Sierra Foxtrot 17

SF thoughts.

• Apparently the specific energy of carbon nanotube springs is actually 7.2 megajoules per kilogram, not 0.3. Which probably doesn't mean that of boron nitride nanotube springs is 72 megajoules, not 3, since boron nitride nanotubes are more massive than carbon ones, averaging 2 grams per cubic centimeter rather than 1.35. But since I think a spring's energy is linear with respect to the mass, we can conclude that the difference of their densities (1.35/2=.675), times the difference of their stiffness (tenfold) produces the difference of their specific energy, 6.75. Which still means that the BNNT spring has a specific energy of 48.6 megajoules per kilogram, compared to gasoline's 46.4. (Though I think I, or my source, transposed some digits, because gasoline's energy density is 34.2 gigajoules per cubic meter, not 32.4. Which still means BNNT springs are competitive with gasoline.)
  
  What that means is that the zled equivalent of a UH-60 Black Hawk, using electric motors instead of internal-combustion ones, with the equivalent of 2766 kilos of jet fuel (specific energy 43 megajoules per kilogram, energy density 35 gigajoules per cubic meter) taken up by BNNT springs, has a range of 11,296 kilometers, compared to the Black Hawk's 2,221—first because its two 1410-kilowatt internal combustion motors become two 402.857-kilowatt electric ones (electric aircraft motors being 3.5 times as efficient), and second (less importantly) because BNNT springs require 11.5% less fuel mass. And if zledo had something like the JetPack Aviation JB-10 jetpack, which they wouldn't because jetpacks are deathtraps irrespective of what powers them, they'd be able to get a hair under four times (395.58%) its eight-minute flight time, over half an hour, from the same mass of power-supply.
  
  Electric cars (or tanks) are slightly less impressive; electric car engines are only twice as efficient as internal-combustion, instead of three and a half times like electric aircraft, and gasoline is only 4.5% less efficient (as a function of mass) than BNNT springs rather than 11.5% (diesel is 6.6% less). But that still lets a HMMWV with an equivalent mass of spring to its gas supply have 2.13 times the range of diesel or 2.09 times the range of gasoline, and lets an M1 have those range-improvements over gasoline or diesel, or 2.26 times its range on jet fuel. All of which is just assuming the vehicles are made of the same aerospace or automotive alloys as now, which they aren't; the frames are made of far lighter microlattice and the armor (on the tank) is replaced with far lighter metallic foam.
• For humans, lithium-air batteries—specific energy 40.1 megajoules per kilogram, energy density 37.8 gigajoules per cubic meter—are slightly inferior to fossil fuels, but the superiority of electric motors makes up the difference. A Black Hawk with electric motors powered by lithium-air batteries the same size as its fuel capacity has a range of 7,249 kilometers, and a JB-10 (which, again, they'd never use, because deathtrap), it'd get 3.26 times the range of the jet-fuel powered one. A lithium-air powered HMMWV gets 1.759 times the range of a diesel one, 1.728 times a gasoline one; a lithium-air powered M1 Abrams has those improvements to its range over the gas and diesel ones, and 1.865 times the range of one powered by jet fuel.
• I think the main artificial birth-control of the humans in my setting involves interfering at either the primary or secondary phase of ovarian folliculogenesis, probably with medical nanobots, but also artificially stimulating the hormone glands (with other medical nanobots) so that the fluctuation that's normally associated with ovulation can still happen. It's not perfect, of course, but it's less disruptive than modern hormone-based contraception. Presumably the nanobots use metadata from each other to ensure a normal hormonal cycle.
  
  Another thing they do, while interfering in the development of ovarian follicles, is perform gene-therapy to ensure that the DNA-repair genes involved in homologous recombinational repair don't get depleted, so that people who, with 24th-century medicine, are quite able to have children up into their eighties (the average age of menopause in my setting is 82, because human lifespan is 130 years) are actually able to do it. (Or at least, that's what they do for the well-informed and wealthy; it's sorta darkly ironic to suggest medical professionals would do that for ordinary people.)
  
  Actually come to think of it the main side-effects might be from that gene-therapy, what with gene-therapy being accomplished by infecting the patient with a modified retrovirus. Fortunately ovarian aging isn't something that has to be counteracted with every dose of the treatment; it's probably a "once or twice a year" kind of thing. Actually yeah, I can work with that; there's another gene-therapy in my plot, maybe I'll have the character say she's not used to gene-therapy side effects, since she isn't rich enough for the ovarian anti-aging treatments.
• Lot of possibilities for aliens in the fact puffins have photoluminscent beaks and some chameleons and frogs have glowing bones.
• It's fascinating how post-Abrams Trek doesn't so much hate science, as deny that there is such a thing. Now, it's nonsense when fans (entirely justifiably complaining about how bad Picard and Discovery are) say that the older shows were semi-plausible. They were nonsense; anyone with a high-school level understanding of science should know they're nonsense. But this new crap makes them look absolutely diamond-hard. Star Trek always had a tendency to conflate science and technology with magic, but at least it was internally consistent magic, like in a serious fantasy story for adults; post-Abrams Trek, on the other hand, is treating it like magic in a children's fantasy, like early Harry Potter.
• It seems there is an Earthly parallel to the khângây concept of ever-increasing circles of solidarity, multiple degrees of kin then compatriots than foreign allies. Anyway the term for it is asabiyya, the Arab group solidarity concept, but without the "amoral familism" that plagues Arab culture.
  
  Where the Arab saying is "I against my brother; my brother and I against my cousin; I, my brother, and my cousin against the stranger", the khângây would instead say "I help myself; I help my brother; my brother and I help my cousin; my brother, my cousin and I help our compatriot; my kin, my compatriot, and I help our ally; my kin, my compatriot, my ally, and I help the stranger". Rather than only ceasing to fight who's nearest when someone further off comes along, it's who takes priority in terms of aid.
  
  As the khângây develop into a "world government" system, they add a layer for "the whole species", and then, after first contact, "sapient life"—though their first contact was with the thoikh, so they probably actually waited till first contact with zledo, who turned out not to be dangerous and crazy.
• Searching the blog thinks I haven't mentioned it, but birds don't have blood-types. Nope. They can receive blood from exactly any bird, and the only issue is that you have to do the transfusions more often the less related the birds are—you can even do different species, genera, and so on, probably even unto paleognaths and neognaths (at which point you're probably going to have to transfuse really often, though). Decided the same goes for zledo, so character profiles will all list "N/A" for blood type.
  
  Incidentally a lot of nonhuman mammals appear to lack either universal-recipient or universal-donor blood-types, with only dogs having both (DEA 1.1 positive and negative, respectively). (Well and chimps, but they have mostly the same blood-groups as us.) Cats don't have a universal donor; horses don't have a universal recipient. Rabbits, not in that article, don't have a universal recipient either. (Rabbit blood-types, by the way, are A, B, O, S—or rather Š/Ш, they were first described in the Eastern Bloc—and L.)
• Another difference between birds and mammals is they don't get respiratory viruses, apart from bird flu, very much; most of what looks like a cold, in birds, is bacterial infections. The issue there is that they don't go away on their own, but need antibiotics. (They can also reinfect with the same illness, unlike with a cold virus. Find a good bird vet, if you have pet birds, clearly.)
  
  Zledo, I decided, do get illnesses comparable to colds, caused by a virus(-analogue) rather than a microbe (or maybe even by a prion), but with flu-like symptoms, because their pneumatized body cavity means that sinus congestion results not only in headaches but in aches throughout the whole body. (Something similar seems to happen in birds with aspergillosis, a fungal infection. Find a bird vet!)
• Discovered this researching my Pathfinder setting's dragons, but turns out, birds don't have beaks to save weight. Nope. They have beaks to save time, specifically while in the egg. Teeth take a while to form—dinosaurs spent three to six months in the egg, compared to most birds' one-and-a-half to four weeks—whereas the keratin sheath on a beak is much faster. (Though beaks are also lighter—mercifully I don't have to recalculate my dragons' mass—but that doesn't explain why ground-bound dinosaurs sometimes developed them.)