Geoffrey West: The theoretical physicist with the grand unified theory of cities

Geoffrey West giving a talk in Rekjavik in 2011. Image: Árni Torfason via Flickr.

So, here's a thing. If you double the size of a city, then you don't quite double its infrastructure. If a city of 1m expands to become one of 2m, then the number of, say, petrol stations it has per person will fall by approximately 15 per cent.

This rule of thumb carries over to all sorts of other stuff: the size of the road network, the length of its electrical cables, the size of its sewer system... The more people you have, the less of any given resource each of them will need.

You can probably get your head round this fairly easily: we're all familiar with economies of scale. But bear with me, because it's about to get weirder.

That's because there are other things that increase as a city grows – and the magic number this time is exactly the same. If you double the size of a city, the average wages will increase by approximately 15 per cent. So will the number of patents logged. So will crime. So will energy consumption. So will the number of AIDS cases. For a city, it turns out, growth is kind of a good news/bad news deal.

“The problem of the 21st century is urbanisastion

All this is the contention of Professor Geoffrey West: an English-born theoretical physicist, now working at the Santa Fe Institute in New Mexico. A few years ago he turned his attention to the urban world, set up a team to gather numbers on cities all over the world, and started crunching the hell out of them. His goal, he explained in a 2011 TED talk, was nothing less than universally applicable, grand unified theory:

"My provocative statement is that we desperately need a serious scientific theory of cities. [That] means quantifiable, relying on underlying generic principles that can be made into a predictive framework. That's the quest."

Most of West's research has involved elementary particles, and even though his attention has long since moved onto subjects as diverse as cities, corporations and biology, he says that he still thinks of himself as a physicist: he just wants to bring that paradigm to more complex systems. Physics, he tells me, “is about simplicity. You can encapsulate enormous amounts of data and concepts – the origins of the universe, a theory of everything – in a single equation".

A slide from West's Ted talk, showing how employment and wages increase with population.

Cities are a bit more complicated than particles of course, subject to social and political forces that are entirely independent of straightforward metrics like population size. (Even the latter is contested: West himself bemoans the fact that there isn't a single, universal definition of how to define their limits.) As a result, any two cities of similar size, but which have had radically different histories – London and Moscow, say, or New York and Jakarta – will look radically different, too.

But West's contention was that it ought to be possible to understand and predict the characteristics of a city in at least broad strokes. Even if there’s no way to predict when any given individual will die, "we ought to be able to understand why the scale of a human lifespan is 100 years". By the same token, while you can't look at London and predict the characteristics of Moscow, you should be able to use the two cities’ relative sizes to make some educated guesses about Manchester.

When he started this line of research, one of West’s questions was whether cities behaved according to biological rules: “Are cities part of biology?" he asked in his TED talk. “Is London a great big whale?"

As it turns out, though, things are rather more complicated than that. Animals obey what are known as “sub linear relationships”: if you double the size of an organism, you only need 75 per cent more energy to run it. Pound for pound, elephants are more efficient than mice, so have lower metabolic rates and longer lifespans. (West has studied this, too.)

Cities obey these rules when it comes to their infrastructure. But they invert them when it comes to social factors like wages, patents, crime and so forth, where instead they obey super linear relationships: the bigger something is, the more per capita it has. "The question you have to ask,” West says, “is why should that be when urban systems evolved independently.”

His answer is that it’s because of the thing they have in common: human beings, and the network effect you get from putting a lot of them in one place. "The bigger you are, the more interactions take place, the more we talk, and the more we can create more wealth, new ideas, and so on.”

West's research has come in for criticism. Not every animal has been kind enough to obey his laws (the crayfish stubbornly refuses). The same is true of cities, and it isn't always a matter of diverse national histories, either. Over the last couple of decades, the US has seen a lot of growth shift to the suburbs, with much of the real economic innovation coming not from highly networked and high energy places like New York or LA, but from leafy low density areas like Silicon Valley.

West’s response is that his work is simply a first draft, something he expects others to refine and build on. "Overall the response has been very positive. The only serious negative response has come from economists. But I don't think of economics as a serious science, I think they were just threatened."

Anyway, he says, it’s better to have a flawed theory than no theory at all – and coming up with one is a matter of some urgency. The one thing that stops a superlinear growth curve – and the reason we wouldn’t be better off living in one planet-wide city of 8bn people – is the limitation of natural resources. The bigger cities get, the higher living standards are, and the more we consume. (There is some evidence contradicting this in specific contexts - New Yorkers burn less petrol than the residents of Phoenix, Arizona – but it does seem, globally, to hold true.)  That means that, once in a while, we run into a cliff edge: you simply can't get any bigger at current resource levels.

Historically we've got around that through technological innovation. But the more energy hungry we get, the faster those innovations have to come to keep things moving. In other words, West told TED, "We're not only on a treadmill that's going faster: we have to change the treadmill faster and faster. The question is, can we as socio-economic beings avoid a heart attack?"

The grand unified theory of cities isn't going to solve that all by itself. But it could make a contribution, by offering some clues as to how we maximise growth while minimising energy usage, West says. "The purpose of urban planning is finding a way to minimize our distress while maximising our interactions."

Previous attempts to begin new cities from scratch – from Canberra to Milton Keynes to Brasilia – have initially been a failure. It’s only after half a century or more of “iteration and organic growth that they began to take on a certain well-being,” West notes. Today, though, we don't have 50 years: around a million people are estimated to be moving to cities every week, and China is aiming to build hundreds of new settlements over the next couple of decades. 

"The problem of the 21st century is urbanisation," West concludes. "Climate change is actually a supplementary problem to understanding cities.” You wouldn’t build an aeroplane without doing some science, he notes – but when it comes to our urban habitats, “that is pretty much what we've done in the past". If we're to survive the 21st century, it might be time for a change in approach.

For more like this, follow CityMetric on Facebook or Twitter. Go on, we're lovely.

 

 
 
 
 

Barnet council has decided a name for its new mainline station. Exciting!

Artist's impression of the new Brent Cross. Image: Hammerson.

I’ve ranted before about the horror of naming stations after the lines that they’re served by (screw you, City Thameslink). So, keeping things in perspective as ever, I’ve been quietly dreading the opening of the proposed new station in north London which has been going by the name of Brent Cross Thameslink.

I’ve been cheered, then, by the news that station wouldn’t be called that at all, but will instead go by the much better name Brent Cross West. It’s hardly the cancellation of Brexit, I’ll grant, but in 2017 I’ll take my relief wherever I can find it.

Some background on this. When the Brent Cross shopping centre opened besides the A406 North Circular Road in 1976, it was only the third large shopping mall to arrive in Britain, and the first in London. (The Elephant & Castle one was earlier, but smaller.) Four decades later, though, it’s decidedly titchy compared to newer, shinier malls such as those thrown up by Westfield – so for some years now, its owners, Hammerson, have wanted to extend the place.

That, through the vagaries of the planning process, got folded into a much bigger regeneration scheme, known as Brent Cross Cricklewood (because, basically, it extends that far). A new bigger shopping centre will be connected, via a green bridge over the A406, to another site to the south. There you’ll find a whole new town centre, 200 more shops, four parks, 4m square feet of offices space and 7,500 homes.

This is all obviously tremendously exciting, if you’re into shops and homes and offices and not into depressing, car-based industrial wastelands, which is what the area largely consists of at the moment.

The Brent Cross site. Image: Google.

One element of the new development is the new station, which’ll sit between Hendon and Cricklewood on the Thameslink route. New stations are almost as exciting as new shops/homes/offices, so on balance I'm pro.

What I’ve not been pro is the name. For a long time, the proposed station has been colloquially referred to as Brent Cross Thameslink, which annoys me for two reasons:

1) Route names make rubbish modifiers because what if the route name changes? And:

2) It’s confusing, because it’s nearly a mile from Brent Cross tube station. West Hampstead Thameslink (euch), by contrast, is right next to West Hampstead tube.

Various other names have been proposed for the station. In one newsletter, it was Brent Cross Parkway; on Wikipedia, it’s currently Brent Cross South, apparently through confusion about the name of the new town centre development.

This week, though, Barnet council quietly confirmed it’d be Brent Cross West:

Whilst the marketing and branding of BXS needs to be developed further, all parties agree that the station name should build upon the Brent Cross identity already established. Given the station is located to the west of Brent Cross, it is considered that the station should be named Brent Cross West. Network Rail have confirmed that this name is acceptable for operational purposes. Consequently, the Committee is asked to approve that the new station be named Brent Cross West.

Where the new station will appear on the map, marked by a silly red arrow. Image: TfL.

That will introduce another irritating anomaly to the map, giving the impression that the existing Brent Cross station is somehow more central than the new one, when in fact they’re either side of the development. And so:

Consideration has also been given as to whether to pursue a name change for the tube station from “Brent Cross” to “Brent Cross East”.

Which would sort of make sense, wouldn’t it? But alas:

However owing to the very high cost of changing maps and signage London-wide this is not currently being pursued.

This is probably for the best. Only a handful of tube stations have been renamed since 1950: the last was Shepherd’s Bush Market, which was until 2008 was simply Shepherd's Bush, despite being quite a long way from the Shepherd's Bush station on the Central line. That, to me, suggests that one of the two Bethnal Green stations might be a more plausible candidate for an early rename.


At any rate: it seems unlikely that TfL will be renaming its Brent Cross station to encourage more people to use the new national rail one any time soon. But at least it won’t be Brent Cross Thameslink.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and also has a Facebook page now for some reason. 

Want more of this stuff? Follow CityMetric on Twitter or Facebook