climate and says it is a hoax fabricated by socialists and feminists I will be very, very surprised. You will struggle to find one that thinks the seriousness of global warming in the reports and studies commissioned by governments, including the IPCC reports, is being overstated. That they are in agreement is due to multiple independent studies reaching the same conclusions, not conspiracy. We have had more than 3 decades of governments choosing stepping back and re-examination of the issue rather than face up to it; doesn't matter if they are Progressives or Conservatives, the science advice remains effectively the same. If you cannot bring yourself to read the IPCC's reports - or just the summaries - you could try the UK's Royal Society or US National Academy of Sciences - both long running science institutions with well earned reputations for integrity as well as competence; they draw on the very best experts in the world to make sense of complex science for policy makers and public. If you want sources that tell you it is a hoax fabricated by socialists and feminists I'm sure you can find them and you are probably entitled to choose to believe whatever you like - but for people holding positions of high trust and responsibility to turn aside from science based expert advice it is seriously irresponsible and negligent. I think encouraging the kinds of conspiratorial thinking that seeks to blame socialists and feminists and environmentalists and globalists and scientists in place of facing up to it - for political or personal advantage - goes beyond simple negligence and becomes potentially criminal negligence.
  24. Leaving aside the commercial opportunities from satellites - Earth based investors, Earth based customers, no (very expensive) astronauts - where are the private enterprise opportunities that subsidising space industry is intending to open up? It is still all (but for a tiny unsustainable part) payed for by taxpayers - and I am not seeing this emergence of private enterprise commercial opportunities from manned spaceflight apart from competing for government contracts. The big contracts they appear to be tooling up to chase are manned Moon and Mars missions, largely justified as steps on the way to colonies. They are not chasing real commercial opportunities on Moon or Mars; there aren't any - they are money sinks. The companies involved are sources and promoters of Moon and Mars colony hype in a circular arrangement. I don't think that is a good foundation to build on. Popularity of grand space dreams drives the taxpayer funding. The private industry part is built on chasing government contracts, with strong incentive not to look too closely at the assumptions built into those dreams. I really want to see some genuine commercial opportunities that can make space enterprises self sustaining, not taxpayer funded grand space reality TV.
  25. That is a fair point. Although I think not all government contracting is equal; I think fire hose makers and cleaning companies would exist outside of government contracting but launch capabilities for astronauts would not. Whether it is good use of tax money, like Prometheus said, becomes the question. Cleaning offices and supplying fire hoses gives tangible and prosaic benefits.
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