mindstalk: (science)
One recurrent debate I see is whether technological progress is progressing ever further and faster toward Singularity or something, or whether transformative invention has slowed down or mostly stopped outside of IT. (And then, in the latter case, whether Internet and smartphones are as transformative as telegraph, electricity, home appliances, and farm automation.)



A guest blog post I just read made me wonder if there's potentially transformative stuff we're refraining from out of fear of the consequences. The post/essay is on "a new technology that has made the precise editing of genes in many different organisms much easier than ever before" -- editing via an intracellular mechanism, and the precise editing can include copying that mechanism, and operation in gamete-producing cells. So you can make an organism all of whose offspring will have some high-precision genetic change you specific, including editing out genes acquired from other parents! Not just your GMO lacks some gene, but all of its descendants can lack that gene. Potentially very powerful for altering wild populations of sexually reproducing pest species, like malaria mosquitoes, or Australian rabbits, or malaria itself. Altering them by reducing fitness traits or their numbers outright, like a higher-tech version of flooding a population with sterilized males. And low risk to domesticated species whose mate choice is constrained. Not useful for asexual species so won't help the Age of Antibiotic Resistance.

Sounds pretty neat, and superficially I think we should use it, but I expect lots of hesitation, doubt, and fear. Which led to wonder what potentially world-transforming things we might be doing but aren't. Most of these aren't nearly as high tech, just cases of "the world could look a lot different if we wanted."

Ocean fertilization: just as many deserts bloom by adding water to them, so the open oceans are nutrient deserts, and may potentially bloom by adding iron and other nutrients; one study adding iron and silicon (for diatoms) thought biomass increased 1000 tons for every ton of nutrient. Good outcome: massive more amounts of fish. Bad outcome: waves of anoxic layers falling through the oceans.

Similarly, bandaid geo-engineering for global warming via adding sulfate or other particles to the atmosphere to reflect sunlight seems cheap and doable, by all accounts, though here even the best outcome is simply slowing down warming while the oceans still acidify (from CO2) and building up a need to keep on engineering unless we use the time to reverse CO2 emissions. Also acid rain if you use sulfates and not some alternative.

Eugenics research: so, we're at the point why our ability to sequence and edit genomes far exceeds our understanding of more than the simplest edits, especially for human traits. At $5000/person (a recently reached price) you could sequence a million people for $5 billion; with detailed medical and life studies, you might build up a better idea of what genes do and how they interact. Long term, you could sequence every American born for $20 billion/year. [To be fair, this isn't something we've even been able to do for long, so not really case of refraining from it yet.] If successful, the research would then drive actual human engineering.

Free and mandatory paternity testing: this could be folded into a medical genetic assay for newborns. I'm not sure what the effects would be, but seems like there should be some, to knowing that any reproductive cheating would be caught without having to imply lack of trust by asking. If combined with a national database, perhaps from the prior idea, that'd identify most straying fathers as well as mothers.

The Beta Colony implant: there's no one-size fits all solution, but between copper and hormonal IUDs and hormonal implants, arguably we could put all women on some form of long term contraception from puberty, reducing accidental pregnancy and unwanted children to near zero.

Keynesian 'technology': I think it likely that we could sustain full employment most of the time, with economic power shifting from capital to labor, and inequality falling, just by listening to Krugman et al., and unlike more radical ideas like full basic income or Communism the social risk seems pretty low. Arguably, so's the transformation potential, but still: US GDP being 10% higher, median income being even higher than that due to income distribution changes, workers not being terrified of their bosses or of unemployment.

Similarly, carbon taxes to internalize pollution costs, and market price parking, would make a big change, though here we can say "would look a lot more like urban Europe or Japan."

Space?: No, I don't include this. We aren't choosing not to exploit space resources, it's just hideously expensive to do so. We *could* have more telescopes and orbiters and rovers, which would bring in a lot more data, but this isn't a high-certainty way of changing our lives a lot.

mindstalk: (Void Engineer)
I wouldn't have recalled that interplanetary radar has been a thing, but it has, and http://arxiv.org/abs/1301.0825 proposes an interstellar radar system for distant imaging. Claims no new technology is needed, just expense. Lots of expense, he estimates $20 trillion. My friend G and I had estimated a cost for Project Longshot -- an interstellar orbiter (unmanned, no return) -- of $400 billion to $4 trillion. OTOH Longshot would take over a century to reach the nearest star system and would need robust automation to match, though the uncertainties there are part of the cost (and the marginal cost of multiple probes could be lower... as low as $40 billion?) Radar could return data within my lifetime, and once built could image many nearby systems.

G likes to account for things in "war units", $400 billion or a trillion, a la the cost of the Iraq war and associated shenanigans. "We could have another war, or we could send a probe to Alpha Centauri." The radar looks expensive even in that light: $1000 per rich country person for 20 years, or $140 per global person. OTOH per capita income is $10,000 globally, so 1.4% of global GDP for 20 years. As science budgets go, very expensive; less than the global defense budget though.

I'm partly intrigued by the idea, partly amazed that there's finally a case where sending probes seems cheaper than remote observation.

This definitely calls for the Void Engineer icon and the sceince! tag.
mindstalk: (robot)
http://physics.ucsd.edu/do-the-math/2012/10/futuristic-physicists/


I wasn't happy with the answer list, but he reminded me that his instructions define "likely" as >50%, so "unlikely for humans" means basically "1-49% likely ever", given the final option of "<1% likely". Still unclear if he meant for intelligent robots to be included in humanity's direct successor species, vs. just somewhat evolved biological descendants. Makes a big difference to a lot of the questions, IMO; I assumed they did count.

It's not designed to show you your results, so if you want to post your answers pay attention. I was like robot cars in 50 years, jetback never, aircars unlikely, teleportation never, robots in 500, longevity in 500, Moon and Mars in 5000, terraforming eventually, FTL never, black hole and astrophysics eventually (robots really matter here), synth food (assuming social use, not lab) unlikely.
mindstalk: (Void Engineer)
We live on a billions-year old spaceship, shielded from natural radiation by a nuclear-powered[1] force field, and living by the emissions of a partially shielded fusion reactor. We fill birthday balloons with nuclear waste. We're mutants descended from generations of mutants. We eat greens, hoping their natural pesticides will keep us healthy, and give genitals as a sign of affection. We mostly eat the offspring of the most vulnerable organisms around us.

(Can you think of more to provocatively phrase?)

[1] Originally I had 'fission', but I'm reminded the heat comes more from spontaneous radioactive decay, not fission.
mindstalk: (escher)
I've read more of the human evolution book, but am too lazy to blog it. And while plundering the library today, I found Become and Instant Physicist, by Berkeley physicist Richard Muller, author of Physics for Future Presidents. Become is a tiny book, with left hand pages having a little science fact and the right hand pages having an illustration. It's not really "teach you physics", more "have some interesting facts". A good toilet book (as in something you can pick and put down readily, like Calvin and Hobbes collections.)

Sometimes there's a theme, one page leading to another, e.g. the first page is about radioactive C-14 in the atmosphere and organisms, and the second is about radioactive wine. Supposedly the US government has banned the synthesis of consumable alcohol from oil. I'd never thought of this before, but I'd bet converting ethane to ethanol would be easy to do and easily safe. (You have to separate a non-polar gaseous hydrocarbon from a polar liquid alcohol. That's got to be the easiest chemistry ever.) And ethanol's too simple to have chirality. How to make sure someone isn't passing off synthetic alcohol, then? Biological alcohol would be radioactive, from plants recently incorporating C-14 from the air. Fossil fuels have been buried for millions of years, when C-14 has a half-life of 5700 years. Oil and its products isn't radioactive. (Well, not in carbon, anyway.) So apparently the BATF checks booze for radioactivity, wanting it to be present. You could do the same check on alleged biofuels.

"Plutonium is pretty toxic. If inhaled, the letha does is a few thousands of a gram", much worse than arsenic or other common poisons. But botulinum toxin, the poison in botulism, is a million times more lethal than plutonium.

Electricity from a store AAA battery costs $1000 per kilowatt-hour. P=IV, I=1 amp and 1.5 volts, P=1.5 watts, for about an hour. Price = $1.50. Math checks out, I haven't checked the input numbers.

The helium we put in children's balloons is nuclear waste. It's not primordial helium like that which makes up Jupiter, it's the accumulated alpha particles from Earth's radioactivity. Relatedly, geothermal power is indirect nuclear power. Related (this is me now), the one form of fusion power we could do now would be to blow up fusion bombs underground, and tap the hot rock for heat.

The X-Prize was lame. Getting up to 100 km is easy; the Germans sent a V-2 to 85 km in 1942, and by 1946 the US hit 185 km. The hard part is staying up; orbital velocity requires 30x more energy.

Cubic zirconia is supposedly prettier than diamonds. I knew it was comparable.

The anvil shape of thunderhead clouds (cumulonimbus) comes from the warm air of the cloud rising through cool air (air gets colder with height) until it hits the ozone layer (which is warm from the ozone absorbing sunlight) and spreads out.

Hurricane Katrina wasn't that big, it was just the first Category 3 storm to hit New Orleans in the last 30 years.

Organic produce may have less artificial pesticides, but it likely has more natural ones. Farmers select varieties resistant to pests. Resistance means making pesticides. Supposedly those are more carcinogenic than USDA approved ones, too. (I add: also, plants react a lot to getting eaten. Even the same strain of plant probably produces more pesticides when it's being nibbled on than when it's being kept safe by the farmer.)

Filling a car's gas tank is an energy transfer of 12 megawatts. (A gallon has 120 megajoules -- I'd have said 160 -- and takes 10 seconds to pump.)

If you think about the optics, mirrors are as amazing as holograms. But we're used to the mirrors. Though cheap high-quality mirrors are a modern invention. "through a glass darkly" refers to crappy ancient mirrors.
mindstalk: (robot)
Inspired by a thread on plausible alien invasions.

As I think I've blogged before, in a sense we may be quite close to being technically capable of sending a ship to a nearby star. At the raw physics level, we already have the energy sources. The Newtonian kinetic energy of mass at 0.03 c is comparable to the energy density of fission fuels, and means getting to Alpha Centauri in 140 years. The tricky part is delivering the energy into exhaust of such speeds; thermal engines melt, mass drivers quench, ion drives I'm not sure about, plasma drives ditto, photon drives have too much exhaust 'velocity' to be efficient, fission fragment rockets would be just right but the atoms that want to fission aren't the ones in a good surface position to send fragments out the back.

Still, it's possible that an ion drive, or plasma drive, would in fact work. The extreme case is Project Longshot, where a fission reactor is used to force D-He3 fusion pulses, getting you the energetic plasma needed (and more, it's like a fusion afterburner) while ducking the problem of fusion power reactors being among the hardest things the human race has ever tried to do. (Here, plasma squirting out is a feature, not a bug.) And of course there's always Project Orion, another fission-fusion combination, and maybe one that could use the much cheaper D-D reaction. Or fragments.

Of course, then there's the matter of having something that lasts 95 (Longshot) to 140 (pure fission) years, in hard radiation to boot; this might well be harder than simply making something go fast. Even more so if you want to send live beings.

But... there's a common assumption that if you can send a ship like that, you don't need to invade, you can build space colonies and such. But it's not true. Leaving aside whether people want to live in space colonies, the problems are different. The ship 'just' needs to last over a century; air leaks can be replenished from ice supplies, breakdowns can be compensated for by redundancy, spare parts, and a portable machine shop; people need some combination of a few generations, stasis, or longevity (possibly including partial longevity through partial stasis, or slowdown.) While a colony needs to be more permanently robust, and to contain or have access to a complete industrial ecology.

So invading your neighbors with the desperate hope and need of taking them over, and using their labor and industry, may in fact be easier than a self-contained space colony, and at any rate is a different problem.

Another key note: the sort of "we could expensively build it soon" fission-fusion interstellar ship above does not include ground to orbit capability for Earthlike planets. Moon landers sure, Mars maybe, but for anything we could send, taking capsules down to the surface of an Earth would be a one-way trip. We don't know how to get off again without an army of thousands building the return vehicle.

And of course for any rocket a one-way trip is a lot cheaper than a planned round-trip without guaranteed refueling. And if you need lots of fissionables, refueling may be hard and chancy.

So while the probability of having near neighbors to invade seems very low, and it'd be expensive, there's actually a certain plausibility to would-be conquistadors not much more advanced than us coming and trying to bluff/conquer/trade their way in, without any option to go back home, or even get back off the surface once landed without help. Not very plausible -- but the alternatives, that anyone crossing interstellar distances must be magically more advanced, are not clearly true. You just need fission, you don't need indefinite life support (if you're counting on another ecosystem you've observed with telescopes), you can't necessarily get off the planet, or zip around a solar system arbitrarily.
mindstalk: (void engineer)
When I was a kid I got Odyssey, an astronomy magazine, which had a cartoon about the adventures of the robot Ulysses 4-11. One story had invisibility via "optical rerouting", moving or imitating photons from one side to the other.

Voila: http://www.engadget.com/2012/03/04/mercedes-f-cell-gets-led-camouflage/
mindstalk: (Void Engineer)
There are 149 million square kilometers of land, including all the desert, mountains, jungle and tundra. There are about 7 billion humans. This comes out to 2.12 hectares per person, or in snowflake units, 5.2 acres. An American football field with endzones is 5353 square meters, or 1.33 acres; a pro football/soccer field is 7140 square meters, or 1.76 acres. So, depending on where you live, everyone gets 3-4 football fields of their own.

I strongly suspect that with fire and metal tools, let alone power ones, even a wimp like me could totally deforest all that area. Probably not keep tree shoots and saplings from springing up -- that'd be what goats are for -- but chop down all the multi-year large trees and keep new ones from growing far. Also expect that with guns I could kill all the large animals I didn't want. So basically, humans evenly distributed could make all large animals and many trees go extinct, or undergo severe selective pressure.

As for terraforming in the most literal sense, you can imagine how much dirt you could schlep around your five acres. A deep grave is 2x1 meters x 2 deep, and seems doable in at least a day, if not a few hours. (2x2 x 1 deep would probably be easier.) 28 years to dig out your land at that rate. Non-trivial, but conversely the human race could turn over the Earth's whole surface two meters deep in half a lifetime. That's pretty geological. And that's people with shovels, not backhoes.

Also you get to imagine staying alive by farming 5 acres. Or, probably half of that or less, what with the mountains and deserts and tundra and such.

Earth's atmosphere is 5e18 kg. We breathe roughly 10 liters a minutes, or 15 kg/day. So the human race breathes 3.8e13 kg a year, or about 1/100,000 of the mass of the atmosphere. Okay, that doesn't seem huge.

A human's metabolic energy is about 100 Watts. An American uses 10,000 watts via various means, as do Canadians and Scandinavians. So an American is using the energy of 100 humans -- and the 300 million Americans are using enough energy for 30 billion people, and 4x the metabolic energy -- and respired air -- of the whole human race. Humans as a whole are using 1.7e13 watts, vs. American 3e12 watts, and world metabolic 7e11 watts, so with fossil fuels we're "breathing" 1/3,000th of the atmosphere per year.

There's about 3e15 kg of CO2 in the air, vs. the roughly 1e15 kg of air that we "breathe" industrially.

Average land rainfall is 72 cm/year, leading to about 14,500 m3 of water on your 5 acres. Americans use 1880 a year, about half of which is for power plant cooling. Collecting all the water that falls on your land may be a challenge, depending on terrain and climate. So, not using all the water, but definitely making a dent.
mindstalk: (science)
So, there's a couple thoughts about realistic starships. One is that we can't do them and they're centuries of tech away. Another is what we could do them, or probably good with a decade or two of engineering research, but they'd be really expensive. Most people with a clue tend to think the first. But! The second might be more accurate, at least as far as the propulsion goes. The classic one is

http://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion) and variant http://en.wikipedia.org/wiki/Nuclear_pulse_propulsion#Medusa

where you blow up nukes against a pusher plate. Advantage is that it utilizes the one kind of energy productive fusion we can actually do, fusion bombs. Disadvantage is people's nervousness about huge quantities of nuclear bombs, plus since a bomb has a minimum size, the vehicle has to be large. Which can be good if you're really out to send something big, but if you just want a probe, is problematic.

Mercy cut )

I guess the takeaway lesson is that you need nuclear energies to have even kind of crappy interstellar ships, but we *do* have nuclear energies, and throwing large but reasonable amounts of fission, and maybe explosive fusion, at the problem will suffice for automated probes, such that propulsion may well be the easy bit.

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