I like to save up interesting links I find that are related to themes I've covered here on my blog, and then share them periodically.

To start with, here's a chart mapping the current state of the field of mathematics. Also on the subject of math, check out this video on Penrose tiling.

Cryptocurrencies like Bitcoin rely on some pretty advanced math. In this article, Balaji Srinivasan, a tireless advocate of the tech industry, discusses potential applications of their underlying blockchain technology:

public blockchains are massively multiclient databases, where every user is a root user. They are useful for storing shared state between users, particularly when that shared state represents valuable data that users want to export without fail — like their money.

The interoperability is a huge advantage over conventional databases and other online services, in his view.

Another prominent figure in the cryptocurrency world, Vitalik Buterin, reflects on 2020:

As life "away from keyboard (AFK)" has gotten much more constrained and challenging, the internet has been supercharged, with consequences both good and bad. ...  
in the 21st century, the lines between "private" and "public" are once again rapidly blurring. Governments are behaving more like market actors, and corporations are behaving more like governments.

Joseph Tainter and Peter Turchin are scholars who study societal crises and collapses. It's probably fair to say that their ideas are relevant at the moment. One of Tainter's key points is that societies get more complex over time and eventually the resulting lack of flexibility becomes a vulnerability. One of Turchin's key points is that the size of the would-be ruling class grows more quickly than the number of available leadership positions; as competition for high-status positions intensifies, the stability of the overall society is compromised.

On a more upbeat note, VC and essayist Paul Graham shares about how his life changed after having kids. Whether in families, businesses, or communities, I think keeping the next generation in mind is very important. To survive and thrive long-term, organizations need to be intentional about passing on both leadership skills and positions of power. Starting afresh each generation loses the benefits of institutional knowledge.

I'm not going to include too many links about the Covid pandemic and its possible aftermath, but here's one suggesting that decamping from the priciest cities could be a significant trend. Here are some semi-related thoughts. Hand in hand with remote work, here's a virtual museum to enjoy, while we wait to be able to travel to real ones again. Also, Megan McArdle is thankful for supply chains and the people who manage them, and the way they kept working through 2020.

This is a nice article from my hometown's tourism department about paddling among the islands just upriver from the city. I've been enjoying this series on how things like iron and grain were produced in the classical and medieval world. And here's a neat compilation of factoids and links on "rewilding".

In international news, Ethiopia is building a massive dam on the Nile River (although I don't know how the civil war there will affect progress on it). It's a source of tension in the region of northeast Africa, but this article suggests it could eventually lead to more cooperation by increasing the importance of diplomatic negotiations on water management.

Turning from water to fire, this article explains how controlled burns can be an invaluable tool to avoid uncontrolled megafires; it says that the state of California has a "burn backlog" of 20 million acres. However,

planning a prescribed burn is cumbersome. A wildfire is categorized as an emergency, meaning firefighters pull down hazard pay and can drive a bulldozer into a protected wilderness area where regulations typically prohibit mountain bikes. Planned burns are human-made events and as such need to follow all environmental compliance rules.

I believe Canada's immigration system gets a lot of things right. One of those things is private refugee sponsorship.

Private sponsorship gives citizens the power to offer refugees a new life in Canada. It is an alluring and unique alternative to resettlement by the United Nations, which in 2019 resettled less than one per cent of the world’s 20 million refugees.

I was reminded of Hans Rosling by the statement here that, "given the scale of what we have achieved already and what is possible for the future, I think it’s irresponsible to only report on how dreadful our situation is."

Culinary applications of seaweed is something I've mentioned in a previous post. Last but not least, this paper on the balance between kelp beds and sea urchins in marine ecosystems adapted my implementation of cellular automata in a spreadsheet in their modelling. It's always nice to be cited!