Category Archives: Web Article Review

Where are the Small Modular Reactors?

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Small modular nuclear reactors might be a key part of the solution to the climate crisis, or they might not. They seem to be near the end of the R&D stage (although doubtless they can and will continue to be improved) and at the very beginning of pilot testing/proof of concept. They are not yet economically competitive with other forms of power generation (including traditional large nuclear reactors), which you could say about pretty much any new technology. There is a chicken and egg problem where you have to implement it and scale it up for the unit price to come down, and it is hard to get the private sector (and public sector, if they are short-term financial return focused) to take the chance on implementation of something that might end up not working out. Of course, the idea is to invest in a portfolio of things that have some chance of working out, such that there is a high chance at least one of them will pay off. Anyway, some facts and figures in this Physicsworld article (isn’t that name slightly redundant?):

  • Nuclear power generated 17.5% of the world’s electricity in 1996, vs. only 9% today (2026 if you are a future historian reading this).
  • I somewhat naively thought US firms might be leaders in this technological knowledge (if not in implementation of anything at scale, where I would never be that naive). But it turns out that there are two of these reactors currently operating in the world, and they are in Russia. Two are being built in China.

Sure, there are mining, supply chain and waste problems, but in my view you have to balance them against the unfolding global ecological catastrophe caused by burning fossil fuels for two centuries and counting.

WEF Global Risks Outlook 2026

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I think of this thing as not so much a prediction but an indicator of what political and business leaders are thinking and talking to each other about. The results seem to be very sensitive to whether people are asked about a 1-, 2-, or 10-year horizon. So I don’t know that the rankings make a lot of difference. Rather, it makes sense to look at a “top 10” or so. Chillingly, more than half of poll respondents seem to think there is an “elevated” to “looming” risk of “GLOBAL CATASTROPHE” within the next 2-10 years. Within 2 years, they are most worried about “geoeconomic confrontation” while within 10 years they identify environmental disaster as the top 3 worries – “extreme weather events”, “biodiversity loss and ecosystem collapse”, and “critical change to earth systems”. “State-based armed conflict” (would it be simpler to just call this WAR?) is also up there somewhere near the top. “Inequality” doesn’t rank as high, but the analysts identify it as the risk that is most “interconnected” with the others.

How pathetic for our species and civilization that our leaders believe environmental disaster is looming a decade out, and yet they are starting wars with one another on our behalf in the present, when they know damn well they need to be cooperating to head off the environmental disaster that is going to affect all of us, the winners and losers of today’s useless wars alike. People don’t want war, so how are we putting people in leadership positions over us who are failing us so utterly?

https://www.weforum.org/publications/global-risks-report-2026/infographics-global-risks-report-2026/
https://www.weforum.org/publications/global-risks-report-2026/infographics-global-risks-report-2026/

what to eat, or you can take my cheese…WHEN YOU PRY IT FROM MY COLD DEAD HANDS!

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Harvard School of Public Health explains how the new U.S. government nutrition guidelines were developed without proper scientific oversight. The normal process is a transparent one where an expert panel reviews the latest evidence and submits a report with recommendations, supposedly without any bias or industry influence. (A cynic could probably look at these highly credentialed experts at leading universities and show that they receive research funding from industry and from government agencies being heavily lobbied by industry, because where else would they receive funding from? But they can at least channel any propaganda through some scientific and ethical guardrails you would hope.) USDA employees aren’t obligated to follow these recommendations to the letter, but they at least give them some weight and balance them against the economic and political factors. This time the panel submitted their report as usual, but USDA then cherry-picked a separate set of experts to produce a “supplemental report” without the transparency or adequate documentation. And the guidelines are then based on that. So they are not credible.

Even though the process was not credible, the consensus seems to be that the new guidelines are not really all that different. The main issues have to do with how they are being (badly) communicated, including an apparent emphasis on more saturated fat (which is not really what the technical guidelines say at all, but the concern is that very few people will drill into the technical guidelines). If I can try to clarify the saturated fat issue, it seems to be that a portion of the population that has no cholesterol issues may be able to increase saturated fat intake with no ill effects, but a portion of the population that has cholesterol issues will have more heart attacks and strokes and early death if they do so. Nutrition advice really should be more personal in an ideal world, but with public health guidelines, broad, simple, clear statements that benefit a majority of the public on balance seem to be the way to go. And replacing saturated fat with healthier plant-based fats and oils definitely seems to fall in this category. If people who are eating a lot of sugar and processed garbage were to replace it with meat, that might actually benefit them which may be what the guidelines are trying to say. Of course, they should be replacing it with fruits, vegetables, beans, nuts, seeds, whole grains, healthy fats and proteins. And I want to state that I support vegetarians and vegetarianism on ethical and environmental grounds. These considerations are missing entirely from the government’s concept of “nutrition”, and they should not be.

Another criticism I have always had of these guidelines is the use of weight, like eat so many grams of fat per day, or fat should be X% of your calories. Even those of us who might consider ourselves reasonably quantitative and logical think in volume or area, not weight. If you told me to aim for X tbsp of vegetable oil per day or Y slices of cheese, I could do that. Tell me Z grams or ounces, and I have no idea what to do, and then I am supposed to convert that to energy units (calories) and determine what percentage it is of my total calories for the day. But people don’t pay much attention to these guidelines anyway. They need to be getting this information from “trusted messengers” like teachers and doctors, and if these messengers had simple clear messages from the government that they themselves understood and trusted, they could just pass them along. Something like a point system that approximates the weights and calories involved could work.

I don’t think these guidelines have much short-term impact just because us laypeople don’t pay attention, and the professionals that could help us eat better don’t get clear communication materials out of these guidelines that they can work with.

But the longer-term damage here is the damage to the credibility of government health and medical advice. When I tell my kids “not to believe everything you hear and read on the internet”, I tell them to be aware of the source of the information. And one source I would have considered credible in the past is a major federal agency like USDA, CDC, etc. If major government, academic, and professional journalistic sources are telling you the same thing and it matches what that social media influencer or your friend are telling you, it’s still not 100% guaranteed to be true but you can start to have some confidence. But the credibility of federal agencies has really been significantly damaged by this administration and it may take a long time to recover, even if the past norms are ever put back into place.

my “top 10 U.S. political/geopolitical events of the 21st century”

This Silver Bulletin post is called “The 51 biggest American political moments of the 21st century”. I liked it because it made me think. I found that the non-chronological nature of it threw me off a little bit. So I decided to come up with a “top 10 (U.S.) political/geopolitical moments of the 21st century” of my own. I picked some events off Nate Silver’s list, thought of a few extra of my own, and then put them in chronological order. Limiting it to 10 forced me to really think about what was most important, although like Nate I occasionally cheated by putting things together. I leaned towards events that were true “watershed moments” in the sense that they could have gone differently and the outcome for the U.S. and possibly the world might have been very different. I also leaned towards events where I remember where I was or what I was doing at the time, because I suspect those are important. I included 2000 as Nate did.

  • December 12, 2000: Bush v. Gore. I remember literally falling on my knees when CNN “called Florida for Gore” (the floor of my rental apartment in New Jersey was carpeted). Where would we be if this had gone differently? In general, you may see a theme below that I see Democrats as basically protectors of the pro-big-business, pro-low-profile-foreign-wars center-right consensus in the U.S. George W. Bush was on the right edge of this consensus, while Gore likely would have been on the left edge. I suspect 9/11 and the Afghanistan invasion would still have happened exactly as they did, but I don’t think the Iraq invasion would have happened. Who knows if other aspects of the 20-year “war on terror” would have unfolded as they did? We would have seen more action and progress on climate change and more standing up to fossil fuel industry propaganda for sure.
  • September 11, 2001. I was in my office building in Philadelphia. My mother called me on my desk phone (I didn’t yet have a cell phone) and told me what was happening. We turned on a small black and white TV with rabbit ears we had in our conference room at the time and watched the events unfold. The streets filled with panicky people and you couldn’t get on a train or highway for hours. There were rumors of additional planes in the air over Pennsylvania (which turned out to be true), but in the end nothing happened to us in Philadelphia directly. When I finally got back to my apartment in New Jersey, there were highway signs saying all roads to New York were closed.
  • March 20, 2003: Iraq invasion. A weird thing I remember is Dan Rather updates on the invasion during halftime of NCAA basketball tournament games. We aren’t used to mixing sports and serious news like that.
  • September 15, 2008: Lehman Brothers collapse. This is a stand-in for the larger financial crisis, surely one of the most important world events of my life time (I might pick the Berlin Wall as the single most important, but now we are going back to a previous century). The sub-prime mortgage derivative collapse might have been inevitable, but letting a major institution collapse was a key decision by the Bush administration that led to panic. It certainly played a large role in the Obama election. Obama understood that however distasteful, avoiding panic was the single most important thing he had to do, and he did it. I am an Obama fan, as I was a Bill Clinton fan and fan of the first 2-3 years of Joe Biden. He was just an effective keeper of the pro-big-business, pro-low-profile-foreign-wars center-right consensus. All these leaders pushed to accomplish the most incremental progress that was politically possible in their moments without blowing up the system.
  • January 21, 2010: Citizens United decision. No, I don’t remember where I was or what I was doing. I probably wasn’t even aware of this in real time. But this was crucial and the U.S. and maybe the world could be different without it. Maybe a marginally less corrupt election system would have delivered different results in 2016, and climate change and health care among other issues could be on a very different track.
  • October 28, 2016: the “Comey letter”. I picked this to represent the catastrophe of the 2016 election (which took place on November 8, 2016). The situation was on a knife edge, and without this “October surprise”, which turned out to be a complete hoax, maybe history would have unfolded differently.
  • November 4, 2016: Paris climate change accord takes effect. Obama really pushed and deserves a share of credit for getting this one done. It could still be in effect if Hillary Clinton or Bernie Sanders had won the 2016 election, OR if the U.S. Congress ever did its job of considering and ratifying treaties. Because none of these things happened, the U.S. never gained any momentum on climate action, and generations of our descendants are going to suffer as a result.
  • Friday, March 13, 2020: Covid shutdown. I picked this date because it is the date the Philadelphia public school system, where my son was in first grade at the time, insisted it would not shut down, and then announced late morning that it would shut down for two weeks, which turned into about a year. It was also the day my employer told me I wouldn’t be coming back to the office on Monday. I picked this date to represent the Covid-19 pandemic as a whole, but I could also have picked the date the first vaccinations were approved by the FDA, which was December 11, 2020.
  • November 30, 2022: Chat-GPT goes public. Not on Nate Silver’s list, but seems important no?
  • June 27, 2024: Biden-Trump debate. Of course, the real watershed moment was whenever Biden and his team decided he would run for re-election. Had he announced sometime in 2023 that he would be walking off gracefully into the sunset and allowing a real primary process to play out in 2024, maybe history and our present moment would be very different.

what’s new with learning curves?

At least since reading some early Singularity-adjacent publications by Vernor Vinge, Ray Kurzweil, and Bill Joy, I’ve been interested in learning curves. (And for the record, the topic and these authors were were not considered politically “right wing” or even political at all at the time.) Progress, at least in certain technologies, tends to be exponential over time. This clearly applies to computer technology, where there are short product cycles, the needed infrastructure is more or less in place and/or can adapt as the technology is scaled/commercialized, and legal and institutional barriers to change are relatively low. Technologies with “recipes”, like chemicals, drugs, seeds and other agricultural technologies, might be other examples. For these we have the patent system to actually try to slow down scaling and commercialization to the pace of innovation. With energy technology, learning curves seem to play out over much longer periods of time because while available technology changes rapidly, our system tends to be locked into long-lived infrastructure that can only change slowly. So new energy technology rolls out slowly as it is scaled up and commercialized over decades. There are also entities with enormous political and propaganda power that fight tooth and nail to keep us locked into obsolete technologies and infrastructure that fit into their historical (and profitable) business models. Now when you get to other technologies, like transportation and housing, public policy, legal and institutional barriers are dominant and tend to retard or even prevent progress. Rollout is so hard that while there are pockets of innovation, many don’t see the light of day or don’t spread from the local/pilot scale, even if they are successful at this scale. These also vary by location and jurisdiction, so that progress is very uneven geographically. These are my thoughts anyway. As for what’s new, here’s a journal article from Advances in Applied Energy.

Variability of technology learning rates

Climate and energy policy analysts and researchers often forecast the cost of low-carbon energy technologies using Wright’s model of technological innovation. The learning rate, i.e., the percentage cost reduction per doubling of cumulative production, is assumed constant in this model. Here, we analyze the relationship between cost and scale of production for 87 technologies in the Performance Curve Database spanning multiple sectors. We find that stepwise changes in learning rates provide a better fit for 58 of these technologies and produce forecasts with equal or significantly lower errors compared to constant learning rates for 36 and 30 technologies, respectively. While costs generally decrease with increasing production, past learning rates are not good predictors of future learning rates. We show that these results affect technological change projections in the short and long term, focusing on three key mitigation technologies: solar photovoltaics, wind power, and lithium-ion batteries. We suggest that investment in early-stage technologies nearing cost-competitiveness, combined with techno-economic analysis and decision-making under uncertainty methods, can help mitigate the impact of uncertainty in projections of future technology cost.

This blog in Construction Physics has a deeper dive across more industries, and discusses at least one large data set that is available for analysis. If you could accurately predict learning rates (and successful scaling/commercialization rates) for specific technologies based on known factors, then theoretically you could fine-tune policies and incentives to increase the rate of progress in the technologies you want. So this is an area of research that could boost all other areas of research and progress.

evidence for the return on (U.S.) government non-defense R&D

This 2024 report from the Dallas Fed provides very clear evidence of the positive returns from past U.S. government research and development funding.

Total factor productivity is a noisy but generally accepted measure of the amount of GDP/productivity growth that is due to innovation rather than increases in inputs. Summary: The return CAUSED BY non-defense R&D spending is 140-210% over 8-12 years, which is higher than investments in infrastructure (which still provide a positive return) and defense R&D (NO CAUSAL EFFECT IDENTIFIED).

Since it’s noisy, maybe I would smooth it in the graph above, but nonetheless there is a very clear relationship between falling R&D spending and falling economic growth. Conversely, if you wanted to intentionally reduce growth and innovation in our economy, a good way to do that would be to reduce R&D spending. Another implication is that if R&D spending on weapons and war does NOT provide as great benefits, there is an opportunity cost to spending your R&D money on weapons and war rather than peaceful or at least dual-use technologies. So it’s pretty clear the actions of the current US administration (drastically cutting R&D spending and shifting it from civilian to military applications) do not match their stated intentions to boost economic growth.

toilet rats, and a Singaporean perspective on Asia at the end of 2025

The two things in my title are only loosely related, and here’s how. The Guardian has a gleeful article about toilet rats in the (US) state of Washington. Indeed, this does seem like a pretty good indicator of US decline. Nonetheless, I have one personal experience with a toilet rat, and it was in Singapore. Older-style public restrooms (confusingly for American tourists, called “toilets” as they are throughout most of the world) sometimes have squat toilets flush with the floor rather than western toilets that you sit on. This is a traditional Asian style of toilet, only the modern squat toilet is collected to a modern sewer system rather than just a hole in the ground. Anyway, I was in the restroom/bathroom/toilet when a rat came out of a little hole in the floor, either not noticing or not caring that I was there. I stamped my foot just to let the rat know that I was by far the larger and dominant mammal in the room, and the rat reacted by diving directly into the toilet and down the drain. And it was gone. So I assume it just swam for a bit until it got somewhere with air, and returned to whatever it was doing after I left. Anyway, the advice in Washington State is if you see a rat in your toilet you are supposed to flush the toilet or close the toilet lid. I would not do either of these things because rats are FAST, they are afraid of people, and they have sharp teeth. I think I would calmly close the bathroom door and just peak in after an hour or two to see if it chose to go back where it came from. And I might keep the toilet lid closed after that.

I have been in actual sewers in the United States, and I have seen rats. Sewer rats are plentiful. They don’t want anything to do with us humans, they just scurry away if they see us coming. I have never seen or heard of one coming into a person’s house through the plumbing. So the article seems a bit alarmist to me. Mice are another story. I just wiped some suspected mouse poop off my kitchen counter this morning, which is gross and a disease risk. Anyway…

The connection between Singapore and rats is that Singapore, which has a reputation as possibly the world’s most sparkling clean very dense city, is not perfect. There is trash and there are rats, like any other city. Singapore, and its experts, have a certain self-endowed swagger. Now Singapore really is pretty clean, and its experts really are pretty smart, which brings me to my point that Singapore is pretty good but not perfect. So anyway, here is what a Singaporean expert, George Yeo, with a lot of credentials says is going on in Asia at the end of 2025. It is one person’s opinion but also a uniquely Asian perspective and different from what we hear from the US government/media/nonprofit “blob”. The article is from Hong Kong-based South China Morning Post by way of Yahoo, so also keep in mind the possibility of censorship and/or self-censorship (as you also certainly should with the US blob).

  • If it ever becomes clear that the US will not continue to support Taiwan, China will take over Taiwan. Taiwan will not fight a war it will obviously lose leading to its own destruction and loss of a generation of its young people. Right now the US and China are sort of avoiding talking about this and trying to actively suppress others (like politicians in Taiwan and Japan) from talking about it, and this is essentially a continuation of the long-term status quo.
  • When we hear about large weapons sales from the US to Taiwan, there is an unspoken arrangement that these weapons are considered defensive and do not cross a certain line. The US is seen to be supporting Taiwan, China is seen to be outraged, and both sides get their propaganda win without serious escalation. Again, it’s the long-term status quo.
  • Another reason weapons will not cross a certain line is that the US will not provide weapons where it has a technological lead. “Knowing that many Taiwanese are blue, the US cannot be sure that advanced technology supplied to Taiwan will not quickly leak into China. The military technology supplied to Taiwan is technology the US can afford to lose to China.” [Wikipedia: “The Pan-Blue Coalition, Pan-Blue force, or Pan-Blue group is a political coalition in the Republic of China (Taiwan) consisting of the Kuomintang (KMT), the People First Party (PFP), the New Party (CNP), the Non-Partisan Solidarity Union (NPSU), and the Young China Party (YCP). The name comes from the party color of the Kuomintang. Regarding the political status of Taiwan, the coalition primarily maintains that the Republic of China instead of the People’s Republic of China is the legitimate government of China. It also favors a Chinese and Taiwanese dual identity over an exclusive Taiwanese identity and backs greater friendly exchange with mainland China, as opposed to the Pan-Green Coalition which opposes Chinese identity in Taiwan.” This also, if I am not mistaken, is the status quo position going back many decades.]
  • “There is growing realisation that the road to independence is a dead end…If the young people of Taiwan build their hopes on an illusion – as the young people in Hong Kong once did – it will only lead to tragedy…Taiwan can enjoy more autonomy by negotiating now rather than waiting another 10 years.”
  • Taiwan has economic and industrial strengths that China would like to maintain and benefit from after a hypothetical reunification [which to me, would seem to discourage any full-out military onslaught on a major urban and industrial city]. This is similar to the situation with Hong Kong, where there is some degree of autonomy and the situation is short of full integration [but in my words – obviously much more limited in terms of political freedom than it was in the past].
  • “How can they ever forget that it was Japan’s aggression which separated Taiwan from the mainland in the first place?” [Interestingly, Taiwanese I know tend to have relatively warm feelings towards Japan. I had to refresh on the history again thanks to Wikipedia – Taiwan was occupied/colonized/ruled by Japan from 1895 to 1945. So it was not invaded and dominated in the 1930s and 40s like much of the rest of China and Southeast Asia, and people there were not mistreated as badly.]
  • On “rare earths” we may hear about the US and its allies developing other sources of rare earths, but there are certain “heavy rare earths” which only China produces, and which are critical to industries around the world. Yeo says China could have played this card at any time in the past, and did so only reluctantly as a bargaining chip in response to the recent round of trade disruptions initiated by the Orange Baboon-Ass God [my words, although he does go into a tangent about the Monkey King which is a Chinese/Buddhist legendary epic. Maybe this is actually a very subtle swipe at his dipshit highness.] Yeo sees this situation as a form of mutually assured destruction where it would be irrational for either side to escalate further.
  • The reality of the US government debt is that if there is a severe contraction or reduction in the growth rate, it would at some point have to print money to service its debt. Central banks around the world are buying gold and diversifying away from the US dollar because of this risk.
  • “He [His Orange-Ass Highness] recognises that the US cannot dominate the world the way it used to in the past. The US hasn’t got the financial power or the manufacturing capability. So it has to retreat some and consolidate around its own core and concentrate on healing itself.” The US knows it is overextended globally, and this is what the bluster over exerting itself in the Western Hemisphere is about. It won’t be able to continue exerting itself globally by sheer power and force, so it is retreating particularly from Asia while still trying to look tough. [Maybe, but aren’t there still the 800+ military bases around the world? And why would we antagonize allies if we are in a position of weakness? I am just saying this is irrational, but I admit that ideology can Trump rationality.]
  • He doesn’t see disputes between China and Vietnam or China and the Philippines in the South China Sea “boiling over”.

construction productivity

Construction Physics has a deep dive on construction productivity around the world. We hear about the overall slowdown in productivity growth worldwide since the 1970s or so, but in the construction industry the trend is essentially stagnation even compared to other industries. The U.S. is a historical leader in absolute productivity but has actually managed a productivity decline compared to modest growth in most other countries studied. That said, there are no countries where the growth is particularly spectacular. Developing countries have managed to grow productivity faster, but that is essentially catching up. It talks a lot about the challenges of measuring productivity, suggesting that just focusing on cost might be the better way to go.

This article doesn’t go deep into potential solutions. Prefabrication of components in factories is talked about a lot, because manufacturing productivity gains have been much more dramatic than construction, which on its face is manufacturing in a much less controlled environment. But prefabrication and modularity have been worked on for a long time and delivered only modest gains. More competition and less corruption in procurement are certainly good things, but these too seem to deliver only modest improvement. Many developed countries in Asia and the Middle East use labor from developing countries, and this seems to work for them but doesn’t deliver large gains I suppose because the lower-wage workers are less skilled and less productive. Streamlining permitting and regulation is always talked about, and tends to fit certain political agendas, but there don’t seem to be enormous gains there. So governments and project teams seem to just pursue an all-of-the-above salad approach and the result is incremental gains or no gains at all. I’ve probably said this multiple times, but I think AI should be very good at construction scheduling. Add in real time inspection and comparison to the original plans using cameras and drones, and it should be possible to really reduce down time and waste in construction. I think there might be substantial potential gains on the horizon here. If I were in government, I might focus R&D funding, targeted procurement, and regulatory/financial incentives on this particular aspect.

Another thought though, is that low construction productivity is not a reason not to do construction. Both housing and infrastructure construction have long-lasting economic and quality of life benefits that go beyond just the immediate economic activity they generate in the construction sector itself. So maybe we should just pony up what they cost now, keep plugging away to try to make the modest gains, and stop worry so much about this.

what’s new with fusion?

One thing that’s new, according to the New York Times, is massive investment in R&D by the government of China. Meanwhile in the U.S., it’s more about startups and public-private partnerships. In at least one anecdotal case mentioned in the article, top scientists from China who have been based at top U.S. universities for decades are choosing to go home. The article suggests that American firms are often the first to achieve breakthroughs, but the Chinese system is better at scaling and commercializing them.

It seems like there is an opportunity to cooperate for the greater good here, no? That is not the way the political winds are blowing at the moment, of course. At least in this case, if our countries aren’t actually cooperating, they are not competing to weaponize the technology first. This technology was weaponized more than half a century ago, of course, and the quest ever since has been to learn how to control it for peaceful purposes. Of course, the joke is always that commercial fusion is two decades away, no matter what decade we are currently in. This article declines to give a clear time table for widespread commercialization, but it talks about a “pilot plant in the 2030s and 2040s”, so yep the rolling two decade projection seems to be holding.

AI investment compared to railway boom

The blog Urbanomics has a comparison of the current AI investment concentration to the 19th century railroad investment boom in England and the United States. In this particular case, the blogger neglected to provide the original source, which he or she normally does. Financial Times and Economist are typical sources. Anyway, here are some stats mentioned:

  • Peak “railway mania” in the UK was around the 1840s, and railroad investment accounted for around half of all investment at that time.
  • Between about 1830 and 1870 in the UK, railroad investment accounted for about 20% of all investment.
  • In the US, episodic railroad investment booms occurred in the 1840s and 1870s. Railroad investment at these times was around 40% of all investment. This accounted for GDP growth of about 6-10%.
  • The brief clip actually doesn’t tell us how much of total US investment in 2025 is directed to AI. But it accounts for GDP growth of around 2%.

These are interesting numbers, but I don’t think comparing 19th century and 21st century US GDP growth is a very good comparison. That is essentially comparing a fast-growing developing country to a slow-growing advanced economy. If I had to pick one or the other to live in, I would probably go with the one that has safe drinking water, antibiotics, vaccinations, relatively painless dentistry, and air conditioning.