> An earth-like planet orbiting a different star would likely have evolved photoreceptor arrangements which match that star instead.
No, not really- the limitation is chemical, not evolutionarily-driven. Earth is very well lit in infrared, but it's very difficult to make a chemical that is biologically useful for seeing infrared because the wavelengths are just too long. Its very challenging to do more than the most primitive kinds of sensing in infrared. If our sun was much dimmer, we would probably be blind, but if not our eyes would still not see in far infrared. Same goes for ultraviolet- the energy is too high and molecular bonds are too weak. Seeing in visible light is a reversible reaction, but ultraviolet wouldn't be.
What you're saying is true of ocean animals, especially in the deep sea. They don't see red very well or at all, but the evolutionary pressure against seeing red is not terribly high except very deep where food is very limited.
There also is evolutionary pressure on our vision, but it has nothing to do with the sun. We're twice as sensitive to green since it is so common and important, but green comes from photosynthesis and not from the color of the sun. In a way, we are most sensitive to the least important color of light- the color that is not absorbed by plants. The wasted, useless byproduct of sunlight is what lets us identify food.
Plus, we actually basically only see in blue and green. The overlap between rods and red/green cones is huge. "red" and "green" as we perceive them are mostly fabrications of our neural circuits- if we were seeing them how our photoreceptors actually receive light, all shades of green/red would be very strongly mixed together. All shades of red would look significantly green except for the very farthest reds, which would look very dark because of low sensitivity.
> From what I've heard from auto engineers I know, using the battery as part of the structure is not really done. Transfering mechanical stresses to the battery is something you just do not do.
This is technically true, but structural batteries are not the same as stressed engines like on a motorcycle. In the latter, the engine fully replaces a frame member with essentially just the engine block. With structural batteries the cells themselves are not taking on any stress (they could, but yeah its not a very safe idea) but the outside containment is stil doing double duty. Its a pretty minor weight savings because the battery case does not need to be as strong as the frame does, but its not fair to say that structural batteries are not done. Even when they are just bolting on to a subframe, they're still usually doing things for frame stiffness.
The problem is people are conditioned so hard on the "drive till empty then fill up" method of car ownership, that it's totally incomprehensible to imagine not being able to put 300 miles in your car in 5 minutes.
Topping off everyday at home just doesn't register. Driving 7 hours with only one 30 minute charge doesn't register.
It either needs to function like a gas car, or it's not even worth considering.
There are millions of people living in cities that do not own their own home, that cannot charge every day (speaking as an EV enthusiast that rents somewhere that thankfully has public charging across the street). For those that are able to charge at home, there is definitely a mindset shift that needs to happen. I have seen the lightbulb over my friends heads turn on when I ask them how they would like it if their gas cars could fill up 1 gallon per hour at their house, and if so why would they care how long a gas station fill up takes.
The earth is actually a pretty big heat source in space. Solar radiation is a point source, so you can orient parallel to the rays and avoid it. The earth takes up about half the sky and is unavoidable. The earth also radiates infrared, the same as your radiators, so you can't reflect it. Solar light is in the visible spectrum so you can paint your radiators to be reflective in visible wavelengths but emissive in infrared.
Low satellites are still cooler in the Earth's shadow than they would be in unshadowed orbits, but higher orbits are cooler than either. Not where you'd want to put millions of datacenters though.
The people of Minneapolis are defending their right to accept foreigners into their community. Do you genuinely think those people are being paid? That all those protestors don't genuinely feel that way? That the majority in that state don't, as the polls say, want those people there?
If you really think that people in Texas and Florida have the right to say who gets to live in Minnesota, why?
I think most people would agree that the country has a right to enforce its border integrity -- after all, that's sort of a prerequisite for being a sovereign nation.
But not with an unaccountable, unidentifiable, largely-untrained, and "absolutely immune" paramilitary police force, forcibly deployed in cities that don't want them there. Cities that are, in any event, nowhere near any borders.
This isn't really about immigration enforcement. If it were, then what ICE was doing under Biden was more effective than what Trump is doing now, just going by the numbers. There is a widespread conspiracy theory, to which I wholeheartedly subscribe, that maintains that Trump is deliberately trying to provoke circumstances that will justify his use of the Insurrection Act or other quasi-legal shenanigans to ratfuck the midterm elections.
The people of Florida and Texas do not have the right to say who gets to live in Minnesota, but neither do the people of Minnesota. The federal government has sole authority over immigration (but not to murder people while enforcing, obviously). The alternative is ridiculous and incompatible with freedom of movement within the country.
> skewing their biases in a way that creates internal chaos and dissent, disrupting institutional order, and sewing distrust of thy neighbor.
I don't really have respect for this idea; we do this to ourselves far more effectively than people who frankly have a pretty hamfisted cultural understanding- just as we have of china or russia.
IMO influence over real concrete choices is much more alarming. Someone with household-level information has an insane amount of advantage in an election. You can target politcal messaging street by street to play up the worst aspects of your opposed candidate and the least repulsive aspects of your own candidate.
But if you're in china, the most you can do is try to push towards whatever of the two candidates is least bad for you. And spoiler, zero american politicians are pro-china.
This is the difficulty with propaganda- you have to tailor it to a foreign audience but then the message is changed.
America has been trying to spread it's way of life for a hundred years. People liked the fridges and cars but never cared much for the Christianity and croony capitalism.
> And spoiler, zero american politicians are pro-china.
..Other than, well possibly, Trump. Maybe not directly, but the Tiktok deal, withdrawing from the TPP, the eventual outcome of the trade war, the praise for Xi—all stands to benefit China at the expense of the US.
> I don't really have respect for this idea; we do this to ourselves far more effectively than people who frankly have a pretty hamfisted cultural understanding- just as we have of china or russia.
Idk that there's much of a privacy sell vs. messages being encrypted. In the end users are just trusting Apple to actually be securing messages; they aren't going to love that they are trusting dozens of strangers instead of telecoms. Plus, police etc. already snoop on phones by spoofing cell tower relays anyway.
> Showcasing it's use on a cruise ship, in a packed stadium
Stadiums will still max out the pipe out of the local area, so I suspect it wouldn't help much. Festivals and cruise ships, where you want to reach people who are nearby (and at a festival, you might even have a good idea via gps which peers are better) are in desperate need of this and idk why apple didnt solve it years ago.
Axial flux motors are difficult and expensive to make.
Motors need to be made of laminated steel sheets to reduce parasitic eddy currents. The laminations need to be thin in the direction of the direction of the flux. For radial flux motors you just punch out a shape and stack a bunch of sheets up. For axial flux you have to wind a strip: https://15658757.s21i.faiusr.com/2/ABUIABACGAAgmviFqAYozvPw-...
Each layer of that strip has a different cut in it, so its much more complicated to make. The shape and manufacturing method typically impacts efficiency; YASA avoids that by spending more money. Efficiency is an unavoidable requirement of high power density- heat is the limiting factor, and going from 98% to 96% efficient means double the heat.
The mechanical demands on the motor are also much higher- radial flux is balanced since the magnetic force pulls the rotor from opposite sides. Axial flux motors are usually one-sided, so the magnets are trying to pull the rotor and stator together with incredible force. That also makes vibrations worse. Extremely strong, expensive bearings are required to handle it. With permanent magnet rotors you need a jig to lower the rotor into place; they can't be assembled by hand. That also makes maintenance more difficult and expensive.
>> Each layer of that strip has a different cut in it, so its much more complicated to make.
You can roll a spool of that material and then machine the shape out of it. I've seen this done for axial flux motors. There are other approaches as well, and the cost differences get even smaller if you throw automation at the production process. I used to believe axial flux motors were one of those oddities that won't win in the end, but now that I work with them I'm not so sure. They are at least competitive with radial flux machines.
Can you (or anyone) explain where the power density improvement comes from with axial flux? When I work through the first-order math it seems like it should come out the same as radial flux. Is it just that the geometry allows better cooling from the coils? Or the use of grain oriented steel?
Its freshwater and has to be freshwater because it goes through pipes and/or is evaporated. Corrosion, scaling and fouling are all issues.
Even if seawater was easy to use and datacenters were near the shore, it would produce very saline brine which would be difficult to safely get rid of.
No, not really- the limitation is chemical, not evolutionarily-driven. Earth is very well lit in infrared, but it's very difficult to make a chemical that is biologically useful for seeing infrared because the wavelengths are just too long. Its very challenging to do more than the most primitive kinds of sensing in infrared. If our sun was much dimmer, we would probably be blind, but if not our eyes would still not see in far infrared. Same goes for ultraviolet- the energy is too high and molecular bonds are too weak. Seeing in visible light is a reversible reaction, but ultraviolet wouldn't be.
What you're saying is true of ocean animals, especially in the deep sea. They don't see red very well or at all, but the evolutionary pressure against seeing red is not terribly high except very deep where food is very limited.
There also is evolutionary pressure on our vision, but it has nothing to do with the sun. We're twice as sensitive to green since it is so common and important, but green comes from photosynthesis and not from the color of the sun. In a way, we are most sensitive to the least important color of light- the color that is not absorbed by plants. The wasted, useless byproduct of sunlight is what lets us identify food.
Plus, we actually basically only see in blue and green. The overlap between rods and red/green cones is huge. "red" and "green" as we perceive them are mostly fabrications of our neural circuits- if we were seeing them how our photoreceptors actually receive light, all shades of green/red would be very strongly mixed together. All shades of red would look significantly green except for the very farthest reds, which would look very dark because of low sensitivity.
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