The difference between science and most other areas of life is not that scientists don’t make mistakes, but that when they do there is a reasonable chance they will eventually admit and correct it. Even if they don’t the scientific community will eventually recognise the error and move on. Sometimes this is quick, sometimes slow, but it will occur. Sadly the same is often untrue in other areas.

The contrast is thrown into sharp relief by two debates, united by a name while otherwise utterly different.

Stars Above

Many authors like to refer to the sun as a very ordinary star, usually as part of a process of putting us in our place against the scale of the universe. It was once thought that this was true – some of the stars we can see are larger and brighter, others smaller and dimmer. However, as our telescopes got better we started to realise that there were a lot more smaller and dimmer stars out there – it is just that most were too small and dim to see with the naked eye, or even a previous generation of telescopes. The sun is, in fact, brighter than the vast majority of stars in our galaxy, and probably everywhere.

On the other hand it is true that, while not many stars are more massive than the sun, there are a tiny number that are much more massive, in a few cases more than a hundred times the mass of the sun. Since the luminosity of a star is proportional to its mass to the power of four a star that heavy should be putting out 100 million times as much light as the sun, making these rare objects rather significant.

This led to the question of how large a star could theoretically become. In the first half of the century Arthur Stanley Eddington calculated the “Eddington Limit” based on the luminosity of a large star. The brighter the star the more pressure it puts outward through the force of light emitted, and the harder for it to hold together. Eddington believed that if a star was so massive its brightness exceeded his limit it would quickly throw off large amounts of mass, bringing itself back under.

This was happily accepted until the our capacity to estimate the mass of really large stars produced evidence of several stars existing above the limit. The most famous of these, η-Carina is not exactly a happy camper of a star, having thrown off huge amounts of mass during the 19th Century, and is generally anticipated to become a supernova very soon (in astronomical terms). However, it nevertheless exists in defiance of the Eddington Limit, and at least at the moment does so in a fairly stable manner.

By the time this was discovered Eddington was dead, but his theory was modified to allow a higher limit. The original calculation is now called the “classical Eddington limit” and is good enough for most purposes, but a higher limit taking into account more exotic behaviour has been calculated, and all known stars fit beneath it, other than those undergoing the sort of behaviour Eddington predicted.

This is how it should work – a theory confronts reality, is proven wanting and is modified (although in this case certainly not scrapped) in accordance.

Tunnels Below

Sadly, this is not how it works in urban planning. When the Bracks/Brumby state government wanted advice on urban infrastructure they turned to Sir Rod Eddington. He proposed various large scale schemes, some for major road projects, others for public transport. The centrepiece was a tollway connecting the Eastern Freeway and the Western Suburbs, much of the route via tunnels.

Aside from the commonality of name, the one link this has to the work of the other Eddington is that the cost is truly astronomical. Total costs from Eddington’s report were estimated at $18 billion, and while some of this was for rail projects the majority was for the tunnel and such projects do not have a history of coming in under budget. The then Labor Government were working on getting the western half of the project underway when they were tossed out. The new Liberal/National government shifted to prioritising the eastern half, and today released more details of what they are planning.

In the meantime sufficient evidence has emerged that, if this was science, would have killed the whole idea stone dead. The most crucial piece of this evidence is the simple fact that very few people using the Eastern Freeway actually want to get where the tollway will take them.

On average 135,000 vehicles a day use the Eastern Freeway. Limiting the discussion, for the moment, to those coming from the east, 68% head towards the city. Most of the rest go north, while just 9% go through to the west and would therefore benefit from a tunnel that enabled them to skip the intervening traffic.

So the proposal involves spending billions of dollars, creating vast flyovers at the entrance and exit that will destroy the amenity of two suburbs, plunge an urban creek into permanent shadow, promote the use of fossil fuels all to make 9% of the users of the freeway happy.

Except of course that it will actually be used by fewer than that 9%. At night, on weekends and for portions of the day traffic is quite light along Alexander Parade. Many people at these times will no doubt choose to stop at a few lights rather than pay the toll required to use the tunnel. So the actual beneficiaries will be somewhat less than 9%. It is worth noting that the proposed cost would be enough to build several new rail lines, extend existing ones and buy rolling stock of both trains and trams to improve the public transport (and therefore slash congestion) for great swathes of Melbourne.

Even while desperately trying to make the idea sound as appealing as possible Eddington was not able to come up with a cost-benefit analysis of his proposal that made it remotely positive.

To get around this small problem the government has resorted to what can only be considered fraud. Rather than stretching the truth they are simply making things up out of whole cloth. Central to this claim is that tens of thousands of drivers are actually trying to get from the eastern suburbs each day to the west and do this by “rat running” to avoid Alexander Parade.

Now rat running is real. My father drove me to school each day for five years along the Eastern Freeway (when the traffic was a good deal less than it is now). Sometimes when the traffic was too bad on Alexander Parade he would try to scoot through side streets. But he did this because he was trying to reach the university and he was using streets that had very little traffic (although crossing major roads was a problem). The government, however, is arguing that people are rat running through routes that are not only longer, but have even more congestion than Alexander Parade – namely Hoddle Street and the city. No one who has actually used Hoddle Street at peak hour could take this remotely seriously.

However, if anyone still needs convincing, all they need to do is stand at the point where Cemetery Crescent crosses Royal Parade at any time outside peak hour. Even if you believe people might rat run at peak hour, surely it should be obvious that no one takes a deeply circuitous route at times when the traffic is not too heavy. Consequently, even if the government is right and some people have chosen to divert via the CBD at the peak, everyone who would use the tunnel (and quite a few people besides) will use Cemetery Crescent at other times of the day. It is easy to see that by 10am the traffic, while still substantial, is no longer outrageously heavy. As a rule, all the cars banked up at Royal Parade after 10 get across in a single change of the lights. In other words, piddling numbers will find this project of any use outside peak hour. Since even a tunnel like this has a limited flow per hour, I wonder if it is even physically possible for the volume the government predicts to get through in the short bursts at the start and end of each day.

Paul Mees, of course, demonstrated the utter futility of this idea more effectively and with more wit than I could ever do, but he is gone and the rest of us must do what we can.

Arthur Eddington, who was such a keen cyclist he invented a measure for the achievements of long distance riders, would no doubt have been truly appalled to see his name associated with this monstrosity

My introduction to political activism occurred when I attended a rally calling on the then state government to honour it’s pledge to build a railway line down the Eastern Freeway to Doncaster. I didn’t have a lot of say in the matter, as I was a foetus at the time, but plenty of politicians would be eager to retrospectively grant me personhood, so I am going to claim it. As I grew, and particularly as I spent many hours parked in traffic on that freeway, the folly of that broken promise became utterly clear.

The calculations are not hard. Even in that era we often came to a stop 2km from the end of the Freeway (now I gather it is far worse). It took us around 15 minutes to crawl that distance at little more than walking pace. The space between drivers was at least 5m, so each lane disgorges, at peak time, about 1600 cars an hour, most of which carried just one person.

A train, on the other hand, would carry 800 people. At a rate of 2 an hour it would replace a single lane. Running every ten minutes it would be worth three lanes, solving the congestion problem at a stroke.

Certain cities have hit a sort of classical Eddington limit, becoming so large they can no longer grow and function. Others, however, have discovered that this fate can be avoided. Rather than requiring the quantum physics that allows η-Carina to exist, all they need is sensible planning policies that prioritise trains, trams and buses over single occupant cars.

Melbourne’s future as a city worth inhabiting, depends on defeating this awful proposal and placing a limit on Eddington.