Nuclear structure and tetraquarks

Those working outside theoretical nuclear physics might be surprised to discover that, to this day, there remains no unified model of the atomic nucleus. Instead, a variety of techniques and models exist, each having some utility, but each becoming invalid when pushed outside its comfort zone.

For example, the Liquid Drop Model, first developed in the 1930s, provides an excellent explanation of nuclear fission by treating the neutrons and protons in a nucleus as a collective entity. The Liquid Drop Model, however, fails to explain why nuclei containing certain numbers of protons and neutrons are particularly stable. The Nuclear Shell Model, developed in 1949, provides an explanation for the latter by treating each neutron and proton as if it were an individual entity residing in a mean field created by all the other neutrons and protons in the nucleus.

The neutrons and protons in an atomic nucleus consist of quarks interacting with each other via the strong nuclear force. Hence, in principle, the fundamental theory of an atomic nucleus should be Quantum Chromodynamics, the application of quantum field theory to strong force interactions. Quantum field theory, however, is beset with difficulties when tasked with the representation of interactions, and whilst so-called perturbative renormalization provides the computational recipes to paper over these problems in Quantum Electrodynamics, (the application of quantum field theory to electromagnetic interactions), Quantum Chromodynamics becomes quite intractable when faced with nuclear structure.

A variety of nuclear models have been developed in lieu of a tractable fundamental theory, one of which is the so-called MIT Bag Model. This represents a neutron or proton as consisting of three non-interacting quarks, confined within a fixed spherical volume. The mass of a neutron or proton is then determined by summing the kinetic energies of the quarks and the potential energy of the whole bag. Each quark in the MIT Bag Model is represented as a Dirac spinor field which satisfies the relativistic Dirac equation. The quarks are therefore represented in the style of what's called first-quantized relativistic quantum theory, rather than the second quantized theory, quantum field theory proper.

Now, the standard model of particle physics considers the only possible bound states of quarks to consist of quark-antiquark pairs (mesons), and quark triplets (baryons) such as the neutrons and protons in an atomic nucleus. However, an application of the MIT Bag Model by Robert Jaffe in 1977 suggested that there may be more exotic bound quark states, such as tetraquarks and hexaquarks.

Intriguingly, physicists in Germany and Pakistan now suggest that data collected by the KEK particle collider in Japan in 2008 can best be explained by postulating that the collider created a tetraquark called Yb(10890). If so, it would demonstrate once more that a lack of fundamental understanding is not necessarily a barrier to achieving progress in physics.

Ron Dennis's brain transplant

The recently re-installed Chairman of the McLaren Group, Ron Dennis confessed to The Economist last month that "Sometimes I think I need a brain transplant because I can drive myself absolutely bonkers."

Now, whilst Ron was, of course, engaging in rhetorical hyperbole, let us, for the sake of argument, and to advance the state of medical science, assess whether there is any sense in which Ron could actually become the lucky recipient of a brain transplant.

The immediate response is that the notion makes little sense unless one advocates a type of mind-brain dualism. The continuity of personal identity, and in particular the retention of personal memories, are dependent upon neurophysiological continuity, hence there is no sense in which Ron could have a brain transplant, because it simply wouldn't be Ron afterwards. In particular, Ron would presumably be unwilling to lose those precious memories of "[going] to bed with the vacuum cleaner going because my mum wanted the house immaculate when she got up."

However, the sense of personal identity is held in the higher brain alone, which opens up the possibility of a partial brain transplant in which Ron remains Ron, but in which he could be shorn of that troubling perfectionist streak. Remarkably, such partial brain transplants seem to be possible in principle, having been successfully performed upon mice. Dr. Dorothy T. Krieger, chief of endocrinology at Mount Sinai Medical Center in New York City, performed such experiments as far ago as 1982, taking a small piece from one brain, and dropping it into a cavity in another brain. In these experiments, the donated brain cells began to grow in the cavity, sending out nerve fibres which spontaneously connected up in the right way with the rest of the brain.

Duly encouraged by Dr Krieger's ground-breaking experiments, let us briefly remind ourselves of how the human brain is structured, in order that we might identify some candidate regions for transplantation.

As David DeGrazia eloquently explains, "We may think of the brain as comprising two major portions: (1) the 'higher brain', consisting of both the cerebrum, the primary vehicle of conscious awareness, and the cerebellum, which is involved in the coordination and control of voluntary muscle movements; and (2) the 'lower brain' or brainstem. The brainstem includes the medulla, which controls spontaneous respiration, the ascending reticular activating system, a sort of on/off switch that enables consciousness without affecting its contents (the latter job belonging to the cerebrum), as well as the midbrain and pons."

Could the cerebellum be a good candidate for transplantation? It's not essential to personal identity, but on the other hand, the cerebrum is tightly integrated with the cerebellum, and the user may find it difficult to cope with an unfamiliar cerebellum:

"The cerebellum...is responsible for precise coordination and control of the body - its timing, balance, and delicacy of movement. Imagine the flowing artistry of a dancer, the easy accuracy of a professional tennis player, the lightning control of a racing driver, and the sure movement of a painter's or musician's hands...Without the cerebellum, such precision would not be possible, and all movement would become fumbling and clumsy. It seems that, when one is learning a new skill, be it walking or driving a car, initially one must think through each action in detail, and the cerebrum is in control; but when the skill has been mastered - and has become 'second nature' - it is the cerebellum that takes over. Moreover, it is a familiar experience that if one thinks about one's actions in a skill that has been so mastered, then one's easy control may be temporarily lost. Thinking about it seems to involve the reintroduction of cerebral control and, although a consequent flexibility of activity is thereby introduced, the flowing and precise cerebellar action is lost." (Roger Penrose, The Emperor's New Mind, p490).

Whilst the cerebellum, then, should be left well alone, the various components of the lower brain seem to perform modular functions, and therefore constitute more acceptable candidates for transplantation. In particular, for those wishing to alter their desires and motives, the thalamus may be the perfect candidate, for according to neurosurgeon Wilder Penfield, it provides the content of willed action. It is impossible to engage in willed action without the thalamus communicating with the relevant part of the motor cortex in the cerebrum, and whilst the relevant part of the motor cortex can be directly stimulated to produce action, doing so will yield action without a corresponding desire to perform that action. The thalamus seems to need the conscious mind, but without the thalamus, the conscious mind has no motives.

So there we have it: Ron Dennis could, if his thalamus so desired, have his thalamus removed and replaced by the thalamus of someone else, and still be Ron Dennis.

Senescence and immortality

The body of any mammal consists of an interacting collection of cell populations. These cell populations are distinguished not merely by the different types of specialised cell they contain(blood cells, liver cells, nerve cells, etc), but by the general model used by each population to maintain a steady-state. in this context, Michalowski identified two population types: Hierarchical, or H-type populations, and Flexible, or F-type populations.

There are two key properties which can be used to characterise cell populations: proliferation and differentiation. If the cells in a population are dividing (via the cellular process of mitosis), and thereby reproducing, then they are said to be proliferating. If the cells in a population are highly specialised in the function they perform, then they are said to be differentiated. Not all cells in the body of a mammal are dividing, and not all the cells in such a body are differentiated.

An H-type population contains three sub-populations: stem cells; maturing partially differentiated cells; and mature, functional cells. Stem cells are non-differentiated cells, which, when they undergo mitosis, are capable of both renewing their own numbers, and producing the progenitors of the more specialised cells in the population. Stem cells have infinite proliferative capacity by virtue of an enzyme called telomerase. In the absence of this enzyme, cells can only undergo a finite number of divisions before the telomeres on the ends of their chromosomes become excessively shortened. The maturing, partially differentiated cells are the descendants of the stem cells. These cells undergo successive divisions, and become increasingly differentiated as they do so. The mature, functional cells, are the descendants of the partially differentiated cells. The mature cells are fully differentiated, but incapable of further division. Given that the other cells in the hierarchy are dividing and multiplying, the mature cells must have a finite lifetime to maintain a steady-state in the organ or tissue. The classic examples of H-type cell populations are the hematopoietic bone marrow, the intestinal epithelium, and the epidermis.

Michalowski defined an F-type population as the opposite extreme, a population with no stem cells, in which all the cells are differentiated, and the differentiated cells are capable of undergoing further mitosis. To maintain a steady-state, the cells in such a population rarely divide, but are capable of doing so in the event of damage to the tissue or organ. The liver is often quoted as an example of such a cell population.

Michalowski also acknowledged that there is a spectrum of H-F hybrids between the two extremes, populations which both contain stem cells, and differentiated cells capable of further division. In fact, I wonder if organs such as the liver are actually H-F hybrids. The problem I have with Michalowski's F-type is that the cells are defined to possess an infinite proliferative capacity. This is only possible with telomerase, yet as I understand it, the only cells which utilise telomerase are stem cells and cancer cells. Perhaps, then, an F-type population is merely a limit to which various organs and tissues can approach.

What is interesting here is that the mammalian body possesses at least two different solutions to the problem of maintaining a population of cells in a steady-state. An H-type population is potentially immortal, (given a supply of energy for an infinite time). In contrast, in the absence of telomerase, an F-type population will evolve towards senescence after a finite time.

It's also interesting to note that, whilst mammals have evolved over millions of years by means of reproductive populations, the individual bodies which are the upshot of that evolutionary process, utilise various types of reproductive sub-population, not to evolve, but to maintain a steady-state.

The solution to Formula One's problems?

The long-term economic, political and sporting success of Formula One is dependent upon finding a joint solution to the following conundrum:

Develop a set of technical and sporting regulations which both enables the sport to be environmentally friendly, and enables cars of similar performance levels to overtake each other in dry conditions.

The current proposal on the table is to re-introduce Kinetic Energy Recovery Systems (KERS), thereby enabling the manufacturers to claim that Formula One is assisting the development of their hybrid road-car technology, and also providing drivers with a power-boost of 100bhp or so, deployable for a limited period each lap, to facilitate overtaking.

Unfortunately, if the entire field possess KERS, it is difficult to see how its deployment could be controlled to permit overtaking. Even with an extra 100bhp on tap, it is unlikely that most circuits would acquire additional overtaking spots, and the car in front would therefore simply push the KERS button in the same places as the car behind.

Perhaps, however, there's another solution, and one which goes to the root of the problem: aerodynamics. Whilst downforce is often blamed for the lack of overtaking in Formula One, it is not downforce itself which is the problem, but the turbulent wake created by the downforce-producing devices on a car. Such turbulence severely reduces the downforce created by a following car, thereby precluding the possibility of overtaking in dry conditions. If it proves impossible to legislate against downforce-producing devices, the solution is surely to smooth out the turbulent wake created by such appendages. And, crucially, the energy removed from a turbulent wake can be converted into electrical energy.

For example, a research group from City College of New York demonstrated last year that energy could be removed from both a turbulent wake and a turbulent boundary layer, and converted by piezoelectrics into a voltage. "These devices open the possibility to continuously scavenge otherwise wasted energy from the environment," claimed Yiannis Andreopoulos.

One presumes that the amount of recycled energy would be less than that recovered by KERS, but from the viewpoint of improving the quality of the racing in Formula One, the harvesting of turbulent energy is potentially the most important development to date.

To infinite safety and beyond

The National Air Traffic Services say there is "no threshold" at which volcanic ash is acceptable for aircraft. If particles are ingested into a jet engine, they clog it with molten glass, causing the engine to shut down. The International Civil Aviation Organisation recommends a no-fly zone if volcanic ash is detectable. (The Times, Tuesday April 20th)

Good news. NATS, the UK's national air traffic control service, has discovered the concept of a concentration level. Up until Tuesday evening this week, the organisation entrusted with the safe and expeditious control of aircraft within UK airspace, appeared unable to grasp the concept that a contaminant present in the atmosphere at detectable levels is not necessarily a contaminant present at hazardous levels.

Throughout this period, NATS attempted to counter growing objections within the aviation industry, with the standard, jet-out-of-jail-free card, that "Safety is paramount." Or, to complete the implicit thought process underlying such statements:

"In a risk averse culture, an uncritical, blanket approach to safety is paramount for preserving and promoting the lucrative careers of the managers and executives responsible for large industrial and technological enterprises."

On Sunday, McCabism noted that by assuming a contaminant detectable at any level must be a hazardous contaminant, NATS and the media were committing the same fallacy displayed after the Chernobyl explosion in 1986. Then, as now, the cloud of contamination was represented as homogeneous blanket extending over almost the whole of Europe. In fact, the analogy is stronger than suspected, for it transpires that the computer model used by the Met Office to predict the dispersion of the volcanic ash cloud, was actually developed in the wake of the Chernobyl accident, to model the distribution of radioactive fallout.

McCabism asked NATS last Friday to specify the maximum safe concentration level of volcanic ash, and is still awaiting a response. Happily, however, the Civil Aviation Authority has now been able to obtain an initial estimate of this figure as 0.002 grams per cubic metre.

It's good to know that the cream rises to the top, and we've got our best minds on the job at all times.

Lewis Hamilton's XXI

A number of interesting points emerged from Sunday's Chinese Grand Prix, not least of which is that the WWF have apparently now been put in charge of Formula One pace-car deployment.

Normally virtuous individuals can sometimes behave in a steely manner when they perceive themselves to be the victim of injustice, and there seemed to be more than a little of this when, just before the re-start of the race on lap 25, Jenson Button slowed the artificially concertinaed pack to the type of crawl last seen when Michael Schumacher was in the sport. The intervention of the pace-car had brought Lewis Hamilton and the Red Bulls to within striking distance of Button's McLaren, and if all three had come together at the final corner, Jenson would surely not have shed a tear.

Another revelation to arise from Shanghai is that it's ok to nail your team-mate under braking on the pitlane entry road. Racing in the pit-lane itself is also just about ok, so long as you only make one move.

Despite Button's finely-judged brace of victories in Australia and China, the true racing star of the past three Grands Prix has surely been Lewis Hamilton. In fact, Lewis has executed at least 21 on-track overtaking manoeuvres, for position, in these races alone. Not counting positions gained in pit-stops, cars overtaken on the drag to the first corner, positions gained from retirements, or places ceded by vastly slower cars, this is the count:*

Australia
Button (Lap 6, inside of turn 3)
Barrichello (Lap 11, inside of turn 9)
Massa (Lap 16, around outside of turn 2)
Webber (Lap 16, turn 3, Webber on the inside running into the gravel)
Massa (Lap 22, clipping the Ferrari's rear tyre down the pit-straight)
Rosberg (Lap 26, around the outside into turn 11)

Malaysia
Buemi (Lap 2)
Alguersuari (Lap 3)
Kobayashi (Lap 4, inside first corner)
Petrov (Lap 5, inside final corner, re-passed into turn 1 on lap 6)
Petrov (Lap 7, inside final corner)

China
Barrichello (Lap 7, Barrichello running wide into hairpin)
Webber (Lap 9, slipstream down back straight)
Vettel (Lap 11, Vettel running wide at hairpin)
Sutil (Lap 11, Sutil running wide at hairpin)
Schumacher (Lap 16, cutting inside exiting hairpin)
Webber (Lap 25, inside of final corner at the re-start)
Schumacher (Lap 26, inside of turn 9)
Petrov (Lap 27, inside of turn 9)
Kubica (Lap 29, outside down back-straight)
Rosberg (Lap 36, inside turn 9, re-passed into turn 10)

Which is something for the rest of the field to ponder as the new charter airline, RonAir, makes its first flight from Shanghai to Spain this week.

* Jonathan Noble claims that Lewis has completed 32 competitive overtaking moves in the first four races. This count perhaps includes some of categories excluded above.

Chernobyl and the volcanic ash

There's a depressing familiarity between the media's coverage of the volcanic ash cloud over Europe, and their coverage of the radioactive contamination released by the Chernobyl explosion in 1986. In both cases, the contaminant is treated as a Boolean variable, (something which is simply true or false), rather than something which is present at different levels of concentration. In both cases, the implicit media assumption is that if the contaminant is detectable at any level, then it must be hazardous.

Only some levels of radioactive contamination are hazardous, and the same principle applies to the concentration levels of volcanic ash. Whilst the levels of volcanic ash over Iceland will obviously be high, and whilst such levels of concentration have been proven to be hazardous to aircraft in the past, elsewhere the ash will be dispersed to lower levels of concentration by random diffusion and high-altitude winds. Yet look at any map of the volcanic ash distribution, and it is treated as a homogeneous blanket.

Perhaps the media, however, are simply following here the direction provided by the air traffic control and meteorological authorities, who also seem to be unforthcoming about the specific concentration levels involved. On Friday, I posed the following question to the Press Office of the UK's air traffic control service, NATS:

i) What concentration level of volcanic ash in the atmosphere is considered to be hazardous to aircraft? Presumably there is a specific figure, perhaps expressed in terms of grammes per metre cubed, such that if the concentration level is greater than that, then it is considered hazardous for aircraft to fly under these conditions.

(ii) What scientific method was used to establish this maximum safe concentration level?

(iii) What scientific method is used to assess the concentration levels of volcanic ash currently over Europe?

Suffice to say, I'm still awaiting their response...

Pat Symonds's guide to neutrino physics

In January this year, the Tribunal de Grande Instance overturned the FIA's decision to impose a lifetime ban on Flavio Briatore for his part in the Crashgate saga. Also annulled was the five-year suspension meted out to Renault's erstwhile director of engineering Pat Symonds. Despite the FIA's protestations that they would appeal this decision, an out-of-court settlement between the parties was announced this week, and as part of this settlement, Symonds was permitted to begin work immediately for any Formula One team, via his consultancy company, Neutrino Dynamics. This is good news, for most reliable Formula One observers consider Symonds to be a good egg, who simply made an error of judgement on this occasion.

Moreover, now that Symonds has clearly diversified into elementary particle physics, McCabism would like to present Pat with a handy, question-and-answer crib-sheet, which can be used to field any smart-arse questions he might be asked about neutrinos in the coming months.

Q: Pat, what's a neutrino?
A: Well, it's an elementary particle with zero electric charge and spin 1/2. It was named by Italian physicist Enrico Fermi, and means 'little neutral one' in Italian. It was originally thought to have zero mass, but it is now known to have a small positive mass. Nevertheless, individual neutrinos interact very rarely with anything else. Portuguese physicist Joao Magueijo has recently compared them to scooters, zipping through the streets of Palermo. This rather underestimates things, however, for there are 10 trillion neutrinos passing through your body every second.

Q: What's the significance of the fact that neutrinos have mass?
A: Well, for a start, it means that they don't quite travel as fast as light in a vacuum. Secondly, like many elementary particles, neutrinos possess a property called 'handedness', or 'chirality'. This means that they can be left-handed or right-handed. If neutrinos were massless, the handedness of a neutrino would be an invariant property of a neutrino throughout its lifetime, part of the definition of the particle type. Originally, it was held that neutrinos were right-handed, and anti-neutrinos were left-handed. In contrast, if neutrinos have mass, then the handedness of neutrino is a variable property; an individual neutrino can be initially right-handed, but change to being left-handed at a later time.

Q:How did scientists discover that neutrinos have mass?
A: Well, there are three different so-called neutrino 'flavours': electron-neutrinos, muon-neutrinos, and tauon-neutrinos. Oscillations between these different flavours are only possible if neutrinos have mass. Scientists found that there was a deficit in the expected number of electron-neutrinos produced by the fusion reactions in the Sun, and detected on the Earth. This deficit was eventually explained by the fact that the electron-neutrinos emitted by the Sun are oscillating between the different flavours, so that only a third of them arrive at the Earth as electron-neutrinos. Neutrino flavour oscillations are only possible if neutrinos have mass, hence neutrinos have mass. I actually got the idea of using a mass damper in Formula One from the concept of neutrino oscillations.

Q: How has the Standard Model of particle physics accommodated this revised understanding of neutrinos?
A: Well, massless neutrinos were represented by things called Weyl spinor fields, which were required to satisfy an equation called the Weyl equation. Weyl spinor fields assign an element of C² to each point in space. In contrast, if neutrinos have mass, then they are either Dirac spinor fields or Majorana spinor fields. Dirac spinor fields assign an element of C⁴ to each point in space, whilst Majorana spinor fields assign an element of R⁴ to each such point. Anything represented by real number fields in particle physics equals its own anti-particle, hence if neutrinos are Majorana spinor fields, then there is no distinction between neutrinos and anti-neutrinos.

Q: But Pat, how can you determine if neutrinos are Majorana spinor fields?
A: Well, if they were, a process called neutrinoless double-beta decay would be possible. Double-beta decay results in the twin emission of two neutrinos; if a neutrino equals its own anti-particle, then it is possible for the two neutrinos in double-beta decay to annihilate each other. Hence if we detect neutrinoless double-beta decay, neutrinos must be Majorana spinor fields. In fact, we could also infer the electron-neutrino mass from neutrinoless double-beta decay.

Detecting neutrinos, however, is a difficult task at the best of times. At Neutrino Dynamics, we've installed a large tank of ultra-pure water in a mine deep beneath Enstone, where the detector is shielded from cosmic rays. Whenever a neutrino collides with an electron in the water, the electron initially recoils faster than the speed of light in water, creating a shock wave of visible light called Cerenkov radiation. We can detect these flashes of light with photomultipliers, and thence infer the neutrino reactions. In effect, we're trying to get neutrinos to deliberately crash into atomic electrons in our tank of water.

(Additional information from Dark Side of the Universe, Iain Nicolson, Canopus, 2007.)

Air traffic control and radiobiology

Despite their superficially disparate nature, there is a striking formal similarity between air traffic control, and the processes studied in radiobiology.

In air traffic control, the objects of attention are the aircraft flight paths across a bounded region of airspace, called a sector. In radiobiology, the objects of attention are the energetic particle tracks across the bounded region of space occupied by a biological cell.

In air traffic control, there is a relationship between the number of flights passing through a sector, and the workload of an air traffic controller, and this relationship is given by a linear-quadratic function. In radiobiology, there is a dose-response relationship between the dose of radiation inflicted on a cell, and the biological response of interest, which may be the number of chromosome aberrations, DNA mutations, or the probability of cell death. For radiation of a fixed type and energy, the dose inflicted on a cell essentially corresponds to the number of particle tracks crossing the cell. Hence, the dose-response relationship is a relationship between the number of particle tracks crossing a cell, and the biological consequences. In the case of so-called chromosome translocations, a response crucially related to the probability of subsequent carcinogenesis, the dose-response relationship is given by a linear-quadratic function.

Let us elaborate on these linear-quadratic relationships a little in order to understand the reasons for such formal similarity. In the case of air traffic, the linear component of controller workload is due to (i) the number of routine flight level and airspeed instructions issued per aircraft, and (ii) the communication required with other controllers, when an aircraft is received from, or transferred to another sector. This component of controller workload is independent of the flow-rate, the number of aircraft passing through the sector per hour.

The quadratic component of controller workload is that associated with aircraft conflict-prediction and resolution; there are regulatory separation minima between aircraft, which must not be infringed. Each aircraft could be in potential conflict with any other aircraft in that same sector in the same time-window, hence this component of workload squares with the number of flights. This component of workload is clearly flow-rate dependent; at times of very low flow-rate, it will vanish.

In radiobiology, it is generally acknowledged that in those circumstances where there is a linear-quadratic dose-response relationship, the linear component arises from intra-track mechanisms, whilst the quadratic component arises from inter-track mechanisms. For example, chromosome translocations occur when genetic material is exchanged between two different chromosomes. It is generally thought that such chromosome aberrations occur because the two separate chromosomes both suffer double-strand breaks; i.e., the double-helix of DNA is thought to be broken in two separate chromosomes. The fragments from the two broken chromosomes are then exchanged, rather than spliced back to the correct chromosomes from which they originated.

There is a linear-quadratic relationship between radiation dose and the number of chromosome translocations in an irradiated cell. The linear component is due to individual particle tracks breaking two separate chromosomes. In contrast, the quadratic component is thought to be due to independent particle tracks breaking two separate chromosomes. This component squares with the dose because a break caused by one particle has a chance of interacting with a break caused by any other particle which passes through the cell within the same time-frame, (a period determined by the cycle of cellular repair processes). This component of the dose-response relationship is therefore dose-rate dependent; at low dose-rates it vanishes.

As yet, however, there appear to be no textbooks for those wishing to jointly specialise in air traffic control and radiobiology.

Exit Strategy

Just down the Worting Road from the kebab van, lies The Royal Oak, a local pub whose diminutive parking space is more than compensated for by its proud possession of two darts boards, and a pool table.

Tonight, however, within the alcove normally reserved for the quiet chink and cur-thud of Newtonian billiards, two young rock bands, Triad and Exit Strategy, will instead take their cues, and shake the rafters with a succession of belting tracks.

Despite the incontrovertible numerical implications of their name, Triad are in fact something of a quintet. They proceed to hammer through a series of excellent, self-written tracks, their lead singer having something of the Chrissie Hynde about her. The drummer is also clearly a master of his craft, and to this end has stripped to the waist. Perhaps inadvertently, this gives him the appearance of playing the drums from his bathtub.

There is something inexplicable and eldritch about the sound produced by a coordinated cluster of electric guitars. The sophistication and variation of the musical output seems somehow disproportionate to the simple digital input. It is as if each guitar is really a cage for some trapped spirit from another world, whose anger and longing for its own plane of existence, can nevertheless be trained and channelled by its Earthly guardian into a sound both ethereal and visceral.

Before Exit Strategy go on, I explain to their enigmatic rhythm guitarist, Dan, my difficulties believing in a naturalistic explanation for the sound of the electric guitar. I question how he can be capable of eliciting such sonic sophistication, to which he merely retorts, "I can't believe how you can understand Bayesian stats."

Exit Strategy's drummer, Aaron, is rather more demure that his Triad counterpart, and rather than disrobing, merely changes into his drumming tank-top. And then they're off. Peering over the top of the various friends and girl-friends, one can descry lead singer Andy, sporting a post-modern ironic combination of DangerMouse T-shirt, and nu-metal baggy shorts, a la Fred Durst. As the guitarists work their filigree magic, Andy does a funny little angry dance, and turns to commune with Aaron, who is clearly deep in the percussive zone.

Exit Strategy compose their own music, and even have a demo EP, Red Light Syndrome. It's all very impressive stuff, and one can only feel sorry for the man in the kebab van, wreathed as he is in greasy aromatic tendrils, and now musically deprived to boot.

Red Bull's intra-team tactics

Mark Hughes analyses the relative performance of Red Bull drivers, Sebastian Vettel and Mark Webber, in last Sunday's Malaysian Grand Prix, and points out that Webber was doomed from the moment he allowed Vettel to assume the inside line into the first corner. Even the pit-stops offered Webber no chance of redemption, and for the following reason:

"Within the team, the leader gets strategic preference on the timing of the stops i.e. he will be brought in first, allowing him to use the grip of his new tyres to pull further clear while his team-mate is still on his worn rubber."

This, however, raises the possibility that a driver, if closely pursued by a team-mate, could postpone his own pitstop for as late as possible, and thereby ensure that his team-mate, stopping one lap later, is guaranteed to lose track position. Doing so would allow the lead driver to pull clear whilst his team-mate struggles to extricate himself from the rest of the pack.

Curiously, in the Australian Grand Prix, just seven days previously, whilst the majority of the field pitted on lap eight, the leader, Sebastian Vettel pitted on lap nine, forcing second-placed Webber to pit on lap ten. The belated timing of Webber's stop dropped him into the pack, from which his increasingly aggressive attempts to extricate himself simply dropped him further and further behind.

Red Bull claimed after the Australian Grand Prix that they were simply being conservative with the timing of Vettel's pitstop, but the opportunity is certainly there for a driver to exploit this system to enforce dominance over a team-mate.

Autism, art, and religion

Bryan Appleyard writes an article in The Sunday Times which, at face value, appears to be about the relationship between mental illness and creativity. It is only at the end, however, that we find out what the article is really about.

Appleyard's article touches on a character called Christopher, the protagonist from a novel by Mark Haddon. Christopher is a character with Asperger's syndrome, a form of autism. All people with autism, we are informed early in the article, have a deficient capacity for empathy with other minds. After a fairly routine discussion of whether mental illness and artistic creativity stem from a common source, the reader is suddenly, without warning or justification, presented with a rather bizarre, ad hominem attack on biologist Richard Dawkins and philosopher Daniel Dennett:

Christopher is a Dawkinsian observer of the human world. He thinks that mathematics is the highest truth and he is constantly trying to reduce human behaviour to a series of rational categories.

"But the mind," he thinks at one point, "is just a complicated machine. And when we look at things we think we’re just looking out of our eyes like we’re looking out of little windows and there’s a person inside our head, but we’re not. We’re looking at a screen inside our heads, like a computer screen."

Christopher is right up there with certain philosophers of consciousness, such as Daniel Dennett. But, like them, he only sees half the picture.

I ask Haddon where he stands on the truth, sanity or otherwise of Christopher’s attitude.

"Only a very long answer would do this question,” he replies, “but I’m taking Karen Armstrong over Richard Dawkins."

Armstrong is a thinker on the side of religious insight and the fundamental mystery of the human condition; Dawkins and Dennett are emphatically not. Armstrong is right, she is on the side of sanity. Great art is the highest form of sanity, the highest form of insight into other minds.

The first thing one notices from the extract above, is that Appleyard has fundamentally misunderstood the point that Christopher was making, when he suggests that we're looking at screens inside our heads, rather than looking out through windows. By implication, Appleyard seems to think that this is an expression of eliminative materialism, a position in the philosophy of mind which holds that the brain exists, but the mind doesn't. On the contrary, Christopher's assertion is in fact a statement of what is variously called indirect realism or representative realism in the philosophy of perception. Indirect realism holds that we can only be directly acquainted in perception with our internal, sense-data representations of the external world, whilst direct realism holds that we are directly acquainted with the objects of the external world.

Whilst eliminative materialism excludes the existence of the mind, numerous other approaches in the philosophy of mind, such as functionalism, accept that the mind supervenes on the brain, but reject the idea that mental states and processes can be defined in terms of brain states and processes. Such approaches certainly cannot be accused of seeing only "half the picture."

The mystery here, is how a discussion of art and mental illness has suddenly decayed into an attack upon atheists such as Dawkins and Dennett. One might well accept that great art provides the "highest form of insight into other minds", but it is clear that Appleyard also regards art as a kind of shop-window for religion. Accordingly, we suddenly find Appleyard linking great art with "religious insight" into the "fundamental mystery of the human condition." And in this context, it should be noted that some Christian thinkers refer to the Incarnation of Jesus as 'the mystery'. For example, Andrew Louth, of whom Karen Armstrong speaks approvingly, argued that "the heart of the Christian mystery is the fact of God made man, God with us, in Christ," (Discerning the mystery: an essay on the nature of theology, p74).

It is, of course, perfectly consistent to empathise with other minds, and to appreciate great art, without in any way needing to believe that there is any religious mystery to the human condition. Failure to understand this, demonstrates an inability to understand and empathise with the secular mind.

Oksana and the Malaysian pot-holes

Lewis Hamilton was weaving more vigorously than a 19th century Lancashire power loom. To the immense detriment of the viewing audience, Oksana's reaction was not captured on camera, but it seems reasonable to conclude that she was far from impressed.

Had Lewis possibly spotted some pot-holes in the track surface, caused by a recent, unexpectedly harsh Malaysian winter? Or was he, perhaps, trying to free his left leg from the prodigious sucking power of the cockpit orifice to McLaren's Dyson-inspired F-duct? Could Lewis even have been momentarily mesmerised down the back straight by the serrated, foliar-tipped grandstand canopy, scrolling limitlessly in his peripheral vision?

In fact, the immediate cause of these strong-armed driving tactics was a moment's inattention from Lewis going into turn one, just moments after he had apparently put Vitaly Petrov to the sword. The root cause, however, was the convective rainfall on Saturday, which had relegated Hamilton's McLaren to the back of the grid for the Malaysian Grand Prix. Or, more accurately, the root cause was McLaren's misplaced assumption that meteorological predictions of convective rainfall are of equal reliability to those of frontal rainfall.

If Michael Schumacher had not been re-hydrating with a refreshing cup of Ovaltine, he would have been infused with a dewy-eyed nostalgia for the halcyon days when he was the pre-eminent driver of his generation, diagonalising the straights to deter potential assailants from contemplating passing manoeuvres.

Perhaps there is method in Lewis's madness, and he seeks to intimidate the current driver cohort in the manner patented by his hero, Ayrton Senna. On the negative side, however, the next driving infraction may well result in a stop-go penalty, like an agricultural Blackburn midfielder exhausting the referee's patience with a final minor transgression.

Only one thing is certain: Oksana will prevail.

Francisco Ayala and Easter

Former Dominican priest, Francisco Ayala was announced this week as the winner of the £1 million 2010 Templeton Prize. An evolutionary biologist and geneticist, Ayala was awarded the prize for supporting the notion that there is no contradiction between science and religion.

Interviewed by New Scientist, Ayala claims that science and religion are "two windows through which we look at the world. Religion deals with our relationship with our creator, with each other, the meaning and purpose of life, and moral values; science deals with the make-up of matter, expansion of galaxies, evolution of organisms. They deal with different ways of knowing. I feel that science is compatible with religious faith in a personal, omnipotent and benevolent God."

Writing in The Guardian, Mark Vernon places Ayala's position close to that of Stephen Jay Gould, who argued, as follows, that science and religion are 'non-overlapping magisteria':

"The lack of conflict between science and religion arises from a lack of overlap between their respective domains of professional expertise – science in the empirical constitution of the universe, and religion in the search for proper ethical values and the spiritual meaning of our lives."

If religion confined itself to making a bundle of metaphysical and ethical claims, then it could indeed be claimed that there is no overlap with the empirical domain of science. Unfortunately, however, the world's major monotheistic religions, Christianity, Islam and Judaism, have historically been supported by bundles of empirical claims about man's place in the universe, which have been falsified by the Copernican revolution in astronomy and the Darwinian revolution in biology. The claim that science and religion possess non-overlapping domains is therefore demonstrably false.

The majority of religious adherents in the world, believe that the universe was created by a supernatural being called 'God', that God answers prayers and performs miracles, and that humans have immaterial souls which survive death. Most Christians, in particular, believe that there was a man called Jesus, who was the 'son of God', and tomorrow, Easter Sunday, these Christians will celebrate their belief that this man was resurrected from the dead. Belief in such purported miracles amounts to a belief in the occurrence of certain empirical events, which are impossible according to science.

Ayala claims that "religion and science are not properly understood by some people, Christians particularly." Ayala's claim that science and religion are not in contradiction, therefore depends upon the proposition that religion is not actually what the majority of religious people in the world believe it to be.

By stripping religion of its empirical content, Ayala and Gould are engaging in a high re-definition of what religion is. In other words, they are implicitly attempting to re-define the term 'religion', so that it applies to a narrower range of beliefs. This more narrowly defined bundle of metaphysical and moral beliefs, might well be consistent with scientific belief, but this can only be achieved by changing the original and commonly understood meaning of the word 'religion'.

The second component of the philosophy espoused by Ayala and Gould is that religion has a legitimate role in ethics and morality. This, however, is as much of a logical fallacy as the notion that ethics and morality can be derived from science; one cannot derive ethical claims from metaphysical claims about the existence of supernatural deities, any more than they can be derived from claims about Darwinian evolution. As pointed out by philosopher Adolf Grunbaum in The Poverty of Theistic Morality, this fallacy was exposed by Socrates in Plato's Euthyphro:

Is the conduct approved by the gods right ("pious"), because of properties of its own, or merely because it pleases the gods to value or command it? In the former case, divine omnibenevolence and revelation are at best ethically superfluous, and in the latter, the absolute divine commands fail to provide any reason at all for imposing particular kinds of conduct.

For if God values and enjoins us to do what is desirable in its own right, then ethical rules do not depend for their validity on divine command, and they can then be independently adopted. But, on the other hand, if conduct is good merely because God decrees it, then nowadays we also have the morally insoluble problem of deciding, in a multi-religious world, which one of the conflicting purported divine revelations of ethical commands we are to accept.