Critical Mass and the Automobile

illustration by Jim Swanson

I was recently reading Chris Carlsson's book "Critical Mass: Bicycling's Defiant celebration" which is a compilation of various articles from worldwide newspapers and zines. According to one of the articles, there was a sort of proto-Critical Mass (see SocioMath's article here) in San Francisco in 1896. At the time, cyclists, or wheelmen as they seem to have called themselves, were annoyed at the lack of good roads and the ubiquity of raised tramlines in the centre of roads. They campaigned in particular for roads to be built properly so that cycling (which at the time was seen as 'the modern transport') would become easier for commuters. Their lobbying actually had some effect and the roads were modernised. Ironically of course, this paved the way (ho ho) for mass produced automobiles which eventually relegated cyclists again to second citizens of the road.

Perhaps Critical Mass now should seek to provide true cycling highways for people who would like to travel slightly farther afield (in particular suburban commuters) by building major cycle paths through cities.

I read more than a year ago about the so called National cycle network which I assumed would be a network of cycleways throughout the country, finally making it practical and easy to travel long distances by bike. My first impulse was to cycle from here across the Penines to York and lo! there is indeed a route - namely the Transpenine Trail. Unfortunately however, this route is not in any way designed for speed - the website mentions parts of the track which are 'off road'.

This morning I thought it might be a good idea to check out a slightly better route along part of the Fallowfield loop. I cycled west from Fallowfield along the disused railway line and then up to Salford Quays for a bit of a break before heading back to the city centre. The cycleway for as long as it lasts, is great - with the exception of the sporadic barriers. If only there were such a route say from south Manchester into the city centre itself:- imagine the number of people who would use this to commute.

chain and rider lubrication in Salford

Here are some links:

• Flyer for Chris Carlsson's book "Critical Mass: Bicycling's Defiant celebration"
• Chris Carlsson's website
• The Great Bicycle protest of 1896, Hank Capot
• The National Cycle Network

Interesting Music

You are listening to:

1. Elephant Gun - Beirut
2. Stay - Maurice Williams and the Zodiacs
3. She's not there - The Zombies
4. You showed me - The Turtles
5. I'm happy just to dance with you - The Beatles
6. Dimples - John Lee Hooker
7. Oliver's Army - Elvis Costello and the Attractions
8. Echo Beach - Martha and the Muffins
9. Belle qui tiens ma vie - John Renbourn group

Gunther von Hagens (Anatomist)

Dr Gunter von Hagens in front of his work (from www.bodyworlds.com )

Today, Le Fox and I were invited, through mere serendipitous fortune, to a question and answer session with the mysteriously eccentric Gunther von Hagens. For those not in the know, the Body Worlds exhibitions have been confronting taboos throughout the world with its sensationalist if not puritanical insistence on public knowledge of anatomical detail since its Japanese inception in 1995. Gunther von Hagens himself is the leading proponent of the concept of a modern renaissance man. He claims:

“The presentation of the pure physical reminds visitors to BODY WORLDS of the intangible and the unfathomable. The plastinated post-mortal body illuminates the soul by its very absence. Plastination transforms the body, an object of individual mourning, into an object of reverence, learning, enlightenment, and appreciation. "I hope for BODY WORLDS to be a place of enlightenment and contemplation, even of philosophical and religious self-recognition, and open to interpretation regardless of the background and philosophy of life of the viewer."

On Saturday night, I found myself in the extraordinary position of inquisitor in a closed session with the progenitor of Body Worlds 4 himself. My question, rather flacidly put, was: "In your exhibition, you quote Descartes' Medations on First Philosophy and allude to Vesalius' groundbreaking discoveries in the field of anatomy, in particular his direct opposition to Galen. Descartes work marked the transition from a scholastic age of philosophy to an age of rationalist foundationalism (and Cartesian dualism), while Vesalius revealed to us fundamental new discoveries relating to that most basic of questions: of what stuff are we made? Where in the history of knowledge do you place yourself, and how do you judge your legacy to future generations?" Of course, this paraphrased piece of nonsense is a dressed up version of the question I would have asked had my inexperience not entirely paralysed me with a mix of awe and stereotypical British politeness. As it was, I asked a messy question along the same lines but put with much less force and sadly lacking in eloquence. He answered rather obliquely, insisting that personal vanity did not enter into Body Worlds.

A plastinated man

Let me put my opinion on Body Worlds in some context. Initially, spurred on by the widespread pubic fervour, I was convinced by a wily Le Fox that it would be an experience not to be missed to see the public airing of Dr von Hagen's most controversial exhibition to date. With considerable misgivings and almost insurmountable cynicism, we made our way to the MoSI, as it has been rebranded, to see what there was to see. Once I'd entered the first of the four or five crowded halls, I was struck by an intense feeling of awe, my gaze settling on installations of carefully arranged muscle and connective tissue. There were certainly cringeworthy moments, not least reading Goethe quoted next to 'Gunter von Hagens (Anatomist)'. (Incidentally, when i put this to him, Dr von Hagens himself seemed noticably to cringe, placing the blame squarely on the shoulders of his wife's design of the exhibition.) I must admit however that the my general experience was overwhelmingly one of wellbeing and a greater awareness of the viscera of which we are, as human beings, composed. Interspersed between the deliberately provocative poses were some truly fascinating invitations to medical science and disease. Comparative displays of normal lungs and livers with those of smokers and drinkers were a graphic health warning and seemed to fulfill one of Dr von Hagen's stated aims of promoting greater body awareness among the general pubic. The rather disappointing truth is that in order to maximise visitor numbers, Body Worlds must rely on sensationalism for its marketing which paints it as anything but serious science. The meeting showed more than anything that Gunther von Hagens is primarily an academic with a passion for anatomy and its public understanding. The success of Body Worlds has had the unfortunate consequence of his message being subsumed by the publicity machine that surrounds him and the rabid commercialism that inevitably followed. Check out these links for more:

• The Body Worlds site
• Gunther von Hagens at Wikipedia
• BBC coverage of Gunther von Hagens' public autopsy
• Body Worlds 4 - the MoSI site

Naked as the day you died

So... Manchester Museum has covered up it's mummies. Director Nick Merriman has said that due to visitor complaints, they are now to be covered with cotton shrouds. The archaeologists and staff in the egyptology and archaeology departments (and many others) are very upset at this.

At first I was confused. This was the first headline I saw about the story:

'Fury as museum bosses cover up naked Egyptian mummies to protect 'sensitivities' of visitors'

My initial thought was something to the effect of 'stupid puritans even hate dead naked people.' However, reading between the lines of this rather biased first article, I suddenly realized I'd stumbled upon an issue I was very familiar with- the repatiration of human remains.

Working at the archaeological site of a Native American village for many years, I was well versed in NAGPRA (Native American Graves Repatriation Act) and I admit that when I first came to England, and saw human remains on display- probably these very mummies in fact, because I first lived in Manchester- I was very shocked. Not because they were naked, but I had been schooled in the idea that putting human remains on view was entirely disrespectful and innapropriate.

I think that this article from the Guardian gives a more balanced view.

Native American bodies- skeletons, etc- used to be the centre of many American museum exhibitions, and I often received phone calls from elderly museum goers who recalled viewing them on display at our sister museum downtown. They wanted to know where the 'dead Indians' had gone and how dissapointed they were to not be able to show their grandchildren. I would swallow and politely inform them that this was not appropriate any more and that the bodies had most likely been returned to their descendants and reburied.

So... what do I think about this? Just because something has always been done doesn't mean it's right. If there are some descendents of the mummies- indigenous people of Egypt, etc- who protest them being on show then I say they should be taken off display and returned. This freaks a lot of archaeologists out because they say that they'll lose their collections and chance for scientific study. Well even though I love archaeology, I can whole heartedly admit that it is a product of colonialism and was mainly insitited to reinforce its hegemony through it's 'discoveries'- to make indigenous peoples an other, regulat them to the past, and take away the rights of their descendents. Well, that's its worst side. At it's best, it teaches us important lessons about the past and connects us to it.

I've pretty much gotten it into my head that England/Europe is ahead of America in many ways (fashion, gay marriage, health care, etc) but in this case I'm really surprised that so many people are being so old school and raging against the machine. Mummise rank right up there with dinosaurs, in attracting families and others to gawk at museum collections. I'd think that museums would want to try to find a more meaningful way to attract and engage their audiences. After working in museums for over seven years, I don't think I'm being too niave about this.

Guerilla Gardening: resistance is fertile

The other day, Le Fox and I made our way down to Manchester's Urbis to check out their new exhibition on Manga. Having seen the exhibition (which to be honest seemed to be aimed mostly at the emo-kids in the Cathedral gardens outise), we wandered upstairs to kill a little more time. To my pleasant surprise they had an exhibition about Urban Gardening. It seems that I was not alone in my desire for the greening of Manchester's city centre - there were a great many tips for what to grow in confined balconies and window boxes. (No doubt the whole exhibition was a passionate response to Sociomath's Urban Orchards post.) What intrigued me most, however, was a small corner of the exhibition devoted to so called Guerilla Gardening. It seems as though people as despserate for green space as me had decided upon a more pro-active strategy than posting rants on a blog. They instead congregate on what is considered by them to be wasteland and plant trees, herbs, vegetables and flowers in an effort to foster a greater sense of well-being and civic pride among local residents. A couple of years ago, the hallowed airtime of the Beeb itself devoted a moment or two to the notion of guerilla gardening and in particular it's London posterboy, Richard Reynolds: a 30 year old, MG-driving, road-bike riding, well spoken former advertising executive. Have a look at a slightly tongue in cheek seven minute documentary below about guerilla gardening in London.

As for the history of Guerilla gardeining, Wikipedia claims that it started with the True Levellers or Diggers as they became known. These were folk who started gardening on common land and living in cooperatives in the second half of the 17th century. I'd argue that perhaps, since these people were growing food on land that would otherwise have been used to graze cattle that they don't really embody the "pleasant mischeif" mindset of the modern Guerilla gardener. It seems that it all really started (as most vaguely radical movements) in New York in the 1970's with the Green Guerilla group transforming a private derelict lot into a garden. One of the parts of the exhibition which really caught my attention was the concept of 'seed-bombing'. The idea is to be able to plant seeds in relatively inacessible places (behind fences/barbed wire etc). Rather than trying to bypass obstacles, such areas are 'bombed' with lumps of mud and compost containing seeds. By the next year, voila: flowers aplenty! Have a look at this video of some seedbombers in Chicago.

I'm told that there are such orgainisations in Manchester. I know nothing about them. Some links:

• Richard Reynolds' blog
• Wikipedia's Guerilla Gardening Page
• Urbis' Urban gardening exhibition

The Brazil Nut Effect

Ever wondered why on packets of cereal it sometimes says something to the effect of "Please turn packet on its side to redistribute nuts evenly"? I'd always thought that this was because any of the larger particles would have sunk to the bottom. It turned out that this was in fact not the case. Yesterday was the day of the MRSC08 conference for postgraduate maths students in Manchster. One of the talks explained the so called "Brazil nut effect", the phenomenon of larger nuts rising to the top of packets of mixed nuts during transport. The following video (taken from here) shows the effect working on a brass cylinder among polystyrene foam beads.

It turns out that although gravity pulls the cylinder down relative to the polystyrene, there are granular flow effects that also push the cylinder up which are far greater than expected. I can't claim to be an expert, but the talk was incredibly interesting. (See Prof. Nico Gray's website for research about granular flows in Manchester).

Here's a slow motion version of the above video to maybe give some intuitio for what's going on. I have to admit, I still don't quite understand from where the upward force comes.

A musical Offering

You're listening to:

1. Chop Suey! - System of a Down
2. Dirge - Death in Vegas
3. Filmstar - Suede
4. One Way - Levellers
5. Dusted - Leftfield
6. Sympathique - Pink Martini
7. Black Hole Sun - Soundgarden
8. Over the hills and far away - Led Zeppelin
9. Perpetuum Mobile - Penguin Café Orchestra
10. Neighbourhood - Space

Mathematical duality

Let me set the scene. A brooding overcast morning in post-industrial Manchester. A Mancunian café underneath an old railway arch. Two large lattés. On my side of the table a physics book for mathematicians, on Le Fox's the Economist. I opened my book on at a chapter on the basics of quantum mechanics. It stated:

"A description of physical reality is made in terms of two set of objects: observables and states. A set of obsevables A, B,... will be denoted by A and states w, x, y,... by W. Each state assigns to each observable its probability distribution on the real line. This pairing (mean value) defines a duality between A and W."

I just love how physicists like to use phrases like physical reality... It reminds me of Arnold's classic book Mathematical Methods in Classical Mechanics, which I seem to remember states in no uncertain terms

Definition: The universe is a four dimensional affine space.

Which was perhaps inspired by Wittgenstein's

1 The world is all that is the case 1.1 The world is the totality of facts, not of things. etc.

In any case, I started to wonder about the notion of duality. In mathematics at least, duality seems to be reasonably well defined. The modern idea I suppose started with the idea of a vector space having a dual which might have been somehow inspired by duals of platonic solids through the reflexive property of taking duals (at least for finite dimensional spaces). But then there's also Poincaré duality for compact oriented manifolds which says that the kth and (n-k)th Betti numbers are equal (for coefficients in Z2, orientability isn't required).

The picture of foolhardiness, I then tried to give Le Fox some idea of what Poincaré duality might mean through a couple of badly explained examples messily scribbled on a napkin - decomposing a sphere into a 0-cell (point) and a 2-cell (plane) and a torus into a 0-cell, two 1-cells and a 2-cell. As her eyes slowly glazed over, I tried to think of a more concrete way of thinking of duality. Suppose that I have a bag containing ten balls. I then take four balls out of the bag. If I know I have four balls in my hand then I know that there are six balls in the bag. Knowledge of how many balls are outside the bag is therefore somehow equivalent to knowledge of how many balls are in the bag as long as we know the total number of balls. It seemed to me that these two statements were therefore in some sense dual to each other. In the back of my mind I had Poincaré duality which could be rephrased along the lines of "Knowledge of k-cells is equivalent to knowledge of (n-k)-cells as long as the space is compact and oriented...". Here it seems that knowing that there are ten balls in total and knowing that the manifold is compact play the same role, setting up the bridge between the two dual statements in each case. For finite dimensional vector spaces, the notion of the dual space can be formulated in a similar way. Given a set with the structure of a finite dimensional vector space, the space of linear functionals can be formed. This is non-canonically isomorphic to the original space, just by mapping a given basis to its dual basis. On the other hand, given the dual space, I can construct the original space again by applying the dualising process. It's one of those well known facts that a finite dimensional vector space is canonically isomorphic to its double dual (reflexivity). On one level, the analogy with the balls fits quite nicely into the first half of this: knowledge of the dual is "the same as" knowledge of the space. On another, it doesn't really work so well - how do I get a notion of 'canonical isomorphism' in this setup? I still haven't thought of an example... any ideas?

The Ontology of Blogging

I stumbled upon this great Rocketboom video of Dave Weinberg giving a talk on mass media and blogging. Enjoy!

Artificial Ball lightning

A few years ago, a friend of mine and I decided to try and create artificial ball lightning in a microwave. All you need is a grape, a microwave and a knife.

WARNING: Attempting this could impair your health and that of your microwave! Approach with EXTREME CAUTION!

1. Cut the grape in half so that there is only small piece of skin attaching the two halves together and they look like a pair of bongo drums.
2. Take the tray out of your microwave.
3. Put the grape in your microwave with the wet faces up.
4. Start the microwave and have your finger on the stop button.

You should see a bright ball and maybe some licks of flame appearing within a second or two. I remember scortching the top of the microwave the last time I tried this so be sure to have a finger on the stop button. I'm not totally sure the physics behind the whole thing. The explanation my friend had was that the microwave sets up a standing wave inside the microwave which has around the right wavelength to create a big potential difference between the two grape surfaces. Eventually, as some of the water in the grapes boils, steam is ejected. In the presence of such a large potential difference, this ionises and forms a plasma for a split second. I'm still not totally convinced that this is actually what's going on, but I have no better explanation.

It turns out that it works even better when you have a flame in your microwave. The gas in the flame ionizes very easily and it's even possible to contain the plasma in a vessel of some sort for some time. Here's a video of someone trying it with a match:

Here's what I think happens:

The microwave keeps giving electrons in the hot gas enough energy to escape their nuclei. When these electrons return, they give off a load of energy in the form of electromagnetic radiation, some of which is the light you see. Presumably different burning materials give different parts of the characteristic spectrum (and so different colours...)

Le Fox, I would guess that if your chimney is struck by lightning when you have a fire in the fireplace, much the same things happens...

I could well be wrong...

See here for a good explanation of a similar grape experiment (with diagrams!).