Why are medieval buildings made of squares and rectangles?

Wednesday, January 22nd, 2020

Why are medieval buildings made of squares and rectangles?

What rooms are inside real medieval castles?

Tuesday, January 21st, 2020

What rooms are inside real medieval castles?

Why do medieval buildings overhang their lower floors?

Monday, January 20th, 2020

Why do medieval buildings overhang their lower floors?

(Hat tip to Alistair, who led me down the Shadiversity rabbit hole.)

Domes are overrated

Sunday, December 8th, 2019

It is an unwritten rule of space journalism that any article about Moon or Mars bases needs to have a conceptual drawing of habitation domes, Casey Handmer notes, but domes are overrated:

Domes feature compound curvature, which complicates manufacturing. If assembled from triangular panels, junctions contain multiple intersecting acute angled parts, which makes sealing a nightmare. In fact, even residential dome houses are notoriously difficult to insulate and seal! A rectangular room has 6 faces and 12 edges, which can be framed, sealed, and painted in a day or two. A dome room has a new wall every few feet, all with weird triangular faces and angles, and enormously increased labor overhead.


It turns out that the main advantage of domes — no internal supports — becomes a major liability on Mars. While rigid geodesic domes on Earth are compressive structures, on Mars, a pressurized dome actually supports its own weight and then some. As a result, the structure is under tension and the dome is attempting to tear itself out of the ground. Since lifting force scales with area, while anchoring force scales with circumference, domes on Mars can’t be much wider than about 150 feet, and even then would require extensive foundation engineering.

Once a dome is built and the interior occupied, it can’t be extended. Allocation of space within the dome is zero sum, and much of the volume is occupied by weird wedge-shaped segments that are hard to use. Instead, more domes will be required, but since they don’t tesselate, tunnels of some kind would be needed to connect to other structures. Each tunnel has to mate with curved walls, a rigid structure that must accept variable mechanical tolerances, be broad enough to enable large vehicles to pass, yet narrow enough to enable a bulkhead to be sealed in the event of an inevitable seal failure. Since it’s a rigid structure, it has to be structurally capable of enduring pressure cycling across areas with variable radii of curvature without fatigue, creep, or deflection mismatch.

A Nobel-winning economist goes to Burning Man

Wednesday, October 16th, 2019

Economist Paul Romer went to Burning Man:

It was the first time that Mr. Romer, the former chief economist of the World Bank, had attended the annual bacchanal.

A week earlier, there was hardly anything here, in the remote desert of northwest Nevada. Then tens of thousands of people had just shown up, many in the middle of the night. They had formed an instant city, with a road network, and a raucous street life, and a weird make-do architecture.


To economists, cities are labor markets. And labor markets can’t function when there are no roads leading workers out of their favelas, or when would-be inventors never meet because they live in gridlock.

Mr. Romer’s answer is to do with this moment what Burning Man does every summer: Stake out the street grid; separate public from private space; and leave room for what’s to come. Then let the free market take over. No market mechanism can ever create the road network that connects everyone. The government must do that first.


Most of the structure that has been added since feels invisible to the people who come: the streets that are surveyed to be exactly 40 feet wide, the plazas that steer people together without crowding them, the 430 fire extinguishers around town, each tracked by its own QR code.


After 1996, the founders also began putting up a fence around the city, a pentagon with perfectly straight sightlines. Nominally, it is a “trash fence,” catching debris before it blows into the desert. But it also defines the edge of the city, so that it is possible to stand at the boundary line and stare out into an open desert uncluttered by tents or plywood art. The fence is an urban growth boundary. It is as much about keeping out interlopers as keeping people in.

America’s urban rebirth is missing a key element

Monday, July 22nd, 2019

America’s urban rebirth is missing a key element: births:

Since 2011, the number of babies born in New York has declined 9 percent in the five boroughs and 15 percent in Manhattan. (At this rate, Manhattan’s infant population will halve in 30 years.) In that same period, the net number of New York residents leaving the city has more than doubled. There are many reasons New York might be shrinking, but most of them come down to the same unavoidable fact: Raising a family in the city is just too hard. And the same could be said of pretty much every other dense and expensive urban area in the country.

In high-density cities like San Francisco, Seattle, and Washington, D.C., no group is growing faster than rich college-educated whites without children, according to Census analysis by the economist Jed Kolko. By contrast, families with children older than 6 are in outright decline in these places.

Affordability has its costs

Saturday, February 2nd, 2019

Besides its obvious shortcomings, Los Angeles has a number of subtle problems that go back to decisions made long ago:

Much of the Los Angeles area would be better today if early city fathers had realized how valuable the property would eventually become. Los Angeles has quite high population density these days, but lacks urban amenities. The San Fernando Valley on the north side of the city of Los Angeles, for instance, was built up under the assumption that it would remain a rural retreat from the big city, but it now has over 1.75 million residents.

In contrast, Chicago was laid out after its 1871 fire by men like Daniel Burnham who took “Make no little plans” as their motto. L.A. wasn’t. And it’s hard to fix urban-planning mistakes afterward.

To take a seemingly trivial example, Chicago, where I lived from 1982 to 2000, was set up with most streets having sidewalks, and the sidewalks are usually wide enough for two people to walk abreast while conversing. In contrast, sidewalks on residential streets in Los Angeles often peter out at the developers’ whims, and those that exist are usually a little too narrow for two people. So pedestrians end up conversing over their shoulders.

One reason for the sidewalk shortage is that Los Angeles was the first major city in America to develop after the automobile.

Another is that much of it was laid out to be affordable after the stock-market crash of 1929. That introduced a more democratic, less elitist ethos. There’s a lot to be said for the remarkable living standards of average people in postwar L.A., but the city is paying the price today for cutting corners back then.

Chicago, in contrast, was mostly built during the era before the New Deal when upscale bourgeois values dominated tastes. For instance, my Chicago condo was in a three-story brick building on an elegant block of other three-story brick buildings. It was a very respectable-looking block, with every building striving to live up to proper bourgeois standards.

This doesn’t mean that everybody can keep up appearances at all times. My Chicago condo had been built in 1923 with optimistic touches like nine-foot ceilings. During the Depression, the owners must have been ruined as the units were split up into two apartments. But a couple of generations later, the building was rehabbed, and the tall ceilings and other generous touches were still there.

Los Angeles, in contrast, reflects an odd combination of mass-market needs and celebrity tastes.

In 1915, Charlie Chaplin, rapidly becoming the most famous man in the world, lived in Chicago a couple of blocks from where my old condo would go up. But in 1916, as filmmakers realized the advantages of sunshine, he moved from Chicago to Los Angeles.

The movies did in the chance of Los Angeles developing physically along bourgeois lines. Film people valued privacy and self-expression. Screenwriter Nathanael West’s 1939 novel Day of the Locust complained of the excessive diversity of Hollywood houses:

But not even the soft wash of dusk could help the houses. Only dynamite would be of any use against the Mexican ranch houses, Samoan huts, Mediterranean villas, Egyptian and Japanese temples, Swiss chalets, Tudor cottages, and every possible combination of these styles that lined the slopes of the canyon.

One of the most popular architects of celebrity homes was an African-American named Paul Revere Williams whose view, in contrast to the more academically celebrated Los Angeles architects such as Schindler and Neutra, was that his movie-star clients paid him to make their whims come true. So if, say, Frank Sinatra desired a Japanese Modern house with superb acoustics for his state-of-the-art stereo, Williams would figure out how to give the client what he wanted.

Another need celebrities have is privacy from tourists. Not having a sidewalk in front of your house for your stalkers to assemble upon makes sense if you are a world-famous actor.

The peculiar needs of movie stars influence everybody else’s tastes in L.A., with generally unfortunate results. If you are in constant danger of being pestered by crazed fans, it can be a good idea to go everywhere by car. But not being able to walk down your own street without risking being hit by traffic is a dumb idea if you are a nobody.

One lesson from Los Angeles ought to be that it’s hard to retrofit urban-planning mistakes made for reasons of affordability and expedience.

For example, the Los Angeles River, a floodplain that is dry most of the year, almost washed the city away in the 1938 flood. The Army Corps of Engineers were called in and rapidly built the notorious concrete ditch that is now the L.A. River to keep, say, Lockheed from being carried out to sea in the next deluge, causing America to lose the upcoming war.

After the war, newer desert communities like Scottsdale and Palm Springs realized that it makes more sense to convert natural flood channels into parks and golf courses that can absorb runoff. Moreover, the 1994 earthquake in Los Angeles demonstrated that putting up apartment buildings on the old sand and gravel riverbed had been a bad idea, as numerous apartment buildings near the river collapsed.

For decades, public-spirited Angelenos have generated countless plans to replace the ugly concrete culvert. But to do that would require a broader channel, which would demand using eminent domain to purchase all the very expensive real estate along the river. And so nothing ever gets done.

Similarly, it’s hard to undo affordable-housing construction, unless it happens to be in a hugely valuable location, such as along the beach. Gentrification is most likely where there’s something to gentrify.

For instance, Van Nuys in the heart of the San Fernando Valley was built as an affordable place for people who couldn’t afford cars. I recall it in the 1960s being a dump.

Driving through Van Nuys last week, it was still the same dump.

Affordability has its costs.

Why Is American mass transit so bad?

Friday, December 14th, 2018

Why Is American mass transit so bad? It’s a long story:

One hundred years ago, the United States had a public transportation system that was the envy of the world. Today, outside a few major urban centers, it is barely on life support. Even in New York City, subway ridership is well below its 1946 peak. Annual per capita transit trips in the U.S. plummeted from 115.8 in 1950 to 36.1 in 1970, where they have roughly remained since, even as population has grown.

This has not happened in much of the rest of the world.


What happened? Over the past hundred years the clearest cause is this: Transit providers in the U.S. have continually cut basic local service in a vain effort to improve their finances. But they only succeeded in driving riders and revenue away. When the transit service that cities provide is not attractive, the demand from passengers that might “justify” its improvement will never materialize.


[The Age of Rail] was an era when transit could usually make money when combined with real-estate speculation on the newly accessible lands, at least in the short term. But then as now, it struggled to cover its costs over the long term, let alone turn a profit. By the 1920s, as the automobile became a fierce competitor, privately run transit struggled.

But public subsidy was politically challenging: There was a popular perception of transit as a business controlled by rapacious profiteers—as unpopular as cable companies and airlines are today. In 1920, the President’s Commission on Electric Railways described the entire industry as “virtually bankrupt,” thanks to rapid inflation in the World War I years and the nascent encroachment of the car.

The Depression crushed most transit companies, and the handful of major projects that moved forward in the 1930s were bankrolled by the New-Deal-era federal government: See the State and Milwaukee-Dearborn subways in Chicago, the South Broad Street subway in Philadelphia, and the Sixth Avenue subway in New York. But federal infrastructure investment would soon shift almost entirely to highways.


It is not a coincidence that, while almost every interurban and streetcar line in the U.S. failed, nearly every grade-separated subway or elevated system survived. Transit agencies continued to provide frequent service on these lines so they remained viable, and when trains did not have to share the road and stop at intersections, they could also be time competitive with the car. The subways and els of Chicago, Philadelphia, New York, and Boston are all still around, while the vast streetcar and interurban networks of Los Angeles, Minneapolis, Atlanta, Detroit, and many others are long gone. Only when transit didn’t need to share the road with the car, and frequent service continued, was it able to survive.


All of these [systems introduced in the 1970s] featured fast, partially automated trains running deep into the suburbs, often in the median of expressways. With their plush seating and futuristic design, they were designed to attract people who could afford to drive.

But these high-tech systems were a skeleton without a body, unable to provide access to most of the urban area without an effective connecting bus network. The bus lines that could have fed passengers to the stations had long atrophied, or they never existed at all. In many cases, the new rapid transit systems weren’t even operated by the same agency as the local buses, meaning double fares and little coordination. With no connecting bus services and few people within walking distance in low-density suburbs, the only way to get people to stations was to provide vast lots for parking. But even huge garages can’t fit enough people to fill a subway. Most people without cars were left little better off than they had been before the projects, and many people with cars chose to drive the whole way rather than parking at the station and getting on the train.


Service drives demand. When riders started to switch to the car in the early postwar years, American transit systems almost universally cut service to restore their financial viability. But this drove more people away, producing a vicious cycle until just about everybody who could drive, drove. In the fastest-growing areas, little or no transit was provided at all, because it was deemed to be not economically viable. Therefore, new suburbs had to be entirely auto-oriented.

The inventor who plans to build a city under the sea

Thursday, September 27th, 2018

Phil Nuytten has built submarines and diving suits, but now he’s planning to build a city under the sea:

An underwater city is cool, but I’m not sure how much sense it makes. He does mention siting it on a thermal vent though, for “free” energy via a Stirling engine.

Focusing less on reducing crashes and more on reducing fatalities

Friday, July 6th, 2018

The rate of people severely injured or killed in traffic accidents in Sweden has tumbled by about two-thirds since officials there started rethinking the problem two decades ago:

Anders Lie, a traffic specialist at the Swedish Transport Administration, says his country has managed to make its roads safer through its unconventional approach to traffic oversight: focusing less on reducing crashes and more on reducing fatalities.

“People will make errors and mistakes all the time,” Mr. Lie says. Thus, he says, traffic laws and infrastructure need to be designed with those errors in mind.

For example, in the U.S., people often walk or bike alongside cars legally traveling 45 miles an hour, Mr. Lie says. A better speed limit in such zones would be 25 mph, he says, citing research published by the Swedish Transport Administration in conjunction with the European New Car Assessment Program, an association of governments and consumer and motoring groups that tests vehicles and sets crash standards.

The risk of a pedestrian being killed by a vehicle traveling 18 to 25 mph is “very very small,” he says, citing the same research. Speeds in that range are acceptable for residential areas, he says. But city traffic, he says, should be capped at 30 mph, and freeway traffic at 50 mph.


Many strategies being deployed in Sweden are simple but grounded in science: lower speed limits, tougher drunken-driving laws, a more-rigorous approach to driver’s education. Redesigning roads can be more effective than attempting to change driver behavior, officials have found. Sweden has invested heavily in installing guardrails, which reduce the potential for head-on collisions, and roundabouts, which eliminate accidents typical of crossroad-type intersections. Mr. Lie says that on wide roads where median guardrails have been added, and where previously nothing divided the opposing lanes, fatalities have plunged 80%.

We have to be able to talk about cars, too

Tuesday, January 30th, 2018

Cars, not subways, seem to be what the people need — in most of the US, at least:

A 2011 Brookings Institute study (PDF) found that in the 100 largest U.S. metro areas, only 22% of low- and middle-skill jobs were accessible by public transit in under 90 minutes, suggesting that today’s working-class riders cannot access needed opportunities. And a new study (PDF) released in March 2014 by the Urban Institute found that public transit access had little effect on economic outcomes. While tracking households that had participated in two federal housing voucher programs, it found that car owners were twice as likely as transit users to find jobs and four times likelier to retain them. Car-owning households were also able to locate near better neighborhoods and schools. This reaffirmed previous work by the Progressive Policy Institute arguing that car ownership plants the seeds for upward mobility.


“In the academic research, the dominant ideas have been about improving and investing in transit,” [one of the Urban Institute study’s authors, Rolf Pendall] told the Washington Post. “But I think we have to be able to talk about cars, too.”


Another idea might be subsidizing actual car ownership, something raised as a thought experiment last decade by transportation consultant Wendell Cox. He argued that providing cars to every American transit user would cost $10 billion, compared to the $25 billion spent annually on transit subsidies, and would increase people’s mobility. Cox didn’t go so far as to suggest actually giving away cars, but a minor subsidy program could mirror the voucher-based model of other government services. This would enable poor people to shop the private car market, rather than being consigned to government transit, and would be cheaper, he argued, even when accounting for road expansions needed for the extra traffic.

Of course, increasing car use wouldn’t be feasible in some places. If New York City, San Francisco, or one of America’s few other dense cities started encouraging everyone to drive, they’d be wracked with even worse gridlock than they have now. But most cities — especially ones with populations below 100,000 — don’t have nearly these traffic levels. Their transportation problems are defined less by over-driving, than by the fact that they even attempt to sustain comprehensive public transit.

My hometown of Charlottesville, VA, is a great example. The 43,000-person, 10-square-mile city currently operates a $6 million bus system. Its daily ridership averages under 7,000, and runs along 10 routes. Like elsewhere, the system includes full-size buses, salaried drivers, a fancy central terminal, and a morning-through-night schedule. Also like other systems, it serves a city where most housing is suburban in style, and where increasing density is discouraged politically.

Together, these factors make it wildly inefficient.

That emphasis is mine, and I think the emboldened factoid deserves repeating: providing cars to every American transit user would cost $10 billion, compared to the $25 billion spent annually on transit subsidies.

Nobody knew where this power was coming from

Monday, January 29th, 2018

I’ve been meaning to read The Power Broker: Robert Moses and the Fall of New York (or listen to the audiobook) for some time. That book was published in 1974. Since then, Robert Caro has been working on his five-volume biography of Lyndon Johnson. The 82-year-old Caro is working on the fifth volume now:

Between January and July of 1965, he’s passed the Voting Rights Act, Medicare, Medicaid, Head Start, twelve different education bills, a liberalized immigration law and much of the War on Poverty. What he’s done is a great drama of legislative genius, almost without precedent. The Voting Rights Act: I wonder if we’d have it today — and what we have is still significant, even after the 2014 Supreme Court decision to strike down Section 5 — if there hadn’t been a Lyndon Johnson to seize that moment.

And at the same time that he was passing this legislation, he was secretly planning to escalate the Vietnam War.

It’s fascinating. I don’t know if I can write it well enough. But it’s almost unbelievable. You can see these great ambitions, which Johnson is on the way to realizing, get swallowed up by Vietnam. You can follow it almost minute by minute.

I don’t know if “a great drama of legislative genius” is how I’d describe it, but I take his point. He doesn’t regard his books as biographies, by the way:

I’ve never had the slightest interest in writing a book to tell the life of a great man. I started The Power Broker because I realized that there was this man, Robert Moses, who had all this power and he had shaped New York for forty-four years. And nobody knew where this power was coming from, and neither did I. I regarded the book as a study of power in cities.

After I finished that, I wanted to do national power. I felt I could learn about how power worked on a national level by studying Lyndon Johnson. Rightly or wrongly, I regard all these books as studies in political power, not biography.

It’s become a perverted Bizarro world

Friday, November 24th, 2017

Tim Ferriss explains why he left the Bay Area for Austin, Texas:

Indeed, I have relocated to Austin TX. After 17 years or so, I decided to leave Silicon Valley.

This answer could be a mini-novel, but suffice to say, here are a few reasons:

1) I wanted to move to Austin after college but didn’t get the job at Trilogy Software. Since 2007, I’ve visited Austin every year and felt the pull to move there each time. It a wonderful exploding scene of art, music, film, tech, food, and more. The people are also — in general — much friendlier.

2) After effectively “retiring” from angel investing 2 years ago, I have no professional need to be SF or the Bay Area.

3) Silicon Valley is often a culture of cortisol, of rushing, and of fear of missing out (FOMO). There is also a mono-conversation of tech that is near impossible to avoid (much like entertainment is some parts of LA), where every dinner has some discussion of rounds of funding, investing, and who is doing what with Uber, Amazon, or someone else. This can be dodged, but it takes very real and consistent effort. I don’t want to spend 20-30% of my daily mental calories on avoiding the mono-conversation.

4) Even though Silicon Valley has the highest concentration of brilliant people I’ve found anywhere in the world, it also has the highest concentration of people who think they’re brilliant. The former are often awesome, keenly self-aware, and even self-deprecating (let’s call that 15% of the population), but the latter are often smug, self-satisfied, arrogant, and intolerable (let’s call that 60% of the population). That ratio just no longer works for me. It’s too much. This asshole inflation usually corresponds to bubbles (I’ve seen it before), when fair-weather entrepreneurs and investors flood the scene.

5) Silicon Valley also has an insidious infection that is spreading — a peculiar form of McCarthyism masquerading as liberal open-mindedness. I’m as socially liberal as you get, and I find it nauseating how many topics or dissenting opinions are simply out-of-bounds in Silicon Valley. These days, people with real jobs (unlike me) are risking their careers to even challenge collective delusions in SF. Isn’t this supposed to be where people change the world by challenging the consensus reality? By seeing the hidden realities behind the facades? That’s the whole reason I traveled west and started over in the Bay Area. Now, more and more, I feel like it’s a Russian nesting doll of facades — Washington DC with fewer neck ties, where people openly lie to one another out of fear of losing their jobs or being publicly crucified. It’s weird, unsettling, and, frankly, really dangerous. There’s way too much power here for politeness to be sustainable. If no one feels they can say “Hey, I know it makes everyone uncomfortable, but I think there’s a leak in the fuel rods in this nuclear submarine…” we’re headed for big trouble.

6) Golden Gate and tech are terrorist targets, and I don’t like being close to the bullseye. This is based on good information from friends who work full-time in threat assessment.

7) I really like the sun and SF is foggy.

8) BBQ.

9) Austin is far more dog-friendly than SF.

10) Sometimes you need to think about the “where” of happiness and change your scenery to prompt new chapters in your life.

In the end, I absolutely LOVE the Bay Area, but it’s become a perverted Bizarro world version of what attracted me there in 2000. Many of my best friends in the world are there, and it pained me to leave, but I had to relocate for my own sanity, growth, and happiness.

Oh, and one more time: Texas BBQ.

Hope that helps clarify a bit!


Floating cities are no longer science fiction

Friday, November 17th, 2017

The New York Times is willing to describe floating cities as no longer science fiction:

Mr. Quirk and his team are focusing on their Floating Island Project in French Polynesia. The government is creating what is effectively a special economic zone for the Seasteading Institute to experiment in and has offered 100 acres of beachfront where the group can operate.

Mr. Quirk and his collaborators created a new company, Blue Frontiers, which will build and operate the floating islands in French Polynesia. The goal is to build about a dozen structures by 2020, including homes, hotels, offices and restaurants, at a cost of about $60 million. To fund the construction, the team is working on an initial coin offering. If all goes as planned, the structures will feature living roofs, use local wood, bamboo and coconut fiber, and recycled metal and plastic.

The people it prefers, it consumes

Wednesday, August 9th, 2017

The techno-commercial wing of the neoreactionary blogosphere, as Nick Land like to call it, has an obvious fondness for Pacific Rim city-states. like Singapore and Hong Kong, but these right-wing utopias have a problem. As Spandrell pointed out, Singapore is an IQ shredder:

How many bright Indians and bright Chinese are there, Harry? Surely they are not infinite. And what will they do in Singapore? Well, engage in the finance and marketing rat-race and depress their fertility to 0.78, wasting valuable genes just so your property prices don’t go down. Singapore is an IQ shredder.

The accusation is acute, Land says, and can be generalized:

Modernity has a fertility problem. When elevated to the zenith of savage irony, the formulation runs: At the demographic level, modernity selects systematically against modern populations. The people it prefers, it consumes. Without gross exaggeration, this endogenous tendency can be seen as an existential risk to the modern world. It threatens to bring the entire global order crashing down around it.

In order to discuss this implicit catastrophe, it’s first necessary to talk about cities, which is a conversation that has already begun. To state the problem crudely, but with confidence: Cities are population sinks. Historian William McNeil explains the basics. Urbanization, from its origins, has tended relentlessly to convert children from productive assets into objects of luxury consumption. All of the archaic economic incentives related to fertility are inverted.


Education expenses alone explain much of this. School fees are by far the most effective contraceptive technology ever conceived. To raise a child in an urban environment is like nothing that rural precedent ever prepared for. Even if responsible parenting were the sole motivation in play, the compressive effect on family size would be extreme. Under urban circumstances, it becomes almost an aggression against one’s own children for there to be many of them.