Category: Science, Nature, & Technology

Source: No politics please, we’re hackers, too busy to improve the world · Jacques Mattheij

If there is one thing that never ceases to amaze me it is that the hacker community tends to place itself outside and by their own perception above politics.

What bugs me about this is that anything you make or do has a political dimension, and that hackers, more than any other profession, create the tools and the means with which vast changes in the political landscape are effected. It’s as if arms dealers and manufacturers refuse to talk about war, the ultimate consequence of the tools they create in the environment where they will be used.

Both from an ethical viewpoint as well as from one related to personal responsibility this is simply wrong. The ability to influence with disproportional effect on the outcome of all kinds of political affairs compared to someone not active in IT, the ability to reach large numbers of people, the ability to pull on very long levers, far longer than you’d normally be able to achieve comes with some obligations.

Hackers, computer programmers and associated groups can not afford this Ostrich mentality

As soon as you and your software hit the real world politics will rear its ugly head. … everything has a political dimension and sometimes that political dimension can overshadow all other aspects of the project. This translates into an obligation to engage the political angle of whatever it is that we collectively produce in order to minimize feelings of regret later on and to really help to make the world a better place, rather than just to pay lipservice to that concept.

Long touted as the “perfect” energy source, fusion reactors share many drawbacks with fission—and even add a few new ones of their own.

tl;dr:

• Terrestrial fusion reactors need to use tritium (neutron-rich hydrogen isotope) as fuel.
• Tritium fuel can only be acquired from fusion and fission reactors, and it cannot be fully replenished from the fusion reactor itself.
• The power required for a power plant to operate itself is called “parasitic power drain”. Fusion reactors require an enormous amount of power to operate and this parasitic power drain forces fusion reactors be very large in order to be economical. Furthermore, 75 to 100 megawatts of parasitic electric power is used (e.g. for refrigerators) even when the fusion reactor is off (e.g. for maintenance).
• Deuterium-tritium reactions’ fusion energy output is 80 percent energetic neutron streams (deuterium-deuterium is 35 percent), not usable electricity or heat. These streams lead to radiation damage to structures, radioactive waste, the need for biological shielding, and the potential for the production of weapons-grade plutonium 239.
• Neutron streams must be cooled to produce usable heat, but this incurs radiation damage to the reaction vessel (swelling and fracturing) and everything that it irradiates (e.g. coolant, the vessel, fuel assemblies,
  non-structural components) will become radioactive waste over time.

• production of plutonium 239 is possible in a fusion reactor simply by placing natural or depleted uranium oxide at any location where neutrons of any energy are flying about. The ocean of slowing-down neutrons that results from scattering of the streaming fusion neutrons on the reaction vessel permeates every nook and cranny of the reactor interior, including appendages to the reaction vessel. Slower neutrons will be readily soaked up by uranium 238, whose cross section for neutron absorption increases with decreasing neutron energy.

• Tritium handling is hard and tritium is environmentally hazardous.
• Deuterium and tritium are themselves usable as boosting/supplemental components to nuclear weapons.

• a fusion reactor would have the lowest water efficiency of any type of thermal power plant, whether fossil or nuclear.

To sum up, fusion reactors face some unique problems: a lack of natural fuel supply (tritium), and large and irreducible electrical energy drains to offset. Because 80 percent of the energy in any reactor fueled by deuterium and tritium appears in the form of neutron streams, it is inescapable that such reactors share many of the drawbacks of fission reactors—including the production of large masses of radioactive waste and serious radiation damage to reactor components. These problems are endemic to any type of fusion reactor fueled with deuterium-tritium, so abandoning tokamaks for some other confinement concept can provide no relief.

Source: Fusion reactors: Not what they’re cracked up to be | Bulletin of the Atomic Scientists by Daniel Jassby

There’s a list of scientific mavericks who were ridiculed by hidebound reactionaries but later vindicated that’s been going viral. … my impression is that only a third of these people really fit the pattern. Most of them were doubted for very short periods, continued to be respected in their fields for their other accomplishments even during those periods, or were part of medium-sized movements rather than being lone geniuses. After a few years – maybe an average of ten, very rarely as long as thirty – their contributions were recognized and they assumed their rightful place in the pantheon. Science isn’t perfect. But it is darned good.

I’ve always thought something like:

Scientific consensus is the best tool we have for seeking truth. It’s not perfect, and it’s frequently overturned by later scientists, but this is usually – albeit not literally always – the work of well-credentialed insiders, operating pretty quickly after the evidence that should overturn it becomes available. Any individual should be very doubtful of their ability to beat it, while not being so doubtful that nobody ever improves it and science can never progress.

– and I still think that. But I’ve shifted from being the sort of person who shares viral lists of maligned geniuses, to the sort of person who debunks those lists. I’ve started emphasizing the “best tool we have” part of the sentence, and whispering the “isn’t perfect” part, rather than vice versa.

I knew some criticisms of a scientific paradigm. They seemed right. I concluded that scientists weren’t very smart and maybe I was smarter. I should have concluded that some cutting-edge scientists were making good criticisms of an old paradigm. I can still flatter myself by saying that it’s no small achievement to recognize a new paradigm early and bet on the winning horse. But the pattern I was seeing was part of the process of science, not a condemnation of it.

Most people understand this intuitively about past paradigm shifts. When a creationist says that we can’t trust science because it used to believe in phlogiston and now it believes in combustion, we correctly respond that this is exactly why we can trust science. But this lesson doesn’t always generalize when you’re in the middle of a paradigm shift right now and having trouble seeing the other side.

where this fails is not in the experts but in the ability of people who don’t listen to the experts to get disproportionate social power and hide the existence of the expert consensus.

Scientific consensus hasn’t just been accurate, it’s been unreasonably accurate. … The idea that scientific consensus is almost always an accurate reflection of the best knowledge we have at the time seems even more flabbergasting than any particular idea that scientists might or might not believe. But it seems to be true.

Source: Learning To Love Scientific Consensus | Slate Star Codex

Related to: Contrarians, Crackpots, and Consensus, How Common Are Science Failures?

Few people appreciate what it’d mean to take our climate goals seriously.

To hit the Paris climate goals without geoengineering, the world has to do three broad (and incredibly ambitious) things:

1) Global CO2 emissions from energy and industry have to fall in half each decade. That is, in the 2020s, the world cuts emissions in half. Then we do it again in the 2030s. Then we do it again in the 2040s.

2) Net emissions from land use — i.e., from agriculture and deforestation — have to fall steadily to zero by 2050. This would need to happen even as the world population grows and we’re feeding ever more people.

3) Technologies to suck carbon dioxide out of the atmosphere have to start scaling up massively, until we’re artificially pulling 5 gigatons of CO2 per year out of the atmosphere by 2050 — nearly double what all the world’s trees and soils already do.

2020-2030: … carbon pricing would expand to cover most aspects of the global economy, averaging around $50 per ton and rising. Coal power is phased out in rich countries by the end of the decade and is declining sharply elsewhere. … Wealthy countries no longer sell new combustion engine cars by 2030, and transportation gets widely electrified, with many short-haul flights replaced by rail. … In addition, spending on clean energy research increases by “an order of magnitude” this decade … By 2030, we’d need to be removing 100 to 500 megatons of CO2 each year and have a sense of how to scale up.

None of this is easy. It might well prove impossible. But this is roughly what staying well below 2°C entails

Source: Scientists made a detailed “roadmap” for meeting the Paris climate goals. It’s eye-opening. – Vox

Programmers talk about technical debt: there are ways to write software that are faster in the short run but problematic in the long run. Managers talk about institutional debt: institutions can grow quickly at the cost of bad practices creeping in. Both are easy to accumulate but hard to get rid of. Research can also have debt.

The insidious thing about research debt is that it’s normal. Everyone takes it for granted, and doesn’t realize that things could be different.

Source: Research Debt