You talk like there's only one fusion project. Plenty of projects do a lot more than one shot a day. Helion does way more.

Get up to speed on what's actually happening in the field before you write it off so confidently.

"Period." I looked up the name of the missing little dot at the end :)

He has a ton of great videos, and there's a subreddit. (And thanks for teaching me a word :)

For the orbital ring? Not geostationary. Lots of little rings, say 10 meters wide, with attached solar panels, hanging stationary just 150 miles up, cabled to the ground. They're held up there by the momentum of the iron chunks, circling the earth at faster than orbital speed, each one deflected by the electromagnets of each little ring so it doesn't shoot out to a higher orbit.

Here's a video but that's a more advanced version that's actually solid all the way around the ring.

Spider silk is really strong but not as strong as the nanotube cable would be, and not quite strong enough for a space elevator.

With the orbital ring, you only go, say, 150 miles up. You have a ring in any circular orbit around the planet. This ring does not have to be solid; the key is a bunch of hunks of iron, moving at faster than orbital speed. Those are electromagnetically deflected by passing through rings, which are cabled to the ground. The deflection pulls the rings upwards.

Getting to 150 miles altitude is just like a space elevator. After that, you use the momentum of the orbiting metal to launch you to orbital speed. You have to keep accelerating the metal chunks, so you need a bunch of solar panels.

All this can be done with today's technology for a few billion dollars in launch cost, you'd effectively get lots of space elevators instead of just one, and it could get payloads to orbit for $0.05/kg. But you'd need all the countries along a great-circle path around the planet to work together on it.

Before doing all that though we could do a launch loop, same basic idea but it's just a couple thousand miles long, and instead of the metal orbiting the planet it travels in an arc and back along the ground.

Imagine everyone living for 250 years. Personally I'm not willing to sacrifice an extra 150 years of life just to kill a few billionaires.

Society would not collapse. Anti-aging could actually save us from an upcoming demographic crash. As populations urbanize, birth rates go down, and most advanced nations are way below replacement rates.

Meanwhile, between cheap solar, probably fusion (see my other reply), and cultured food production, our per-capita impact on the planet could well shrink by a lot over the next fifty years.

We don't have a cable that can reach to geostationary without breaking under its own weight. It's theoretically possible with nanotubes, but we'd need to mass-produce 7cm nanotubes, line them all up parallel and glue them together, and we're not there yet.

We do have cables that could get to LEO, which would let us build an orbital ring. That'd arguably be even better than an elevator, but it'd take more coordination between countries.

At this point fusion is probably more like ten years in the future.

Fusion progressed exponentially from 1970 to 2000, at a faster pace than Moore's Law. Then 35 nations threw almost all their fusion money at ITER, a giant reactor in France that won't actually run before 2027, and hopes to attempt fusion in 2035.

But technology moved on. We have new superconductors that let us build a reactor like ITER but ten times smaller, and several companies are doing it. We have supercomputers that are way better at plasma simulations, letting us design new types of fusion reactors that are smaller and cheaper. Lasers have advanced exponentially too; the NIF project technically got net power from fusion last year, but used giant lasers that are less than 1% efficient; we have lasers now that can do the same thing, but they fit in a small room, are over 20% efficient, and can fire once a second instead of twice a day. We have way better power electronics.

Startup companies are taking advantage of all of this. Zap Energy is attempting net power this year, CFS in 2025, General Fusion in 2026, and Helion is attempting overall net electricity in 2024 with a mostly-aneutronic fuel.

Flying cars are more practical than you think. Read the book Where Is My Flying Car?

General aviation, i.e. small private planes, used to be a much bigger thing than now. Back in the 1970s there were about ten times as many Cessnas and similar planes flying, and about that many more small runways. It was working out fine, and then the FAA threw such a heavy load of regulation on top of the industry that it collapsed.

Among other things it became really difficult to develop new aircraft and get them approved. This did not improve safety; it worsened it, as people had to rely on old technology.

Contrary to common fear-mongering, people with pilot licenses are perfectly capable of flying small aircraft without crashing everywhere, and many "flying car" designs are easier to fly. Decades ago we still would have needed serious training, but today, automating a flying car is way easier than automating a ground car, and we already have computer-controlled flying drones.

The big advantage of flying cars is speed. The book argues that you get a big jump in economic productivity when an average person can travel further in an hour. With flying cars, that one-hour range could be several hundred miles.

Generally what people mean by flying cars is VTOL, so you don't need to build runways for them. Of course there's helicopters, but they're expensive and noisy and helipads are still pretty big.

Automation is pretty easy for flying. We already complete automation for flying drones.

And if you don't read the full article, you don't get the point of the article, which also said Dyson spheres are easily worthwhile if they're a meter thick with partial coverage. That's probably not a terrible approximation of a Dyson swarm.

Right, the article compares the energy cost of disassembling planets to the energy that could be collected by the Dyson sphere you could build from the materials.

In fairness the article also talks about meter-thick solar panels, and concludes that it's easily worth it that way. And in most scenarios it's talking about partial coverage.

A meter seems like a reasonably fair estimate, if you include things like power transmission equipment, factories and spaceships for replacing panels, etc. Doesn't matter if you can go even thinner, since a meter thick already works great.

The expensive part isn't the people, it's the mountain of GPU required to train the AI.

You don't need conscious awareness to beat me in chess, and maybe you don't need it to beat all of us and take everything.

So what worries me is not that we're copyable, but that maybe we're not. We can't prove whether another person or an animal actually experiences qualia. What if the machine doesn't, but wipes out all life anyway? Then the light of consciousness would go out of the world.

They're building a factory that's supposed to produce 5 GWh/year, hopefully that will help with the cost. Still nowhere near Tesla Gigafactory levels but it's a start.

They say it plugs into normal battery production lines, I'm wondering if Tesla could license it and adapt their factories.

25C would be incredible but it's still good enough for aviation and cars. I think I saw 10C.

Depends, if they start mining then they could easily need a megawatt or two. Which is probably why Rolls-Royce is including that size in their designs.

If each of those EV batteries is a 100 kilowatt-hour Tesla battery, and your lunar base uses just one kilowatt like an average American house, then sure, three batteries will last for (almost) two weeks since there are 336 hours in two weeks.

But Rolls-Royce is talking about a reactor that can provide megawatts. If we need a megawatt of power instead of a kilowatt, then we multiply our battery requirement by a factor of a thousand.

Check out the blog by Vitalik Buterin, the founder of the second-largest blockchain. All sorts of interesting stuff in there.

> we would need more energy than the energy previously hold in all that burnt fossil fuel

That would be necessary if we had to split all the CO2 into carbon and oxygen. But we don't have to do that; we can inject the CO2 into deep basalt formations, where it will turn into rock.

So we just have the energy cost of concentrating the CO2 from the air and pumping it underground, which is a lot less.

They basically say we're the ones who lowered the iron level. You don't think that might go wrong?

Yes, but people in business tend to get a lot of emails, and if most of them resort to text summarization then the nuance is lost anyway. And it's mostly lost if the recipient skims.

Also, many senders of email aren't necessarily great communicators conveying valuable nuance anyway.

Ultimately, it's a cost-benefit calculation: get occasionally-valuable nuance on a bunch of emails, or keep emails simple and do something else that might be more valuable?

People in businesses will write out some bullet points and an AI will expand them into essays.

On the other end, people without the time to read much will have an AI summarize those essays in bullet points.

After a half century or so, everyone will get it through their thick heads that this is stupidly inefficient and just exchange the bullet points.

Eventually, population will start rising again if the anti-aging tech is good enough. But in that eventual higher-tech future we might also have cheap fusion, cheap space travel, and really compact food synthesis, so we'll be able to support much larger populations. We're making progress towards all of these things.