The GP was just setting a lower bound of 1B to establish a basis for calculating the cost to move humanity offworld. The cost for 5B people or 7B people would be even more cost prohibitive.
But also the shrinkage would not have to happen abruptly. In theory you might be able to get to a population of 1B over the course of 200 years without the kind of catastrophic meltdown you're describing.
I completely agree this would happen over a long time, barring a disaster like nukes or asteroids, which does not seem like the most credible scenario (I dont think I said anything to the contrary)- and I'll confess to a pessimistic vision of the future, when our demise is self inflicted.
But look at Covid for a reference point. I mean all things considered this was still too mild to reduce humanity to 1B. This almost immediately (in the span of a year) led to big issues with the supply chain. Products removed from the shelves, years long backlogs on cars. People getting sick all around you and hospitalized, and yet there were societal debates on whether the disease actually existed, whether we should wear masks, or take the vaccine. Climate change is in the same line, people denying change with snarky remarks every time we receive a snowflake, and any step forward being accompanied by two steps backwards (look at the Paris accords). What I mean there is that there is no change witnessed without actual pain, and the change required for something truly threatening for humankind (e.g climate) won't see any actual action till we're already greatly suffering, and probably beyond the point of repair.
Now imagine a large chunk of the population disappearing, even over the course of decades, and whether that would leave society in a state where it can afford a significant "gtfo of here" space program. My personal opinion, and that is only an opinion, is that this is not systemically possible ; and therefore I don't believe in GP's base assumption, even if that's departing from the motivation of simplifying that they made :)
In any case, beyond cost, short of inventing completely new physics, I doubt earth even has enough resources to catapult us all into and then out of orbit.
The most likely scenario to me is a handful of elites (which fortunately for them are fewer and fewer) embarking on rockets, accompanied with scientists and engineers to give them a fighting chance, plus a bunch of slaves to do the grunt work and die, because surviving ain't worth it if you can't enjoy life.
(once again, I confess is a pessimistic vision, and is also departing a bit from the initial statement from GP)
planet is an amalgam of rocks and minerals, heat is provided by the sun, water could have been of extraterrestrial origin, and then enters fungi using heat and humidity to develop mycelium, mycelium turns minerals into compost with enzymes, space dust introduces bacteria which evolves through thermal vents a/biogenesis, and voila, you have life. We do know that before vegetation, Earth had fungi structures made of half rock, half fungi flesh, and they probably evolved into actual trees. At the same time, lichen spread from underwater to the surface of the Earth. Fungi released CO2, creating an atmosphere for plants to develop. The rest is evolution.
I think it's at least strongly implied in the movie that he has to work much harder than (for example) his genetically superior brother to achieve the same level of performance. So maybe you're both right.
From the point of view of the Space Agency even though his ‘spot’ performance meets the grade he’s still an unacceptable risk as an astronaut - he might die during a mission potentially harming others - and if so all the resources spent on that mission and training would have been wasted.
In a sense it’s the external political struggle of whether a society allocates resources to everyone to maximise their personal potential, or focuses resources on a subset of talented individuals likely to give the best overall return.
I think you're both right. Introducing H2 as a fuel only helps matters if the energy used to produce the H2 is not from fossil fuels, and probably hurts otherwise.
Right now the world produces a small fraction of its electricity cleanly and the rest using fossil fuels. If you want to divert some of that human energy consumption from heating/cooling/cooking/lighting/computing to H2 production then how do you make sure the diverted energy is from clean sources and that those consumers don't take it upon themselves to fill the new hole in their lives with additional fossil consumption?
If you're going to say we should create petawatt-hours-per-year of additional electricity generation capacity in order to do this, that sounds great but the infrastructure doesn't exist and it will take decades-to-centuries to build it.
So, I'm very much in favor of developing and maintaining the technological expertise required to use H2 for energy. I'm not nearly as convinced when it comes to trying to deploy it at scale in the 2020s.
> I think you're both right. Introducing H2 as a fuel only helps matters if the energy used to produce the H2 is not from fossil fuels, and probably hurts otherwise.
That's "green hydrogen" by definition - ie. what this article & discussion is all about. The gp is simply mistaken, and the coal analogy is ridiculous. Whether green hydro turns out to be economic/scalable is a separate matter.
I don't know what this LOHC stuff really is, but it's easy to imagine that dissolving H2 in in an existing liquid would be much less of an undertaking than inducing it to become C8H18 or whatever.
OS kernels tend to use them simply because they don't have malloc at their disposal and so it's most practical to stick to fixed size memory chunks, right?
Linux kernel's malloc is probably more resilient to the long-term (as in, long running) problems you would get from continually resizing an array with realloc in userspace (ie. massive heap fragmentation and eventually dying in flames)
I'm glad you linked to that article, which I had not seen before.
I think I agree with the author about degrowth as a goal being a political nonstarter. But I'm pretty skeptical about the notion that future growth can consist of ever increasing amounts of "dematerialized" goods and services without ceasing to be real, meaningful growth (however it might be defined).
I also think the political and physical challenges inherent in technological or "pro-growth" (I need a better word) solutions for getting out of overshoot are widely underappreciated. This [1] article runs some numbers to show that, for our global civilization to satisfy its current level of energy consumption without emitting significant amounts of greenhouse gases in 2050, we will have to bring online clean energy generation capacity equivalent to one nuclear power station every day between now and then. Given that, I'd be extremely surprised to see us get there by 2150, or maybe at all.
But also the shrinkage would not have to happen abruptly. In theory you might be able to get to a population of 1B over the course of 200 years without the kind of catastrophic meltdown you're describing.